|   | 
Details
   web
Records
Author Ghosh, P.; Lara, I.; Lopez-Fogliani, D.E.; Muñoz, C.; Ruiz de Austri, R.
Title Searching for left sneutrino LSP at the LHC Type Journal Article
Year (down) 2018 Publication International Journal of Modern Physics A Abbreviated Journal Int. J. Mod. Phys. A
Volume 33 Issue 18-19 Pages 1850110 - 62pp
Keywords Supersymmetry phenomenology; supersymmetric Standard Model
Abstract We analyze relevant signals expected at the LHC for a left sneutrino as the lightest supersymmetric particle (LSP). The discussion is carried out in the “mu from nu” supersymmetric standard model (mu nu SSM), where the presence of R-parity breaking couplings involving right-handed neutrinos solves the μproblem and reproduces neutrino data. The sneutrinos are pair produced via a virtual W, Z or gamma in the s channel. From the prompt decay of a pair of left sneutrinos LSPs of any family, a significant diphoton signal plus missing transverse energy (MET) from neutrinos can be present in the mass range 118-132 GeV, with 13 TeV center-of-mass energy and an integrated luminosity of 100 fb(-1). In addition, in the case of a pair of tau left sneutrinos LSPs, given the large value of the tau Yukawa coupling diphoton plus leptons and/or multileptons can appear. We find that the number of expected events for the multilepton signal, together with properly adopted search strategies, is sufficient to give a significant evidence for a sneutrino of mass in the range 130-310 GeV, even with the integrated luminosity of 20 fb(-1). In the case of the signal producing diphoton plus leptons, an integrated luminosity of 100 fb(-1) is needed to give a significant evidence in the mass range 95-145 GeV. Finally, we discuss briefly the presence of displaced vertices and the associated range of masses.
Address [Ghosh, Pradipta] Vidyasagar Coll, Dept Phys, 39 Sankar Ghose Lane, Kolkata 700006, India, Email: tphyspg@gmail.com;
Corporate Author Thesis
Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-751x ISBN Medium
Area Expedition Conference
Notes WOS:000438183700004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3654
Permanent link to this record
 

 
Author Lara, I.; Lopez-Fogliani, D.E.; Muñoz, C.; Nagata, N.; Otono, H.; Ruiz de Austri, R.
Title Looking for the left sneutrino LSP with displaced-vertex searches Type Journal Article
Year (down) 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 7 Pages 075004 - 17pp
Keywords
Abstract We analyze a displaced dilepton signal expected at the LHC for a tau left sneutrino as the lightest supersymmetric particle with a mass in the range 45-100 GeV. The sneutrinos are pair produced via a virtual W, Z or gamma in the s channel and, given the large value of the tau Yukawa coupling, their decays into two dileptons or a dilepton plus missing transverse energy from neutrinos can be significant. The discussion is carried out in the framework of the μnu SSM, where the presence of R-parity violating couplings involving right-handed neutrinos solves the μproblem and can reproduce the neutrino data. To probe the tau left sneutrinos we compare the predictions of this scenario with the ATLAS search for long-lived particles using displaced lepton pairs in pp collisions at root s = 8 TeV, allowing us to constrain the parameter space of the model. We also consider an optimization of the trigger requirements used in existing displaced-vertex searches by means of a high level trigger that exploits tracker information. This optimization is generically useful for a light metastable particle decaying into soft charged leptons. The constraints on the sneutrino turn out to be more stringent. We finally discuss the prospects for the 13 TeV LHC searches as well as further potential optimizations.
Address [Lara, Inaki; Munoz, Carlos] Univ Autonoma Madrid, Dept Fis Teor, Campus Cantoblanco, E-28049 Madrid, Spain, Email: inaki.lara@csic.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000446298100007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3748
Permanent link to this record
 

 
Author Gomez-Vargas, G.A.; Lopez-Fogliani, D.E.; Muñoz, C.; Perez, A.D.; Ruiz de Austri, R.
Title Search for sharp and smooth spectral signatures of μnu SSM gravitino dark matter with Fermi- LAT Type Journal Article
Year (down) 2017 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 03 Issue 3 Pages 047 - 23pp
Keywords dark matter experiments; dark matter theory; gamma ray experiments
Abstract The μnu SSM solves the μproblem of supersymmetric models and reproduces neutrino data, simply using couplings with right-handed neutrinos nu's. Given that these couplings break explicitly R parity, the gravitino is a natural candidate for decaying dark matter in the μnu SSM. In this work we carry out a complete analysis of the detection of μnu SSM gravitino dark matter through gamma-ray observations. In addition to the two-body decay producing a sharp line, we include in the analysis the three-body decays producing a smooth spectral signature. We perform first a deep exploration of the low-energy parameter space of the μnu SSM taking into account that neutrino data must be reproduced. Then, we compare the gamma-ray fluxes predicted by the model with Fermi-LAT observations. In particular, with the 95% CL upper limits on the total diffuse extragalactic gamma-ray background using 50 months of data, together with the upper limits on line emission from an updated analysis using 69.9 months of data. For standard values of bino and wino masses, gravitinos with masses larger than about 4 GeV, or lifetimes smaller than about 10(28) s, produce too large fluxes and are excluded as dark matter candidates. However, when limiting scenarios with large and close values of the gaugino masses are considered, the constraints turn out to be less stringent, excluding masses larger than 17 GeV and lifetimes smaller than 4 x 10(25) s.
Address [Gomez-Vargas, German A.; Lopez-Fogliani, Daniel E.; Munoz, Carlos; Perez, Andres D.; Ruiz de Austri, Roberto] Pontificia Univ Catolica Chile, AInstituto Astrofis, Ave Vicu Mackenna 4860, Santiago, Chile, Email: ggomezv@uc.cl;
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:000405653700036 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3210
Permanent link to this record
 

 
Author Ghosh, P.; Lopez-Fogliani, D.E.; Mitsou, V.A.; Muñoz, C.; Ruiz de Austri, R.
Title Hunting physics beyond the standard model with unusual W-+/- and Z decays Type Journal Article
Year (down) 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 91 Issue 3 Pages 035020 - 8pp
Keywords
Abstract Nonstandard on-shell decays of W-+/- and Z bosons are possible within the framework of extended supersymmetric models, i.e., with singlet states and/or new couplings compared to the minimal supersymmetric standard model. These modes are typically encountered in regions of the parameter space with light singlet-like scalars, pseudoscalars, and neutralinos. In this letter we emphasize how these states can lead to novel signals at colliders from Z- or W-+/--boson decays with prompt or displaced multileptons/tau jets/jets/photons in the final states. These new modes would give distinct evidence of new physics even when direct searches remain unsuccessful. We discuss the possibilities of probing these new signals using the existing LHC run-I data set. We also address the same in the context of the LHC run-II, as well as for the future colliders. We exemplify our observations with the “mu from v” supersymmetric standard model, where three generations of right-handed neutrino superfields are used to solve shortcomings of the minimal supersymmetric standard model. We also extend our discussion for other variants of supersymmetric models that can accommodate similar signatures.
Address [Ghosh, Pradipta; Munoz, Carlos] Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain, Email: pradipta.ghosh@uam.es;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000352305400009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2185
Permanent link to this record
 

 
Author Ghosh, P.; Lopez-Fogliani, D.E.; Mitsou, V.A.; Muñoz, C.; Ruiz de Austri, R.
Title Probing the μnu SSM with light scalars, pseudoscalars and neutralinos from the decay of a SM-like Higgs boson at the LHC Type Journal Article
Year (down) 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 102 - 57pp
Keywords Supersymmetry Phenomenology
Abstract The “mu from nu” supersymmetric standard model (mu nu SSM) can accommodate the newly discovered Higgs-like scalar boson with a mass around 125GeV. This model provides a solution to the mu-problem and simultaneously reproduces correct neutrino physics by the simple use of right-handed neutrino superfields. These new superfields together with the introduced R-parity violation can produce novel and characteristic signatures of the μnu SSM at the LHC. We explore the signatures produced through two-body Higgs decays into the new states, provided that these states lie below in the mass spectrum. For example, a pair produced light neutralinos depending on the associated decay length can give rise to displaced multi-leptons/taus/jets/photons with small/moderate missing transverse energy. In the same spirit, a Higgs-like scalar decaying to a pair of scalars/pseudoscalars can produce final states with prompt multi-leptons/taus/jets/photons.
Address [Ghosh, Pradipta; Munoz, Carlos] Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain, Email: pradipta.ghosh@uam.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:000345590600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2016
Permanent link to this record