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Author (up) Chang, Q.; Li, X.Q.; Yang, Y.D.
Title The effects of a family nonuniversal Z ' boson on B -> pi pi decays Type Journal Article
Year 2011 Publication International Journal of Modern Physics A Abbreviated Journal Int. J. Mod. Phys. A
Volume 26 Issue 7-8 Pages 1273-1294
Keywords B-physics; rare decays; beyond Standard Model
Abstract Motivated by the measured large branching ratio of (B) over bar (0) --> pi(0)pi(0) (the so-called pi pi puzzle), we investigate the effects of a family nonuniversal Z' model on the tree-dominated B --> pi pi decays. We find that the Z' coupling parameter zeta(LR)(d) similar to 0.05 with a nontrivial new weak phase phi(L)(d) similar to -50 degrees, which is relevant to the Z' contributions to the QCD penguin sector Delta C-5, is needed to reconcile the observed discrepancy. Combined with the recent fitting results from B --> pi K, pi K* and rho K decays, the Z' parameter spaces are severely reduced but still not excluded entirely, implying that both the “pi pi” and “pi K” puzzles could be accommodated simultaneously within such a family nonuniversal Z' model.
Address [Chang, Qin; Li, Xin-Qiang] Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China, Email: changqin@htu.cn
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 ISI:000289175800004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 595
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Author (up) Cheng, L.; Eberhardt, O.; Murphy, C.W.
Title Novel theoretical constraints for color-octet scalar models Type Journal Article
Year 2019 Publication Chinese Physics C Abbreviated Journal Chin. Phys. C
Volume 43 Issue 9 Pages 093101 - 11pp
Keywords beyond the Standard Model; extension of Higgs sector; EW symmetry breaking
Abstract We study the theoretical constraints on a model whose scalar sector contains one color octet and one or two color singlet SU(2)(L) doublets. To ensure unitarity of the theory, we constrain the parameters of the scalar potential for the first time at the next-to-leading order in perturbation theory. Moreover, we derive new conditions guaranteeing the stability of the potential. We employ the HEPfit package to extract viable parameter regions at the electroweak scale and test the stability of the renormalization group evolution up to the multi-TeV region. Furthermore, we set upper limits on the scalar mass splittings. All results are given for both cases with and without a second scalar color singlet.
Address [Cheng, Li] Inst Appl Phys & Computat Math, Beijing 100094, Peoples R China, Email: clmamuphy@sina.cn;
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 1674-1137 ISBN Medium
Area Expedition Conference
Notes WOS:000482015900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4115
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Author (up) Chowdhury, D.; Eberhardt, O.
Title Update of global Two-Higgs-Doublet model fits Type Journal Article
Year 2018 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 161 - 42pp
Keywords Beyond Standard Model; Higgs Physics
Abstract We perform global fits of Two-Higgs-Doublet models with a softly broken Z(2) symmetry to recent results from the LHC detectors CMS and ATLAS, that is signal strengths and direct search limits obtained at root s = 8 TeV and root s = 13 TeV. We combine all available ATLAS and CMS constraints with the other relevant theoretical and experimental bounds and present the latest limits on the model parameters. We obtain that deviations from the so-called alignment limit beta-alpha = pi/2 cannot be larger than 0.03 in type I and have to be smaller than 0.02 in the remaining three types. For the latter, we also observe lower limits on the heavy Higgs masses in the global fit. The splittings between these masses cannot exceed 200 GeV in the types I and X and 130 GeV in the types II and Y. Finally, we find that the decay widths of the heavy Higgs particles cannot be larger than 7% of their masses if they are lighter than 1.5 TeV.
Address [Chowdhury, Debtosh] Ist Nazl Fis Nucl, Sez Roma, Piazzale Aldo Moro 2, I-00185 Rome, Italy, Email: Debtosh.Chowdhury@polytechnique.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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000433263300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3595
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Author (up) Cirigliano, V.; Jenkins, J.P.; Gonzalez-Alonso, M.
Title Semileptonic decays of light quarks beyond the Standard Model Type Journal Article
Year 2010 Publication Nuclear Physics B Abbreviated Journal Nucl. Phys. B
Volume 830 Issue 1-2 Pages 95-115
Keywords Semileptonic decays; CKM unitarity; Effective theory; Beyond the Standard Model
Abstract We describe non-standard contributions to semileptonic processes in a model independent way in terms of in SU(2)(L) x U(1)(Y) invariant effective lagrangian at the weak scale, front which we derive the low-energy effective lagrangian governing muon and beta decays. We find that the deviation from Cabibbo universality, Delta(CKM) equivalent to vertical bar V-ud vertical bar(2) + vertical bar V-us vertical bar(2) + vertical bar V-ub vertical bar(2) – 1, receives contributions from four effective operators. The phenomenological bound Delta(CKM) = (-1 +/- 6) x 10(-4) provides strong constraints on all four operators, corresponding to art effective scale Lambda > 11 TeV (90% CL). Depending on the operator, this constraint is at the same level or better then the Z pole observables. Conversely, precision electroweak constraints alone would allow universality violations as large as Delta(CKM) = -0.01 (90% CL). An observed Delta(CKM) not equal 0 at this level Could be explained in terms of a single four-fermion operator which is relatively poorly constrained by electroweak precision measurements.
Address [Cirigliano, Vincenzo; Jenkins, James P.; Gonzalez-Alonso, Martin] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA, Email: cirigliano@lanl.gov
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 0550-3213 ISBN Medium
Area Expedition Conference
Notes ISI:000275150000003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 497
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Author (up) Coito, L.; Faubel, C.; Herrero-Garcia, J.; Santamaria, A.
Title Dark matter from a complex scalar singlet: the role of dark CP and other discrete symmetries Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 202 - 34pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM
Abstract We study the case of a pseudo-scalar dark matter candidate which emerges from a complex scalar singlet, charged under a global U(1) symmetry, which is broken both explicitly and spontaneously. The pseudo-scalar is naturally stabilized by the presence of a remnant discrete symmetry: dark CP. We study and compare the phenomenology of several simplified models with only one explicit symmetry breaking term. We find that several regions of the parameter space are able to reproduce the observed dark matter abundance while respecting direct detection and invisible Higgs decay limits: in the resonances of the two scalars, featuring the known as forbidden or secluded dark matter, and through non-resonant Higgs-mediated annihilations. In some cases, combining different measurements would allow one to distinguish the breaking pattern of the symmetry. Moreover, this setup admits a light DM candidate at the sub-GeV scale. We also discuss the situation where more than one symmetry breaking term is present. In that case, the dark CP symmetry may be spontaneously broken, thus spoiling the stability of the dark matter candidate. Requiring that this does not happen imposes a constraint on the allowed parameter space. Finally, we consider an effective field theory approach valid in the pseudo-Nambu-Goldstone boson limit and when the U(1) breaking scale is much larger than the electroweak scale.
Address [Coito, Leonardo] Univ Valencia, Dept Fis Teor, Dr Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: leonardo.coito@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:000723081600002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5031
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Author (up) Coloma, P.; Donini, A.; Fernandez-Martinez, E.; Hernandez, P.
Title Precision on leptonic mixing parameters at future neutrino oscillation experiments Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 073 - 27pp
Keywords Neutrino Physics; CP violation; Standard Model
Abstract We perform a comparison of the different future neutrino oscillation experiments based on the achievable precision in the determination of the fundamental parameters theta(13) and the CP phase, delta, assuming that theta(13) is in the range indicated by the recent Daya Bay measurement. We study the non-trivial dependence of the error on delta on its true value. When matter effects are small, the largest error is found at the points where CP violation is maximal, and the smallest at the CP conserving points. The situation is different when matter effects are sizable. As a result of this effect, the comparison of the physics reach of different experiments on the basis of the CP discovery potential, as usually done, can be misleading. We have compared various proposed super-beam, beta-beam and neutrino factory setups on the basis of the relative precision of theta(13) and the error on delta. Neutrino factories, both high-energy or low-energy, outperform alternative beam technologies. An ultimate precision on theta(13) below 3% and an error on delta of <= 7 degrees at 1 sigma (1 d.o.f.) can be obtained at a neutrino factory.
Address [Coloma, P.] Virginia Tech, Dept Phys, Ctr Neutrino Phys, Blacksburg, VA 24061 USA, Email: coloma@vt.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 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000306416500074 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1141
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Author (up) Coloma, P.; Donini, A.; Lopez-Pavon, J.; Minakata, H.
Title Non-standard interactions at a neutrino factory: correlations and CP violation Type Journal Article
Year 2011 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 036 - 41pp
Keywords Beyond Standard Model; Neutrino Physics
Abstract We explore the potential of several Neutrino Factory (NF) setups to constrain, discover and measure new physics effects due to Non-Standard Interactions (NSI) in propagation through Earth matter. We first study the impact of NSI in the measurement of theta(13): we find that these could be large due to strong correlations of theta(13) with NSI parameters in the golden channel, and the inclusion of a detector at the magic baseline is crucial in order to reduce them as much as possible. We present, then, the sensitivity of the considered NF setups to the NSI parameters, paying special attention to correlations arising between them and the standard oscillation parameters, when all NSI parameters are introduced at once. Off-diagonal NSI parameters could be tested down to the level of 10(-3), whereas the diagonal combinations (epsilon(ee) – epsilon(tau tau)) and (epsilon(mu mu) – epsilon(tau tau)) can be tested down to 10(-1) and 10(-2), respectively. The possibilities of observing CP violation in this context are also explored, by presenting a first scan of the CP discovery potential of the NF setups to the phases phi(e mu), phi(e tau) and delta. We study separately the case where CP violation comes only from non-standard sources, and the case where it is entangled with the standard source, delta. In case delta turns out to be CP conserving, the interesting possibility of observing CP violation for reasonably small values of the NSI parameters emerges.
Address [Coloma, P] Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain, Email: p.coloma@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 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000294901400046 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 772
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Author (up) Coloma, P.; Esteban, I.; Gonzalez-Garcia, M.C.; Maltoni, M.
Title Improved global fit to Non-Standard neutrino Interactions using COHERENT energy and timing data Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 023 - 30pp
Keywords Beyond Standard Model; Neutrino Physics; Solar and Atmospheric Neutrinos
Abstract We perform a global fit to neutrino oscillation and coherent neutrino-nucleus scattering data, using both timing and energy information from the COHERENT experiment. The results are used to set model-independent bounds on four-fermion effective operators inducing non-standard neutral-current neutrino interactions. We quantify the allowed ranges for their Wilson coefficients, as well as the status of the LMA-D solution, for a wide class of new physics models with arbitrary ratios between the strength of the operators involving up and down quarks. Our results are presented for the COHERENT experiment alone, as well as in combination with the global data from oscillation experiments. We also quantify the dependence of our results for COHERENT with respect to the choice of quenching factor, nuclear form factor, and the treatment of the backgrounds.
Address [Coloma, Pilar] Univ Valencia, Inst Fis Corpuscular, Edificio Inst Invest, E-46980 Valencia, Spain, Email: pcoloma@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:000519223000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4330
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Author (up) Coloma, P.; Lopez-Pavon, J.; Rosauro-Alcaraz, S.; Urrea, S.
Title New physics from oscillations at the DUNE near detector, and the role of systematic uncertainties Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 065 - 33pp
Keywords Beyond Standard Model; Neutrino Physics
Abstract We study the capabilities of the DUNE near detector to probe deviations from unitarity of the leptonic mixing matrix, the 3+1 sterile formalism and Non-Standard Interactions affecting neutrino production and detection. We clarify the relation and possible mappings among the three formalisms at short-baseline experiments, and we add to current analyses in the literature the study of the nu(mu)-> nu(tau) appearance channel. We study in detail the impact of spectral uncertainties on the sensitivity to new physics using the DUNE near detector, which has been widely overlooked in the literature. Our analysis shows that this plays an important role on the results and, in particular, that it can lead to a strong reduction in the sensitivity to sterile neutrinos from nu(mu)-> nu(e) transitions, by more than two orders of magnitude. This stresses the importance of a joint experimental and theoretical effort to improve our understanding of neutrino nucleus cross sections, as well as hadron production uncertainties and beam focusing effects. Nevertheless, even with our conservative and more realistic implementation of systematic uncertainties, we find that an improvement over current bounds in the new physics frameworks considered is generally expected if spectral uncertainties are below the 5% level.
Address [Coloma, Pilar; Rosauro-Alcaraz, Salvador] Univ Autonoma Madrid, Inst Fis Teor, UAM CSIC, Calle Nicolas Cabrera 13-15, E-28049 Madrid, Spain, Email: pilar.coloma@ift.csic.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:000686712300001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4944
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Author (up) Cosme, C.; Dutra, M.; Godfrey, S.; Gray, T.
Title Testing freeze-in with axial and vector Z ' bosons Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 09 Issue 9 Pages 056 - 27pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM
Abstract The freeze-in production of Feebly Interacting Massive Particle (FIMP) dark matter in the early universe is an appealing alternative to the well-known – and constrained – Weakly Interacting Massive Particle (WIMP) paradigm. Although challenging, the phenomenology of FIMP dark matter has been receiving growing attention and is possible in a few scenarios. In this work, we contribute to this endeavor by considering a Z ' portal to fermionic dark matter, with the Z ' having both vector and axial couplings and a mass ranging from MeV up to PeV. We evaluate the bounds on both freeze-in and freeze-out from direct detection, atomic parity violation, leptonic anomalous magnetic moments, neutrino-electron scattering, collider, and beam dump experiments. We show that FIMPs can already be tested by most of these experiments in a complementary way, whereas WIMPs are especially viable in the Z ' low mass regime, in addition to the Z ' resonance region. We also discuss the role of the axial couplings of Z ' in our results. We therefore hope to motivate specific realizations of this model in the context of FIMPs, as well as searches for these elusive dark matter candidates.
Address [Cosme, Catarina; Dutra, Maira; Godfrey, Stephen; Gray, Taylor] Carleton Univ, Ottawa Carleton Inst Phys, 1125 Colonel By Dr, Ottawa, ON K1S 5B6, Canada, Email: catarina.cosme@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:000695081900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4962
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