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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. Source

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. Source

Sivers M.V.,TU Munich | Sivers M.V.,University of Bern | Clark M.,Queens University | Di Stefano P.C.F.,Queens 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. Source

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. Source

Strauss R.,TU Munich | Strauss R.,Max Planck Institute for Physics | Angloher G.,Max Planck Institute for Physics | Bento A.,University of Coimbra | And 38 more authors.
European Physical Journal C | Year: 2014

ScintillatingCaWO4 single crystals are a promising multi-element target for rare-event searches and are currently used in the direct dark matter experiment CRESST (Cryogenic Rare Event Search with Superconducting Thermometers). The relative light output of different particle interactions in CaWO4 is quantified by quenching factors (QFs). These are essential for an active background discrimination and the identification of a possible signal induced by weakly interacting massive particles (WIMPs). We present the first precise measurements of the QFs of O, Ca and W at mK temperatures by irradiating a cryogenic detector with a fast neutron beam. A clear energy dependence of the QF of O and, less pronounced, of Ca was observed for the first time. Furthermore, in CRESST neutron-calibration data a variation of the QFs among different CaWO4 single crystals was found. For typical CRESST detectors the QFs in the region-of-interest (10–40 keV) are QF ROI O = (11.2±0.5) %, QFROI Ca = (5.94±0.49)%and QFROI W= (1.72±0.21) %. The latest CRESST data (run32) is reanalyzed using these fundamentally new results on light quenching in CaWO4 having moderate influence on the WIMP analysis. Their relevance for future CRESST runs and for the clarification of previa © The Author(s) 2014. Source

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