CPT

Calendar of Physics Talks Vienna

Highly charged ions for probing the time variation of the fine-structure constant
Speaker:PD Dr. José Ramón Crespo López-Urrutia (Max Planck Institute for Nuclear Physics, Heidelberg)
Abstract:Sympathetically cooled highly charged ions (HCI) can improve the operation of optical clocks in order to set new limits on possible variations of the fine-structure constant in space or time. A variation of this fundamental constant has been claimed based on astrophysical observations, yet its magnitude is still too small for laboratory consistency checks. The currently best benchmarks are based on comparing frequencies of different optical clocks with a relative accuracy of 10-17 per year. Forbidden optical transitions in HCI offer major advantages as optical frequency references. Compared with atoms or singly charged ions, their deeply bound optically active electron shows greatly reduced systematic shifts by external perturbations, such as those due to interrogation by lasers or blackbody radiation. At the same time, .... [full abstract on https://indico.smi.oeaw.ac.at/event/138/]
Date: Wed, 30.03.2016
Time: 17:00
Duration: 60 min
Location:Stefan-Meyer-Institut, Boltzmanngasse 3, 1090 Wien, Seminarraum 3-2-08 (2. Stock)
Contact:Prof. Dr. Eberhard Widmann, Dr. Martin Simon

Natural SUSY: LHC and Dark Matter direct detection experiments interplay
Speaker:Werner Porod (University of Würzburg)
Abstract:We explore a Natural Supersymmetry (NSUSY) scenarios. The first one has a rather low value for the mu-parameter. This implies higgsino-like dark matter (DM) and a compressed spectrum for the lightest states. This scenario could be probed via monojet signatures, but as the signal to-background ratio (S/B) is low we demonstrate that the 8 TeV LHC does not imply limits on the DM mass beyond those of LEP2. At the 13 TeV run one can obtain bounds on the DM mass of the order of 200 GeV by optimising the kinematical cuts. Moreover, we find that LUX/XENON1T and LHC do play complementary roles in exploring the parameter space of NSUSY in this class of models. The second class of NSUSY models, that we will discuss, contains an R-sneutrino as LSP.
Date: Fri, 01.04.2016
Time: 10:30
Duration: 60 min
Location:Institute of High Energy Physics, Nikolsdorfer Gasse 18, 1050 Wien / Library, 1st floor
Contact:Helmut.Eberl@oeaw.ac.at