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Title: The LHC Olympics 2020 a community challenge for anomaly detection in high energy physics

Abstract

A new paradigm for data-driven, model-agnostic new physics searches at colliders is emerging, and aims to leverage recent breakthroughs in anomaly detection and machine learning. In order to develop and benchmark new anomaly detection methods within this framework, it is essential to have standard datasets. To this end, we have created the LHC Olympics 2020, a community challenge accompanied by a set of simulated collider events. Participants in these Olympics have developed their methods using an R&D dataset and then tested them on black boxes: datasets with an unknown anomaly (or not). Furthermore, methods made use of modern machine learning tools and were based on unsupervised learning (autoencoders, generative adversarial networks, normalizing flows), weakly supervised learning, and semi-supervised learning. This paper will review the LHC Olympics 2020 challenge, including an overview of the competition, a description of methods deployed in the competition, lessons learned from the experience, and implications for data analyses with future datasets as well as future colliders.

Authors:
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Publication Date:
Research Org.:
Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP)
Contributing Org.:
LHC Olympics Challenge Team
OSTI Identifier:
1909683
Alternate Identifier(s):
OSTI ID: 1863790; OSTI ID: 1867888
Grant/Contract Number:  
SC0011090; SC0012567; AC02-05CH11231; AC02-76SF00515
Resource Type:
Accepted Manuscript
Journal Name:
Reports on Progress in Physics
Additional Journal Information:
Journal Volume: 84; Journal Issue: 12; Journal ID: ISSN 0034-4885
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Kasieczka, Gregor, Nachman, Benjamin, Shih, David, Amram, Oz, Andreassen, Anders, Benkendorfer, Kees, Bortolato, Blaz, Brooijmans, Gustaaf, Canelli, Florencia, Collins, Jack H., Dai, Biwei, De Freitas, Felipe F., Dillon, Barry M., Dinu, Ioan-Mihail, Dong, Zhongtian, Donini, Julien, Duarte, Javier, Faroughy, D. A., Gonski, Julia, Harris, Philip, Kahn, Alan, Kamenik, Jernej F., Khosa, Charanjit K., Komiske, Patrick, Le Pottier, Luc, Martín-Ramiro, Pablo, Matevc, Andrej, Metodiev, Eric, Mikuni, Vinicius, Murphy, Christopher W., Ochoa, Inês, Park, Sang Eon, Pierini, Maurizio, Rankin, Dylan, Sanz, Veronica, Sarda, Nilai, Seljak, Urŏ, Smolkovic, Aleks, Stein, George, Suarez, Cristina Mantilla, Szewc, Manuel, Thaler, Jesse, Tsan, Steven, Udrescu, Silviu-Marian, Vaslin, Louis, Vlimant, Jean-Roch, Williams, Daniel, and Yunus, Mikaeel. The LHC Olympics 2020 a community challenge for anomaly detection in high energy physics. United States: N. p., 2021. Web. doi:10.1088/1361-6633/ac36b9.
Kasieczka, Gregor, Nachman, Benjamin, Shih, David, Amram, Oz, Andreassen, Anders, Benkendorfer, Kees, Bortolato, Blaz, Brooijmans, Gustaaf, Canelli, Florencia, Collins, Jack H., Dai, Biwei, De Freitas, Felipe F., Dillon, Barry M., Dinu, Ioan-Mihail, Dong, Zhongtian, Donini, Julien, Duarte, Javier, Faroughy, D. A., Gonski, Julia, Harris, Philip, Kahn, Alan, Kamenik, Jernej F., Khosa, Charanjit K., Komiske, Patrick, Le Pottier, Luc, Martín-Ramiro, Pablo, Matevc, Andrej, Metodiev, Eric, Mikuni, Vinicius, Murphy, Christopher W., Ochoa, Inês, Park, Sang Eon, Pierini, Maurizio, Rankin, Dylan, Sanz, Veronica, Sarda, Nilai, Seljak, Urŏ, Smolkovic, Aleks, Stein, George, Suarez, Cristina Mantilla, Szewc, Manuel, Thaler, Jesse, Tsan, Steven, Udrescu, Silviu-Marian, Vaslin, Louis, Vlimant, Jean-Roch, Williams, Daniel, & Yunus, Mikaeel. The LHC Olympics 2020 a community challenge for anomaly detection in high energy physics. United States. https://doi.org/10.1088/1361-6633/ac36b9
Kasieczka, Gregor, Nachman, Benjamin, Shih, David, Amram, Oz, Andreassen, Anders, Benkendorfer, Kees, Bortolato, Blaz, Brooijmans, Gustaaf, Canelli, Florencia, Collins, Jack H., Dai, Biwei, De Freitas, Felipe F., Dillon, Barry M., Dinu, Ioan-Mihail, Dong, Zhongtian, Donini, Julien, Duarte, Javier, Faroughy, D. A., Gonski, Julia, Harris, Philip, Kahn, Alan, Kamenik, Jernej F., Khosa, Charanjit K., Komiske, Patrick, Le Pottier, Luc, Martín-Ramiro, Pablo, Matevc, Andrej, Metodiev, Eric, Mikuni, Vinicius, Murphy, Christopher W., Ochoa, Inês, Park, Sang Eon, Pierini, Maurizio, Rankin, Dylan, Sanz, Veronica, Sarda, Nilai, Seljak, Urŏ, Smolkovic, Aleks, Stein, George, Suarez, Cristina Mantilla, Szewc, Manuel, Thaler, Jesse, Tsan, Steven, Udrescu, Silviu-Marian, Vaslin, Louis, Vlimant, Jean-Roch, Williams, Daniel, and Yunus, Mikaeel. Tue . "The LHC Olympics 2020 a community challenge for anomaly detection in high energy physics". United States. https://doi.org/10.1088/1361-6633/ac36b9. https://www.osti.gov/servlets/purl/1909683.
@article{osti_1909683,
title = {The LHC Olympics 2020 a community challenge for anomaly detection in high energy physics},
author = {Kasieczka, Gregor and Nachman, Benjamin and Shih, David and Amram, Oz and Andreassen, Anders and Benkendorfer, Kees and Bortolato, Blaz and Brooijmans, Gustaaf and Canelli, Florencia and Collins, Jack H. and Dai, Biwei and De Freitas, Felipe F. and Dillon, Barry M. and Dinu, Ioan-Mihail and Dong, Zhongtian and Donini, Julien and Duarte, Javier and Faroughy, D. A. and Gonski, Julia and Harris, Philip and Kahn, Alan and Kamenik, Jernej F. and Khosa, Charanjit K. and Komiske, Patrick and Le Pottier, Luc and Martín-Ramiro, Pablo and Matevc, Andrej and Metodiev, Eric and Mikuni, Vinicius and Murphy, Christopher W. and Ochoa, Inês and Park, Sang Eon and Pierini, Maurizio and Rankin, Dylan and Sanz, Veronica and Sarda, Nilai and Seljak, Urŏ and Smolkovic, Aleks and Stein, George and Suarez, Cristina Mantilla and Szewc, Manuel and Thaler, Jesse and Tsan, Steven and Udrescu, Silviu-Marian and Vaslin, Louis and Vlimant, Jean-Roch and Williams, Daniel and Yunus, Mikaeel},
abstractNote = {A new paradigm for data-driven, model-agnostic new physics searches at colliders is emerging, and aims to leverage recent breakthroughs in anomaly detection and machine learning. In order to develop and benchmark new anomaly detection methods within this framework, it is essential to have standard datasets. To this end, we have created the LHC Olympics 2020, a community challenge accompanied by a set of simulated collider events. Participants in these Olympics have developed their methods using an R&D dataset and then tested them on black boxes: datasets with an unknown anomaly (or not). Furthermore, methods made use of modern machine learning tools and were based on unsupervised learning (autoencoders, generative adversarial networks, normalizing flows), weakly supervised learning, and semi-supervised learning. This paper will review the LHC Olympics 2020 challenge, including an overview of the competition, a description of methods deployed in the competition, lessons learned from the experience, and implications for data analyses with future datasets as well as future colliders.},
doi = {10.1088/1361-6633/ac36b9},
journal = {Reports on Progress in Physics},
number = 12,
volume = 84,
place = {United States},
year = {Tue Dec 07 00:00:00 EST 2021},
month = {Tue Dec 07 00:00:00 EST 2021}
}

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