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

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 B0→π−ℓ+νB^0\to\pi^-\ell^+\nu and determination of ∣Vub∣|V_{ub}|

We present a measurement of the charmless semileptonic decay $B^0\to\pi^-\ell^+\nu$ using a data sample containing 657$\times 10^6$ $B\bar{B}$ events collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider operating near the $\Upsilon(4S)$ resonance. We determine the total branching fraction of the decay, $\mathcal{B}(B^0\to\pi^-\ell^+\nu)=(1.49\pm 0.04{(\mathrm{stat})}\pm 0.07{(\mathrm{syst})})\times 10^{-4}$. We also report a new precise measurement of the differential decay rate, and extract the Cabibbo-Kobayashi-Maskawa matrix element $|V_{ub}|$ using model-independent and -dependent approaches. From a simultaneous fit to the measured differential decay rate and lattice QCD results, we obtain $|V_{ub}|=(3.43\pm 0.33)\times 10^{-3}$, 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

Observation of Bs0→J/ψf0(980)B_s^0\to J/\psi f_0(980) and Evidence for Bs0→J/ψf0(1370)B_s^0\to J/\psi f_0(1370)

We report the first observation of $B_s^0\to J/\psi f_0(980)$ and first evidence for $B_s^0\to J/\psi f_0(1370)$, which are CP eigenstate decay modes. These results are obtained from $121.4\;\mathrm{fb}^{-1}$ of data collected at the $\Upsilon(5S)$ resonance with the Belle detector at the KEKB $e^+e^-$ collider. We measure the branching fractions $\mathcal{B}(B_s^0\to J/\psi f_0(980);f_0(980)\to\pi^+\pi^-)=(1.16^{+0.31}_{-0.19}(\mathrm{stat.})^{+0.15}_{-0.17}(\mathrm{syst.})^{+0.26}_{-0.18}(N_{B_s^{(*)}\bar B_s^{(*)}})) \times 10^{-4}$ with a significance of $8.4\sigma$, and $\mathcal{B}(B_s^0\to J/\psi f_0(1370);f_0(1370)\to\pi^+\pi^-)=(0.34^{+0.11}_{-0.14}(\mathrm{stat.})^{+0.03}_{-0.02}(\mathrm{syst.})^{+0.08}_{-0.05}(N_{B_s^{(*)}\bar B_s^{(*)}})) \times 10^{-4}$ with a significance of $4.2\sigma$. The last error listed is due to uncertainty in the number of produced $B_s^{(*)}\bar B_s^{(*)}$ pairs.Comment: 5 pages, 2 figures, 2 tables, published in PR