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Author Alekhin, S. et al; Hernandez, P.
Title (up) A facility to search for hidden particles at the CERN SPS: the SHiP physics case Type Journal Article
Year 2016 Publication Reports on Progress in Physics Abbreviated Journal Rep. Prog. Phys.
Volume 79 Issue 12 Pages 124201 - 137pp
Keywords beyond the standard model physics; intensity frontier experiment; hidden sectors; heavy neutral leptons; dark photons
Abstract This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (search for hidden particles) experiment is intended to hunt for new physics in the largely unexplored domain of very weakly interacting particles with masses below the Fermi scale, inaccessible to the LHC experiments, and to study tau neutrino physics. The same proton beam setup can be used later to look for decays of tau-leptons with lepton flavour number non-conservation, tau -> 3 μand to search for weakly-interacting sub-GeV dark matter candidates. We discuss the evidence for physics beyond the standard model and describe interactions between new particles and four different portals-scalars, vectors, fermions or axion-like particles. We discuss motivations for different models, manifesting themselves via these interactions, and how they can be probed with the SHiP experiment and present several case studies. The prospects to search for relatively light SUSY and composite particles at SHiP are also discussed. We demonstrate that the SHiP experiment has a unique potential to discover new physics and can directly probe a number of solutions of beyond the standard model puzzles, such as neutrino masses, baryon asymmetry of the Universe, dark matter, and inflation.
Address [Alekhin, Sergey] DESY, Platanenallee 6, D-15738 Zeuthen, Germany, Email: oleg.ruchayskiy@cern.ch
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 0034-4885 ISBN Medium
Area Expedition Conference
Notes WOS:000387025400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2852
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Author ATLAS Collaboration (Aad, G. et al); Alvarez Piqueras, D.; Barranco Navarro, L.; Cabrera Urban, S.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Fernandez Martinez, P.; Ferrer, A.; Fiorini, L.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Hernandez Jimenez, Y.; Higon-Rodriguez, E.; Irles Quiles, A.; Jimenez Pena, J.; Kaci, M.; King, M.; Lacasta, C.; Lacuesta, V.R.; Marti-Garcia, S.; Mitsou, V.A.; Pedraza Lopez, S.; Romero Adam, E.; Ros, E.; Salt, J.; Sanchez Martinez, V.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M.
Title (up) A search for an excited muon decaying to a muon and two jets in pp collisions at root s=8 TeV with the ATLAS detector Type Journal Article
Year 2016 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 18 Issue Pages 073021 - 21pp
Keywords excited leptons; lepton compositeness; leptoquarks
Abstract Anew search signature for excited leptons is explored. Excited muons are sought in the channel pp -> μmu* -> μμjet jet, assuming both the production and decay occur via a contact interaction. The analysis is based on 20.3 fb(-1) of pp collision data at a centre-of-mass energy of root s = 8 TeV taken with the ATLAS detector at the large hadron collider. No evidence of excited muons is found, and limits are set at the 95% confidence level on the cross section times branching ratio as a function of the excited-muon mass m(mu)*. For m(mu)* between 1.3 and 3.0 TeV, the upper limit on sigma B(mu* -> μq (q) over bar) is between 0.6 and 1 fb. Limits on sB are converted to lower bounds on the compositeness scale Lambda. In the limiting case Lambda = m(mu)*, excited muons with a mass below 2.8 TeV are excluded. With the same model assumptions, these limits at larger mu* masses improve upon previous limits from traditional searches based on the gauge-mediated decay mu* -> μgamma.
Address [Jackson, P.; Lee, L.; Petridis, A.; Soni, N.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
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 1367-2630 ISBN Medium
Area Expedition Conference
Notes WOS:000381870700003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2800
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Author Correia, F.C.
Title (up) Fundamentals of the 3-3-1 model with heavy leptons Type Journal Article
Year 2018 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 45 Issue 4 Pages 043001 - 31pp
Keywords 3-3-1 models; heavy leptons; heavy quarks
Abstract This work is a brief presentation of the theory based on the SU(3)(c) circle times SU(3)(L) circle times U(1)(X) gauge group in the presence of heavy leptons. Recent studies [1] have considered a set of four possible variants for the 3-3-1HL, whose content arises according to the so-denoted variable beta. Since it has been argued about the presence of stable charged particles in this sort of model, we divide the different sectors of the Lagrangian between universal and specific vertices, and conclude that the omission of beta-dependent terms in the potential may induce discrete symmetry for the versions defined by vertical bar beta vertical bar = root 3 . In the context of vertical bar beta vertical bar = 1/root 3, where the new degrees of freedom have the same standard electric charges, additional Yukawa interactions may create decay channels into the SM sector. Furthermore, motivated by a general consequence of the Goldstone theorem, a method of diagonalization by parts is introduced in the Scalar sector and provides a clarification on the definition of mass eigenstates. In summary, we develop the most complete set of terms allowed by the symmetry group and resolve their definitive pieces in order to justify the model description present in the literature.
Address [Correia, F. C.] Sao Paulo State Univ, UNESP, Inst Theoret Phys, BR-01140070 Sao Paulo, SP, Brazil, Email: ccorreia@ift.unesp.br
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 0954-3899 ISBN Medium
Area Expedition Conference
Notes WOS:000425634400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3504
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Author HADES Collaboration (Agakishiev, G. et al); Diaz, J.; Gil, A.
Title (up) Origin of the low-mass electron pair excess in light nucleus-nucleus collisions Type Journal Article
Year 2010 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 690 Issue 2 Pages 118-122
Keywords Virtual bremsstrahlung; Dileptons; Nucleon-nucleon collisions
Abstract We report measurements of electron pair production in elementary p + p and d + p reactions at 1.25 GeV/mu with the HADES spectrometer. For the first time, the electron pairs were reconstructed for n + p reactions by detecting the proton spectator from the deuteron breakup. We find that the yield of electron pairs with invariant mass Me+e- > 0.15 GeV/c(2) is about an order of magnitude larger in n + p reactions as compared to p + p. A comparison to model calculations demonstrates that the production mechanism is not sufficiently described yet. The electron pair spectra measured in C + C reactions are compatible with a superposition of elementary n + p and p + p collisions, leaving little room for additional electron pair sources in such light collision systems.
Address [Froehlich, I.; Galatyuk, T.; Goebel, K.; Lorenz, M.; Markert, J.; Michel, J.; Muentz, C.; Pachmayer, Y. C.; Stroebele, H.; Stroth, J.; Sturm, C.; Tarantola, A.; Teilab, K.] Goethe Univ Frankfurt, Inst Kernphys, D-60438 Frankfurt, Germany, Email: t.galatyuk@gsi.de
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes ISI:000279513800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 413
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Author Pich, A.
Title (up) Precision tau physics Type Journal Article
Year 2014 Publication Progress in Particle and Nuclear Physics Abbreviated Journal Prog. Part. Nucl. Phys.
Volume 75 Issue Pages 41-85
Keywords Electroweak and strong interactions; Leptons; Standard Model
Abstract Precise measurements of the lepton properties provide stringent tests of the Standard Model and accurate determinations of its parameters. We overview the present status of tau physics, highlighting the most recent developments, and discuss the prospects for future improvements. The leptonic decays of the tau lepton probe the structure of the weak currents and the universality of their couplings to the W boson. The universality of the leptonic Z couplings has also been tested through Z -> l(+)l(-) decays. The hadronic tau decay modes constitute an ideal tool for studying low-energy effects of the strong interaction in very clean conditions. Accurate determinations of the QCD coupling and the Cabibbo mixing V-us have been obtained with tau data. The large mass of the tau opens the possibility to study many kinematically-allowed exclusive decay modes and extract relevant dynamical information. Violations of flavour and CP conservation laws can also be searched for with tau decays. Related subjects such as μdecays, the electron and muon anomalous magnetic moments, neutrino mixing and B-meson decays into tau leptons are briefly covered. Being one the fermions most strongly coupled to the scalar sector, the tau lepton is playing now a very important role at the LHC as a tool to test the Higgs properties and search for new physics at higher scales.
Address Univ Valencia, CSIC, Dept Fis Teor, IFIC, E-46071 Valencia, Spain, Email: pich@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0146-6410 ISBN Medium
Area Expedition Conference
Notes WOS:000332350600002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 1716
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