icecube experiment

• Niels Bohr Institute
• Experimental Particle physics

IceCube Experiment

IceCube is a part of the subatomic group at the Niels Bohr Institute. The group includes both experimentalists and theorists (from the Niels Bohr International Academy). Indicated are selected topics of responsibility or research interests within neutrino physics and IceCube.

The IceCube group at the Niels Bohr Institute is engaged with both the experimental and theoretical side of neutrino physics and astrophysics, being embedded within the Discovery Center and involving theorists from the Niels Bohr International Academy.

IceCube members at NBI have a broad science portfolio: from searches for high-energy neutrinos from the most violent astrophysical phenomena in the universe such as gamma-ray bursts, supernovae, active galactic nuclei, etc, to fundamental physics probes of quantum mechanical neutrino oscillations and searches for dark matter.

NBI's participation in IceCube was made possible through the support of the Danish National Research Foundation and members of the IceCube groups are also supported by the Villum Foundation, and the Carlsberg Foundation.

Our Collaboration

Since 2013 NBI has been a full member of the IceCube Collaboration, which includes over 300 scientists from 49 institutions in 12 countries.

The full list of collaborating institutions is available on the collaboration website

IceCube is a polyvalent detector that is well suited for many different areas of research. Our local group at NBI is focusing its efforts in two main areas: low-energy neutrino oscillations, and high-energy astroparticle physics.

Prospective B.Sc. and M.Sc. students are encouraged to contact Jason Koskinen, [email protected], regarding working with the NBI IceCube group and possible Projects.

The IceCube group is engaged in mulitiple outreach projects, and we always welcome groups of interested people to learn more about this fascinating experiment.

Interact with IceCube

Any interested groups are encouraged to contact us regarding activities/events related to IceCube and neutrinos. We can come to you, or you can come to us!

High school classes are always welcome to apply for lectures/activities.

High school students  are invited to individually to join the international  IceCube MasterClass  o n April 15th, 2020: S pend a full day at the Niels Bohr Institute, analyse real data from IceCube to discover astrophysical neutrinos, and discussing physics with researchers from IceCube.

The international IceCube MasterClass at NBI in 2015 was a huge succes, and attracted enthusiastic students from all over the country.

IceCube has exhibits at the reoccuring event of Kulturnatten (Copenhagen Cultural Night) at NBI .

We are happy to tell more, so please contact us.

IceCube in the Media

Below you will find a list of articles, interviews, and other media regarding the IceCube group at NBI.

• Agurketid i fysikken (Weekendavisen, August 2016)
• Iskolde neutrinoer holder på hemmelighederne (videnskab.dk, August 2016)
• Search for 'ghost particle' that could hold secret to dark matter draws a blank (independent.co.uk, August 2016)
• El neutrino que podría explicar por qué existimos... no existe (elmundo.es, August 2016)
• Flotte billeder fra Sydpolen: Ph.d.-studerende på sit livs eventyr (videnskab.dk, March 2016)
• Gennembrud på Sydpolen: Nu kan neutrinoer bruges til astronomi (videnskab.dk, August 2015)
• Neutrinoer forvandler sig på rejse gennem Jorden (videnskab.dk, April 2015)
• "Neutrinoer på Sydpolen", 10 min. præsentation til gymnasieelever (Faculty of Science, University of Copenhagen, November 2014)

Press Releases

• The long hunted sterile neutrino cannot be traced (NBI Press Release, August 2016)
• Detector at the South Pole explores the mysterious neutrinos (NBI Press Release, April 2015)
• IceCube sees first signs of high-energy extraterrestrial neutrinos (NBI Press Release, November 2013)
• Niels Bohr Institute part of the reseach project IceCube at the South Pole (NBI Press Release, October 2013)  

MasterClass

Want to try your first day as a real researcher? See more information about our IceCube MasterClass here.

Publications

Below is a list of publications that have directly involved work from members of the IceCube group at the Niels Bohr Institute.

Work involving our group:

Tom Stuttard and Mikkel Jensen. Neutrino decoherence from quantum gravitational stochastic perturbations . https://arxiv.org/abs/2007.00068

IceCube Collaboration. Constraints on Neutrino Emission from Nearby Galaxies Using the 2MASS Redshift Survey and IceCube. https://arxiv.org/pdf/1911.11809.pdf

IceCube Collaboration. Measurement of Atmospheric Tau Neutrino appearance with IceCube DeepCore . https://arxiv.org/pdf/1901.05366.pdf

IceCube Collaboration. Combined Analysis of Cosmic-Ray Anisotropy with Icecube and HAWC . https://arxiv.org/abs/1708.03005

IceCube Collaboration. Search for Neutrinos from Dark Matter Annihilations in the center of the Milky Way with 3 years of IceCube/DeepCore . https://arxiv.org/abs/1705.08103  

Theoretical papers from our NBIA colleagues:

Mertsch, Philipp, Rameez, Mohamed and Tamborra, Irene. Detection Prospects for high-energy neutrino sources from the anisotropic matter distribution in the local Universe. https://arxiv.org/abs/1612.07311

Ahlers, Markus and Mertsch, Philipp. Origin of Small-Scale Anisotropies in Galactic Cosmic Rays. https://arxiv.org/abs/1612.01873

Bechtol, Keith, Ahlers, Markus, Di Mauro, Mattia, Ajello, Marco and Vandenbroucke, Justin. Evidence against star-forming galaxies as the dominant source of IceCube neutrinos.   https://arxiv.org/abs/1511.00688

Previous publications:

• Publications 2015 >>
• Publications 2016 >>
• Publications 2017 >>
• Publications 2018 >>
• Publications 2019 >>

PhD and Masters theses:

Étienne Bourbeau. Measurement of Tau Neutrino Appearance in 8 Years of IceCube Data (and A Search for astrophysical neutrinos from the Local Universe). PhD thesis, 2021

Ida Storehaug. Improving the Atmospheric Neutrino Flux Estimation in IceCube Master's thesis, 2019

Thomas Halberg. Low Energy Neutrino Reconstruction in IceCube and the IceCube Upgrade Master's thesis, 2019

Mia-Louise Nielsen. Transient Neutrino astrophysics with IceCube-DeepCore . Master's thesis. 2019

Lea Halser. Neutrino Fluence of Gamma-Ray Bursts for Arbitrary Viewing Angles . Master's thesis, 2019

Taus Munck Hansen. Multi-Messenger Probes of the Sources of Ultra-High Energy Cosmic Rays . Master's thesis, 2019

Michael Larson. A Search for Tau Neutrino Appearance with IceCube-DeepCore . PhD thesis, 2018.

Mikkel Jensen. Environmentally induced neutrino decoherence in IceCube Master's thesis, 2018.

Morten Medici. Search for Dark Matter Annihilation in the Galactic Halo using IceCube . PhD thesis, 2017.

Eva Brottmann Hansen. Early Atmospheric Muon Rejection with IceCube-PINGU .  Master's thesis, 2016

Rasmus Westphal Rasmussen. Determination of the neutrino mixing angle theta_23 octantand differentiation amoung flavour symmetrie s . Master's thesis, 2014.

Staff and students

IceCube is a part of the subatomic group at the Niels Bohr Institute and includes both experimentalists and theorists (from the Niels Bohr International Academy). Indicated are selected topics of responsibility or research interests within neutrino physics and IceCube.

Previous members

The IceCube group is based on the Niels Bohr Institute at the University of Copenhagen, Blegdamsvej 17, 2100 København Ø.

New Galactic signal

IceCube sees neutrinos from our own Milky Way galaxy for the first time

Neutrinos from AGN

IceCube neutrinos give us first glimpse into the inner depths of an active galaxy

DFS Poster prize to NBI student

FROM NBI TO ANTARCTICA

Group leader, 

D. Jason Koskinen,  Associate Professor Phone: +45 21 28 90 61 E-mail: koskinen @ nbi.ku . dk

New and surprising duality found in theoretical particle physics

Study reveals new details on what happened in the first microsecond of Big Bang

New physics at stake? Deviation from the standard model of physics confirmed

Show all news

IceCube: Unlocking the Secrets of Cosmic Rays

In the icy wasteland of Antarctica sits a massive particle detector, the IceCube Neutrino Observatory. But searching the surface for the instrument will prove difficult, because the bulk of the observatory is trapped beneath the ice. The international observatory has been hunting for neutrinos — massless, chargeless particles that almost never interact with matter. Now, its observations may solve one of the biggest mysteries in astronomy, answering the questions behind the origin of neutrinos and cosmic rays.

The biggest of them all

The IceCube Neutrino Observatory covers one cubic kilometer near the South Pole. The instrument covers a square kilometer of the surface and extends down to 4,920 feet (1,500 meters) deep. It is the first gigaton neutrino detector ever built.

While photographs of IceCube often show a building sitting on the snowy surface, the real work is done below. The multipurpose experiment includes a surface array, IceTop, an array of 81 stations that sit above the strings. IceTop serves as a calibration detector for IceCube, as well as detecting air showers from primary cosmic rays, and their flux and composition.

The dense inner subdetector, DeepCore, is the powerhouse of the IceCube experiment. Each of the IceTop stations are made up of strings attached to digital optical modules (DOMs) that are deployed on a hexagonal grid spaced 410 feet (125 meters) apart. Each string holds 60 basketball-sized DOMs. Here, deep within the ice, IceCube is able to hunt for neutrinos that come from the sun, from within the Milky Way, and from outside the galaxy. These ghostly particles are connected to cosmic rays, the highest energy particles ever observed.

[ Related: Tracing a Neutrino to Its Source: The Discovery in Pictures ]

Mysterious particles

Cosmic rays were first discovered in 1912. The powerful bursts of radiation collide with Earth constantly, streaming in from all parts of the galaxy. Scientists calculated that the charged particles must form in some of the most violent and least understood objects and events in the universe. The explosive stellar death of a star, a supernova, provides one method of creating cosmic rays; the active black holes at the center of galaxies another.

Because cosmic rays are made up of charged particles, however, they interact with the magnetic fields of stars and other objects they pass by. The fields warp and shift the path of the cosmic rays, making it impossible for scientists to trace them back to their source. 

That's where neutrinos come into play. Like cosmic rays, the low-mass particles are thought to form through violence. But because neutrinos have no charge, they pass by magnetic fields without changing their path, traveling in a straight line from their source.  

"For this reason, the search for the sources of cosmic rays has also become the search for very high energy neutrinos," according to IceCube's website .

However, the same characteristics that make neutrinos such good messengers also mean they are difficult to detect. Every second, approximately 100 billion neutrinos pass through one square inch of your body. Most of them come from the sun, and are not energetic enough to be identified by IceCube, but some are likely to have been produced outside of the Milky Way.

Spotting neutrinos requires the use of very clear material such as water or ice. When a single neutrino crashes into a proton or neutron inside an atom, the resulting nuclear reaction produces secondary particles that give off a blue light known as Cherenkov radiation.

"The neutrinos that we detect are like fingerprints that help us understand the objects and phenomena where the neutrinos are produced," according to the IceCube team .

Harsh conditions

The South Pole may not be outer space, but it brings its own challenges. Engineers began construction on IceCube in 2004, a seven-year project that was completed on schedule in 2010. Construction could only take place for a few months each year, over the Southern Hemisphere's summer, which occurs from November to February. 

Boring 86 holes required a special type of drill — two of them, actually. The first advanced through the firn, a layer of compacted snow, down to about 164 feet (50 meters). Then a high-pressure hot water drill melted through the ice at speeds of about 2 meters (6.5 feet) per minute, down to the depth of 2,450 meters (8,038 feet, or 1.5 miles).

"Together, the two drills were able to consistently produce almost perfect vertical holes ready for deployment of instrumentation at a rate of one hole every two days," according to IceCube .

The strings then had to be quickly deployed into the melted water before the ice refroze. Freezing took a few weeks to stabilize, after which the instruments remained untouchable, permanently frozen in the ice and unable to be repaired. The failure rate of the instruments has been extremely slow, with fewer than 100 of the 5,500 sensors currently nonoperational.

IceCube began making observations from the start, even while other strings were being deployed.

When the project first began, researchers were unclear about how far light would travel through the ice, according to Halzen. With that information well established, the collaboration is working towards IceCube-Gen2. The upgraded observatory would add approximately 80 more detector strings, while the understanding of the properties of ice will allow researchers to place the sensors more widely apart than their original conservative estimates. IceCube-Gen2 should double the size of the observatory for roughly the same cost.

Incredible science

IceCube began hunting for neutrinos before it was completed, producing several intriguing scientific results along the way. 

Between May 2010 and May 2012, IceCube observed 28 very high-energy particles. Halzen attributed the detector's ability to observe these extreme events to the completion of the detector.

"This is the first indication of very high-energy neutrinos coming from outside our solar system, with energies more than one million times those observed in 1987 in connection with a supernova seen in the Large Magellanic Cloud," says Halzen said in a statement . "It is gratifying to finally see what we have been looking for. This is the dawn of a new age of astronomy."

In April 2012, a pair of high energy neutrinos were detected and nicknamed Bert and Ernie, after the characters from the children's television show "Sesame Street." With energies above 1 petaelectronvolt (PeV), the pair were the first definitively detected neutrinos from outside the solar system since the 1987 supernova.

"It is a major breakthrough," said Uli Katz, a particle physicist at University of Erlangen-Nuremberg, in Germany, who was not involved with the research. "I think it is one of the absolute major discoveries in astro-particle physics," Katz told Space.com .

These observations resulted in IceCube being awarded the Physics World 2013 Breakthrough of the Year .

Another major payoff came on December 4, 2012, when the observatory detected an event that the scientists called Big Bird, also from "Sesame Street." Big Bird was a neutrino with an energy exceeding 2 quadrillion electron volts, more than a million million times greater than the energy of a dental X-ray, packed into a single particle with less than a millionth of a mass of an electron. At the time, it was the highest-energy neutrino ever detected; as of 2018, it still ranks second.

With the help of NASA's Fermi Gamma-ray Space telescope, scientists tied Big Bird to the highly energetic outburst of a blazar known as PKS B1424-418. Blazars are powered by supermassive black holes at the center of a galaxy. As the black hole gobbles down material, some of the material is deflected into jets carrying so much energy they outshine the stars in the galaxy. The jets accelerate matter, creating neutrinos and the fragments of atoms that create some cosmic rays.

Starting in the summer of 2012, the blazar shone between 15 and 30 times brighter in gamma rays than its average before the eruption. A long-term observation program named TANAMI, which routinely monitored nearly 100 active galaxies in the southern sky, revealed that the core of the galaxy's jet had brightened four times between 2011 and 2013.

"No other of our galaxies observed by TANAMI over the life of the program has exhibited such a dramatic change," Eduardo Ros, from the Max Planck Institute for Radio Astronomy (MPIfR) in Germany, said in a 2016 statement . The team calculated that the two events were linked.

"Taking into account all of the observations, the blazar seems to have had means, motive and opportunity to fire off the Big Bird neutrino, which makes it our prime suspect," said Matthias Kadler, a professor of astrophysics at the University of Würzburg in Germany."

In July 2018, IceCube announced that, for the first time, it had tracked neutrinos back to their source blazar. In September 2017, thanks to a newly installed alert system that broadcast to scientists around the world within minutes of detecting a strong neutrino candidate, researchers were able to quickly turn their telescopes in the direction that the new signal originated. Fermi alerted researchers to the presence of an active blazar, known as TXS-0506+056, in the same part of the sky. New observations confirmed that the blazar was flaring, emitting brighter-than-usual bursts of energy.

For the most part, TXS is a typical blazar; it's one of the 100 brightest blazars detected by Fermi. However, while the 99 others are also bright, they haven't hurled neutrinos toward IceCube. In recent months, TXS has been flaring, brightening and dimming as much as a hundred times stronger than in previous years.

"Tracking that high-energy neutrino detected by IceCube back to TXS 0506+056 makes this the first time we've been able to identify a specific object as the probable source of such a high-energy neutrino," Gregory Sivakoff, of the University of Alberta in Canada, said in a statement .

IceCube isn't finished yet. The new alert system will keep astronomers on their toes in future years. The observatory has a planned lifetime of 20 years, so there's at least another decade of incredible discoveries coming from the South Pole observatory.

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: [email protected].

Get the Space.com Newsletter

Breaking space news, the latest updates on rocket launches, skywatching events and more!

Nola Taylor Tillman is a contributing writer for Space.com. She loves all things space and astronomy-related, and enjoys the opportunity to learn more. She has a Bachelor’s degree in English and Astrophysics from Agnes Scott college and served as an intern at Sky & Telescope magazine. In her free time, she homeschools her four children. Follow her on Twitter at @NolaTRedd

Space pictures! See our space image of the day

'The last 12 months have broken records like never before': Earth exceeds 1.5 C warming every month for entire year

Stick to the shade in new extended 'Dune: Awakening' gameplay trailer (video)

Most Popular

• 2 'Unbreakable' quantum communication closer to reality thanks to new, exceptionally bright photons
• 3 Star-packed Triangulum Galaxy shines in new Hubble Telescope image
• 4 Lego Star Wars Mos Espa Podrace Diorama review
• 5 Heaviest antimatter particle ever discovered could hold secrets to our universe's origins

CERN Accelerating science

Cosmic neutrinos and more: IceCube’s first three years

The IceCube Neutrino Observatory at the South Pole has been collecting data on some of the most violent collisions in the universe

18 December, 2014

By Christine Sutton

One of the first two events from IceCube produced by a neutrino with an energy of about 1 PeV – and a first hint of the detection of astrophysical neutrinos (Image: IceCube Collaboration)

For the past four years, the IceCube Neutrino Observatory, located at the South Pole, has been collecting data on some of the most violent collisions in the universe. Fulfilling aspirations, the detector has observed neutrinos from beyond the Solar System with energies above 60 TeV, at the “magic” 5 σ significance. These neutrinos are just one highlight of IceCube’s broad physics programme, which encompasses searches for astrophysical neutrinos, searches for neutrinos from dark matter, studies of neutrino oscillations, cosmic-ray physics, and searches for supernovae. All of these studies take advantage of a unique detector at a unique location: the South Pole.

Read more: " Cosmic neutrinos and more " – CERN Courier

Also On At CERN

Cern70 community event: your questions answer..., refuse, reduce, reuse, recycle, repeat, cern welcomes estonia as its 24th member stat..., join cern’s 70th birthday celebrations on 17 ..., how can i use cern ideasquare, cern science gateway featured in time magazin..., bike to work 2024: cern achieves the best par..., cern and pro helvetia announce the artists se..., coming together to celebrate cern70.

Extreme 'ghostly' particles detected in our galaxy for the first time

High-energy neutrinos, formed from violent astronomical events, were previously only found in galaxies with very active black holes.

One afternoon in January 2022, three scientists huddled over the results of their most recent analysis, which had used machine learning to sort through a decade of data from the enormous IceCube Neutrino Observatory , built underground in the remote, icy desert of the South Pole .

Neutrinos, mysterious subatomic particles that originate from violent astronomical events, such as star explosions and active black holes, are incredibly difficult to detect. Their tiny masses and ability to pass through gas clouds and even solid planets allow them to zip around space nearly unnoticed.

But on that day, for the first time, the researchers saw an excess of neutrinos in the data from our own galaxy, corresponding to the Milky Way ’s central band of stars that arcs across the sky.   (See photos of the IceCube observatory.)

“We've been looking at the Milky Way for millennia, and us three are the first ones to see it in something other than light,” Naoko Kurahashi Neilson , a physicist at Drexel University, told the other two researchers, graduate students Stephan Sclafani and Mirco Hünnefeld, that day. “Don't let the romance of this moment slip away.”

Because neutrinos carry valuable information about the universe, the discovery means that our galaxy may be an important piece in understanding how the cosmos’ most energetic happenings unfold, according to a new study from the IceCube team, published June 29 in Science .  

Since it went live in 2011, the observatory has only detected neutrinos from outside the Milky Way, mostly in galaxies containing extremely active black holes .

Where particles meet astronomy

  For most of human history, observers had one tool to study the cosmos: their own eyes. And what they saw was our sun, the moon, the brightest planets, and the stars in the Milky Way tracing a thick band across the sky.

The invention of telescopes eventually revealed different forms of light, those more energetic than our eyes can decipher, such as exploding stars and the bright environs surrounding active black holes.

But cosmic entities don’t expel only light.

“For generations, astronomers have been trying to map out the full scope of the heavens, and, in optical astronomy that's been tremendously successful,” says John F. Beacom , a neutrino physicist at the Ohio State University who is not associated with the new paper. “In neutrino astronomy, it's just getting started.”

The IceCube neutrino detector, which sits 0.9 mile below the surface, hosts 5,160 basketball-size modules encased in a cubic kilometer of Antarctic ice. Each of those modules look for light signals created when particles interact with the ice. (Read how neutrinos may travel faster than the speed of light.)

Neutrinos pass through most matter unscathed, although occasionally, one will interact with matter, initiating a series of events that physicists can see with their sensitive detectors. Of the handful that exist, IceCube is the largest.

You May Also Like

Behold: The first picture of the black hole at the center of our galaxy

What is causing these massive, mysterious explosions in space?

What’s out there? Why humanity keeps pushing the cosmic frontier.

But there’s also a lot of particles zooming through that scientists don’t want. “Searching for neutrinos is always very difficult, because we have to fight many backgrounds,” says Elisa Resconi , an IceCube team member at Germany’s Technical University of Munich.

One way to help weed out unwanted particles is by using Earth itself as a shield. Although IceCube is based in Antarctica, most of its detections focus on the northern sky. But the Milky Way’s center and its most active locations are visible only from the southern sky. That means the researchers had to use creative methods to dig through the background and pull out the signals corresponding to neutrinos.

So Kurahashi Neilson, Sclafani, and Hünnefeld trained a program to scour through IceCube data collected between May 2011 and May 2021 and select a specific type of signal, ones that look like a blob or burst in the detector. These are called “cascade” events, and they occur from a neutrino slamming into an ice particle within the detector and releasing the energy quickly. This type of signature, though, doesn’t trace easily to a source location on the sky. Instead, it’s akin to the blurry vision you might have if you neglect to put your glasses on, says Kurahashi Neilson.

Don't let the romance of this moment slip away. Naoko Kurahashi Neilson , Drexel University physicist

When they looked at the results, in January 2022, the researchers saw an obvious glow dispersed along the galaxy’s plane and toward its center.

Deciphering a long-standing question

  What is causing this galactic neutrino glow may tie to a 110-year-old mystery surrounding particles known as cosmic rays , says IceCube Principal Investigator Francis Halzen , of the University of Wisconsin-Madison.   (Read: Origins of mystery space radiation finally found.)

These are high-energy protons and other particles that meander through the universe, including our galaxy’s disk, following the paths drawn by magnetic fields. Physicists have known since 1912 that cosmic rays exist and bombard Earth, but they still don’t know what energizes these particles to such extremes.

They do know, however, that when cosmic rays interact with matter, they generate high-energy neutrinos. (Similar to how light comes in different energies, so do neutrinos. The sun, for example, releases much lower-energy neutrinos; those detected in 2013 were high energy.)

So, it’s possible these newly detected neutrinos may be the result of cosmic rays colliding with the celestial stuff of our own galaxy. IceCube could also be seeing signals from individual energetic objects, like supernova explosions, that boost protons to extreme energies that then slam into that galactic gas. It will take at least another few years to reveal what this glow is, say researchers.

Expanding the hunt for neutrinos

Another large-scale neutrino detector, soon to become operational in the Mediterranean Sea, should help. The KM3Net , a kilometer-size instrument, follows a similar principle as IceCube.

When a neutrino collides with a water molecule, for instance, lines of detectors will see flashes of light. Because KM3Net is situated in the Northern Hemisphere, it can use Earth to block out much of the background as it looks toward the galactic plane . This should disentangle even more mysteries surrounding neutrinos and their role in cataclysmic events.

Related Topics

• SPACE EXPLORATION
• BLACK HOLES

Colossal gravitational waves—trillions of miles long—found for the first time

The world’s most powerful telescope is rewriting the story of space and time

This supermassive black hole was formed when the universe was a toddler

The brightest blast ever seen in space continues to surprise scientists

NASA just found a question mark in space. What exactly is it?

• Environment
• Paid Content

History & Culture

• History & Culture
• Mind, Body, Wonder
• Terms of Use
• Privacy Policy
• Your US State Privacy Rights
• Children's Online Privacy Policy
• Interest-Based Ads
• About Nielsen Measurement
• Do Not Sell or Share My Personal Information
• Nat Geo Home
• Attend a Live Event
• Book a Trip
• Inspire Your Kids
• Shop Nat Geo
• Visit the D.C. Museum
• Learn About Our Impact
• Support Our Mission
• Advertise With Us
• Customer Service
• Renew Subscription
• Manage Your Subscription
• Work at Nat Geo
• Sign Up for Our Newsletters
• Contribute to Protect the Planet

Copyright © 1996-2015 National Geographic Society Copyright © 2015-2024 National Geographic Partners, LLC. All rights reserved

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

• View all journals
• Explore content
• About the journal
• Publish with us
• Sign up for alerts
• Research Highlight
• Published: 14 April 2021

IN RETROSPECT

Ten years of IceCube

• Ankita Anirban 1  

Nature Reviews Physics volume  3 ,  page 307 ( 2021 ) Cite this article

231 Accesses

1 Citations

12 Altmetric

Metrics details

• High-energy astrophysics
• Particle astrophysics

Sunk deep into the ice of the South Pole lies a huge neutrino detector, IceCube. Completed in 2011, IceCube searches for neutrinos coming from astrophysical sources. Because neutrinos hardly interact with the inter-stellar medium, neutrino astronomy can provide new insights into astrophysical phenomena that are not available from electromagnetic observations. IceCube is part of the world-wide network of multi messenger astronomy instruments. IceCube data is also of interest to high-energy particle physicists because neutrinos generated by astrophysical sources have significantly higher energies than those achievable in particle accelerators on Earth.

Despite the huge challenges of working in such a remote location, Antarctica was chosen as the site for IceCube as it offered a huge volume of pure, uniform ice. In addition, other neutrino detectors were all in the northern hemisphere, so Antarctica provided a view of the southern sky. Over the course of seven years, 86 holes were drilled into the ice, reaching the bedrock at a depth of up to 2500 m. Into each hole, a vertical string lined with 60 photodetectors was lowered into the ice. In total, the experiment contains 5160 extremely sensitive photodetectors, capable of detecting energies up to the order of exaelectronvolts (10 18  eV).

This is a preview of subscription content, access via your institution

Access options

Access Nature and 54 other Nature Portfolio journals

Get Nature+, our best-value online-access subscription

24,99 € / 30 days

cancel any time

Subscribe to this journal

Receive 12 digital issues and online access to articles

92,52 € per year

only 7,71 € per issue

Buy this article

• Purchase on SpringerLink
• Instant access to full article PDF

Prices may be subject to local taxes which are calculated during checkout

Related articles

IceCube Collaboration, Aartsen, M. G. et al. Evidence for High-Energy Extraterrestrial Neutrinos at the IceCube Detector. Science 342 , 1242856 (2013)

Article   Google Scholar  

The IceCube, Fermi-LAT, MAGIC, AGILE, ASAS-SN, HAWC, H.E.S.S, INTEGRAL, Kanata, Kiso, Kapteyn, Liverpool telescope, Subaru, Swift/NuSTAR, VERITAS, and VLA/17B-403 teams. Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A. Science 361 , eaat1378 (2018)

Article   ADS   Google Scholar  

The IceCube Collaboration., Aartsen, M. G. & Abbasi, R. et al. Detection of a particle shower at the Glashow resonance with IceCube. Nature 591 , 220–224 (2021)

Download references

Author information

Authors and affiliations.

Nature Reviews Physics https://www.nature.com/natrevphys/

Ankita Anirban

You can also search for this author in PubMed   Google Scholar

Corresponding author

Correspondence to Ankita Anirban .

Rights and permissions

Reprints and permissions

About this article

Cite this article.

Anirban, A. Ten years of IceCube. Nat Rev Phys 3 , 307 (2021). https://doi.org/10.1038/s42254-021-00315-4

Download citation

Published : 14 April 2021

Issue Date : May 2021

DOI : https://doi.org/10.1038/s42254-021-00315-4

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

This article is cited by

Searches for magnetic monopoles.

• Iulia Georgescu

Nature Reviews Physics (2022)

Quick links

• Explore articles by subject
• Guide to authors
• Editorial policies

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

• Accelerators
• Photon Science
• Particle Physics

Deutsches Elektronen-Synchrotron DESY A Research Centre of the Helmholtz Association

Neutrino Astronomy

Gamma astronomy, research technology.

• Website of the German partners for IceCube-Gen2 The planned expansion of the IceCube observatory at the South Pole marks a new era in neutrino astronomy.
• Website of the Multimessenger School The International Helmholtz-Weizmann Research School on Multimessenger Astronomy provides a world-class international training and education environment.
• Emmy Noether Programme
• Helmholtz Funding Programs For Leading Female Scientists
• Humboldt Research Fellowship
• Young Investigators Groups
• Investitionsbank des Landes Brandenburg (ILB)

IceCube: The world’s largest neutrino telescope

IceCube is a state-of-the-art neutrino telescope at the geographical South Pole, buried deep under the surface of the Antarctic ice cap. With more than five thousand optical sensors distributed over a cubic kilometer of ice, IceCube is the biggest particle detector world-wide.

At first glance, the South Pole may appear to be a strange site for deploying such an instrument. But there are crucial advantages that outweigh the remoteness of the site. The polar ice is about 3 km deep, incredibly transparent, and the level of background light is extremely low. That makes it an ideal medium to detect the faint light signals produced in the interactions of high-energy neutrinos. The necessary on-site infrastructure is provided by the Amundsen-Scott polar station, run by the National Science Foundation of the United States.

IceCube is primarily designed to observe neutrinos from the most violent astrophysical sources in our universe. Neutrinos, almost massless particles with no electric charge, can travel from their sources to Earth with essentially no attenuation and no deflection by magnetic fields.

IceCube was constructed over 7 years from 2004 to 2011, and is fully operational since then. All cargo was transported by plane from McMurdo station located at the Antarctic coast to South Pole station. 2.5 km deep holes have been drilled in the ice using hot water at high pressure to deploy the sensors that detect the faint light from the neutrino interactions.

The in-ice component of the completed IceCube consists of 5,160 optical sensors called digital optical modules (DOMs), each one equipped with a 25cm diameter photomultiplier tube and associated electronics. The DOMs are attached to vertical cables (“strings”), frozen into the 86 boreholes, and arrayed over a cubic kilometer at depths between 1.450 meters to 2.450 meters.

Eight of these strings at the center of the array were deployed in a more compact configuration than the rest of the array. This denser configuration forms the DeepCore subdetector, which has a lower neutrino energy threshold than the main in-ice array of about 10 GeV, creating the opportunity to study neutrino oscillations.

The optical sensors of IceCube even respond to a single arriving photon. Inside the optical modules, the photon signals are amplified, converted into electrical pulses and then translated into digital signals. Therefore, each module has its own mini-computer as well as a precision clock to measure the arrival time of the photons to an accuracy of 2 nanoseconds (2*10-9sec). The digital information is then sent over kilometer-long cables to the central data acquisition system in the IceCube Lab, processed there, and shipped to the University of Wisconsin in Madison, USA, via a daily satellite link.

Neutrinos are not observed directly, but when they interact with the ice they produce electrically charged secondary particles that in turn emit Cherenkov light . The light pattern and arrival time recorded in IceCube’s sensors is used to determine the direction and energy of the incoming neutrino. This lead in 2013 to the discovery of the long sought-after cosmic neutrinos and the opening of a new field in science, the multi-messenger astronomy, where the information from photons, neutrinos and now also gravitational waves is combined to study the high-energy universe. The astrophysical sources of the neutrinos observed by IceCube are still largely unknown. However, since an observation in 2017 there is strong evidence that at least some of them are produced in the jets formed around the central black holes of active galaxies. More about this observation can be found here: https://multimessenger.desy.de/ .

IceCube is operated by the international IceCube Collaboration, over 300 researchers from more than 50 institutions worldwide. The collaboration is also responsible for the rich scientific research program, which besides multi-messenger astronomy also includes many unique measurements in particle physics and searches for beyond-the-standard model particles and phenomena.

DESY hosts the second largest group in the IceCube collaboration. The group’s most important contributions to the IceCube project are:

• Production and test of 1250 of the more than 5000 optical modules
• Development and manufacturing of electronic components for the data acquisition system
• Software development for the data analysis
• Development and test of new methods of particle detection
• European TIER1 center for data archiving and analysis
• Data Analysis

Contact | Imprint | Data Privacy Policy | Declaration of Accessibility © 2024 Deutsches Elektronen-Synchrotron DESY

• IceCube-Gen2
• Science Scope
• Parameterization and Figures
• Publications
• Contributions
• Latest News
• For the Media

IceCube-Gen2 releases Technical Design Report, part III

A facility where the frontiers of neutrino astrophysics and particle physics meet

IceCube-Gen2, the planned IceCube Neutrino Observatory extension, builds on the exceptional properties of the Antarctic ice sheet and the expertise of the international team that constructed and operates the first gigaton neutrino detector to explore uncharted regions of the extreme universe and test the limits of particle physics.

the IceCube-Gen2 facility at a glance

WORLD’S LARGEST NEUTRINO DETECTOR

OPTICAL AND RADIO SENSORS

INSTRUMENTED ANTARCTIC ICE

NEUTRINOS DETECTED EVERY YEAR

ENERGY RANGE FROM SUPERNOVAE TO COSMOGENIC NEUTRINOS

DETECTOR ARRAYS, INCLUDING 4 IN-ICE, 2 SURFACE AND 1 RADIO ARRAY

SCIENTISTS FROM 60 INSTITUTIONS

COUNTRIES IN NORTH AMERICA, EUROPE, ASIA & AUSTRALIA

THE NEXT-GENERATION ICECUBE NEUTRINO OBSERVATORY

From high-energy precision neutrino physics to ultra-high-energy neutrino and cosmic-ray astrophysics.

IceCube-Gen2 encompasses three detector arrays: the huge optical array will increase the detection capabilities for astrophysical high-energy neutrinos; the surface array will enable improved cosmic-ray science as well as gamma-ray measurements; and the radio array will detect neutrinos up to the EeV scale.

INTERNATIONAL AND MULTIDISCIPLINARY SCIENCE AT THE SOUTH POLE

Neutrino and multimessenger Astrophysics

The improved capabilities of IceCube-Gen2 will allow us to resolve the high-energy neutrino sky from TeV to EeV energies and will reveal the sources and propagation of the highest energy particles in the universe.

neutrino Physics

With more than one million neutrinos detected every year, IceCube-Gen2 will be a flagship neutrino physics experiment. Surveying the high-energy frontier will be crucial to exploring beyond-the-standard model features in neutrino physics and may become a discovery machine for heavy dark matter particles.

Earth Sciences

The optical and radio properties of the Antarctic ice in and around the IceCube-Gen2 instrumented volume will be thoroughly studied to calibrate the different detector arrays. This will become a unique opportunity to deepen our understanding Earth’s climate history.

MEET OUR COLLABORATORS

The international IceCube-Gen2 Collaboration brings together more than 400 scientists from 15 countries. It was born from and expands on the experience and expertise of the team that built IceCube, the first cubic-kilometer-scale neutrino detector.

The IceCube Experiment

The IceCube neutrino observatory is a 1 gigaton Cherenkov detector using Antarctic ice as a detection medium for high energy atmospheric and astrophysical neutrinos. The experiment is located at the South Pole, right in the middle of the map above. (Just for fun, this map shows the winds -- it is pretty tough down for the IceCube collaborators that go down there!) The official webpage for IceCube is here, and includes the latest weekly report from the pole!

Proposed as a telescope for neutrino astronomy, deployment of IceCube optical modules into the ice began in 2005. The last of the 5160 digital optical modules (DOMs) which make up the 86-string IceCube detector, were deployed in late 2010. The above event display is of a neutrino event that occurred in the ice, sending a muon upward through the detector. IceCube is now running in this configuration and has discovered exciting astrophysical neutrino events.

We do many other Beyond Standard Model Searches. For example, we have also performed a very precise search for Lorentz Violation. Our work on this is described in our blog for the Journal Nature. Our Nature Physics paper is available on arXiv: arXiv:1709.03434.

• "Imaging Galactic Dark Matter with High-Energy Cosmic Neutrinos," arXiv:1703.00451. Phys.Rev.Lett. 119, no. 20,201801, 2017.
• "Search for Non-Standard Neutrino Interactions with IceCube-DeepCore," arXiv:1709.07079. Phys.Rev.D 97, no. 7, 072009, 2018.
• "Solar Atmospheric Neutrinos and the Sensitivity Floor for Solar Dark Matter Annihilation Searches," arXiv:1703.0779.8 JCAP 1707, no. 07, 024, 2017.
• "High-energy neutrino attenuation in the Earth and its associated uncertainties," arXiv:1706.09895. JCAP 1711, no. 11, 012, 2017.
• "The Desktop Muon Detector: A simple, physics-motivated machine- and electronics-shop project for university students," arXiv:1606.01196. American Journal of Physics, 85, 948, 2017.
• "The CosmicWatch Desktop Muon Detector: a self-contained, pocket sized particle detector," arXiv:1801.03029. JINST 13, no. 03, P03019, 2018.

This page was updated July 2018

Accessibility Tools

Highlight links, change contrast, increase text size, increase letter spacing, readability bar, dyslexia friendly font, increase cursor size, icecube neutrino observatory.

The IceCube Neutrino Observatory is the detector of its kind, designed to observe the cosmos from deep within the South Pole ice. IceCube uses a cubic kilometer — a billion tons — of the ice cap beneath the South Pole to detect neutrinos.

Neutrinos with energies beyond 1 PeV are produced in violent astrophysical sources such as active galactic nuclei, powered by matter accreting onto supermassive black hole. Lower energy neutrinos from the GeV to the TeV scale are produced by cosmic rays colliding with Earth’s atmosphere, allowing us to probe neutrino physics in ways complementary to long-baseline experiments like T2K, NOvA, and DUNE.

The MSU IceCube group is one of the largest in the IceCube Collaboration, with 5 faculty members, 2 engineers, 1 software engineer, 5 postdoctoral researchers, 12 graduate students, and 6 undergraduate researchers (as of summer 2021). We work in many areas of IceCube science, including searches for astronomical neutrino sources, measurements of the high energy astrophysical neutrino flux, and measurements of neutrino properties using atmospheric neutrinos. A particular focus is the application of machine learning methods to analysis of IceCube data, and several faculty and students are members of the CMSE department as well as Physics and Astronomy. We are also heavily involved in construction of the IceCube Upgrade, to be deployed at the South Pole in the austral summer of 2023/24, and of the planned IceCube-Gen2 Observatory. Approximately 300 physicists from 53 institutions in 12 countries make up the IceCube Collaboration. The National Science Foundation (NSF) provided the primary funding for the IceCube Neutrino Observatory, with assistance from partner funding agencies around the world.

April 9, 2014

Exotic Space Particles Slam into Buried South Pole Detector

The IceCube experiment has taken hits from three neutrinos carrying energies above the outlandishly high peta–electron volt range that suggest they may radiate from titanic explosions in the depths of space  

By Clara Moskowitz

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing . By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

SAVANNAH, Ga.—A belowground experiment at the South Pole has now discovered three of the highest-energy neutrinos ever found, particles that may be created in the most violent explosions of the universe. These neutrinos all have energies at the absurdly high scale of peta–electron volts—roughly the energy equivalent of one million times a proton’s mass. (As Albert Einstein showed in his famous E = mc 2 equation, energy and mass are equivalent, and such a large amount of mass converts to an extreme level of energy.) The experiment, called IceCube, reported the discovery of the first two —nicknamed Ernie and Bert —last year, and announced the third Monday here at the American Physical Society meeting. “Internally, it’s known as Big Bird,” said IceCube physicist Chris Weaver of the University of Wisconsin–Madison.   These neutrinos are valuable because they are extremely standoffish, rarely ever interacting with other particles, and are uncharged, so their direction is never swayed by magnetic fields in the universe. Thus, their trajectories should point straight back to their source, which astronomers think could be a variety of intense events such as humongous black holes accreting matter, explosions called gamma-ray bursts or galaxies forming stars at furious rates.   This penchant for noninteraction also makes neutrinos extremely difficult to detect. The IceCube experiment looks for the very rare occasions when neutrinos collide with atoms in a cubic kilometer of ice buried underneath the South Pole. Such shielding is necessary to filter out collisions from other particles, but does not inhibit neutrinos. The experiment capitalizes on the naturally pure ice there, using a region that extends twice the depth of the Grand Canyon underground. Thousands of light detectors are imbedded in the ice to catch the little blips of light created when neutrinos are caught. Such interactions are so infrequent that IceCube researchers had to search for two years to find these three high-energy neutrinos. During that time span the instrument also detected 34 neutrinos of somewhat lower energies. Some of these neutrinos are thought to be contamination created when charged particles called cosmic rays hit Earth’s atmosphere, but some portion of IceCube’s haul likely came directly from violent processes in the cosmos. Those particles are called astrophysical neutrinos. “It looks like we have reached compelling evidence for astrophysical neutrinos,” said U.W.–Madison physicist Albrecht Karle, a member of the IceCube team.   Cosmic rays themselves are a mystery. The most energetic among them are thought to originate in the same processes that spawn astrophysical neutrinos. Yet because cosmic rays (which, despite the name, are actually high-energy particles) are charged, they travel curved paths, shaped by magnetic fields, through the universe. As a result, they do not preserve information about where they came from. Studying neutrinos is a way to try to understand the origin of high-energy cosmic rays, which are somehow sped up to nearly light-speed in some sort of cosmic particle accelerator. Just how this happens is an open question that shows just how much we do not know about the most violent processes in the universe. “This is the biggest mystery of our century,” says Toshihiro Fujii, a cosmic-ray researcher at the University of Chicago’s Kavli Institute for Cosmological Physics. Fujii was not involved in IceCube, but says its findings will aid his goal of understanding cosmic rays.   One debate about high-energy neutrinos and cosmic rays is whether they come from galactic or extragalactic sources—in other words, do they originate inside or outside our Milky Way Galaxy? Most theories favor extragalactic sources such as active galactic nuclei—supermassive black holes at the centers of other galaxies that are gorging on matter. Another option: gamma-ray bursts, the brightest explosions known in the universe, which may occur during some supernovae or when two neutron stars merge. Or maybe these particles are a by-product of galaxies that are colliding, sending shock waves through their gas that causes stars to form at furious speeds. It is even possible that dark matter, the invisible stuff that far outweighs the normal matter in the universe, is somehow creating cosmic rays and high-energy neutrinos.   Based on the direction the 37 neutrinos were traveling when they hit IceCube, few of them appear to have originated in the galactic plane, the densest part of the Milky Way. This suggests they come from outside our galaxy. “Some of the most interesting events are far from the galactic plane,” said IceCube researcher Nathan Whitehorn at U.W.–Madison. “Purely galactic explanations are hard.”   As the experiment collects more high-energy neutrinos over the coming years, IceCube’s map of neutrino sources on the sky will improve. Scientists are particularly interested in whether any of the particles IceCube sees can be traced back to known cosmological objects, such as visible active galactic nuclei or gamma-ray bursts. “To this day we don’t have any evidence of correlation with a known source,” says Naoko Kurahashi Neilson, another IceCube collaborator at U.W.–Madison, “but that is high on the list.”  

The ICECUBE Neutrino Experiment

About icecube.

The IceCube Neutrino Observatory is the first detector of its kind, designed to observe the cosmos from deep within the South Pole ice. An international group of scientists responsible for the scientific research makes up the IceCube Collaboration.

Encompassing a cubic kilometer of ice, IceCube searches for nearly massless subatomic particles called neutrinos. These high-energy astronomical messengers provide information to probe the most violent astrophysical sources: events like exploding stars, gamma-ray bursts, and cataclysmic phenomena involving black holes and neutron stars.

The Antarctic neutrino observatory, which also includes the surface array IceTop and the dense infill array DeepCore, was designed as a multipurpose experiment. IceCube collaborators address several big questions in physics, like the nature of dark matter and the properties of the neutrino itself. IceCube also observes cosmic rays that interact with the Earth’s atmosphere, which have revealed fascinating structures that are not presently understood.

Approximately 300 physicists from 48 institutions in 12 countries make up the IceCube Collaboration. The international team is responsible for the scientific program, and many of the collaborators contributed to the design and construction of the detector. Exciting new research conducted by the collaboration is opening a new window for exploring our universe.

The National Science Foundation (NSF) provided the primary funding for the IceCube Neutrino Observatory, with assistance from partner funding agencies around the world. The University of Wisconsin–Madison is the lead institution, responsible for the maintenance and operations of the detector. Funding Agencies in each collaborating country support their scientific research efforts.

• Back to top

My Information

The world’s largest neutrino detector

From icecube to icecube-gen2.

With groundbreaking discoveries, IceCube has established neutrino astronomy as a new discipline for the exploration of the universe. By observing neutrinos, we can obtain knowledge about regions of the cosmos where light is unable to provide useful information. In order to fully exploit the potential of this new window to the universe, the international IceCube Collaboration is planning a significant expansion of the IceCube detector at the South Pole.

A gigantic detector deep in the ice

The detection of neutrinos requires sophisticated technology. Although neutrinos are among the most common elementary particles in the universe, they are extremely difficult to catch. Neutrinos pass through any matter almost undisturbed. To detect them despite this very little interaction, huge detectors are needed. The current IceCube detector takes advantage of its unique geographical location at the South Pole: It uses one cubic kilometer of glacial ice as a natural medium. Once a neutrino collides with an ice molecule, it creates charged particles that emit blue to ultraviolet light on their way through the ice, known as Cherenkov light. Several thousands of light sensors thousands of meters deep in the ice capture these faint light signals. The optical sensors are placed in glass spheres attached to long cables like pearls on a string and frozen in the polar ice.

IceCube-Gen2 will enlarge the detector’s volume to a gigantic eight cubic kilometers. This will increase the detection rate of cosmic neutrinos by a factor of ten. The detector will be integrated into IceCube’s existing infrastructure, and three new components will be added to it: First, the optical detector will be upgraded and expanded by adding 120 additional cables equipped with thousands of new, more sophisticated light sensors. Second, radio detectors will be set up near the surface of the ice over an area of ​​500 square kilometers. They will improve the sensitivity of the detector at the highest energies by two orders of magnitude. Third, an extended array on the ice surface will detect atmospheric particle showers that are triggered by cosmic rays.

10 times more discoveries

“So far we have only seen the tip of the iceberg – only a very small part of the neutrino sky has been resolved. With IceCube Gen2 we strive to increase the discovery rate by a factor of ten!”

Professor Marek Kowalski, DESY & HU Berlin

Visualization of the Ice-Cube expansion to IceCube-Gen2 (Credit: DESY, Science Communication Lab)

Perfect for neutrino astronomy

IceCube-Gen2 will measure the properties of neutrino sources with unprecedented accuracy. Not only will the telescope’s detection rate increase, but also the range of energies it will be able to detect – up to the highest neutrino energies. For this purpose, additional instrumentation will also record radio signals from neutrino interactions. The light yield of the optical sensors will be optimized using new technology to measure Cherenkov radiation. Artificial intelligence (AI) methods are used to transmit and evaluate the data from theses light patterns. This also enables faster reaction times to neutrino events in order to quickly point other astronomical telescopes to their sources. A surface array of particle detectors on the ice helps to distinguish neutrinos that come from outer space from neutrinos that are generated by particle collisions in the Earth’s atmosphere.

Winterover at the South Pole (Credit: Martin Wolf, TU München / IceCube, NSF).

New technology from Germany and Europe

Research groups in Germany and across Europe are already making a significant contribution to the first phase of Gen2, IceCube’s upgrade. The upgrade will be completed by 2024. The full expansion to IceCube-Gen2 will be finished by 2032. Due to the special requirements of the South Pole and the deep glacial ice, most technologies have to be developed from the ground up – for instance, smart readout systems for data transmission that use extremely energy-saving electronics while achieving maximum efficiency.

High-performance optical sensors

New sensors that are being developed for IceCube-Gen2 will be able to collect almost three times as much light as current optical sensors. Instead of a single-pixel sensor, they will use 24 pixels per sensor to detect light. About 400 of these state-of-the-art sensors will be produced for phase one of IceCube-Gen2, more than 200 of them in Germany. To increase the amount of usable light and the detectable signal, another variant of novel sensors use a new technique: Wavelength shifters slide the ultraviolet portion of the light to a wavelength that can permeate the glass containers of the sensors.

Sophisticated calibration methods

To further analyze the measured signals, it is crucial to understand in detail how light moves through the ice before being detected, and what the physical significance is of a particular signal as measured by the sensors. The IceCube team uses various calibration techniques to classify and measure both the general properties of the detector and the expected paths of light through the ice.

Artificial intelligence for neutrino searches

To classify a neutrino event as such, researchers have to put a lot of effort into comparing the light patterns of the measured signals with simulations. Simulations predict which signals to expect depending on the type of triggering event, the energy it emits, and the direction it comes from. They also take into account the properties of the glacial ice as known from the calibration data. Machine learning methods can significantly accelerate the analysis process, and quickly and reliably filter out neutrino events from the noise.

Help | Advanced Search

High Energy Physics - Experiment

Title: recent neutrino oscillation result with the icecube experiment.

Abstract: The IceCube South Pole Neutrino Observatory is a Cherenkov detector instrumented in a cubic kilometer of ice at the South Pole. IceCube's primary scientific goal is the detection of TeV neutrino emissions from astrophysical sources. At the lower center of the IceCube array, there is a subdetector called DeepCore, which has a denser configuration that makes it possible to lower the energy threshold of IceCube and observe GeV-scale neutrinos, opening the window to atmospheric neutrino oscillations studies. Advances in physics sensitivity have recently been achieved by employing Convolutional Neural Networks to reconstruct neutrino interactions in the DeepCore detector. In this contribution, the recent IceCube result from the atmospheric muon neutrino disappearance analysis using the CNN-reconstructed neutrino sample is presented and compared to the existing worldwide measurements.

Submission history

Access paper:.

• Other Formats

References & Citations

• INSPIRE HEP
• Google Scholar
• Semantic Scholar

BibTeX formatted citation

Bibliographic and Citation Tools

Code, data and media associated with this article, recommenders and search tools.

• Institution

arXivLabs: experimental projects with community collaborators

arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website.

Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them.

Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs .

Goddard Earth Sciences Division Projects

IceCube is a 3U CubeSat funded by NASA for spaceflight demonstration of a commercial 883-GHz cloud radiometer.  See this book chapter . IceCube Level 1 dataset is available for download here. The satellite has produced the first global atmospheric ice map at the 883-Gigahertz band, an important frequency in the submillimeter wavelength for studying cloud ice and its effect on Earth’s climate. The IceCube team is a winner of Robert H Goddard Exceptional Achievement  Award  for Engineering in 2019.

The first ever 883-GHz Cloud Ice Map.  For further details, see  https://www.nasa.gov/feature/goddard/2018/nasa-s-small-spacecraft-produces-first-883-gigahertz-global-ice-cloud-map

Deploying an IceCube

The IceCube payload team at Greenbelt include: (left photo, back row, from left to right): Dong Wu, Michael Solly, Jared Lucey, Jeffrey Piepmeier, Paul Racette, Derek Hudson; (front row, left to right): Melyane Ortiz-Acosta, Armi Pellerano, Carlos Duran-Aviles, Kevin Horgan, Negar Ehsan, and Mark Wong.

The spacecraft team at Wallops included (right photo, back row, from left to right): Chris Purdy, Brian Abresch, Alex Coleman, and Kurt Reddersen; (front row, from left to right): Brooks Flaherty, Scott Heatwole, Jerry Cote, Henry Hart, Bob Stancil, and Ted Daisey.

Earth IceCube

IceCube was successfully deployed from the ISS on May 16, 2016. It was contacted on its first pass over WFF about 73 minutes after the deployment. IceCube is operating and it was verified that both the solar arrays and antennas deployed and the battery is fully charged. It also appears that the ACS system is operating nominally.

883-GHz Cloud Radiometer

Clouds play an important role in Earth’s climate system through interactions with atmospheric radiation, dynamics, and precipitation processes. Global cloud ice and properties are critical for quantifying cloud’s roles, but it is challenging to measure these variables accurately. Submillimeter (submm) wave remote sensing has great capability of penetrating clouds and measuring ice mass and microphysical properties. The IceCube project, funded by NASA’s Science Mission Directorate (SMD) and Earth Science Technology Office (ESTO), is spaceflight demonstration of 883-GHz cloud radiometer on a 3U CubeSat. The 883-GHz frequency is a spectral window whereby the radiation is highly sensitive to ice cloud scattering and interacts in depth with volume ice mass inside the cloud. Built upon NASA’s ER-2 aircraft instrument, the Compact Scanning Submm-wave Imaging Radiometer (CoSSIR), the IceCube seeks to raise the technology readiness level (TRL) of 883-GHz radiometer for future spaceflight mission. Launched in May 2017, IceCube is a collaborative endeavor between NASA’s Goddard Space Flight Center (GSFC) and Virginia Diode Inc. (VDI).

IceCube was launched to the International Space Station (ISS) and subsequently released from ISS for nominal operation of 28+ days. The CubeSat will deploy the stowed solar panels on the long-side of the bus, and acquire the Sun shortly after released from ISS. The 883-GHz radiometer power will be cycled off during eclipse and on in daylight. The spacecraft is configured to spin continuously around the axis to the Sun at ~1.2 degrees per second. This spin allows the maximum solar power reception and periodic Earth and space views for instrument calibration. From the extended deep space and clear-sky nadir views, which are not available on the ground because of atmospheric opacity, the IceCube 883-GHz receiver will be validated against these stable references for its radiometric stability and accuracy.

Although IceCube is a technology demonstration experiment, it will acquire the first global 883 GHz cloud map from the cloud-induced radiance. These measurements will be used to assess ice cloud scattering strength and variability at this frequency for future cloud missions. A successful IceCube mission will also accelerate scientific exploration through efficient and frequent access to space with the CubeSat approach.

IceCube solar panel deployment was tested rigorously in laboratory as well as in a thermal vacuum chamber at NASA’s Wallops Flight Facility.

Celebrating IceCube’s first decade of discovery

It was the beginning of a grand experiment unlike anything the world had ever seen. Ten years ago today, the IceCube Neutrino Observatory fully opened its eyes for the first time.

Over the course of the previous seven years, dozens of intrepid technicians, engineers, and scientists had traveled to the South Pole—one of the coldest, driest, and most isolated places on Earth—to build the biggest, strangest telescope in the world. Crews drilled 86 holes nearly two-and-a-half kilometers deep and lowered a cable strung with 60 basketball-sized light detectors into each hole. The result was a hexagonal grid of sensors embedded in a cubic kilometer of ice about a mile below the surface of the Antarctic ice sheet. On December 18, 2010, the 5,160 th light sensor was deployed in the ice, completing the construction of the IceCube Neutrino Observatory.

The purpose of the unconventional telescope was to detect signals from passing astrophysical neutrinos: mysterious, tiny, extremely lightweight particles created by some of the most energetic and distant phenomena in the cosmos. IceCube’s founders believed that studying these astrophysical neutrinos would reveal hidden parts of the universe. Over the course of the next decade, they would be proven right.

IceCube began full operations on May 13, 2011—ten years ago today—when the detector took its first set of data as a completed instrument. Since then, IceCube has been watching the cosmos and collecting data continuously for a decade.

During its first few years of operation, IceCube accumulated vast amounts of data, but it wasn’t until 2013 that the observatory yielded its first major results. That year, the collaboration announced the first evidence for neutrinos from outside our galaxy with the detection of two very energetic neutrino events and, soon after, the observation of 26 additional very high energy events. Since then, we’ve seen more astrophysical neutrinos and have made strides in the fields of neutrino physics, astrophysics, and multimessenger astronomy. From pinpointing potential neutrino sources to the recent detection of a Glashow resonance event , IceCube has proven again and again the value of capturing perhaps the most elusive particles in the universe.

“The National Science Foundation took a dual gamble on IceCube related to the performance of the technology and the sensitivity of the instrument as a neutrino telescope,” said Francis Halzen, principal investigator of IceCube and professor at the University of Wisconsin–Madison, home of the Wisconsin IceCube Particle Astrophysics Center (WIPAC) where IceCube is headquartered. “The IceCube Collaboration has delivered a decade of data that continues to validate the high risk and high reward approach.”

This success has led to a growing cohort of scientists using state of the art techniques to analyze IceCube data. What started with a couple dozen dreamers is now the international IceCube Collaboration: a diverse group of over 350 scientists from 53 institutions in 12 countries across five continents. And we are actively working to inspire the next generation of physicists by bringing education and outreach activities to people of all ages and backgrounds. In the last decade, we have produced a web comic and translated it into 10 languages, created IceCube-themed arts and crafts , hosted countless South Pole webinars , supported multiple art installations , brought educators to the South Pole, and much more.

To celebrate this milestone with us, keep an eye on our website and social media profiles—we’re on Facebook , Twitter , Instagram , and YouTube —and follow the hashtag #IceCube10 . Over the next five months leading up to our fall collaboration meeting in September, we will share highlights from the past decade—and earlier!

There is also much to look forward to in IceCube’s bright future. The unusual instrument continues to expand its science reach, with leading results on neutrino properties, dark matter, cosmic rays, and fundamental physics. Though the pandemic has slightly altered the timeline, the National Science Foundation has provided funding for the next stage of our South Pole detector, the IceCube Upgrade , which will pave the way to the proposed larger, high-energy extension, IceCube-Gen2 .

While our 2021 celebrations will be mostly online, we hope we can continue the festivities in person sometime soon when we can gather safely. For now, thank you for joining us virtually to celebrate IceCube’s first decade of discovery!

The IceCube Neutrino Observatory is  funded  primarily by the National Science Foundation (OPP-1600823 and PHY-1913607) and is headquartered at the Wisconsin IceCube Particle Astrophysics Center, a research center of UW–Madison in the United States. IceCube’s research efforts, including critical contributions to the detector operation, are funded by agencies in Australia, Belgium, Canada, Denmark, Germany, Japan, New Zealand, Republic of Korea, Sweden, Switzerland, the United Kingdom, and the United States. The IceCube EPSCoR Initiative (IEI) also receives additional support through NSF-EPSCoR-2019597.   IceCube construction was also funded with significant contributions from the National Fund for Scientific Research (FNRS & FWO) in Belgium; the Federal Ministry of Education and Research (BMBF) and the German Research Foundation (DFG) in Germany; the Knut and Alice Wallenberg Foundation, the Swedish Polar Research Secretariat, and the Swedish Research Council in Sweden; and the University of Wisconsin–Madison Research Fund in the U.S.

Suggested Searches

Climate Change

• Expedition 64
• Mars perseverance
• SpaceX Crew-2
• International Space Station
• View All Topics A-Z

Humans in Space

Earth & Climate

The solar system, the universe, aeronautics, learning resources, news & events.

New NASA Sonifications Listen to the Universe’s Past

What’s Up: September 2024 Skywatching Tips from NASA

NASA Mission Gets Its First Snapshot of Polar Heat Emissions

• Search All NASA Missions
• A to Z List of Missions
• Upcoming Launches and Landings
• Spaceships and Rockets
• Communicating with Missions
• James Webb Space Telescope
• Hubble Space Telescope
• Why Go to Space
• Commercial Space
• Destinations
• Living in Space
• Explore Earth Science
• Earth, Our Planet
• Earth Science in Action
• Earth Multimedia
• Earth Science Researchers
• Pluto & Dwarf Planets
• Asteroids, Comets & Meteors
• The Kuiper Belt
• The Oort Cloud
• Skywatching
• The Search for Life in the Universe
• Black Holes
• The Big Bang
• Dark Energy & Dark Matter
• Earth Science
• Planetary Science
• Astrophysics & Space Science
• The Sun & Heliophysics
• Biological & Physical Sciences
• Lunar Science
• Citizen Science
• Astromaterials
• Aeronautics Research
• Human Space Travel Research
• Science in the Air
• NASA Aircraft
• Flight Innovation
• Supersonic Flight
• Air Traffic Solutions
• Green Aviation Tech
• Drones & You
• Technology Transfer & Spinoffs
• Space Travel Technology
• Technology Living in Space
• Manufacturing and Materials
• Science Instruments
• For Kids and Students
• For Educators
• For Colleges and Universities
• For Professionals
• Science for Everyone
• Requests for Exhibits, Artifacts, or Speakers
• STEM Engagement at NASA
• NASA's Impacts
• Centers and Facilities
• Directorates
• Organizations
• People of NASA
• Internships
• Our History
• Doing Business with NASA
• Get Involved

NASA en Español

• Aeronáutica
• Ciencias Terrestres
• Sistema Solar
• All NASA News
• Video Series on NASA+
• Newsletters
• Social Media
• Media Resources
• Upcoming Launches & Landings
• Virtual Guest Program
• Image of the Day
• Sounds and Ringtones
• Interactives
• STEM Multimedia

NASA Invites Social Creators to Experience Launch of Europa Clipper Mission

NASA’s Mini BurstCube Mission Detects Mega Blast

NASA, Boeing Optimizing Vehicle Assembly Building High Bay for Future SLS Stage Production

NASA Seeks Input for Astrobee Free-flying Space Robots

NASA Funds Studies to Support Crew Performance on Long-Duration Missions

NASA JPL Developing Underwater Robots to Venture Deep Below Polar Ice

NASA Project in Puerto Rico Trains Students in Marine Biology

NASA, ESA Missions Help Scientists Uncover How Solar Wind Gets Energy

September’s Night Sky Notes: Marvelous Moons

NASA’s Webb Reveals Distorted Galaxy Forming Cosmic Question Mark

Hubble Zooms into the Rosy Tendrils of Andromeda

Research Plane Dons New Colors for NASA Hybrid Electric Flight Tests 

NASA G-IV Plane Will Carry Next-Generation Science Instrument

NASA Develops Pod to Help Autonomous Aircraft Operators 

First NASA-Supported Researcher to Fly on Suborbital Rocket

How Do I Navigate NASA Learning Resources and Opportunities?

Carbon Nanotubes and the Search for Life on Other Planets

235 Years Ago: Herschel Discovers Saturn’s Moon Enceladus

La NASA invita a los medios al lanzamiento de Europa Clipper

El X-59 de la NASA avanza en las pruebas de preparación para volar

La NASA invita a creadores de las redes sociales al lanzamiento de la misión Europa Clipper

Jet propulsion laboratory, more about prefire, news media contacts.

The PREFIRE mission will help develop a more detailed understanding of how much heat the Arctic and Antarctica radiate into space and how this influences global climate.

NASA’s newest climate mission has started collecting data on the amount of heat in the form of far-infrared radiation that the Arctic and Antarctic environments emit to space. These measurements by the Polar Radiant Energy in the Far-Infrared Experiment ( PREFIRE ) are key to better predicting how climate change will affect Earth’s ice, seas, and weather — information that will help humanity better prepare for a changing world.

One of PREFIRE’s two shoebox-size cube satellites, or CubeSats, launched on May 25 from New Zealand, followed by its twin on June 5. The first CubeSat started sending back science data on July 1. The second CubeSat began collecting science data on July 25, and the mission will release the data after an issue with the GPS system on this CubeSat is resolved.

The PREFIRE mission will help researchers gain a clearer understanding of when and where the Arctic and Antarctica emit far-infrared radiation (wavelengths greater than 15 micrometers) to space. This includes how atmospheric water vapor and clouds influence the amount of heat that escapes Earth. Since clouds and water vapor can trap far-infrared radiation near Earth’s surface, they can increase global temperatures as part of a process known as the greenhouse effect . This is where gases in Earth’s atmosphere — such as carbon dioxide, methane, and water vapor — act as insulators, preventing heat emitted by the planet from escaping to space.

“We are constantly looking for new ways to observe the planet and fill in critical gaps in our knowledge. With CubeSats like PREFIRE, we are doing both,” said Karen St. Germain, director of the Earth Science Division at NASA Headquarters in Washington. “The mission, part of our competitively-selected Earth Venture program, is a great example of the innovative science we can achieve through collaboration with university and industry partners.”

Earth absorbs much of the Sun’s energy in the tropics; weather and ocean currents transport that heat toward the Arctic and Antarctica, which receive much less sunlight. The polar environment — including ice, snow, and clouds — emits a lot of that heat into space, much of which is in the form of far-infrared radiation. But those emissions have never been systematically measured, which is where PREFIRE comes in.

“It’s so exciting to see the data coming in,” said Tristan L’Ecuyer, PREFIRE’s principal investigator and a climate scientist at the University of Wisconsin, Madison. “With the addition of the far-infrared measurements from PREFIRE, we’re seeing for the first time the full energy spectrum that Earth radiates into space, which is critical to understanding climate change.”

This visualization of PREFIRE data (above) shows brightness temperatures — or the intensity of radiation emitted from Earth at several wavelengths, including the far-infrared. Yellow and red indicate more intense emissions originating from Earth’s surface, while blue and green represent lower emission intensities coinciding with colder areas on the surface or in the atmosphere.

The visualization starts by showing data on mid-infrared emissions (wavelengths between 4 to 15 micrometers) taken in early July during several polar orbits by the first CubeSat to launch. It then zooms in on two passes over Greenland. The orbital tracks expand vertically to show how far-infrared emissions vary through the atmosphere. The visualization ends by focusing on an area where the two passes intersect, showing how the intensity of far-infrared emissions changed over the nine hours between these two orbits.

The two PREFIRE CubeSats are in asynchronous, near-polar orbits, which means they pass over the same spots in the Arctic and Antarctic within hours of each other, collecting the same kind of data. This gives researchers a time series of measurements that they can use to study relatively short-lived phenomena like ice sheet melting or cloud formation and how they affect far-infrared emissions over time.

The PREFIRE mission was jointly developed by NASA and the University of Wisconsin-Madison. A division of Caltech in Pasadena, California, NASA’s Jet Propulsion Laboratory manages the mission for NASA’s Science Mission Directorate and provided the spectrometers. Blue Canyon Technologies built and now operates the CubeSats, and the University of Wisconsin-Madison is processing and analyzing the data collected by the instruments.

To learn more about PREFIRE, visit: https://science.nasa.gov/mission/prefire/

Jane J. Lee / Andrew Wang Jet Propulsion Laboratory, Pasadena, Calif. 818-354-0307 / 626-379-6874 [email protected] / [email protected]

Related Terms

• PREFIRE (Polar Radiant Energy in the Far-InfraRed Experiment)

Explore More

NASA Earth Science Education Collaborative Member Co-Authors Award-Winning Paper in Insects

On August 13, 2024, the publishers of the journal Insects notified authors of three papers…

Discover Related Topics

Solar System