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Author Feijoo, A.; Molina, R.; Dai, L.R.; Oset, E.
Title Lambda(1405) mediated triangle singularity in the K(-)d -> p Sigma(-) reaction Type Journal Article
Year 2022 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 82 Issue 11 Pages 1028 - 16pp
Keywords
Abstract We study for the first time the p Sigma(-) -> K- d and K- d -> p Sigma(-) reactions close to threshold and show that they are driven by a triangle mechanism, with the Lambda(1405), a proton and a neutron as intermediate states, which develops a triangle singularity close to the (K) over bard threshold. We find that a mechanism involving virtual pion exchange and the K- p -> pi(+)Sigma(-) amplitude dominates over another one involving kaon exchange and the K- p -> K- p amplitude. Moreover, of the two Lambda(1405) states, the one with higher mass around 1420 MeV, gives the largest contribution to the process. We show that the cross section, well within measurable range, is very sensitive to different models that, while reproducing (K) over barN observables above threshold, provide different extrapolations of the (K) over barN amplitudes below threshold. The observables of this reaction will provide new constraints on the theoretical models, leading to more reliable extrapolations of the (K) over barN amplitudes below threshold and to more accurate predictions of the Lambda(1405) state of lower mass.
Address (down) [Feijoo, A.; Molina, R.; Oset, Eulogio] Univ Valencia, Dept Fis Teor, Inst Invest Paterna, CSIC,Ctr Mixto, Aptdo 22085, Valencia 46071, Spain, Email: edfeijoo@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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000884904400008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5417
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Author Feijoo, A.; Magas, V.K.; Ramos, A.; Oset, E.
Title A hidden-charm S =-1 pentaquark from the decay Lambda(b) into J/psi eta Lambda states Type Journal Article
Year 2016 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 76 Issue 8 Pages 446 - 12pp
Keywords
Abstract The hidden-charm pentaquark P-c(4450) observed recently by the LHCb collaboration may be of molecular nature, as advocated by some unitary approaches that also predict pentaquark partners in the strangeness S = -1 sector. In this work we argue that a hidden-charm strange pentaquark could be seen from the decay of the Lambda b, just as in the case of the non-strange P-c(4450), but looking into the J/psi eta Lambda decay mode and forming the invariant mass spectrum of J/psi Lambda pairs. In the model presented here, which assumes a standard weak decay topology and incorporates the hadronization process and final-state interaction effects, we find the J/psi eta Lambda final states to be populated with similar strength as the J/psi K- p states employed for the observation of the non-strange pentaquark. This makes the Lambda b -> J/psi eta Lambda decay to be an interesting process to observe a possible strange partner of the P-c(4450). We study the dependence of the J/psi Lambda mass spectra on various model ingredients and on the unknown properties of the strange pentaquark.
Address (down) [Feijoo, A.; Magas, V. K.; Ramos, A.] Univ Barcelona, Dept Fis Quant & Astrofis, Inst Ciencies Cosmos ICCUB, Marti & Franques 1, E-08028 Barcelona, Spain, Email: feijoo@icc.ub.edu;
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000399606600001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3058
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Author Esteban, I.; Lopez-Pavon, J.; Martinez-Soler, I.; Salvado, J.
Title Looking at the axionic dark sector with ANITA Type Journal Article
Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 80 Issue 3 Pages 259 - 9pp
Keywords
Abstract The ANITA experiment has recently observed two anomalous events emerging from well below the horizon. Even though they are consistent with tau cascades, a high-energy Standard Model or Beyond the Standard Model explanation is challenging and in tension with other experiments. We study under which conditions the reflection of generic radio pulses can reproduce these signals. Furthermore, we propose that these pulses can be resonantly produced in the ionosphere via axion-photon conversion. This naturally explains the direction and polarization of the events and avoids other experimental bounds.
Address (down) [Esteban, I; Salvado, J.] Univ Barcelona, Dept Fis Quant & Astrofis, Diagonal 647, E-08028 Barcelona, Spain, Email: ivan.esteban@fqa.ub.edu;
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000521957300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4345
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Author Escudero, M.; Witte, S.J.
Title A CMB search for the neutrino mass mechanism and its relation to the Hubble tension Type Journal Article
Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 80 Issue 4 Pages 294 - 10pp
Keywords
Abstract The majoron, a pseudo-Goldstone boson arising from the spontaneous breaking of global lepton number, is a generic feature of many models intended to explain the origin of the small neutrino masses. In this work, we investigate potential imprints in the cosmic microwave background (CMB) arising from massive majorons, should they thermalize with neutrinos after Big Bang Nucleosynthesis via inverse neutrino decays. We show that Planck2018 measurements of the CMB are currently sensitive to neutrino-majoron couplings as small as lambda similar to 10-13, which if interpreted in the context of the type-I seesaw mechanism correspond to a lepton number symmetry breaking scale vL similar to O(100)GeV Additionally, we identify parameter space for which the majoron-neutrino interactions, collectively with an extra contribution to the effective number of relativistic species Neff, can ameliorate the outstanding H0 tension.
Address (down) [Escudero, Miguel] Kings Coll London, Dept Phys, London WC2R 2LS, England, Email: miguel.escudero@kcl.ac.uk;
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000523450600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4361
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Author Escudero, M.; Rius, N.; Sanz, V.
Title Sterile neutrino portal to Dark Matter II: exact dark symmetry Type Journal Article
Year 2017 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 77 Issue 6 Pages 397 - 11pp
Keywords
Abstract We analyze a simple extension of the standard model (SM) with a dark sector composed of a scalar and a fermion, both singlets under the SM gauge group but charged under a dark sector symmetry group. Sterile neutrinos, which are singlets under both groups, mediate the interactions between the dark sector and the SM particles, and generate masses for the active neutrinos via the seesaw mechanism. We explore the parameter space region where the observed Dark Matter relic abundance is determined by the annihilation into sterile neutrinos, both for fermion and scalar Dark Matter particles. The scalar Dark Matter case provides an interesting alternative to the usual Higgs portal scenario. We also study the constraints from direct Dark Matter searches and the prospects for indirect detection via sterile neutrino decays to leptons, which may be able to rule out Dark Matter masses below and around 100 GeV.
Address (down) [Escudero, Miguel; Rius, Nuria] Univ Valencia, CSIC, Dept Fis Teor, C Catedrat Jose Beltran 2, Paterna 46980, Spain, Email: miguel.escudero@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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000403504200002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3171
Permanent link to this record