| Records |
| Author |
ATLAS Collaboration (Aad, G. et al); Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Cardillo, F.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Mamuzic, J.; Marti-Garcia, S.; Martinez Agullo, P.; Mitsou, V.A.; Moreno Llacer, M.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Sayago Galvan, I.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M. |
| Title |
The ATLAS Fast TracKer system |
Type |
Journal Article |
| Year |
2021 |
Publication  |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
16 |
Issue |
7 |
Pages |
P07006 - 61pp |
| Keywords |
Modular electronics; Online farms and online filtering; Pattern recognition, cluster finding, calibration and fitting methods; Trigger concepts and systems (hardware and software) |
| Abstract |
The ATLAS Fast TracKer (FTK) was designed to provide full tracking for the ATLAS high-level trigger by using pattern recognition based on Associative Memory (AM) chips and fitting in high-speed field programmable gate arrays. The tracks found by the FTK are based on inputs from all modules of the pixel and silicon microstrip trackers. The as-built FTK system and components are described, as is the online software used to control them while running in the ATLAS data acquisition system. Also described is the simulation of the FTK hardware and the optimization of the AM pattern banks. An optimization for long-lived particles with large impact parameter values is included. A test of the FTK system with the data playback facility that allowed the FTK to be commissioned during the shutdown between Run 2 and Run 3 of the LHC is reported. The resulting tracks from part of the FTK system covering a limited eta-phi region of the detector are compared with the output from the FTK simulation. It is shown that FTK performance is in good agreement with the simulation. |
| Address |
[Duvnjak, D.; Jackson, P.; Kong, A. X. Y.; Oliver, J. L.; Ruggeri, T. A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
| 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 Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
1748-0221 |
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:000791152800006 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5225 |
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| Author |
ATLAS Collaboration (Aad, G. et al); Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Costa, M.J.; Didenko,, M.; Escobar, C.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M. |
| Title |
Tools for estimating fake/non-prompt lepton backgrounds with the ATLAS detector at the LHC |
Type |
Journal Article |
| Year |
2023 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
18 |
Issue |
11 |
Pages |
T11004 - 61pp |
| Keywords |
Analysis and statistical methods; Particle identification methods |
| Abstract |
Measurements and searches performed with the ATLAS detector at the CERN LHC often involve signatures with one or more prompt leptons. Such analyses are subject to 'fake/non-prompt' lepton backgrounds, where either a hadron or a lepton from a hadron decay or an electron from a photon conversion satisfies the prompt-lepton selection criteria. These backgrounds often arise within a hadronic jet because of particle decays in the showering process, particle misidentification or particle interactions with the detector material. As it is challenging to model these processes with high accuracy in simulation, their estimation typically uses data-driven methods. Three methods for carrying out this estimation are described, along with their implementation in ATLAS and their performance. |
| Address |
[Amerl, M.; Filmer, E. K.; Jackson, P.; Kong, A. X. Y.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
| 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 |
1748-0221 |
ISBN |
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Medium |
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| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:001116977400001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5884 |
| Permanent link to this record |
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| Author |
ATLAS Collaboration (Aad, G. et al); Akiot, A.; Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Chitishvili, M.; Costa, M.J.; Didenko,, M.; Escobar, C.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Lacasta, C.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valiente Moreno, E.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M. |
| Title |
Fast b-tagging at the high-level trigger of the ATLAS experiment in LHC Run 3 |
Type |
Journal Article |
| Year |
2023 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
18 |
Issue |
11 |
Pages |
P11006 - 38pp |
| Keywords |
Trigger algorithms; Trigger concepts and systems (hardware and software) |
| Abstract |
The ATLAS experiment relies on real-time hadronic jet reconstruction and b-tagging to record fully hadronic events containing b-jets. These algorithms require track reconstruction, which is computationally expensive and could overwhelm the high-level-trigger farm, even at the reduced event rate that passes the ATLAS first stage hardware-based trigger. In LHC Run 3, ATLAS has mitigated these computational demands by introducing a fast neural-network-based b-tagger, which acts as a low-precision filter using input from hadronic jets and tracks. It runs after a hardware trigger and before the remaining high-level-trigger reconstruction. This design relies on the negligible cost of neural-network inference as compared to track reconstruction, and the cost reduction from limiting tracking to specific regions of the detector. In the case of Standard Model HH -> b (b) over barb (b) over bar, a key signature relying on b-jet triggers, the filter lowers the input rate to the remaining high-level trigger by a factor of five at the small cost of reducing the overall signal efficiency by roughly 2%. |
| Address |
[Filmer, E. K.; Grant, C. M.; Jackson, P.; Kong, A. X. Y.; Pandya, H. D.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
| 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 |
1748-0221 |
ISBN |
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Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:001123791900004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5972 |
| Permanent link to this record |
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| |
| Author |
ATLAS Collaboration (Aad, G. et al); Aikot, A.; Amos, K.R.; Aparisi Pozo, J.A.; Bailey, A.J.; Bouchhar, N.; Cabrera Urban, S.; Cantero, J.; Cardillo, F.; Castillo Gimenez, V.; Chitishvili, M.; Costa, M.J.; Didenko, M.; Escobar, C.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gomez Delegido, A.J.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Lacasta, C.; Marti-Garcia, S.; Martinez Agullo, P.; Miralles Lopez, M.; Mitsou, V.A.; Monsonis Romero, L.; Moreno Llacer, M.; Munoz Perez, D.; Navarro-Gonzalez, J.; Poveda, J.; Prades Ibañez, A.; Rubio Jimenez, A.; Ruiz-Martinez, A.; Sabatini, P.; Saibel, A.; Salt, J.; Sanchez Sebastian, V.; Sayago Galvan, I.; Senthilkumar, V.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valiente Moreno, E.; Valls Ferrer, J.A.; Varriale, L.; Villaplana Perez, M.; Vos, M. |
| Title |
Electron and photon energy calibration with the ATLAS detector using LHC Run 2 data |
Type |
Journal Article |
| Year |
2024 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
19 |
Issue |
2 |
Pages |
P02009 - 58pp |
| Keywords |
Calorimeter methods; Pattern recognition; cluster finding; calibration and fitting methods; Performance of High Energy Physics Detectors |
| Abstract |
This paper presents the electron and photon energy calibration obtained with the ATLAS detector using 140 fb-1 of LHC proton -proton collision data recorded at -Js = 13 TeV between 2015 and 2018. Methods for the measurement of electron and photon energies are outlined, along with the current knowledge of the passive material in front of the ATLAS electromagnetic calorimeter. The energy calibration steps are discussed in detail, with emphasis on the improvements introduced in this paper. The absolute energy scale is set using a large sample of Z -boson decays into electron -positron pairs, and its residual dependence on the electron energy is used for the first time to further constrain systematic uncertainties. The achieved calibration uncertainties are typically 0.05% for electrons from resonant Z -boson decays, 0.4% at ET – 10 GeV, and 0.3% at ET – 1 TeV; for photons at ET <^>' 60 GeV, they are 0.2% on average. This is more than twice as precise as the previous calibration. The new energy calibration is validated using .11tfr -, ee and radiative Z -boson decays. |
| Address |
[Filmer, E. K.; Grant, C. M.; Jackson, P.; Kong, A. X. Y.; Pandya, H. D.; Potti, H.; Ruggeri, T. A.; Ting, E. X. L.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
| 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 |
1748-0221 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:001185791500005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
6069 |
| Permanent link to this record |
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| Author |
Altheimer, A. et al; Villaplana Perez, M.; Vos, M. |
| Title |
Jet substructure at the Tevatron and LHC: new results, new tools, new benchmarks |
Type |
Journal Article |
| Year |
2012 |
Publication |
Journal of Physics G |
Abbreviated Journal |
J. Phys. G |
| Volume |
39 |
Issue |
6 |
Pages |
063001 - 44pp |
| Keywords |
|
| Abstract |
In this paper, we review recent theoretical progress and the latest experimental results in jet substructure from the Tevatron and the LHC. We review the status of and outlook for calculation and simulation tools for studying jet substructure. Following up on the report of the Boost 2010 workshop, we present a new set of benchmark comparisons of substructure techniques, focusing on the set of variables and grooming methods that are collectively known as 'top taggers'. To facilitate further exploration, we have attempted to collect, harmonize and publish software implementations of these techniques. |
| Address |
[Altheimer, A.; Brooijmans, G.; Cholakian, A. E.] Columbia Univ, Nevis Lab, Irvington, NY 10533 USA, Email: lasquith@hep.anl.gov; |
| 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:000304187900001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
1031 |
| Permanent link to this record |
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| |
| Author |
ATLAS Collaboration (Aad, G. et al); Amoros, G.; Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Ferrer, A.; Fuster, J.; Garcia, C.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Miñano, M.; Mitsou, V.A.; Moles-Valls, R.; Moreno Llacer, M.; Oliver Garcia, E.; Perez Garcia-Estañ, M.T.; Ros, E.; Salt, J.; Solans, C.A.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.; Wildauer, A. |
| Title |
Measurement of the inelastic proton-proton cross-section at sqrt(s)=7 TeV with the ATLAS detector |
Type |
Journal Article |
| Year |
2011 |
Publication |
Nature Communications |
Abbreviated Journal |
Nat. Commun. |
| Volume |
2 |
Issue |
|
Pages |
463 - 14pp |
| Keywords |
|
| Abstract |
The dependence of the rate of proton-proton interactions on the centre-of-mass collision energy, root s, is of fundamental importance for both hadron collider physics and particle astrophysics. The dependence cannot yet be calculated from first principles; therefore, experimental measurements are needed. Here we present the first measurement of the inelastic proton-proton interaction cross-section at a centre-of-mass energy, root s, of 7 TeV using the ATLAS detector at the Large Hadron Collider. Events are selected by requiring hits on scintillation counters mounted in the forward region of the detector. An inelastic crosssection of 60.3 +/- 2.1 mb is measured for xi > 5x10(-6), where xi is calculated from the invariant mass, M(X), of hadrons selected using the largest rapidity gap in the event. For diffractive events, this corresponds to requiring at least one of the dissociation masses to be larger than 15.7 GeV. |
| Address |
[Bechtle, P; Kuutmann, EB; Boehler, M; Ehrenfeld, W; Ferrara, V; Fischer, G; Glazov, A; Goebel, M; Fajardo, LSG; Da Costa, JGPF; Gosdzik, B; Gregor, IM; Hiller, KH; Hristova, I; Husemann, U; Belenguer, MJ; Johnert, S; Karnevskiy, M; Katzy, J; Kono, T; Lankford, AJ; Lobodzinska, E; Ludwig, D; Mattig, S; Medinnis, M; Mijovic, L; Monig, K; Naumann, T; Nozicka, M; Cavalcanti, TP; Petschull, D; Piec, SM; Placakyte, R; Qin, Z; Rubinskiy, I; Stelzer, HJ; Tackmann, K; Terwort, M; Vankov, P; Viti, M; Wildt, MA; Zhu, H] DESY, D-2000 Hamburg, Germany, Email: atlas.publications@cern.ch |
| Corporate Author |
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Thesis |
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| Publisher |
Nature Publishing Group |
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 |
|
Series Issue |
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Edition |
|
| ISSN |
2041-1723 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000294807200005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ elepoucu @ |
Serial |
758 |
| Permanent link to this record |
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| Author |
ATLAS Collaboration (Aaboud, M. et al); Alvarez Piqueras, D.; Barranco Navarro, L.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Higon-Rodriguez, E.; Jimenez Pena, J.; Lacasta, C.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Mitsou, V.A.; Pedraza Lopez, S.; Rodriguez Rodriguez, D.; Romero Adam, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
| Title |
Evidence for light-by-light scattering in heavy-ion collisions with the ATLAS detector at the LHC |
Type |
Journal Article |
| Year |
2017 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat. Phys. |
| Volume |
13 |
Issue |
9 |
Pages |
852-858 |
| Keywords |
|
| Abstract |
Light-by-light scattering (gamma gamma -> gamma gamma) is a quantum-mechanical process that is forbidden in the classical theory of electrodynamics. This reaction is accessible at the Large Hadron Collider thanks to the large electromagnetic field strengths generated by ultra-relativistic colliding lead ions. Using 480 μb(-1) of lead-lead collision data recorded at a centre-of-mass energy per nucleon pair of 5.02 TeV by the ATLAS detector, here we report evidence for light-by-light scattering. A total of 13 candidate events were observed with an expected background of 2.6 +/- 0.7 events. After background subtraction and analysis corrections, the fiducial cross-section of the process Pb + Pb (gamma gamma) -> Pb-(center dot) + Pb-(center dot) gamma gamma, for photon transverse energy E-T > 3 GeV, photon absolute pseudorapidity vertical bar eta vertical bar < 2.4, diphoton invariant mass greater than 6 GeV, diphoton transverse momentum lower than 2 GeV and diphoton acoplanarity below 0.01, is measured to be 70 +/- 24 (stat.) +/- 17 (syst.) nb, which is in agreement with the standard model predictions. |
| Address |
[Jackson, P.; Lee, L.; Petridis, A.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia |
| Corporate Author |
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Thesis |
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| Publisher |
Nature Publishing Group |
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 |
|
Series Issue |
|
Edition |
|
| ISSN |
1745-2473 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000409235100017 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
3287 |
| Permanent link to this record |
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| |
| Author |
ATLAS Collaboration (Aad, G. et al); Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Cardillo, F.; Castillo, F.L.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Mamuzic, J.; Marti-Garcia, S.; Martinez Agullo, P.; Mitsou, V.A.; Moreno Llacer, M.; Poveda, J.; Prades Ibañez, A.; Rodriguez Bosca, S.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Santra, A.; Sayago Galvan, I.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M. |
| Title |
Search for charged-lepton-flavour violation in Z-boson decays with the ATLAS detector |
Type |
Journal Article |
| Year |
2021 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat. Phys. |
| Volume |
17 |
Issue |
|
Pages |
819-825 |
| Keywords |
|
| Abstract |
Leptons with essentially the same properties apart from their mass are grouped into three families (or flavours). The number of leptons of each flavour is conserved in interactions, but this is not imposed by fundamental principles. Since the formulation of the standard model of particle physics, the observation of flavour oscillations among neutrinos has shown that lepton flavour is not conserved in neutrino weak interactions. So far, there has been no experimental evidence that this also occurs in interactions between charged leptons. Such an observation would be a sign of undiscovered particles or a yet unknown type of interaction. Here the ATLAS experiment at the Large Hadron Collider at CERN reports a constraint on lepton-flavour-violating effects in weak interactions, searching for Z-boson decays into a tau lepton and another lepton of different flavour with opposite electric charge. The branching fractions for these decays are measured to be less than 8.1 x 10(-6) (e tau) and 9.5 x 10(-6) (mu tau) at the 95% confidence level using 139 fb(-1) of proton-proton collision data at a centre-of-mass energy of root s = 13 TeV and 20.3 fb(-1) at root s = 8 TeV. These results supersede the limits from the Large Electron-Positron Collider experiments conducted more than two decades ago. |
| Address |
[Aad, G.; Barbero, M.; Bartolini, G.; Calvet, T. P.; Coadou, Y.; Diaconu, C.; Djama, F.; Duperrin, A.; Feligioni, L.; Fortin, E.; Guo, Z.; Hallewell, G. D.; Hubaut, F.; Knoops, E. B. F. G.; Le Guirriec, E.; Monnier, E.; Muanza, S.; Nagy, E.; Nguyen, H. D. N.; Petit, E.; Pralavorio, P.; Rozanov, A.; Strebler, T.; Talby, M.; Tisserant, S.; Toth, J.; Vu, N. K.] Aix Marseille Univ, CNRS, IN2P3, CPPM, Marseille, France, Email: atlas.publications@cern.ch |
| Corporate Author |
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Thesis |
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| Publisher |
Nature Research |
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 |
1745-2473 |
ISBN |
|
Medium |
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| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000668820400003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4892 |
| Permanent link to this record |
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| Author |
ATLAS Collaboration (Aad, G. et al); Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Cardillo, F.; Castillo, F.L.; Castillo Gimenez, V.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Martinez Agullo, P.; Mitsou, V.A.; Moreno Llacer, M.; Poveda, J.; Prades Ibañez, A.; Rodriguez Bosca, S.; Ruiz-Martinez, A.; Sabatini, P.; Salt, J.; Santra, A.; Sayago Galvan, I.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
| Title |
Test of the universality of τ and μ lepton couplings in W-boson decays with the ATLAS detector |
Type |
Journal Article |
| Year |
2021 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat. Phys. |
| Volume |
17 |
Issue |
|
Pages |
813-818 |
| Keywords |
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| Abstract |
The standard model of particle physics encapsulates our best current understanding of physics at the smallest scales. A fundamental axiom of this theory is the universality of the couplings of the different generations of leptons to the electroweak gauge bosons. The measurement of the ratio of the decay rate of W bosons to t leptons and muons, R(tau/mu), constitutes an important test of this axiom. Using 139 fb(-1) of proton-proton collisions recorded with the ATLAS detector at a centre-of-mass energy of 13 TeV, we report a measurement of this quantity from di-leptonic tt events where the top quarks decay into a W boson and a bottom quark. We can distinguish muons originating from W bosons and those originating from an intermediate t lepton through the muon transverse impact parameter and differences in the muon transverse momentum spectra. The measured value of R(tau/mu) is 0.992 +/- 0.013 [+/- 0.007(stat) +/- 0.011(syst)] and is in agreement with the hypothesis of universal lepton couplings as postulated in the standard model. This is the only such measurement from the Large Hadron Collider, so far, and obtains twice the precision of previous measurements. |
| Address |
[Aad, G.; Barbero, M.; Bartolini, G.; Calvet, T. P.; Coadou, Y.; Diaconu, C.; Djama, F.; Duperrin, A.; Feligioni, L.; Fortin, E.; Guo, Z.; Hallewell, G. D.; Hubaut, F.; Knoops, E. B. F. G.; Le Guirriec, E.; Monnier, E.; Muanza, S.; Nagy, E.; Nguyen, H. D. N.; Petit, E.; Pralavorio, P.; Rozanov, A.; Strebler, T.; Talby, M.; Tisserant, S.; Toth, J.; Vu, N. K.] Aix Marseille Univ, CPPM, CNRS IN2P3, Marseille, France |
| Corporate Author |
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Thesis |
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| Publisher |
Nature Research |
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 |
|
| ISSN |
1745-2473 |
ISBN |
|
Medium |
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| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000669764700003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
4895 |
| Permanent link to this record |
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| Author |
ATLAS Collaboration (Aad, G. et al); Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Castillo, F.L.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Miñano, M.; Mitsou, V.A.; Moreno Llacer, M.; Rodriguez Bosca, S.; Rodriguez Rodriguez, D.; Ruiz-Martinez, A.; Salt, J.; Santra, A.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M. |
| Title |
Observation of electroweak production of two jets and a Z-boson pair |
Type |
Journal Article |
| Year |
2023 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat. Phys. |
| Volume |
19 |
Issue |
2 |
Pages |
237-253 |
| Keywords |
|
| Abstract |
Electroweak symmetry breaking explains the origin of the masses of elementary particles through their interactions with the Higgs field. Besides the measurements of the Higgs boson properties, the study of the scattering of massive vector bosons with spin 1 allows the nature of electroweak symmetry breaking to be probed. Among all processes related to vector-boson scattering, the electroweak production of two jets and a Z-boson pair is a rare and important one. Here we report the observation of this process from proton-proton collision data corresponding to an integrated luminosity of 139fb(-1) recorded at a centre-of-mass energy of 13TeV with the ATLAS detector at the Large Hadron Collider. We consider two different final states originating from the decays of the Z-boson pair: one containing four charged leptons and another containing two charged leptons and two neutrinos. The hypothesis of no electroweak production is rejected with a statistical significance of 5.7 sigma, and the measured cross-section for electroweak production is consistent with the Standard Model prediction. In addition, we report cross-sections for inclusive production of a Z-boson pair and two jets for the two final states. |
| Address |
[Aad, G.; Barbero, M.; Bartolini, G.; Brahimi, N.; Calandri, A.; Coadou, Y.; Corga, K. De Vasconcelos; Diaconu, C.; Djama, F.; Duperrin, A.; El Kosseifi, R.; Feligioni, L.; Guo, Z.; Hallewell, G. D.; Hubaut, F.; Knoops, E. B. F. G.; Kukla, R.; Le Guirriec, E.; Monnier, E.; Muanza, S.; Nagy, E.; Nguyen, H. D. N.; Petit, E.; Pralavorio, P.; Rozanov, A.; Talby, M.; Tisserant, S.; Toth, J.; Wolff, R.] Aix Marseille Univ, CPPM, CNRS, IN2P3, Marseille, France, Email: atlas.publications@cern.ch |
| Corporate Author |
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Thesis |
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| Publisher |
Nature Portfolio |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1745-2473 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:001005403200001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5598 |
| Permanent link to this record |
