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Eberl H.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften | Ginina E.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften | Bartl A.,University of Vienna | Hidaka K.,Tokyo Gakugei University | Majerotto W.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften
Journal of High Energy Physics | Year: 2016

We calculate the decay width of h0→ bb¯ in the Minimal Supersymmetric Standard Model (MSSM) with quark flavour violation (QFV) at full one-loop level. We study the effect of c˜ − t˜ mixing and s˜ − b˜ mixing taking into account the constraints from the B meson data. We discuss and compare in detail the decays h0→ cc¯ and h0→ bb¯ within the framework of the perturbative mass insertion technique using the Flavour Expansion Theorem. The deviation of both decay widths from the Standard Model values can be quite large. Whereas in h0→ cc¯ it is almost entirely due to the flavour violating part of the MSSM, in h0→ bb¯ it is mainly due to the flavour conserving part. Nevertheless, the QFV contribution to Γ(h0→ bb¯)due to c˜ − t˜ mixing and chargino exchange can go up to ∼ 7%. © 2016, The Author(s).

Bartl A.,University of Vienna | Eberl H.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften | Ginina E.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften | Hidaka K.,Tokyo Gakugei University | And 2 more authors.
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We compute the decay width of h0→cc¯ in the minimal supersymmetric Standard Model with quark flavor violation (QFV) at full one-loop level adopting the DR¯ renormalization scheme. We study the effects of c-t mixing, taking into account the constraints from the B meson data. We show that the full one-loop corrected decay width Γ(h0→cc¯) is very sensitive to the minimal supersymmetric Standard Model QFV parameters. In a scenario with large cL,R-tL,R mixing Γ(h0→cc¯) can differ up to ∼±35% from its Standard Model value. After estimating the uncertainties of the width, we conclude that an observation of these supersymmetry QFV effects is possible at an e+e- collider (International Linear Collider). © 2015 American Physical Society.

Bartl A.,University of Vienna | Eberl H.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften | Herrmann B.,German Electron Synchrotron | Herrmann B.,University of Würzburg | And 4 more authors.
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2011

We study the effect of squark generation mixing on squark production and decays at LHC in the Minimal Supersymmetric Standard Model (MSSM). We show that the effect can be very large despite the very strong constraints on quark-flavour violation (QFV) from experimental data on B mesons. We find that the two lightest up-type squarks u~1,2 can have large branching ratios for the decays into cχ~10 and tχ~10 at the same time due to squark generation mixing, leading to QFV signals '. pp→ct-(tc-)+missing-ET+X' with a significant rate. The observation of this remarkable signature would provide a powerful test of supersymmetric QFV at LHC. This could have a significant impact on the search for squarks and the determination of the underlying MSSM parameters. © 2011 Elsevier B.V.

Bartl A.,University of Vienna | Eberl H.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften | Ginina E.,University of Vienna | Herrmann B.,University of Savoy | And 3 more authors.
International Journal of Modern Physics A | Year: 2014

We study quark flavor violation (QFV) in the squark sector of the Minimal Supersymmetric Standard Model (MSSM). We assume mixing between the second and the third squark generations, i.e. $\tilde{c} {R}-\tilde{t} {L, R}$ mixing. We focus on QFV effects in bosonic squark decays, in particular on the decay into the lightest Higgs boson $h0$, $\tilde{u} 2 \to \tilde{u} 1 h0$, where $\tilde{u} {1, 2}$ are the lightest up-type squarks. We show that the branching ratio of this QFV decay can be quite large (up to 50%) due to large QFV trilinear couplings, and large $\tilde{c} {R}-\tilde{t} {L, R}$ and $\tilde{t} {L}-\tilde{t} {R}$ mixing, despite the strong constraints on QFV from B meson data. This can result in characteristic QFV final states with significant rates at LHC (14 TeV), such as $pp \to \tilde{g} \tilde{g} X \to t + h0 + 3∼{\rm jets}+{\sslE} T + X$ and $pp \to \tilde{g} \tilde{g} X \to t t$ $({\rm or}∼\bar{t}\bar{t}) + h0 + 2∼{\rm jets} + {\sslE} T + X$. The QFV bosonic squark decays can have an influence on the squark and gluino searches at LHC. © 2014 World Scientific Publishing Company.

Eberl H.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften | Spanos V.C.,National and Kapodistrian University of Athens
Computer Physics Communications | Year: 2016

We present the package GravitinoPack that calculates the two- and three-body decays of unstable supersymmetric particles involving the gravitino in the final or initial state. In a previous paper, we already showed results for the gravitino decaying into two and three particles. In this paper, we incorporate the processes where an unstable neutralino, stau or stop decays into a gravitino and Standard Model particles. This is the case in gravitino dark matter supersymmetric models, where the gravitino is the lightest SUSY particle. We give instructions for the installation and the use of the package. In the numerical analysis, we discuss various MSSM scenarios. We show that the calculation of all the decay channels and the three-body decay branching ratios is essential for the accurate application of cosmological bounds on these models. Program summary: Program title: GravitinoPack. Catalogue identifier: AEZL_v1_0. Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEZL_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland. Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 97708. No. of bytes in distributed program, including test data, etc.: 1217167. Distribution format: tar.gz. Programming language: Fortran 77 and C for the MathLink. Computer: Workstation, PC, Mac. Operating system: Linux, Mac OSX. Classification: 11.1. Nature of problem: If Supersymmetry (SUSY) is realized in nature, each Standard Model (SM) particle is accompanied by its superpartner. The gravitino, the spin 3/2 superpartner of the graviton, belongs to the spectrum of the most important supersymmetric models. The gravitino can be the Lightest Supersymmetric Particle (LSP), in the so-called gravitino Dark Matter (DM) models. Thus, the Next to the Lightest Supersymmetric Particle (NLSP) is long-lived, since it decays gravitationally to the LSP (gravitino) and SM particles. Such decays produce electromagnetic energy and hadrons which can affect the primordial Big-Bang Nucleosynthesis (BBN) predictions for the abundance of the light nuclei. Similarly, when the gravitino is not the LSP it decays into the LSP which can be another SUSY particle, like the neutralino, and SM particles. GravitinoPack provides important results on all these decays, making the application of the BBN data more accurate. Solution method: GravitinoPack is a package for the evaluation of processes with gravitino interaction. The version GravitinoPack1.0 includes all two-body decays of the gravitino and all three-body decays of the gravitino to a neutralino and a pair of two particles. In the case that the gravitino is the LSP all two- and three-body decays of the lightest neutralino, the light stop or stau NLSP are included. GravitinoPack works at Fortran77 level and has a Mathematica interface. Unusual features: MathLink works properly only up to version Mathematica 9. There is still a conflict between Mathematica 10 and the used integration routine CUBA. Running time: All two-body decay widths are calculated in a time far below one second. The three-body decay calculations can be fast, especially the stop and stau decays, or slow with times up to a few minutes, especially when the phase space becomes large and no approximation is chosen. © 2016 Elsevier B.V.

Journal of High Energy Physics | Year: 2011

We study the effects of CP violation in charged Higgs boson production pp → tH- + X at the LHC, as well as in the charged Higgs boson decays H → tb and H → WH0 i, i = 1; 2; 3. The study is done in the framework of the type II complex Two Higgs Doublet Model (2HDM) with softly broken Z2 symmetry. In this model violation of CP invariance is induced by the complex parameter m2 12 of the tree-level Higgs potential. We calculate the CP violating rate asymmetries for H+ and H production and decays as well as for the combined processes at one-loop level and perform a detailed numerical analysis. All calculations are done with the automatic amplitude generator FeynArts and the calculational tool FormCalc, for which we have written a complete complex 2HDM model le and relevant fortran drivers. The implementation of the complex 2HDM in FeynArts and FormCalc is described. In comparison with the analogous results in the MSSM, all considered CP violating asymmetries are smaller by an order of magnitude and do not exceed 2 - 3%. © SISSA 2011.

Angloher G.,Max Planck Institute for Physics | Bento A.,University of Coimbra | Bucci C.,National Institute of Nuclear Physics, Italy | Canonica L.,National Institute of Nuclear Physics, Italy | And 44 more authors.
European Physical Journal C | Year: 2014

The CRESST-II cryogenic dark matter search aims for the detection of WIMPs via elastic scattering off nuclei in CaWO4 crystals. We present results from a low-threshold analysis of a single upgraded detector module. This module efficiently vetoes low energy backgrounds induced by α-decays on inner surfaces of the detector. With an exposure of 29.35 kg live days collected in 2013 we set a limit on spin-independent WIMP-nucleon scattering which probes a new region of parameter space for WIMP masses below 3 GeV/c2, previously not covered in direct detection searches. A possible excess over background discussed for the previous CRESST-II phase 1 (from 2009 to 2011) is not confirmed. © 2014, The Author(s).

Angloher G.,Max Planck Institute for Physics | Carniti P.,National Institute of Nuclear Physics, Italy | Cassina L.,National Institute of Nuclear Physics, Italy | Gironi L.,National Institute of Nuclear Physics, Italy | And 18 more authors.
European Physical Journal C | Year: 2016

The R&D project COSINUS (Cryogenic Observatory for SIgnatures seen in Next-generation Underground Searches) aims to develop a cryogenic scintillating calorimeter using an undoped NaI-crystal as target for direct dark matter search. Dark matter particles interacting with the detector material generate both a phonon signal and scintillation light. While the phonon signal provides a precise determination of the deposited energy, the simultaneously measured scintillation light allows for particle identification on an event-by-event basis, a powerful tool to study material-dependent interactions, and to suppress backgrounds. Using the same target material as the DAMA/LIBRA collaboration, the COSINUS technique may offer a unique possibility to investigate and contribute information to the presently controversial situation in the dark matter sector. We report on the dedicated design planned for the NaI proof-of-principle detector and the objectives of using this detection technique in the light of direct dark matter detection. © 2016, The Author(s).

Gutlein A.,Institute For Hochenergiephysik Der Osterreichischen Akademie Der Wissenschaften | Gutlein A.,Vienna University of Technology | Angloher G.,Max Planck Institute for Physics | Bento A.,University of Coimbra | And 40 more authors.
Astroparticle Physics | Year: 2015

Atmospheric and solar neutrinos scattering coherently off target nuclei will be an important background source for the next generation of direct dark matter searches. In this work we focus on calcium tungstate as target material. For comparison with existing works we calculate the neutrino floor indicating which sensitivities can be reached before the neutrino background appears. In addition, we investigate the sensitivities of future direct dark matter searches using CRESST-II like detectors. Extending previous works we take into account achievable energy resolutions and thresholds as well as beta and gamma backgrounds for this investigation. We show that an exploration of WIMP-nucleon cross sections below the neutrino floor is possible for exposures of ≳10 kg-years. In the third part we show that a first detection of coherent neutrino nucleus scattering of atmospheric and solar neutrinos using the same detectors and the backgrounds is feasible for exposures of ≳50 kg-years. © 2015 Elsevier B.V.

Sivers M.V.,TU Munich | Sivers M.V.,University of Bern | Clark M.,Queen's University | Di Stefano P.C.F.,Queen's University | And 18 more authors.
Journal of Applied Physics | Year: 2015

In prospect of its application in cryogenic rare-event searches, we have investigated the low-temperature scintillation properties of CaWO4 crystals down to 3.4 K under α and γ excitation. Concerning the scintillation decay times, we observe a long component in the ms range which significantly contributes to the light yield below 40 K. For the first time we have measured the temperature dependence of the α/γ-ratio of the light yield. This parameter, which can be used to discriminate α and γ events in scintillating bolometers, is found to be ∼8%-15% smaller at low temperatures compared to room temperature. © 2015 AIP Publishing LLC.