1,113 research outputs found
The ATLAS Search for Supersymmetry and its Connection to Dark Matter
This talk discusses how a Supersymmetry (SUSY) discovery at the LHC could improve our understanding of Dark Matter. We present a selection of recent and older ATLAS studies that show how a combination of LHC measurements can be used to constrain the SUSY model, which in favorable models may allow us to calculate the mass, nuclear interaction cross-section, and relic density of the lightest SUSY particle (LSP). Comparing these quantities with results from Dark Matter direct-detection experiments, and with results from Observational Cosmology, would enable us to establish the role of the SUSY LSP in the Dark Matter within the next decade
Charge-Focusing Readout of Time Projection Chambers
Time projection chambers (TPCs) have found a wide range of applications in
particle physics, nuclear physics, and homeland security. For TPCs with
high-resolution readout, the readout electronics often dominate the price of
the final detector. We have developed a novel method which could be used to
build large-scale detectors while limiting the necessary readout area. By
focusing the drift charge with static electric fields, we would allow a small
area of electronics to be sensitive to particle detection for a much larger
detector volume. The resulting cost reduction could be important in areas of
research which demand large-scale detectors, including dark matter searches and
detection of special nuclear material. We present simulations made using the
software package Garfield of a focusing structure to be used with a prototype
TPC with pixel readout. This design should enable significant focusing while
retaining directional sensitivity to incoming particles. We also present first
experimental results and compare them with simulation.Comment: 5 pages, 17 figures, Presented at IEEE Nuclear Science Symposium 201
Probing neutralino dark matter in the MSSM & the NMSSM with directional detection
We investigate the capability of directional detectors to probe neutralino
dark matter in the Minimal Supersymmetric Standard Model and the
Next-to-Minimal Supersymmetric Standard Model with parameters defined at the
weak scale. We show that directional detectors such as the future MIMAC
detector will probe spin dependent dark matter scattering on nucleons that are
beyond the reach of current spin independent detectors. The complementarity
between indirect searches, in particular using gamma rays from dwarf spheroidal
galaxies, spin dependent and spin independent direct search techniques is
emphasized. We comment on the impact of the negative results on squark searches
at the LHC. Finally, we investigate how the fundamental parameters of the
models can be constrained in the event of a dark matter signal.Comment: 21 pages, 16 figure
Machine Learning for New Physics Searches in B â K*0”+”â Decays
We report the status of a neural network regression model trained to extract new physics (NP) parameters in Monte Carlo (MC) simulation data. We utilize a new EvtGen NP MC generator to generate B â K*0”+”â events according to the deviation of the Wilson Coefficient C9 from its SM value, ÎŽC9. We train a three-dimensional ResNet regression model, using images built from the angular observables and the invariant mass of the di-muon system, to extract values of ÎŽ
C9 directly from the MC data samples. This work is intended for future analyses at the Belle II experiment but may also find applicability at other experiments
CYGNUS
Directional information in the direct dark matter searches is believed to be able providing a clear discovery of the galactic WIMP dark matter, together with a further potential to investigate the properties of the dark matter. CYGNUS is a concept to detect the galactic WIMP dark matter particles with directionality. In this paper, physics motivation and technological R&D status will be reviewedThis work was supported by the Japanese Ministry of Education, Culture, Sports, Science and Technology, Grant-in-Aid for Scientic Research, ICRR Joint-Usage, JSPS KAKENHI Grant Number, 16H02189, 19H05802, 19H05806, 26104001, 26104005, and JSPS Bilateral Collaborations (Joint Research Projects and Seminars) program. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 818744)
Measurement of the decay and determination of
We present a measurement of the charmless semileptonic decay
using a data sample containing 657
events collected with the Belle detector at the KEKB
asymmetric-energy collider operating near the
resonance. We determine the total branching fraction of the decay,
. We also report a new precise measurement
of the differential decay rate, and extract the Cabibbo-Kobayashi-Maskawa
matrix element using model-independent and -dependent approaches.
From a simultaneous fit to the measured differential decay rate and lattice QCD
results, we obtain , where the error
includes both statistical and systematic uncertainties.Comment: 8 pages, 3 figures, Submitted to PRD(RC
Observation of the decay B^0->D+D*-
We report the first observation of the decay B^0->D+-D*-+ with the Belle
detector at the KEKB e^+e^- collider operated at the Upsilon(4S) resonance. The
sum of branching fractions B(B^0->D+D*-)+B(B^0->D-D*+) is measured to be
(1.17+-0.26+0.22-0.25)x10^-3 using the full reconstruction method where both
charmed mesons from B^0 decays are reconstructed. A consistent value
((1.48+-0.38+0.28-0.31)x10^-3) is obtained using a partial reconstruction
technique that only uses the slow pion from the D*- ->bar D^0pi- decay and a
fully reconstructed D+ to reconstruct the B^0.Comment: 10 pages, 3 figure
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