BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//LBNL Physics Division Research Progress Meetings - ECPv6.8.3//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-ORIGINAL-URL:https://rpm.physics.lbl.gov
X-WR-CALDESC:Events for LBNL Physics Division Research Progress Meetings
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:America/Los_Angeles
BEGIN:DAYLIGHT
TZOFFSETFROM:-0800
TZOFFSETTO:-0700
TZNAME:PDT
DTSTART:20190310T100000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0700
TZOFFSETTO:-0800
TZNAME:PST
DTSTART:20191103T090000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20190606T160000
DTEND;TZID=America/Los_Angeles:20190606T170000
DTSTAMP:20260415T140000
CREATED:20190507T092018Z
LAST-MODIFIED:20190507T092018Z
UID:1065-1559836800-1559840400@rpm.physics.lbl.gov
SUMMARY:Nathan Jurek (U. Oxford) "Observation of CP violation in charm decays (and more charming topics)"
DESCRIPTION:Precision measurements of the violation of charge-parity (CP) symmetry are crucial for testing the Standard Model and are sensitive probes for new physics contributions. While CP violation has been well-established by several different experiments in the decays of mesons containing strange and bottom quarks\, searches for CP violation in the decays of charm mesons had until recently come up empty-handed. Thanks to its unprecedentedly large samples of charm mesons\, the LHCb collaboration has succeeded in observing CP violation in the charm sector for the first time via a time-integrated analysis of D0→K−K+ and D0→π−π+ decays. These results will be presented\, along with recent time-dependent measurements which help constrain additional sources of CP violation in neutral charm mesons. Finally\, projections of future prospects in charm physics will be given.
URL:https://rpm.physics.lbl.gov/event/nathan-jurek-u-oxford-observation-of-cp-violation-in-charm-decays-and-more-charming-topics/
LOCATION:HYBRID 50A-5132 (Sessler Conference Room)\, https://lbnl.zoom.us/j/91782268585\, 50A-5132
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20190618T160000
DTEND;TZID=America/Los_Angeles:20190618T170000
DTSTAMP:20260415T140000
CREATED:20190611T114449Z
LAST-MODIFIED:20190611T114449Z
UID:1079-1560873600-1560877200@rpm.physics.lbl.gov
SUMMARY:Daniel Santos (LPSC) "Directional Direct Dark Matter Detection and Neutrino Spectroscopy with MIMAC"
DESCRIPTION:ABSTRACT:\n \nThe hypothesis of the existence of non-baryonic dark matter in our galactic halo is supported by all astrophysical observations performed from cosmological to local scales. The measurement of one clear experimental signal of this matter represents one of the most important challenges for physics today. The direct detection of an elastic collision with a target nucleus of a weakly interacting massive particle (WIMP)\, the most accepted candidate for such a matter\, has to be discriminated from those produced by neutrons and neutrinos\, which produce the same expected signal. The only non-ambiguous signature to be able to discriminate the WIMP events from neutrons-induced events is to correlate these elastic collisions in the detector with the relative motion of our Solar system with respect to the galactic halo. The measurement of thedirection of the nuclear recoil track in 3D of a few tens of keV is called “directional detection”. The directional detection opens a new field in cosmology: it brings the possibility to build a map of nuclear recoils exploring the galactic halo and gives access to a particle characterization of dark matter. The MIMAC (MIcro-tpc MAtrix of Chambers) collaboration has developed in the last years an original prototype detector based on the direct coupling of a pixelized Micromegas with a special developed fast self-triggered electronics showing the feasibility of a new generation of directional detectors. The flexibility of the MIMAC detector to change the nucleus target\, changing its mass and spin\, makes possible to adapt the search of candidates proposed by the large mass direct detection projects as LUX\, Xenon1T\, SCDMS or Edelweiss. In the next years\, these large mass detectors will either detect some candidates or the neutrino background floor will limit them. In both cases a directional detector will be needed to confirm the galactic halo origin of such candidates or to go further the neutrino background. The MIMAC angular resolution measured coupling one of the chambers with COMIMAC\, a dedicated facility developed allowing ionization quenching factor measurements and electron calibration\, will be shown. The localization of the 3D track by the cathode signal will be described and the new possibilities open by this new directional detector in the neutron spectroscopy will be illustrated.\n \n 
URL:https://rpm.physics.lbl.gov/event/daniel-santos-lpsc-tba/
LOCATION:HYBRID 50A-5132 (Sessler Conference Room)\, https://lbnl.zoom.us/j/91782268585\, 50A-5132
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/Los_Angeles:20190620T160000
DTEND;TZID=America/Los_Angeles:20190620T170000
DTSTAMP:20260415T140000
CREATED:20190611T114350Z
LAST-MODIFIED:20190611T114350Z
UID:1077-1561046400-1561050000@rpm.physics.lbl.gov
SUMMARY:Tucker Elliott (UCSD) "Characterization of Multiplexed Transition Edge Sensor Bolometers for the POLARBEAR-2 Cosmic Microwave Background Experiment"
DESCRIPTION:ABSTRACT:\nMeasurements of the Cosmic Microwave Background (CMB) temperature anisotropies and E-mode polarization have proven to be essential to our understanding of early universe cosmology by providing independent and strong evidence in favor of the Lambda-CDM cosmological model. However\, there is still untapped information in the CMB. Current-generation CMB experiments aim to measure the very faint B-mode polarization signal in order to find evidence of cosmic inflation and to measure the sum of the neutrino masses.\nPOLARBEAR-2 (PB-2) is a CMB polarization experiment located in northern Chile’s Atacama Desert at an altitude of 5\,200 meters. PB-2 is currently operating with over 7\,500 superconducting Transition Edge Sensor (TES) bolometers with a scheduled increase to over 22\,000 TES bolometers in the next year. PB-2 uses Digital Frequency Division Multiplexed (DfMux) readout to combine the bias and readout lines for sets of forty detectors onto a single pair of conductors in order to reduce cost and cryogenic complexity.\nSuperconducting (TES) bolometers are the gold-standard technology for observing the CMB because they can be used to make photon noise limited measurements. This is why CMB experiments continue to increase their detector counts – to achieve higher sensitivity. However in order to achieve optimal sensitivity\, the TES and multiplexing system must meet certain specifications. In this talk\, I will describe the requirements imposed on the detectors and readout system and the measurements I have performed at the University of California San Diego to characterize the detectors and readout system of the first and second PB-2 cryogenic receivers.
URL:https://rpm.physics.lbl.gov/event/tucker-elliott-ucsd-tba/
LOCATION:HYBRID 50A-5132 (Sessler Conference Room)\, https://lbnl.zoom.us/j/91782268585\, 50A-5132
END:VEVENT
END:VCALENDAR