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Author Boggia, M.; Cruz-Martinez, J.M.; Frellesvig, H.; Glover, N.; Gomez-Ambrosio, R.; Gonella, G.; Haddad, Y.; Ilnicka, A.; Jones, S.; Kassabov, Z.; Krauss, F.; Megy, T.; Melini, D.; Napoletano, D.; Passarino, G.; Patel, S.; Rodriguez-Vazquez, M.; Wolf, T.
Title The HiggsTools handbook: a beginners guide to decoding the Higgs sector Type Journal Article
Year 2018 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 45 Issue (down) 6 Pages 065004 - 152pp
Keywords LHC physics; Higgs boson; new physics searches; effective field theories; Higgs momentum distributions
Abstract This report summarises some of the activities of the HiggsTools initial training network working group in the period 2015-2017. The main goal of this working group was to produce a document discussing various aspects of state-of-the-art Higgs physics at the large hadron collider (LHC) in a pedagogic manner The first part of the report is devoted to a description of phenomenological searches for new physics (NP) at the LHC. All of the available studies of the couplings of the new resonance discovered in 2012 by the ATLAS and CMS experiments (Aad et al (ATLAS Collaboration) 2012 Phys. Lett. B 716 1-29; Chatrchyan et al (CMS Collaboration) 2012 Phys. Lett. B 716 30-61) conclude that it is compatible with the Higgs boson of the standard model (SM) within present precision. So far the LHC experiments have given no direct evidence for any physical phenomena that cannot be described by the SM. As the experimental measurements become more and more precise, there is a pressing need for a consistent framework in which deviations from the SM predictions can be computed precisely. Such a framework should be applicable to measurements in all sectors of particle physics, not only LHC Higgs measurements but also electroweak precision data, etc. We critically review the use of the k-framework, fiducial and simplified template cross sections, effective field theories, pseudoobservables and phenomenological Lagrangians. Some of the concepts presented here are well known and were used already at the time of the large electron-positron collider (LEP) experiment. However, after years of theoretical and experimental development, these techniques have been refined, and we describe new tools that have been introduced in order to improve the comparison between theory and experimental data. In the second part of the report, we propose Phi(eta)* as a new and complementary observable for studying Higgs boson production at large transverse momentum in the case where the Higgs boson decays to two photons. The Phi(eta)* variable depends on measurements of the angular directions and rapidities of the two Higgs decay products rather than the energies, and exploits the information provided by the calorimeter in the detector. We show that, even without tracking information, the experimental resolution for Phi(eta)* is better than that of the transverse momentum of the photon pair, particularly at low transverse momentum. We make a detailed study of the phenomenology of the Phi(eta)* variable, contrasting the behaviour with the Higgs transverse momentum distribution using a variety of theoretical tools including event generators and fixed order perturbative computations. We consider the theoretical uncertainties associated with both p TH and Phi(eta)* distributions. Unlike the transverse momentum distribution, the Phi(eta)* distribution is well predicted using the Higgs effective field theory in which the top quark is integrated out-even at large values of Phi(eta)*-thereby making this a better observable for extracting the parameters of the Higgs interaction. In contrast, the potential of the Phi(eta)* distribution as a probe of NP is rather limited, since although the overall rate is affected by the presence of additional heavy fields, the shape of the Phi(eta)* distribution is relatively insensitive to heavy particle thresholds.
Address [Boggia, M.; Gonella, G.; Jones, S.; Megy, T.] Albert Ludwigs Univ Freiburg, Phys Inst, D-79104 Freiburg, Germany, Email: raquel.gomez-ambrosio@durham.ac.uk
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0954-3899 ISBN Medium
Area Expedition Conference
Notes WOS:000434094000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3604
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Author ATLAS Collaboration (Aad, G. et al); Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Fassi, F.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Kaci, M.; Lacasta, C.; Lacuesta, V.R.; March, L.; Marti-Garcia, S.; Miñano, M.; Mitsou, V.A.; Moles-Valls, R.; Moreno Llacer, M.; Oliver Garcia, E.; Pedraza Lopez, S.; Perez Garcia-Estañ, M.T.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Solans, C.A.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.
Title Search for supersymmetry in events with photons, bottom quarks, and missing transverse momentum in proton-proton collisions at a centre-of-mass energy of 7 TeV with the ATLAS detector Type Journal Article
Year 2013 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 719 Issue (down) 4-5 Pages 261-279
Keywords Supersymmetry; Gauge mediation; Higgs boson
Abstract A search has been performed for the experimental signature of an isolated photon with high transverse momentum, at least one jet identified as originating from a bottom quark, and high missing transverse momentum. Such a final state may originate from supersymmetric models with gauge-mediated supersymmetry breaking in events in which one of a pair of higgsino-like neutralinos decays into a photon and a gravitino while the other decays into a Higgs boson and a gravitino. The search is performed using the full dataset of 7 TeV proton-proton collisions recorded with the ATLAS detector at the LHC in 2011, corresponding to an integrated luminosity of 4.7 fb(-1). A total of 7 candidate events are observed while 7.5 +/- 2.2 events are expected from the Standard Model background. The results of the search are interpreted in the context of general gauge mediation to exclude certain regions of a benchmark plane for higgsino-like neutralino production.
Address [Jackson, P.; Soni, N.] Univ Adelaide, Sch Chem & Phys, Adelaide, SA, Australia
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000315316900006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1374
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Author ALEPH, DELPHI, L3 and OPAL Collaborations, LEP Electroweak Working Group (Schael, S. et al); Costa, M.J.; Ferrer, A.; Fuster, J.; Garcia, C.; Oyanguren, A.; Perepelitsa, V.; Salt, J.; Tortosa, P.
Title Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP Type Journal Article
Year 2013 Publication Physics Reports Abbreviated Journal Phys. Rep.
Volume 532 Issue (down) 4 Pages 119-244
Keywords Electron-positron physics; Electroweak interactions; Decays of heavy intermediate gauge bosons; Fermion-antifermion production; Precision measurements at W-pair energies; Tests of the Standard Model; Radiative corrections; Effective coupling constants; Neutral weak current; Z boson; W boson; Top quark; Higgs boson
Abstract Electroweak measurements performed with data taken at the electron positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb(-1) collected by the four LEP experiments ALEPH, DELPHI, 13 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose Einstein correlations between the two W decay systems arising in WW production, are searched for and upper limits on the strength of possible effects are obtained. The data are used to determine fundamental properties of the W boson and the electroweak theory. Among others, the mass and width of the W boson, m(w) and Gamma(w), the branching fraction of W decays to hadrons, B(W -> had), and the trilinear gauge-boson self-couplings g(1)(Z), K-gamma and lambda(gamma), are determined to be: m(w) = 80.376 +/- 0.033 GeV Gamma(w) = 2.195 +/- 0.083 GeV B(W -> had) = 67.41 +/- 0.27% g(1)(Z) = 0.984(-0.020)(+0.018) K-gamma – 0.982 +/- 0.042 lambda(gamma) = 0.022 +/- 0.019.
Address [Schael, S.] Rhein Westfal TH Aachen, Inst Phys, D-52056 Aachen, Germany
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-1573 ISBN Medium
Area Expedition Conference
Notes WOS:000328723800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1679
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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.; Fiorini, L.; 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 Search for neutral MSSM Higgs bosons decaying to tau(+)tau(-) pairs in proton-proton collisions sqrt(s)=7 TeV with the ATLAS detector Type Journal Article
Year 2011 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 705 Issue (down) 3 Pages 174-192
Keywords Higgs boson; MSSM; Tau lepton
Abstract A search for neutral Higgs bosons decaying to pairs of tau leptons with the ATLAS detector at the LHC is presented. The analysis is based on proton-proton collisions at a center-of-mass energy of 7 TeV, recorded in 2010 and corresponding to an integrated luminosity of 36 pb(-1). After signal selection, 276 events are observed in this data sample. The observed number of events is consistent with the total expected background of 269 +/- 36 events. Exclusion limits at the 95% confidence level are derived for the production cross section of a generic Higgs boson phi as a function of the Higgs boson mass and for A/H/h production in the Minimal Supersymmetric Standard Model (MSSM) as a function of the parameters m(A) and tan beta.
Address [Aad, G; Ahles, F; Beckingham, M; Bernhard, R; Bitenc, U; Bruneliere, R; Caron, S; Christov, A; Consorti, V; Eckert, S; Fehling-Kaschek, M; Flechl, M; Glatzer, J; Hartert, J; Herten, G; Horner, S; Jakobs, K; Ketterer, C; Kollefrath, M; Kononov, AI; Kuehn, S; Lai, S; Landgraf, U; Lohwasser, K; Ludwig, I; Ludwig, J; Lumb, D; Mahboubi, K; Meinhardt, J; Mohr, W; Nilsen, H; Parzefall, U; Rammensee, M; Runge, K; Rurikova, Z; Schillo, C; Schmidt, E; Schumacher, M; Siegert, F; Stoerig, K; Sundermann, JE; Temming, KK; Thoma, S; Tobias, J; Tsiskaridze, V; Venturi, M; Vivarelli, I; von Radziewski, H; Warsinsky, M; Weiser, C; Werner, M; Wiik, LAM; Winkelmann, S; Xie, S; Zimmermann, S] Univ Freiburg, Fak Math & Phys, Freiburg, Germany
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000297180700004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 822
Permanent link to this record
 

 
Author ATLAS Collaboration (Aad, G. et al); Cabrera Urban, S.; Castillo Gimenez, V.; Costa, M.J.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; 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.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Solans, C.A.; Soldevila, U.; Sanchez, J.; Torro Pastor, E.; Valero, A.; Valladolid Gallego, E.; Valls Ferrer, J.A.; Villaplana Perez, M.; Vos, M.; Wildauer, A.
Title Search for the Standard Model Higgs boson produced in association with a vector boson and decaying to a b-quark pair with the ATLAS detector Type Journal Article
Year 2012 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 718 Issue (down) 2 Pages 369-390
Keywords Standard Model Higgs boson; ATLAS; LHC
Abstract This Letter presents the results of a direct search with the ATLAS detector at the LHC for a Standard Model Higgs boson of mass 110 <= m(H) <= 130 GeV produced in association with a W or Z boson and decaying to b (b) over bar. Three decay channels are considered: ZH -> l(+)l(-)b (b) over bar, WH -> lvbb (b) over bar and ZH -> v (v) over bar(b) over bar where l corresponds to an electron or a muon. No evidence for Higgs boson production is observed in a dataset of 7 TeV pp collisions corresponding to 4.7 fb(-1) of integrated luminosity collected by ATLAS in 2011. Exclusion limits on Higgs boson production, at the 95% confidence level, of 2.5 to 5.5 times the Standard Model cross section are obtained in the mass range 110-130 GeV. The expected exclusion limits range between 2.5 and 4.9 for the same mass interval.
Address [Aad, G.; Ahles, F.; Barber, T.; Bernhard, R.; Bitenc, U.; Bruneliere, R.; Christov, A.; Fehling-Kaschek, M.; Flechl, M.; Glatzer, J.; Hartert, J.; Herten, G.; Horner, S.; Jakobs, K.; Janus, M.; Kollefrath, M.; Kononov, A. I.; Kuehn, S.; Lai, S.; Lohwasser, K.; Ludwig, I.; Ludwig, J.; Lumb, D.; Mahboubi, K.; Nilsen, H.; Rammensee, M.; Rave, T. C.; Schaarschmidt, J.; Schmidt, E.; Schumacher, M.; Siegert, F.; Stoerig, K.; Sundermann, J. E.; Temming, K. K.; Thoma, S.; Venturi, M.; Vivarelli, I.; von Radziewski, H.; Anh, T. Vu; Warsinsky, M.; Weiser, C.; Werner, M.; Wiik-Fuchs, L. A. M.; Winkelmann, S.; Xie, S.; Zimmermann, S.] Univ Freiburg, Fak Math & Phys, D-79106 Freiburg, Germany
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000312687700014 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1294
Permanent link to this record