|   | 
Details
   web
Records
Author ATLAS Collaboration (Aad, G. et al); Alvarez Piqueras, D.; Aparisi Pozo, J.A.; Bailey, A.J.; Barranco Navarro, L.; 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; Higon-Rodriguez, E.; Jimenez Pena, J.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Melini, D.; Miñano, M.; Mitsou, V.A.; 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 Search for heavy neutral leptons in decays of W bosons produced in 13 TeV pp collisions using prompt and displaced signatures with the ATLAS detector Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages (down) 265 - 47pp
Keywords Hadron-Hadron scattering (experiments)
Abstract The problems of neutrino masses, matter-antimatter asymmetry, and dark matter could be successfully addressed by postulating right-handed neutrinos with Majorana masses below the electroweak scale. In this work, leptonic decays of W bosons extracted from 32.9 fb(-1) to 36.1 fb(-1) of 13 TeV proton-proton collisions at the LHC are used to search for heavy neutral leptons (HNLs) that are produced through mixing with muon or electron neutrinos. The search is conducted using the ATLAS detector in both prompt and displaced leptonic decay signatures. The prompt signature requires three leptons produced at the interaction point (either μμe or ee mu) with a veto on same-flavour opposite-charge topologies. The displaced signature comprises a prompt muon from the W boson decay and the requirement of a dilepton vertex (either μμor μe) displaced in the transverse plane by 4-300 mm from the interaction point. The search sets constraints on the HNL mixing to muon and electron neutrinos for HNL masses in the range 4.5-50 GeV.
Address [Deliot, F.; Duvnjak, D.; Jackson, P.; Meshkov, O.; Murray, W. J.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000520036900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4336
Permanent link to this record
 

 
Author Barreiros, D.M.; Joaquim, F.R.; Srivastava, R.; Valle, J.W.F.
Title Minimal scoto-seesaw mechanism with spontaneous CP violation Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 04 Issue 4 Pages (down) 249 - 21pp
Keywords Neutrino Physics; CP violation
Abstract We propose simple scoto-seesaw models to account for dark matter and neutrino masses with spontaneous CP violation. This is achieved with a single horizontal Z8 discrete symmetry, broken to a residual Z2 subgroup responsible for stabilizing dark matter. CP is broken spontaneously via the complex vacuum expectation value of a scalar singlet, inducing leptonic CP-violating effects. We find that the imposed Z8 symmetry pushes the values of the Dirac CP phase and the lightest neutrino mass to ranges already probed by ongoing experiments, so that normal-ordered neutrino masses can be cornered by cosmological observations and neutrinoless double beta decay experiments.
Address [Barreiros, D. M.; Joaquim, F. R.] Univ Lisbon, Dept Fis, Inst Super Tecn, Av Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: debora.barreiros@tecnico.ulisboa.pt;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000646917200003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4814
Permanent link to this record
 

 
Author Centelles Chulia, S.; Srivastava, R.; Vicente, A.
Title The inverse seesaw family: Dirac and Majorana Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages (down) 248 - 29pp
Keywords Beyond Standard Model; Neutrino Physics; Global Symmetries
Abstract After developing a general criterion for deciding which neutrino mass models belong to the category of inverse seesaw models, we apply it to obtain the Dirac analogue of the canonical Majorana inverse seesaw model. We then generalize the inverse seesaw model and obtain a class of inverse seesaw mechanisms both for Majorana and Dirac neutrinos. We further show that many of the models have double or multiple suppressions coming from tiny symmetry breaking “mu -parameters”. These models can be tested both in colliders and with the observation of lepton flavour violating processes.
Address [Centelles Chulia, Salvador; Vicente, Avelino] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Parc Cientif Paterna,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: salcen@ific.uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000635241800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4772
Permanent link to this record
 

 
Author Fontes, D.; Romao, J.C.; Valle, J.W.F.
Title Electroweak breaking and Higgs boson profile in the simplest linear seesaw model Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages (down) 245 - 28pp
Keywords Beyond Standard Model; Higgs Physics; Neutrino Physics
Abstract We examine the simplest realization of the linear seesaw mechanism within the Standard Model gauge structure. Besides the standard scalar doublet, there are two lepton-number-carrying scalars, a nearly inert SU(2)(L) doublet and a singlet. Neutrino masses result from the spontaneous violation of lepton number, implying the existence of a Nambu-Goldstone boson. Such “majoron” would be copiously produced in stars, leading to stringent astrophysical constraints. We study the profile of the Higgs bosons in this model, including their effective couplings to the vector bosons and their invisible decay branching ratios. A consistent electroweak symmetry breaking pattern emerges with a compressed spectrum of scalars in which the “Standard Model” Higgs boson can have a sizeable invisible decay into the invisible majorons.
Address [Fontes, Duarte; Romao, Jorge C.] Univ Lisbon, Inst Super Tecn, Dept Fis, Ave Rovisco Pais 1, P-1049001 Lisbon, Portugal, Email: duartefontes@tecnico.ulisboa.pt;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000495737300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4199
Permanent link to this record
 

 
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 Measurement of light-by-light scattering and search for axion-like particles with 2.2 nb(-1) of Pb+Pb data with the ATLAS detector Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages (down) 243 - 45pp
Keywords Hadron-Hadron scattering (experiments)
Abstract This paper describes a measurement of light-by-light scattering based on Pb+Pb collision data recorded by the ATLAS experiment during Run 2 of the LHC. The study uses 2.2 nb(-1) of integrated luminosity collected in 2015 and 2018 at root sNN = 5.02TeV. Light-by-light scattering candidates are selected in events with two photons produced exclusively, each with transverse energy E-T(gamma) > 2.5 GeV, pseudorapidity vertical bar eta(gamma)vertical bar < 2.37, diphoton invariant mass m(gamma gamma) > 5 GeV, and with small diphoton transverse momentum and diphoton acoplanarity. The integrated and differential fiducial cross sections are measured and compared with theoretical predictions. The diphoton invariant mass distribution is used to set limits on the production of axion-like particles. This result provides the most stringent limits to date on axion-like particle production for masses in the range 6-100 GeV. Cross sections above 2 to 70 nb are excluded at the 95% CL in that mass interval.
Address [Abud, A. Abed; Ahmad, A.; Alderweireldt, S.; Aleksa, M.; Allaire, C.; Aranzabal, N.; Armbruster, A. J.; Avolio, G.; Barisits, M-S; Bielski, R.; Bisanz, T.; Boyd, J.; Brenner, L.; Butti, P.; Buttinger, W.; Calace, N.; Camarda, S.; Camincher, C.; Campana, S.; Garrido, M. D. M. Capeans; Carli, T.; Catinaccio, A.; Cattai, A.; Coimbra, A. E. C.; Czodrowski, P.; Dachs, F.; Dao, V; Dell'Acqua, A.; Deviveiros, P. O.; Di Girolamo, A.; Dittus, F.; Ducu, O. A.; Dudarev, A.; Duhrssen, M.; Dyndal, M.; Ellis, N.; Elsing, M.; Falke, S.; Farthouat, P.; Fassnacht, P.; Francis, D.; Froidevaux, D.; Gabrielli, A.; Goossens, L.; Gorini, B.; Guindon, S.; Hawkings, R. J.; Heinrich, L.; Helsens, C.; Correia, A. M. Henriques; Hervas, L.; Hoecker, A.; Huhtinen, M.; Iengo, P.; Jenni, P.; Jovicevic, J.; Kiehn, M.; Klimek, P.; Klioutchnikova, T.; Kohler, N. M.; Krasznahorkay, A.; Kuehn, S.; Kuwertz, E. S.; Lassnig, M.; Miotto, G. Lehmann; Longo, L.; Marzin, A.; Meehan, S.; Meng, L.; Berlingen, J. Montejo; Morley, A. K.; Mornacchi, G.; Moschovakos, P.; Nairz, A. M.; Nessi, M.; Nordberg, M.; Palestini, S.; Pauly, T.; Pernegger, H.; Perrella, S.; Petersen, B. A.; Pontecorvo, L.; Astigarraga, M. E. Pozo; Queitsch-Maitland, M.; Raymond, M.; Rembser, C.; Rizzi, C.; Roe, S.; Rummler, A.; Saimpert, M.; Salzburger, A.; Samarati, J.; Pineda, A. Sanchez; Schlenker, S.; Schovancova, J.; Sharma, A.; Sidiropoulou, O.; Oliveira, M. V. Silva; Sanchez, C. A. Solans; Spigo, G.; Stewart, G. A.; Stockton, M. C.; Ten Kate, H.; Unal, G.; Vafeiadis, T.; Vallier, A.; Vandelli, W.; Schroeder, T. Vazquez; Vuillermet, R.; Wells, P. S.; Wengler, T.; Wenig, S.; Wilkens, H. G.; Young, C. J. S.; Zambito, S.; Zanzi, D.; Zwalinski, L.; ATLAS Collaboration] CERN, CH-1211 Geneva 23, Switzerland
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000634886800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4768
Permanent link to this record