Announcements

Here are current and past announcement for the USERS seminars.

3rd May 2012 Seminar

posted Apr 26, 2012, 12:43 PM by Ryan Martin   [ updated Apr 26, 2012, 12:44 PM ]

Date: 5/3/2012 at 1:30pm
Location: LBNL, 50-5014 Conference Room
Speaker: Andzej Drukier
Title: New detectors for WIMPs

Abstract:
We suggest that the combination of nano-technology and molecular biology permits two new classes of WIMPs detectors.
The extension of old superconducting grains to now possible superconducting nano-rods may permit non-directional , cryogenic detectors with M+ 10 kg of W and energy threshold of 0.1 keV.
The new concept of SSDNA as supersensitive ROOM TEMPERATURE Wimps detector permits directional detection with the following parameters:
1) 0.5 x 0.5 x 0.5 m**3; ( 1 kg Au and 1 kg of DNA)
2) spatial resolution of better than 10 degree;
3) energy threshold of about 1 keV.
Both detectors are based on proprietary, innovative combination of nano-technology and molecular biology.  The main uncertainty, as usual ,are signal/background considerations.

19th April 2012 Seminar

posted Apr 16, 2012, 7:45 AM by Ryan Martin   [ updated Apr 16, 2012, 7:46 AM ]

Date: 4/19/2012 at 13:30 (sharp)
Location: UCB Old LeConte Hall, OLC 325
Speaker: Jason Detwiler (LBNL)
Title: First Results from KamLAND-Zen

Astract: This talk will present the recent measurement of 136Xe double-beta
decay by KamLAND-Zen. Results for both the two-neutrino and
neutrinoless modes will be discussed, along with important features in
the background spectrum Special attention will be paid to the
appearance of an unexpected background peak just above the Q-value of
the decay, and prospects for its mitigation. Future plans and
sensitivity projections will also be presented.

March 22nd 2012 Seminar

posted Mar 19, 2012, 12:20 PM by Ryan Martin   [ updated Mar 19, 2012, 12:25 PM ]


Date: 3/22/2012 at 13:30 (sharp)
Location: UCB Old LeConte Hall, OLC 325
Speaker: Dr. Raul Hennings-Yeomans (LANL)
Title: Testing the path to a multi-tonne Dark Matter search with MiniCLEAN
Abstract:
The particle nature of dark matter remains one of the biggest challenges in Astroparticle physics today. The use of liquid noble elements as scintillators for direct detection of dark matter in single and dual phase configurations are one of the most promising techniques to reach sensitivities beyond 10−44 cm2 in spin-independent WIMP-nucleon cross section. MiniCLEAN (CLEAN- Cryogenic Low Energy  strophysics
with Noble Gases) is an approximately spherical 500 kg liquid argon or neon vessel that encloses 92 optical cassettes (modular photo-detectors) pointing at the center of the sphere through a TPB (Tetraphenyl Butadine) evaporated window that converts  UV light from the argon or neon scintillation into the visible. The modular spherical design allows both for a viable radon-mitigated assembly and for position  econstruction. Furthermore, the use of Pulse-Shape discrimination techniques between nuclear and electronic recoils that are particularly good for these two noble gases will test the single-phase approach as a viable instrument for direct detection of dark matter at the multi-tonne scale with a projected sensitivity of 10−46 cm2 for a ∼100 GeV/c2 WIMP mass in terms of spin-independent WIMP-nucleon cross section. I will be presenting a review and status of the MiniCLEAN research program as well as new developments in the mitigation of depth-dependent and radiogenic neutron backgrounds.

February 9th 2012 Seminar

posted Feb 2, 2012, 8:33 AM by Ryan Martin   [ updated Feb 6, 2012, 8:02 AM ]

  Location: 425 OLC (Old LeConte Hall, UCB)

Time: 1:30pm, refreshments at 1:15pm

Speaker:  Azriel Goldschmidt (LBNL)

Title: Xenon electroluminescent TPC for precise energy measurement and ionization track imaging

Abstract:

At LBNL we have built a high-pressure xenon electroluminescent Time Projection
Chamber (TPC). In it ionization electrons drift to a region where they each produce
O(1000) UV photons. A fraction of these photons are detected by an array of
photo-multipliers inside the high-pressure volume providing a measurement of the
total energy deposited with high statistical precision. For 662 keV gamma rays from
137Cs we have obtained a 1% FWHM energy resolution. in addition, an array of silicon
photo-multipliers (SiPMs or MPPCs) will soon be installed near the light production region
to produce signals that enable the reconstruction of the ionization tracks.
This is a prototype device towards a 100 kg enriched 136Xe NEXT experiment for the
search of neutrino-less double beta decay.

January 26th 2012 Seminar

posted Jan 23, 2012, 4:22 PM by Ryan Martin   [ updated Mar 5, 2012, 4:21 PM ]

Location: 50A-5132 (LBNL)

Speaker: Matt Pyle (Stanford University/University of California Berkeley)

Title: Creating Large Mass Athermal Phonon Detectors with 1-10eV Trigger Thresholds for Coherent ν-N scattering and Exotic Dark Matter Applications

Abstract:

The measurement of coherent neutrino-nucleus scattering for sterile neutrino and non-standard model interaction searches, as well as searches for many exotic dark matter candidates share a single unsolved technical difficulty: the need to measure very small excitations (1-100eV nuclear recoils or a single e-/h+) in massive detectors.The use of athermal phonon detector technology to solve this problem seems natural since athermal phonons can be collected and concentrated into very small sensor volumes unlike thermal phonons and thus energy resolution and trigger threshold do not directly scale with the target mass.  Secondly, by operating with a high voltage bias, one can convert electrostatic potential energy into Luke-Neganov phonons and thus significantly gain the athermal phonon signal. In this talk, we’ll discuss the reasons why the current CDMS detectors do not meet the necessary requirements and we’ll propose a threshold optimized design which could potentially achieve 1-10eV phonon trigger thresholds or equivalently single e-/h+ sensitivity.

January 12th 2012 Seminar

posted Jan 4, 2012, 1:04 PM by Ryan Martin   [ updated Jan 4, 2012, 1:06 PM ]

Location: 50B-4205 (LBNL)
Speaker: Chang Hyon Ha (LBNL-NSD)
Title : Observation of Atmospheric Neutrino-Induced Cascades in IceCube with DeepCore
Abstract :The recently completed IceCube neutrino observatory is composed of more than 5,000 digital optical modules attached to 86 strings and buried in the South Pole ice. The observatory includes a tightly spaced inner array in the deepest ice, called DeepCore, which allows detection of low-energy neutrinos over a 4π solid angle with a giant surrounding cosmic ray muon veto. Designed to be sensitive to neutrinos at energies below 1 TeV, DeepCore collects a very high flux of atmospheric neutrinos which can be used to study neutrino flavor identification and oscillation physics. For the first time, atmospheric neutrino-induced cascades are observed in IceCube, using the 79-string detector with the DeepCore extension. Using 281 days of full data, 1029 events are observed of which 59% are predicted to be cascades. The first year performance of the detector, this observation, and future analyses are discussed in this presentation.

December 15th Seminar

posted Dec 13, 2011, 8:34 AM by Ryan Martin   [ updated Dec 13, 2011, 8:34 AM ]

Location: 325 Old Leconte Hall Berkeley Campus
Speaker: Kathryn Zurek (University of Michigan)
Title: Asymmetric Dark Matter
Abstract: The observed ratio of baryon to dark matter energy densities is a factor of five, though within the standard paradigms of dark matter, there is no explanation for this fact.  We discuss models, under the name of Asymmetric Dark Matter, which give rise to this ratio naturally.

December 1st seminar cancelled

posted Nov 28, 2011, 2:26 AM by Ryan Martin   [ updated Nov 28, 2011, 2:26 AM ]

Due to Thanksgiving travel, the seminar on 1st December has been cancelled

November 17th Seminar

posted Nov 10, 2011, 11:49 AM by Ryan Martin   [ updated Nov 10, 2011, 11:49 AM ]

Location: 325 Old Leconte Hall Berkeley Campus
Speaker: Beate Heinemann
Title: SUSY Searches at the LHC
Abstract: We will summarize the status of searches for Supersymmetry (SUSY) at the LHC. SUSY is among the most prominent candidates for a theory that explains Dark Matter, and in particular WIMPs. We will discuss the searches that are currently being performed at the LHC in general and their impact on WIMP masses in particular.

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