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Author LHCb Collaboration (Aaij, R. et al); Garcia Martin, L.M.; Henry, L.; Jashal, B.K.; Martinez-Vidal, F.; Oyanguren, A.; Remon Alepuz, C.; Ruiz Vidal, J.; Sanchez Mayordomo, C.
Title Observation of the doubly Cabibbo-suppressed decay Xi(+)(c) -> p phi Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (up) 04 Issue 4 Pages 084 - 18pp
Keywords Flavor physics; Branching fraction; Charm physics; Hadron-Hadron scattering (experiments)
Abstract The doubly Cabibbo- suppressed decay Xi(+)(c) -> p phi with ! K+K is observed for the fi rst time, with a statistical signi fi cance of more than fi fteen standard deviations. The data sample used in this analysis corresponds to an integrated luminosity of 2 fb recorded with the LHCb detector in pp collisions at a centre- of- mass energy of 8TeV. The ratio of branching fractions between the decay + c ! p and the singly Cabibbo- suppressed decay + c ! pK is measured to be B (Xi(+)(c) -> p phi) B (Xi(+)(c) -> p phi) = (19 : 8 0 : 7 0 : 9 0 : 2) 10 where the fi rst uncertainty is statistical, the second systematic and the third due to the knowledge of the Xi(+)(c) -> pK(+)pi(+) branching fraction.
Address [Bediaga, I.; Cruz Torres, M.; De Miranda, J. M.; Gomes, A.; Massafferri, A.; dos Reis, A. C.; Soares Lavra, L.; Tourinho Jadallah Aoude, R.] CBPF, Rio De Janeiro, Brazil
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:000465438300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3993
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Author Oldengott, I.M.; Barenboim, G.; Kahlen, S.; Salvado, J.; Schwarz, D.J.
Title How to relax the cosmological neutrino mass bound Type Journal Article
Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume (up) 04 Issue 4 Pages 049 - 18pp
Keywords neutrino masses from cosmology; cosmological neutrinos; cosmological parameters from CMBR; cosmological parameters from LSS
Abstract We study the impact of non-standard momentum distributions of cosmic neutrinos on the anisotropy spectrum of the cosmic microwave background and the matter power spectrum of the large scale structure. We show that the neutrino distribution has almost no unique observable imprint, as it is almost entirely degenerate with the effective number of neutrino flavours, N-eff, and the neutrino mass, m(nu). Performing a Markov chain Monte Carlo analysis with current cosmological data, we demonstrate that the neutrino mass bound heavily depends on the assumed momentum distribution of relic neutrinos. The message of this work is simple and has to our knowledge not been pointed out clearly before: cosmology allows that neutrinos have larger masses if their average momentum is larger than that of a perfectly thermal distribution. Here we provide an example in which the mass limits are relaxed by a factor of two.
Address [Oldengott, Isabel M.; Barenboim, Gabriela] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: isabel.oldengott@uv.es;
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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000466578400003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4001
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Author NEXT Collaboration (Fernandes, A.F.M. et al); Alvarez, V.; Benlloch-Rodriguez, J.M.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Herrero, P.; Kekic, M.; Lopez-March, N.; Martinez-Lema, G.; Muñoz Vidal, J.; Novella, P.; Palmeiro, B.; Querol, M.; Renner, J.; Romo-Luque, C.; Sorel, M.; Uson, A.; Yahlali, N.
Title Low-diffusion Xe-He gas mixtures for rare-event detection: electroluminescence yield Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (up) 04 Issue 4 Pages 034 - 18pp
Keywords Particle correlations and fluctuations; Photon production; Dark Matter and Double Beta Decay (experiments); Rare decay
Abstract High pressure xenon Time Projection Chambers (TPC) based on secondary scintillation (electroluminescence) signal amplification are being proposed for rare event detection such as directional dark matter, double electron capture and double beta decay detection. The discrimination of the rare event through the topological signature of primary ionisation trails is a major asset for this type of TPC when compared to single liquid or double-phase TPCs, limited mainly by the high electron diffusion in pure xenon. Helium admixtures with xenon can be an attractive solution to reduce the electron diffu- sion significantly, improving the discrimination efficiency of these optical TPCs. We have measured the electroluminescence (EL) yield of Xe-He mixtures, in the range of 0 to 30% He and demonstrated the small impact on the EL yield of the addition of helium to pure xenon. For a typical reduced electric field of 2.5 kV/cm/bar in the EL region, the EL yield is lowered by similar to 2%, 3%, 6% and 10% for 10%, 15%, 20% and 30% of helium concentration, respectively. This decrease is less than what has been obtained from the most recent simulation framework in the literature. The impact of the addition of helium on EL statistical fluctuations is negligible, within the experimental uncertainties. The present results are an important benchmark for the simulation tools to be applied to future optical TPCs based on Xe-He mixtures.
Address [Hauptman, J.] Iowa State Univ, Dept Phys & Astron, 12 Phys Hall, Ames, IA 50011 USA, Email: cristinam@uc.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:000525257400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4366
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Author Folgado, M.G.; Donini, A.; Rius, N.
Title Gravity-mediated dark matter in clockwork/linear dilaton extra-dimensions Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (up) 04 Issue 4 Pages 036 - 46pp
Keywords Phenomenology of Field Theories in Higher Dimensions; Strings and branes phenomenology
Abstract We study for the first time the possibility that Dark Matter (represented by particles with spin 0, 1/2 or 1) interacts gravitationally with Standard Model particles in an extra-dimensional Clockwork/Linear Dilaton model. We assume that both, the Dark Matter and the Standard Model, are localized in the IR-brane and only interact via gravitational mediators, namely the Kaluza-Klein (KK) graviton and the radion/KK-dilaton modes. We analyse in detail the Dark Matter annihilation channel into Standard Model particles and into two on-shell Kaluza-Klein towers (either two KK-gravitons, or two radion/KK- dilatons, or one of each), finding that it is possible to obtain the observed relic abundance via thermal freeze-out for Dark Matter masses in the range m(DM) is an element of [1, 15] TeV for a 5- dimensional gravitational scale M-5 ranging from 5 to a few hundreds of TeV, even after taking into account the bounds from LHC Run II and irrespectively of the DM particle spin.
Address [Folgado, Miguel G.] Univ Valencia, Dept Fis Teor, CSIC, C Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: migarfol@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:000526531300002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4375
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Author Aguilar-Saavedra, J.A.; Casas, J.A.; Quilis, J.; Ruiz de Austri, R.
Title Multilepton dark matter signals Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume (up) 04 Issue 4 Pages 069 - 24pp
Keywords Beyond Standard Model; Gauge Symmetry
Abstract The signatures of dark matter at the LHC commonly involve, in simplified scenarios, the production of a single particle plus large missing energy, from the undetected dark matter. However, in Z ' -portal scenarios anomaly cancellation requires the presence of extra dark leptons in the dark sector. We investigate the signatures of the minimal scenarios of this kind, which involve cascade decays of the extra Z ' boson into the dark leptons, identifying a four-lepton signal as the most promising one. We estimate the sensitivity to this signal at the LHC, the high-luminosity LHC upgrade, a possible high-energy upgrade, as well as a future circular collider. For Z ' couplings compatible with current dijet constraints the multilepton signals can reach the 5 sigma level already at Run 2 of the LHC. At future colliders, couplings two orders of magnitude smaller than the electroweak coupling can be probed with 5 sigma sensitivity.
Address [Aguilar-Saavedra, J. A.; Casas, J. A.; Quilis, J.] Univ Autonoma Madrid, IFT, CSIC, E-28049 Madrid, Spain, Email: jaas@ugr.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:000528689700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4384
Permanent link to this record