B. Welliver
A5060743205- Particle physics theoretical and experimental studies
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Astrophysics and Cosmic Phenomena
- Medical Imaging and Pathology Studies
- Radiation Detection and Scintillator Technologies
- Superconducting and THz Device Technology
- Atomic and Subatomic Physics Research
- Particle accelerators and beam dynamics
- Nuclear physics research studies
- Quantum, superfluid, helium dynamics
- Physics of Superconductivity and Magnetism
- Cosmology and Gravitation Theories
- Medical Imaging Techniques and Applications
- Scientific Research and Discoveries
- Radioactive Decay and Measurement Techniques
- Spectroscopy and Laser Applications
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Cancer Treatment and Pharmacology
- Astronomy and Astrophysical Research
- Advanced NMR Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- Muon and positron interactions and applications
Lawrence Berkeley National Laboratory
2017-2024
University of California, Berkeley
2021-2024
University of California System
2024
Massachusetts Institute of Technology
2021
Gran Sasso Science Institute
2021
Institut de Recherche sur les Lois Fondamentales de l'Univers
2021
CEA Paris-Saclay
2021
Université Paris-Saclay
2021
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2021
Université Claude Bernard Lyon 1
2021
We report a first search for weakly interacting massive particles (WIMPs) using the background rejection capabilities of SuperCDMS. An exposure 577 kg days was analyzed WIMPs with mass <30 GeV/c(2), signal region blinded. Eleven events were observed after unblinding. set an upper limit on spin-independent WIMP-nucleon cross section 1.2×10(-42) cm(2) at 8 GeV/c(2). This result is in tension WIMP interpretations recent experiments and probes new parameter space scattering masses <6
We report results of a search for weakly interacting massive particles (WIMPS) with the silicon detectors CDMS II experiment. This blind analysis 140.2 kg day data taken between July 2007 and September 2008 revealed three WIMP-candidate events surface-event background estimate 0.41(-0.08)(+0.20)(stat)(-0.24)(+0.28)(syst). Other known backgrounds from neutrons 206Pb are limited to <0.13 <0.08 at 90% confidence level, respectively. The exposure this is equivalent 23.4 recoil energy range 7-100...
The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in search for weakly interacting massive particles (WIMPs). Results are presented from second CDMSlite run with an exposure of 70 kg day, which reached energy electron recoils as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space WIMP-nucleon spin-independent cross...
SuperCDMS is an experiment designed to directly detect Weakly Interacting Massive Particles (WIMPs), a favored candidate for dark matter ubiquitous in the Universe. In this paper, we present WIMP-search results using calorimetric technique call CDMSlite, which relies on voltage- assisted Luke-Neganov amplification of ionization energy deposited by particle interactions. The data were collected with single 0.6 kg germanium detector running 10 live days at Soudan Underground Laboratory. A low...
SuperCDMS SNOLAB will be a next-generation experiment aimed at directly detecting low-mass (< 10 GeV/c$^2$) particles that may constitute dark matter by using cryogenic detectors of two types (HV and iZIP) target materials (germanium silicon). The is being designed with an initial sensitivity to nuclear recoil cross sections ~ 1 x 10$^{-43}$ cm$^2$ for particle mass GeV/c$^2$, capacity continue exploration both smaller masses better sensitivities. phonon the HV sufficient detect recoils from...
The SuperCDMS experiment is designed to directly detect weakly interacting massive particles (WIMPs) that may constitute the dark matter in our Galaxy. During its operation at Soudan Underground Laboratory, germanium detectors were run CDMSlite mode gather data sets with sensitivity specifically for WIMPs masses ${<}$10 GeV/$c^2$. In this mode, a higher detector-bias voltage applied amplify phonon signals produced by drifting charges. This paper presents studies of experimental noise and...
We report the result of a blinded search for Weakly Interacting Massive Particles (WIMPs) using majority SuperCDMS Soudan dataset. With an exposure 1690 kg days, single candidate event is observed, consistent with expected backgrounds. This analysis (combined previous Ge results) sets upper limit on spin-independent WIMP--nucleon cross section $1.4 \times 10^{-44}$ ($1.0 10^{-44}$) cm$^2$ at 46 GeV/$c^2$. These results set strongest limits WIMP--germanium-nucleus interactions masses $>$12
Abstract CUPID-Mo is a bolometric experiment to search for neutrinoless double-beta decay ( $$0\nu \beta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>0</mml:mn><mml:mi>ν</mml:mi><mml:mi>β</mml:mi><mml:mi>β</mml:mi></mml:mrow></mml:math> ) of $$^{100}\hbox {Mo}$$ xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow /><mml:mn>100</mml:mn></mml:msup><mml:mtext>Mo</mml:mtext></mml:mrow></mml:math> . In this article, we detail the detector...
The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, next-generation ton-scale bolometric $0\ensuremath{\nu}\ensuremath{\beta}\ensuremath{\beta}$ experiment. It consists of 4.2 kg array 20 enriched ${\mathrm{Li}}_{2}$$^{100}\mathrm{Mo}{\mathrm{O}}_{4}$ scintillating bolometers to search lepton-number-violating process decay in $^{100}\mathrm{Mo}$. With more than one year operation ($^{100}\mathrm{Mo}$ exposure $1.17\text{ }\text{...
Abstract The CUPID-Mo experiment to search for 0 $$\nu \beta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>ν</mml:mi> <mml:mi>β</mml:mi> </mml:mrow> </mml:math> decay in $$^{100}$$ <mml:msup> <mml:mrow /> <mml:mn>100</mml:mn> </mml:msup> Mo has been recently completed after about 1.5 years of operation at Laboratoire Souterrain de Modane (France). It served as a demonstrator CUPID, next generation experiment. was comprised 20 enriched $$\hbox {Li}_{{2}}$$...
CDMS II data from the five-tower runs at Soudan Underground Laboratory were reprocessed with an improved charge-pulse fitting algorithm. Two new analysis techniques to reject surface-event backgrounds applied 612 kg days germanium-detector weakly interacting massive particle (WIMP)-search exposure. An extended was also completed by decreasing 10 keV threshold $\ensuremath{\sim}5\text{ }\text{ }\mathrm{keV}$, increase sensitivity near a WIMP mass of $8\text{ }\mathrm{GeV}/{c}^{2}$. After...
Abstract We report the measurement of two-neutrino double-beta ( $$2\nu \beta $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>2</mml:mn><mml:mi>ν</mml:mi><mml:mi>β</mml:mi><mml:mi>β</mml:mi></mml:mrow></mml:math> ) decay $$^{100}$$ xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mrow /><mml:mn>100</mml:mn></mml:msup></mml:math> Mo to ground state Ru using lithium molybdate $$\hbox {Li}_2^{\;\;100}\hbox {MoO}_4$$...
Neutrinoless double beta decay (0νββ) is a yet unobserved nuclear process that would demonstrate Lepton number violation, clear evidence of beyond standard model physics. The two neutrino (2νββ) allowed by the and has been measured in numerous experiments. In this Letter, we report measurement 2νββ half-life Mo100 to ground state Ru100 [7.07±0.02(stat)±0.11(syst)]×1018 yr CUPID-Mo experiment. With relative precision ±1.6% most precise date rate Mo100. addition, constrain higher-order...
We report limits on annual modulation of the low-energy event rate from Cryogenic Dark Matter Search (CDMS II) experiment at Soudan Underground Laboratory. Such a could be produced by interactions Weakly Interacting Massive Particles (WIMPs) with masses ~10 GeV/c^2. find no evidence for in veto-anticoincident single-detector consistent nuclear recoils, and constrain magnitude any to <0.06 [keVnr kg day]^-1 5-11.9 keVnr energy range 99% confidence level. These results disfavor an...
We examine the consequences of effective field theory (EFT) dark matter--nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using optimum interval method are presented SuperCDMS Soudan, CDMS II, LUX, necessity combining results from multiple experiments in order to determine matter parameters is discussed. demonstrate that spectral differences between standard model a general interaction can produce bias when...
We report results of a search for Weakly Interacting Massive Particles (WIMPs) with the Si detectors CDMS II experiment. This describes blind analysis first data taken II's full complement in 2006-2007; from this exposure using Ge have already been presented. observed no candidate WIMP-scattering events an 55.9 kg-days before cuts, expected background ~1.1 events. The is equivalent to 10.3 over recoil energy range 7-100 keV ideal detector and WIMP mass 10 GeV/c2. These set upper limit...
The SuperCDMS experiment in the Soudan Underground Laboratory searches for dark matter with a 9-kg array of cryogenic germanium detectors. Symmetric sensors on opposite sides measure both charge and phonons from each particle interaction, providing excellent discrimination between electron nuclear recoils, surface interior events. Surface event rejection capabilities were tested two 210Pb sources producing ∼130 beta decays/hr. In ∼800 live hours, no events leaked into 8–115 keV signal...
The CUPID-Mo experiment, located at the Laboratoire Souterrain de Modane (France), was a demonstrator experiment for CUPID. It consisted of an array 20Li2Mo100O4 (LMO) calorimeters, each equipped with Ge light detector particle identification. In this work, we present result search two-neutrino and neutrinoless double-β decays Mo100 to first 0+ 2+ excited states Ru100 using full exposure (2.71kgyr LMO). We measure half-life 2νββ decay 01+ state as...
CUPID is a proposed future tonne-scale bolometric neutrinoless double beta decay ($0νββ$) experiment to probe the Majorana nature of neutrinos and discover Lepton Number Violation in so-called inverted hierarchy region neutrino mass. will be built on experience, expertise lessons learned CUORE, exploit current CUORE infrastructure as much possible. In order achieve its ambitious science goals, aims dramatically reduce backgrounds interest introducing high efficiently $α$/$β$ discrimination...
While the standard model of particle physics does not include free particles with fractional charge, experimental searches have ruled out their existence. We report results from Cryogenic Dark Matter Search (CDMS II) experiment that give first direct-detection limits for cosmogenically produced relativistic electric charge lower than e/6. A search tracks in six stacked detectors each two CDMS II towers finds no candidates, thereby excluding new parameter space charges between e/6 and e/200.
CUPID-Mo, located in the Laboratoire Souterrain de Modane (France), was a demonstrator for next generation $0\nu\beta\beta$ decay experiment, CUPID. It consisted of an array 20 enriched Li$_{2}$$ ^{100}$MoO$_4$ bolometers and Ge light detectors has demonstrated that technology scintillating with particle identification capabilities is mature. Furthermore, CUPID-Mo can inform validate background prediction In this paper, we present detailed model backgrounds. This able to describe well...