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Author Bejarano, C.; Delhom, A.; Jimenez-Cano, A.; Olmo, G.J.; Rubiera-Garcia, D.
Title Geometric inequivalence of metric and Palatini formulations of General Relativity Type Journal Article
Year 2020 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 802 Issue Pages 135275 - 4pp
Keywords
Abstract Projective invariance is a symmetry of the Palatini version of General Relativity which is not present in the metric formulation. The fact that the Riemann tensor changes nontrivially under projective transformations implies that, unlike in the usual metric approach, in the Palatini formulation this tensor is subject to a gauge freedom, which allows some ambiguities even in its scalar contractions. In this sense, we show that for the Schwarzschild solution there exists a projective gauge in which the (affine) Kretschmann scalar, K (R beta μnu R alpha beta μnu)-R-alpha, can be set to vanish everywhere. This puts forward that the divergence of curvature scalars may, in some cases, be avoided by a gauge transformation of the connection.
Address [Bejarano, Cecilia] UBA, CONICET, IAFE, Casilla Correo 67,Sucursal 28, RA-1428 Buenos Aires, DF, Argentina, Email: cbejarano@iafe.uba.ar;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000515091400031 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4348
Permanent link to this record
 
 
Author Caputo, A.; Esposito, A.; Geoffray, E.; Polosa, A.D.; Sun, S.C.
Title Dark matter, dark photon and superfluid He-4 from effective field theory Type Journal Article
Year 2020 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 802 Issue Pages 135258 - 6pp
Keywords Light dark matter; Effective theory; Helium; Phonon; Dark photon
Abstract We consider a model of sub-GeV dark matter whose interaction with the Standard Model is mediated by a new vector boson (the dark photon) which couples kinetically to the photon. We describe the possibility of constraining such a model using a superfluid He-4 detector, by means of an effective theory for the description of the superfluid phonon. We find that such a detector could provide bounds that are competitive with other direct detection experiments only for ultralight vector mediator, in agreement with previous studies. As a byproduct we also present, for the first time, the low-energy effective field theory for the interaction between photons and phonons.
Address [Caputo, Andrea] Univ Valencia, Inst Fis Corpuscular, Edificio Inst Invest,Catedratico Jose Beltran 2, Paterna 46980, Spain, Email: angelo.esposito@epfl.ch
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000515091400017 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4349
Permanent link to this record
 
 
Author Escrihuela, F.J.; Flores, L.J.; Miranda, O.G.
Title Neutrino counting experiments and non-unitarity from LEP and future experiments Type Journal Article
Year 2020 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 802 Issue Pages 135241 - 8pp
Keywords
Abstract Non-unitarity of the neutrino mixing matrix is expected in many scenarios with physics beyond the Standard Model. Motivated by the search for deviations from unitary, we study two neutrino counting observables: the neutrino-antineutrino gamma process and the invisible Z boson decay into neutrinos. We report on new constraints for non-unitarity coming from the first of these observables. We study the potential constraints that future collider experiments will give from the invisible decay of the Z boson, that will be measured with improved precision.
Address [Escrihuela, F. J.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Parc Cient Paterna,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: franesfe@alumni.uv.es;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000515091400049 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4350
Permanent link to this record
 
 
Author Leite, J.; Popov, O.; Srivastava, R.; Valle, J.W.F.
Title A theory for scotogenic dark matter stabilised by residual gauge symmetry Type Journal Article
Year 2020 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 802 Issue Pages 135254 - 10pp
Keywords
Abstract Dark matter stability can result from a residual matter-parity symmetry, following naturally from the spontaneous breaking of the gauge symmetry. Here we explore this idea in the context of the SU(3)(c) circle times SU(3)L circle times U(1)(x) circle times U(1)(N) electroweak extension of the standard model. The key feature of our new scotogenic dark matter theory is the use of a triplet scalar boson with anti-symmetric Yukawa couplings. This naturally implies that one of the light neutrinos is massless and, as a result, there is a lower bound for the O nu beta beta decay rate.
Address [Leite, Julio; Srivastava, Rahul; Valle, Jose W. F.] Univ Valencia, CSIC, Inst Fis Corpuscular, AHEP Grp, Parc Cient Paterna,C Catedratico Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: julio.leite@ific.uv.es;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000515091400006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4351
Permanent link to this record
 
 
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 Measurement of f(s)/f(u) Variation with Proton-Proton Collision Energy and B-Meson Kinematics Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 124 Issue 12 Pages 122002 - 11pp
Keywords
Abstract The ratio of the B-s(0) and B+ fragmentation fractions f(s) and f(u) is studied with B-s(0) -> J/psi phi and B+ -> J/psi K+ decays using data collected by the LHCb experiment in proton-proton collisions at 7, 8, and 13 TeV center-of-mass energies. The analysis is performed in bins of B-meson momentum, longitudinal momentum, transverse momentum, pseudorapidity, and rapidity. The fragmentation-fraction ratio f(s)/f(u) is observed to depend on the B-meson transverse momentum with a significance of 6.0 sigma. This dependency is driven by the 13 TeV sample (8.7 sigma), while the results for the other collision energies are not significant when considered separately. Furthermore, the results show a 4.8 sigma evidence for an increase of f(s)/f(u) as a function of collision energy.
Address [Bediaga, I; Cruz Torres, M.; De Miranda, J. M.; dos Reis, A. C.; Gomes, A.; Massafferri, A.; Soares Lavra, L.] CBPF, Rio De Janeiro, Brazil
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000522195100005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4352
Permanent link to this record
 
 
Author Liang, W.H.; Oset, E.
Title Observed Omega(b) spectrum and meson-baryon molecular states Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 5 Pages 054033 - 6pp
Keywords
Abstract We observe that four peaks seen in the high energy part of the Omega(b) spectrum of the recent LHCb experiment are in remarkable agreement with predictions made for molecular Omega(b) states stemming from the meson-baryon interaction, with an approach that applied to the Omega(c) states gives rise to three states in good agreement with experiment in masses and widths. While the statistical significance of the peaks prevents us from claims of states at the present time, the agreement found should be an incentive to look at this experiment with increased statistics to give an answer to this suggestive idea.
Address [Liang, Wei-Hong; Oset, E.] Guangxi Normal Univ, Dept Phys, Guilin 541004, Peoples R China, Email: liangwh@gxnu.edu.cn;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000522162000006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4353
Permanent link to this record
 
 
Author ATLAS Collaboration (Aad, G. et al); Alvarez Piqueras, D.; 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.; 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 Evidence for electroweak production of two jets in association with a Z gamma pair in pp collisions at root S=13 TeV with the ATLAS detector Type Journal Article
Year 2020 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 803 Issue Pages 135341 - 23pp
Keywords
Abstract Evidence for electroweak production of two jets in association with a Z gamma pair in root s = 13 TeV proton-proton collisions at the Large Hadron Collider is presented. The analysis uses data collected by the ATLAS detector in 2015 and 2016 that corresponds to an integrated luminosity of 36.1 fb(-1). Events that contain a Z boson candidate decaying leptonically into either e(+)e(-) or mu(+)mu(-), a photon, and two jets are selected. The electroweak component is measured with observed and expected significances of 4.1 standard deviations. The fiducial cross-section for electroweak production is measured to be sigma(Z gamma jj-Ew) = 7.8 +/- 2.0 fb, in good agreement with the Standard Model prediction.
Address [Deliot, F.; Duvnjak, D.; Jackson, P.; Kong, A. X. Y.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000521730300023 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4354
Permanent link to this record
 
 
Author Liang, W.H.; Ikeno, N.; Oset, E.
Title Upsilon(nl) decay into B(*) (B)over-bar(*) Type Journal Article
Year 2020 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 803 Issue Pages 135340 - 6pp
Keywords
Abstract We have evaluated the decay modes of the Upsilon(4s), Upsilon(3d), Upsilon(5s), Upsilon(6s) states into B (B) over bar, B (B) over bar* + c.c., B* (B) over bar*, B-s(B) over bar (s), B-s(B) over bar (s)* + c.c., B-s* (B) over bar (s)* using the P-3(0) model to hadronize the bb vector seed, fitting some parameters to the data. We observe that the Upsilon(4s) state has an abnormally large amount of mesonmeson components in the wave function, while the other states are largely b (b) over bar. We predict branching ratios for the different decay channels which can be contrasted with experiment for the case of the Upsilon(5s) state. While globally the agreement is fair, we call the attention to some disagreement that could be a warning for the existence of more elaborate components in the state.
Address [Liang, Wei-Hong; Oset, Eulogio] Guangxi Normal Univ, Dept Phys, Guilin 541004, Peoples R China, Email: liangwh@gxnu.edu.cn;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000521730300046 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4355
Permanent link to this record
 
 
Author Molina, R.; Xie, J.J.; Liang, W.H.; Geng, L.S.; Oset, E.
Title Theoretical interpretation of the D-s(+) -> pi(+)pi(0)eta decay and the nature of a(0)(980) Type Journal Article
Year 2020 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 803 Issue Pages 135279 - 4pp
Keywords
Abstract In a recent paper [I], the BESIII Collaboration reported the so-called first observation of pure W-annihi- lation decays D-s(+) -> a(0)(+) (980)pi(0) and D-s(+) -> a(0)(0)(980)pi(+). The measured absolute branching fractions are, however, puzzlingly larger than those of other measured pure W-annihilation decays by at least one order of magnitude. In addition, the relative phase between the two decay modes is found to be about 0 degrees. In this letter, we show that all these can be easily understood if the a(0)(980) is a dynamically generated state from (K) over barK and pi eta interactions in coupled channels. In such a scenario, the D-s(+) decay proceeds via internal W emission instead of W-annihilation, which has a larger decay rate than W-annihilation. The proposed decay mechanism and the molecular nature of the a(0)(980) also provide a natural explanation to the measured negative interference between the two decay modes.
Address [Molina, Raquel; Liang, Wei-Hong; Oset, Eulogio] Guangxi Normal Univ, Dept Phys, Guilin 541004, Peoples R China, Email: raqumoli@ucm.es;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000521730300066 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4356
Permanent link to this record
 
 
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.; 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 Search for long-lived neutral particles produced in pp collisions at root s=13 TeV decaying into displaced hadronic jets in the ATLAS inner detector and muon spectrometer Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 5 Pages 052013 - 29pp
Keywords
Abstract A search is presented for pair production of long-lived neutral particles using 33 fb(-1) off root s = 13 TcV proton-proton collision data, collected during 2016 by the ATLAS detector at the LHC. This search focuses on a topology in which one long-lived particle decays in the ATLAS inner detector and the other decays in the muon spectrometer. Special techniques are employed to reconstruct the displaced tracks and vertices in the inner detector and in the muon spectrometer. One event is observed that passes the full event selection, which is consistent with the estimated background. Limits are placed on scalar boson propagators with masses from 125 GeV to 1000 GeV decaying into pairs of long-lived hidden-sector scalars with masses from 8 GeV to 400 GeV. The limits placed on several low-mass scalars extend previous exclusion limits in the range of proper lifetimes c tau from 5 cm to 1 m.
Address [Deliot, F.; Duvnjak, D.; Jackson, P.; Kong, A. X. Y.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000522163200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4357
Permanent link to this record