|
Baker, M. J., Bordes, J., Dominguez, C. A., Peñarrocha, J., & Schilcher, K. (2014). B meson decay constants f(Bc), f(Bs) and f(B) from QCD sum rules. J. High Energy Phys., 07(7), 032–16pp.
Abstract: Finite energy QCD sum rules with Legendre polynomial integration kernels are used to determine the heavy meson decay constant f(Bc), and revisit f(B) and f(Bs). Results exhibit excellent stability in a wide range of values of the integration radius in the complex squared energy plane, and of the order of the Legendre polynomial. Results are f(Bc) = 528 +/- 19 MeV, f(B) = 186 +/- 14 MeV, and f(Bs) = 222 +/- 12 MeV.
|
|
|
Gnendiger, C., Signer, A., Stockinger, D., Broggio, A., Cherchiglia, A. L., Driencourt-Mangin, F., et al. (2017). To d, or not to d: recent developments and comparisons of regularization schemes. Eur. Phys. J. C, 77(7), 471–39pp.
Abstract: We give an introduction to several regularization schemes that deal with ultraviolet and infrared singularities appearing in higher-order computations in quantum field theories. Comparing the computation of simple quantities in the various schemes, we point out similarities and differences between them.
|
|
|
ANTARES Collaboration(Albert, A. et al), Barrios-Marti, J., Coleiro, A., Hernandez-Rey, J. J., Illuminati, G., Lotze, M., et al. (2017). Search for relativistic magnetic monopoles with five years of the ANTARES detector data. J. High Energy Phys., 07(7), 054–19pp.
Abstract: A search for magnetic monopoles using five years of data recorded with the ANTARES neutrino telescope from January 2008 to December 2012 with a total live time of 1121 days is presented. The analysis is carried out in the range beta > 0.6 of magnetic monopole velocities using a strategy based on run-by-run Monte Carlo simulations. No signal above the background expectation from atmospheric muons and atmospheric neutrinos is observed, and upper limits are set on the magnetic monopole flux ranging from 5.7 x 10(-16) to 1.5 x 10(-18) cm(-2).s(-1).sr(-1).
|
|
|
Arguelles, C. A., Palomares-Ruiz, S., Schneider, A., Wille, L., & Yuan, T. L. (2018). Unified atmospheric neutrino passing fractions for large-scale neutrino telescopes. J. Cosmol. Astropart. Phys., 07(7), 047–41pp.
Abstract: The atmospheric neutrino passing fraction, or self-veto, is defined as the probability for an atmospheric neutrino not to be accompanied by a detectable muon from the same cosmic-ray air shower. Building upon previous work, we propose a redefinition of the passing fractions by unifying the treatment for muon and electron neutrinos. Several approximations have also been removed. This enables performing detailed estimations of the uncertainties in the passing fractions from several inputs: muon losses, cosmic-ray spectrum, hadronic-interaction models and atmosphere-density profiles. We also study the passing fractions under variations of the detector configuration: depth, surrounding medium and muon veto trigger probability. The calculation exhibits excellent agreement with passing fractions obtained from Monte Carlo simulations. Finally, we provide a general software framework to implement this veto technique for all large-scale neutrino observatories.
|
|
|
Lara, I., Lopez-Fogliani, D. E., Muñoz, C., Nagata, N., Otono, H., & Ruiz de Austri, R. (2018). Looking for the left sneutrino LSP with displaced-vertex searches. Phys. Rev. D, 98(7), 075004–17pp.
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.
|
|
|
Yao, D. L., Alvarez-Ruso, L., Hiller Blin, A. N., & Vicente Vacas, M. J. (2018). Weak pion production off the nucleon in covariant chiral perturbation theory. Phys. Rev. D, 98(7), 076004–25pp.
Abstract: Weak pion production off the nucleon at low energies has been systematically investigated in manifestly relativistic baryon chiral perturbation theory with explicit inclusion of the Delta(1232) resonance. Most of the involved low-energy constants have been previously determined in other processes such as pion-nucleon elastic scattering and electromagnetic pion production off the nucleon. For numerical estimates, the few remaining constants are set to be of natural size. As a result, the total cross sections for single pion production on neutrons and protons, induced either by neutrino or antineutrino, are predicted. Our results are consistent with the scarce existing experimental data except in the nu(mu)n -> mu(-)n pi(+) channel, where higher-order contributions might still be significant. The Delta resonance mechanisms lead to sizeable contributions in all channels, especially in nu(mu)p -> mu(-) p pi(+), even though the considered energies are close to the production threshold. The present study provides a well-founded low-energy benchmark for phenomenological models aimed at the description of weak pion production processes in the broad kinematic range of interest for current and future neutrino-oscillation experiments.
|
|
|
De Romeri, V., Patel, K. M., & Valle, J. W. F. (2018). Inverse seesaw mechanism with compact supersymmetry: Enhanced naturalness and light superpartners. Phys. Rev. D, 98(7), 075014–15pp.
Abstract: We consider the supersymmetric inverse seesaw mechanism for neutrino mass generation within the context of a low-energy effective theory where supersymmetry is broken geometrically in an extra dimensional theory. It is shown that the effective scale characterizing the resulting compact supersymmetric spectrum can be as low as 500-600 GeV for moderate values of tan beta. The potentially large neutrino Yukawa couplings, naturally present in inverse seesaw schemes, enhance the Higgs mass and allow the superpartners to be lighter than in compact supersymmetry without neutrino masses. The inverse seesaw structure also implies a novel spectrum profile and couplings, in which the lightest supersymmetric particle can be an admixture of isodoublet and isosinglet sneutrinos. Dedicated collider as well as dark matter studies should take into account such specific features.
|
|
|
Nath, N., Srivastava, R., & Valle, J. W. F. (2019). Testing generalized CP symmetries with precision studies at DUNE. Phys. Rev. D, 99(7), 075005–13pp.
Abstract: We examine the capabilities of the DUNE experiment in probing leptonic CP violation within the framework of theories with generalized CP symmetries characterized by the texture zeros of the corresponding CP transformation matrices. We investigate DUNE's potential to probe the two least known oscillation parameters, the atmospheric mixing angle theta(23) and the Dirac CP phase delta(CP). We fix theory-motivated benchmarks for (sin(2)theta(23), delta(CP)) and take them as true values in our simulations. Assuming 3.5 years of neutrino running plus 3.5 years in the antineutrino mode, we show that in all cases DUNE can significantly constrain and in certain cases rule out the generalized CP texture zero patterns.
|
|
|
Cordero-Carrion, I., Hirsch, M., & Vicente, A. (2019). Master Majorana neutrino mass parametrization. Phys. Rev. D, 99(7), 075019–6pp.
Abstract: After introducing a master formula for the Majorana neutrino mass matrix, we present a master parametrization for the Yukawa matrices automatically in agreement with neutrino oscillation data. This parametrization can be used for any model that induces Majorana neutrino masses. The application of the master parametrization is also illustrated in an example model, with special focus on its lepton flavor violating phenomenology.
|
|
|
T2K Collaboration(Abe, K. et al), Antonova, M., Cervera-Villanueva, A., Fernandez, P., Izmaylov, A., & Novella, P. (2019). Search for light sterile neutrinos with the T2K far detector Super-Kamiokande at a baseline of 295 km. Phys. Rev. D, 99(7), 071103–10pp.
Abstract: We perform a search for light sterile neutrinos using the data from the T2K far detector at a baseline of 295 km, with an exposure of 14.7(7.6) x 10(20) protons on target in neutrino (antineutrino) mode. A selection of neutral-current interaction samples is also used to enhance the sensitivity to sterile mixing. No evidence of sterile neutrino mixing in the 3 + 1 model was found from a simultaneous fit to the charged-current muon, electron and neutral-current neutrino samples. We set the most stringent limit on the sterile oscillation amplitude sin(2)theta(24 )for the sterile neutrino mass splitting Delta m(41)(2 )< 3 x 10(-3 )eV(2)/c(4).
|
|