Talk detail

Participant	Mandic, Vuk
Institution	University of Minnesota - 116 Church St SE - Minneapolis - MN - USA

Session	AP1	Accepted		Order	Time
Talk	Oral abstract	Title	Cryogenic Dark Matter Search: Recent Results and Future Prospects
Co-authors
Abstract	Cryogenic Dark Matter Search (CDMS) experiment is designed to search for dark matter in the form of Weakly Interacting Massive Particles (WIMPs). For this purpose, CDMS deploys germanium-based detectors cooled to cryogenic temperatures (~50 mK), equipped with both ionization and phonon sensors. The recently completed CDMS II experiment operated 4 kg of total germanium target mass in the Soudan mine, USA. Data acquired by CDMS II has been analyzed in several dark matter searches, including the standard low-background search, the search with reduced energy threshold, and the annual modulation search. No evidence for WIMP-nucleon spin-independent elastic scattering was found. A new experiment, SuperCDMS, is currently operating fifteen germanium detectors with interleaved ionization and phonon sensor technology. With superior background rejection provided by the new technology, and with the total target mass of 10 kg, SuperCDMS aims to reach WIMP-nucleon elastic scattering cross section of about 5e-45 cm^2 for a 60 GeV WIMP, a nearly ten-fold improvement as compared to the CDMS II experiment. I will summarize the recent CDMS II results and the status of the ongoing SuperCDMS run. I will also discuss plans to increase the SuperCDMS detector payload to 100 kg of germanium target mass and operate it at SNOlab, yielding another 10-fold improvement in the sensitivity of the dark matter searches.

Session	GW4	Accepted		Order	Time
Talk	Oral abstract	Title	Studying Newtonian Noise in an Underground Environment with the Seismometer Array at the Homestake Mine
Co-authors
Abstract	It has been argued that probing the 0.1-10 Hz frequency band of the gravitational-wave spectrum has tremendous scientific potential, both in terms of accessing new types of gravitational-wave sources and in terms of enabling a variety of cosmological observations. The third-generation gravitational-wave detectors are therefore aiming at extending the sensitive frequency band down to 1 Hz or below. This is challenging since several noise sources dominate the detector sensitivity at frequencies below 10 Hz. One of these noise sources is Newtonian noise - motion of local masses induces fluctuations in the local gravitational field, which in turn jitters the detector's test masses and masks the true gravitational-wave signals. Newtonian noise is generated by the seismic motion of the ground, atmospheric fluctuations, and human activity. Each of these three Newtonian noise sources is expected to be significantly suppressed underground, which makes underground environment particularly attractive for the third-generation detectors. In order to quantify the advantages of the underground environment, we are developing a three-dimensional array of high-sensitivity broadband seismometers in the Homestake mine, USA. With ~1.5 km available depth and vast horizontal extent, this mine is well suited to conduct unique detailed studies of how the seismic field changes with depth, including the amplitude suppression, increase in correlation length, effects of scattering and reflection off of fault lines and surface topography and others. I will summarize some of the recent results obtained with this array, as well as plans for its future development.

Session	GW1	Accepted		Order	Time
Talk	Oral abstract	Title	Stochastic Gravitational Wave Background
Co-authors
Abstract	Stochastic gravitational wave background (SGWB) is expected to arise from the superposition of gravitational-wave signals from many uncorrelated and unresolvable sources. The SGWB could be of cosmological origin, for example generated during the inflationary phase in the early universe or by cusps and kinks in cosmic (super)strings. It could also be of astrophysical origin, for example generated by summing up contributions from coalescences of all binary neutron stars and binary black holes throughout the universe. Some of these SGWB models predict a gravitational wave spectrum that may be observable by the upcoming second-generation gravitational-wave detectors (Advanced LIGO, Advanced Virgo, GEO-HF, KAGRA). I will review the current status of the SGWB modelling, and the prospects for detecting the SGWB with the second-generation detectors.