Polytetrafluoroethylene (PTFE) is an excellent diffuse reflector widely used in light collection systems for particle physics experiments. In noble element systems, it is often coated with tetraphenyl butadiene (TPB) to allow detection of vacuum ultraviolet scintillation light. In this work this dependence is investigated for PTFE coated with TPB in air for light of wavelengths of 200 nm, 260 nm, and 450 nm. Th...
We present a tunable metal ion beam that delivers controllable ion currents in the picoamp range for testing of dry-phase ion sensors. Ion beams are formed by sequential atomic evaporation and single or multiple electron impact ionization, followed by acceleration into a sensing region. Controllability of the ionic charge state is achieved through tuning of electrode potentials that influence the retention time...
POPULAR SUMMARY When ionizing radiation interacts with xenon, copious amounts of ultraviolet light are emitted at particular wavelengths—an “electroluminescence” that is leveraged in dark matter searches and neutrino detectors. But researchers were not aware of the presence of another, fainter, light emission over a broader wavelength range, from the ultraviolet to the near infrared. Therefore, scientists expla...
Made available in DSpace on 2022-04-29T07:28:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-02-12; We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132...
Made available in DSpace on 2022-04-29T07:30:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-02-17; National Science Foundation; We report results of a wideband search for periodic gravitational waves from isolated neutron stars within the Orion spur towards both the inner and outer regions of our Galaxy. As gravitational waves interact very weakly with matter, the search is unimpeded by dust and conc...
Made available in DSpace on 2022-04-29T07:31:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-02-25; In this paper we present the results of the first low frequency all-sky search of continuous gravitational wave signals conducted on Virgo VSR2 and VSR4 data. The search covered the full sky, a frequency range between 20 and 128 Hz with a range of spin-down between -1.0×10-10 and +1.5×10-11 Hz/s, and wa...
Made available in DSpace on 2022-04-29T07:32:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-03-31; Following a major upgrade, the two advanced detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO) held their first observation run between September 2015 and January 2016. With a strain sensitivity of 10-23/Hz at 100 Hz, the product of observable volume and measurement time exceede...
Made available in DSpace on 2022-04-29T07:34:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-03-31; The LIGO detection of the gravitational wave transient GW150914, from the inspiral and merger of two black holes with masses 30M, suggests a population of binary black holes with relatively high mass. This observation implies that the stochastic gravitational-wave background from binary black holes, cre...
Made available in DSpace on 2022-04-29T07:35:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-05-31; Science and Technology Facilities Council; The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativisti...
Made available in DSpace on 2022-04-29T07:37:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-06-07; European Commission; Istituto Nazionale di Fisica Nucleare; Ministry of Science and Technology; Directorate for Mathematical and Physical Sciences; National Research Foundation of Korea; National Stroke Foundation; Hungarian Scientific Research Fund; Russian Foundation for Basic Research; Scottish Fundi...