Records |
Author |
Kasieczka, G. et al; Sanz, V. |
Title |
The LHC Olympics 2020: a community challenge for anomaly detection in high energy physics |
Type |
Journal Article |
Year |
2021 |
Publication |
Reports on Progress in Physics |
Abbreviated Journal |
Rep. Prog. Phys. |
Volume |
84 |
Issue |
12 |
Pages |
124201 - 64pp |
Keywords |
anomaly detection; machine learning; unsupervised learning; weakly supervised learning; semisupervised learning; beyond the standard model; model-agnostic methods |
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). 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. |
Address |
[Kasieczka, Gregor] Univ Hamburg, Inst Expt Phys, Hamburg, Germany, Email: gregor.kasieczka@uni-hamburg.de; |
Corporate Author |
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Thesis |
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Publisher |
IOP Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0034-4885 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000727698500001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5039 |
Permanent link to this record |
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Author |
Alekhin, S. et al; Hernandez, P. |
Title |
A facility to search for hidden particles at the CERN SPS: the SHiP physics case |
Type |
Journal Article |
Year |
2016 |
Publication |
Reports on Progress in Physics |
Abbreviated Journal |
Rep. Prog. Phys. |
Volume |
79 |
Issue |
12 |
Pages |
124201 - 137pp |
Keywords |
beyond the standard model physics; intensity frontier experiment; hidden sectors; heavy neutral leptons; dark photons |
Abstract |
This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (search for hidden particles) experiment is intended to hunt for new physics in the largely unexplored domain of very weakly interacting particles with masses below the Fermi scale, inaccessible to the LHC experiments, and to study tau neutrino physics. The same proton beam setup can be used later to look for decays of tau-leptons with lepton flavour number non-conservation, tau -> 3 μand to search for weakly-interacting sub-GeV dark matter candidates. We discuss the evidence for physics beyond the standard model and describe interactions between new particles and four different portals-scalars, vectors, fermions or axion-like particles. We discuss motivations for different models, manifesting themselves via these interactions, and how they can be probed with the SHiP experiment and present several case studies. The prospects to search for relatively light SUSY and composite particles at SHiP are also discussed. We demonstrate that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation. |
Address |
[Alekhin, Sergey] DESY, Platanenallee 6, D-15738 Zeuthen, Germany, Email: oleg.ruchayskiy@cern.ch |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0034-4885 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000387025400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2852 |
Permanent link to this record |
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Author |
Cheng, L.; Eberhardt, O.; Murphy, C.W. |
Title |
Novel theoretical constraints for color-octet scalar models |
Type |
Journal Article |
Year |
2019 |
Publication |
Chinese Physics C |
Abbreviated Journal |
Chin. Phys. C |
Volume |
43 |
Issue |
9 |
Pages |
093101 - 11pp |
Keywords |
beyond the Standard Model; extension of Higgs sector; EW symmetry breaking |
Abstract |
We study the theoretical constraints on a model whose scalar sector contains one color octet and one or two color singlet SU(2)(L) doublets. To ensure unitarity of the theory, we constrain the parameters of the scalar potential for the first time at the next-to-leading order in perturbation theory. Moreover, we derive new conditions guaranteeing the stability of the potential. We employ the HEPfit package to extract viable parameter regions at the electroweak scale and test the stability of the renormalization group evolution up to the multi-TeV region. Furthermore, we set upper limits on the scalar mass splittings. All results are given for both cases with and without a second scalar color singlet. |
Address |
[Cheng, Li] Inst Appl Phys & Computat Math, Beijing 100094, Peoples R China, Email: clmamuphy@sina.cn; |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1674-1137 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000482015900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4115 |
Permanent link to this record |
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Author |
Alimena, J. et al; Hirsch, M.; Mamuzic, J.; Mitsou, V.A.; Santra, A. |
Title |
Searching for long-lived particles beyond the Standard Model at the Large Hadron Collider |
Type |
Journal Article |
Year |
2020 |
Publication |
Journal of Physics G |
Abbreviated Journal |
J. Phys. G |
Volume |
47 |
Issue |
9 |
Pages |
090501 - 226pp |
Keywords |
beyond the Standard Model; long-lived particles; Large Hadron Collider; high-luminosity LHC; collider phenomenology; high-energy collider experiments |
Abstract |
Particles beyond the Standard Model (SM) can generically have lifetimes that are long compared to SM particles at the weak scale. When produced at experiments such as the Large Hadron Collider (LHC) at CERN, these long-lived particles (LLPs) can decay far from the interaction vertex of the primary proton-proton collision. Such LLP signatures are distinct from those of promptly decaying particles that are targeted by the majority of searches for new physics at the LHC, often requiring customized techniques to identify, for example, significantly displaced decay vertices, tracks with atypical properties, and short track segments. Given their non-standard nature, a comprehensive overview of LLP signatures at the LHC is beneficial to ensure that possible avenues of the discovery of new physics are not overlooked. Here we report on the joint work of a community of theorists and experimentalists with the ATLAS, CMS, and LHCb experiments-as well as those working on dedicated experiments such as MoEDAL, milliQan, MATHUSLA, CODEX-b, and FASER-to survey the current state of LLP searches at the LHC, and to chart a path for the development of LLP searches into the future, both in the upcoming Run 3 and at the high-luminosity LHC. The work is organized around the current and future potential capabilities of LHC experiments to generally discover new LLPs, and takes a signature-based approach to surveying classes of models that give rise to LLPs rather than emphasizing any particular theory motivation. We develop a set of simplified models; assess the coverage of current searches; document known, often unexpected backgrounds; explore the capabilities of proposed detector upgrades; provide recommendations for the presentation of search results; and look towards the newest frontiers, namely high-multiplicity 'dark showers', highlighting opportunities for expanding the LHC reach for these signals. |
Address |
[Alimena, Juliette; Hill, Christopher S.] Ohio State Univ, Dept Phys, 191 W Woodruff Ave, Columbus, OH 43210 USA, Email: juliette.alimena@cern.ch; |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0954-3899 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000570614200001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
4535 |
Permanent link to this record |
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Author |
Bordes, J.; Hong-Mo, C.; Tsun, T.S. |
Title |
The Z boson in the framed standard model |
Type |
Journal Article |
Year |
2018 |
Publication |
International Journal of Modern Physics A |
Abbreviated Journal |
Int. J. Mod. Phys. A |
Volume |
33 |
Issue |
32 |
Pages |
1850190 - 19pp |
Keywords |
Beyond the Standard Model; Z mixing; mass and decay of the electroweak gauge bosons; LHC phenomenology |
Abstract |
The framed standard model (FSM), constructed initially for explaining the existence of three fermion generations and the hierarchical mass and mixing patterns of quarks and leptons,(1,2) suggests also a “hidden sector” of particles(3) including some dark matter candidates. It predicts in addition a new vector boson G, with mass of order TeV, which mixes with the gamma and Z of the standard model yielding deviations from the standard mixing scheme, all calculable in terms of a single unknown parameter mG. Given that standard mixing has been tested already to great accuracy by experiment, this could lead to contradictions, but it is shown here that for the three crucial and testable cases so far studied (i) m(Z) – m(W), (ii) Gamma(Z -> l(+)l(-)), (iii) Gamma(Z -> hadrons), the deviations are all within the present stringent experimental bounds provided m(G) > 1 TeV, but should soon be detectable if experimental accuracy improves. This comes about because of some subtle cancellations, which might have a deeper reason that is not yet understood. By virtue of mixing, G can be produced at the LHC and appear as a l(+)l(-) anomaly. If found, it will be of interest not only for its own sake but serve also as a window on to the “hidden sector” into which it will mostly decay, with dark matter candidates as most likely products. |
Address |
[Bordes, Jose] Univ Valencia, Ctr Mixto CSIC, Dept Fis Teor, Calle Dr Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: bordes@uv.es; |
Corporate Author |
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Thesis |
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Publisher |
World Scientific Publ Co Pte Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0217-751x |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000451433900008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
3821 |
Permanent link to this record |