A5020807279- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Cosmology and Gravitation Theories
- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Atomic and Subatomic Physics Research
- Stellar, planetary, and galactic studies
- Quantum Chromodynamics and Particle Interactions
- Solar and Space Plasma Dynamics
- Black Holes and Theoretical Physics
- Astro and Planetary Science
- Physics of Superconductivity and Magnetism
- Geophysics and Gravity Measurements
- Cold Atom Physics and Bose-Einstein Condensates
- Gamma-ray bursts and supernovae
- Noncommutative and Quantum Gravity Theories
- Galaxies: Formation, Evolution, Phenomena
- Quantum and electron transport phenomena
- Particle Detector Development and Performance
- High-Energy Particle Collisions Research
- History and Developments in Astronomy
- Astrophysics and Star Formation Studies
- Pulsars and Gravitational Waves Research
- Fluoride Effects and Removal
- Topological Materials and Phenomena
Seoul National University
2023-2025
Government Medical College and Hospital
2025
University of Westminster
2025
Saha Institute of Nuclear Physics
2025
Homi Bhabha National Institute
2025
SLAC National Accelerator Laboratory
2014-2024
Stanford University
2014-2024
Menlo School
2021-2024
Kavli Institute for Particle Astrophysics and Cosmology
2024
Indian Association for the Cultivation of Science
2022
Flavor-universal neutrino self-interaction has been shown to ease the tension between values of Hubble constant measured from early and late Universe data. We introduce a structure that is flavor-specific in three active framework. This motivated by stringent constraints on new secret interactions among electron muon neutrinos several laboratory experiments. Our study indicates presence strongly interaction mode which implies late-decoupling just prior matter radiation equality. Using...
We point out that power measurements of single quasiparticle devices open a new avenue to detect dark matter (DM). The threshold these is set by the Cooper pair binding energy, and therefore so low they can DM as light about an MeV incoming from Galactic halo, well low-velocity thermalized component potentially present in Earth. Using existing with devices, SuperCDMS-CPD, we constraints on spin-independent scattering cross section for masses 10 GeV. outline future directions improve...
The XENON collaboration recently reported an excess of electron recoil events in the low energy region with a significance around $3.3\ensuremath{\sigma}$. An explanation this terms thermal dark matter seems challenging. We propose scenario where Milky Way halo gets boosted as result scattering diffuse supernova neutrino background. This interaction can accelerate dark-matter to semi-relativistic velocities, and flux, turn, scatter electrons detector, thereby providing much better fit data....
Abstract Diffuse neutrinos from past supernovae in the Universe present us with a unique opportunity to test dark matter (DM) interactions. These can scatter and boost DM particles Milky Way halo relativistic energies allowing detect them terrestrial laboratories. Focusing on generic models of DM-neutrino electron interactions, mediated by vector or scalar boson, we implement energy-dependent scattering cross-sections perform detailed numerical analysis attenuation due in-medium while...
Neutrino self-interactions are known to lead non-linear collective flavor oscillations in a core-collapse supernova. We point out new possible effects of non-standard (NSSI) neutrinos on conversions two-flavor framework. show that, for single-energy neutrino-antineutrino ensemble, instability is generated even normal hierarchy large enough NSSI. Using toy model the neutrino spectra, we that flavor-preserving NSSI pinching spectral swaps, while flavor-violating cause swaps develop away from...
Background The digitalisation of healthcare has provided new ways to address disparities in sexual health outcomes that particularly affect ethnic and minorities. Conversational artificial intelligence (AI) chatbots can provide personalised education refer users for appropriate medical consultations. We aimed explore design principles a chatbot-assisted culturally sensitive self-assessment intervention based on the disclosure health-related information. Methods In 2022, an online survey was...
A BSTRACT Context: Patient satisfaction is a crucial indicator of service quality in the healthcare system. There limited information regarding level sexual minority groups people living with HIV (PLHIV) treatment services. Aims: This comparative study assessed client among general (male and female) patients group antiretroviral delivery at ART center. Settings Design: cross-sectional analytical mixed-method approach was conducted from September 2023 to May 2024 center Barasat Government...
James Webb Space Telescope (JWST) has opened up a new chapter in infrared astronomy. Besides the discovery and deeper understanding of various astrophysical sources, JWST can also uncover non-gravitational nature dark matter (DM). If DM is QCD axion or an eV-scale Axion-like particle (ALP), it decay into two photons band. This will produce distinct line signature spectroscopic observations made by JWST. Using latest NIRSpec IFU from JWST, we put strongest bound on photon coupling for axion/...
We investigate phase transitions and critical phenomena of four dimensional dyonic charged AdS black holes in the framework thermodynamic geometry. In a mixed canonical–grand canonical ensemble with fixed electric charge varying magnetic these exhibit liquid–gas like first order transition culminating second point similar to van der Waals gas. show that scalar curvature R for follow our proposed geometrical characterization R-crossing Method exhibits divergence at point. The pattern crossing...
We report a measurement of $CP$ violating asymmetries in ${B}^{0}({\overline{B}}^{0})\ensuremath{\rightarrow}{K}^{+}{K}^{\ensuremath{-}}{K}_{S}^{0}$ decays with time-dependent Dalitz approach. This analysis is based on data sample $657\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs accumulated at the $\ensuremath{\Upsilon}(4S)$ resonance Belle detector KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. As result an unbinned maximum likelihood fit to selected...
Abstract We present an analysis of multiwavelength observations area 0.°27 × around the Galactic H ii region G18.88−0.49, which is powered by O-type star (age ∼ 10 5 yr). The Herschel column density map reveals a shell-like feature extension ∼12 pc 7 and mass ∼2.9 4 M ⊙ region; its existence further confirmed distribution molecular ( 12 CO, 13 C 18 O, NH 3 ) gas at [60, 70] km s −1 . Four subregions are studied toward this show range ∼0.8–10.5 These associated with dense dominated nonthermal...
Abstract We revisit the cosmology of neutrino self-interaction and use latest cosmic microwave background data from Atacama Cosmology Telescope (ACT) Planck experiment to constrain interaction strength. In both flavor-universal nonuniversal coupling scenarios, we find that ACT prefers strong delays free streaming until just before matter-radiation equality. When combined with 2018 data, preference for decreases due polarization data. For dataset, flavor-specific still provides a better fit...
We present the partial branching fraction for inclusive charmless semileptonic $B$ decays and corresponding value of Cabibbo-Kobayashi-Maskawa matrix element $|{V}_{ub}|$, using a multivariate analysis method to access $\ensuremath{\sim}90%$ $B\ensuremath{\rightarrow}{X}_{u}\ensuremath{\ell}\ensuremath{\nu}$ phase space. This approach dramatically reduces theoretical uncertainties from $b$-quark mass nonperturbative QCD compared all previous measurements. The results are based on sample...
Neutrinos might interact among themselves through forces that have so far remained hidden. Throughout the history of Universe, such secret interactions could lead to scatterings between neutrinos from supernova explosions and nonrelativistic relic left over big bang. Such can boost cosmic neutrino background ($\mathrm{C}\ensuremath{\nu}\mathrm{B}$) energies $\mathcal{O}(\mathrm{MeV})$, making it, in principle, observable experiments searching for diffuse background. Assuming a...
A bstract We recently pointed out that power measurements of single quasiparticle devices can be used to detect dark matter. These have the lowest known energy thresholds, far surpassing standard direct detection experiments, requiring deposition above only about an meV. calculate matter induced densities in transmon qubits, and use latest qubit provide one strongest existing lab-based bounds on matter-nucleon scattering below 100 MeV. strongly constrain sub-component matter, using both a...
We report the observation of two narrow structures at 10610MeV/c^2 and 10650MeV/c^2 in pi^{\pm}Upsilon(nS) (n=1,2,3) pi^{\pm}h_b(mP) (m=1,2) mass spectra that are produced association with a single charged pion Upsilon(5S) decays. The measured masses widths averaged over five final states M_1=10608.4\pm2.0MeV/c^2, Gamma_1=15.6\pm2.5MeV M_2=10653.2\pm1.5MeV/c^2, Gamma_2=14.4\pm3.2MeV. Analysis favors quantum numbers I^G(J^P)=1^+(1^+) for both states. results obtained 121.4fb^{-1} data sample...
We point out a selection rule for enhancement (suppression) of odd (even) partial waves dark matter coannihilation or annihilation using the Sommerfeld effect. Using this, usually velocity-suppressed $p$-wave can dominate signals in present Universe. The mechanism is manifestation exchange symmetry identical incoming particles, and generic multistate DM with off-diagonal long-range interactions. As consequence, relic late-time rates are parametrically different distinctive phenomenology,...
Macroscopic dark matter is almost unconstrained over a wide "asteroid-like" mass range, where it could scatter on baryonic with geometric cross section. We show that when such an object travels through star, produces shock waves which reach the stellar surface, leading to distinctive transient optical, UV and X-ray emission. This signature can be searched for variety of types locations. In dense globular cluster, events occur far more often than flare backgrounds, existing telescope probe...
Dark matter may have been relativistic and collisional until relatively late times become cold collisionless after a phase transition before the matter-radiation equality of standard ΛCDM cosmology. We show that such dark has large peculiar velocities due to acoustic oscillations transition, evolves ballistically in initial are redshifted away. this Ballistic Matter (BDM) results new non-trivial interesting features cosmological observables. In particular, linear power spectrum exhibits on...
Self-interaction among the neutrinos in early Universe has been proposed as a solution to Hubble tension, discrepancy between measured values of constant from CMB and low-redshift data. However, flavor-universal neutrino self-interaction is highly constrained by Big Bang Nucleosynthesis other laboratory experiments such as, tau K-meson decay, double-neutrino beta decay etc. We study cosmology when only one or two states are self-interacting. Such flavor-specific interactions less...
Multi-level dark matter with diagonal and off-diagonal interactions shows a rich phenomenology in its self-scattering. If the are mediated by particle that is less massive than matter, Sommerfeld effect can lead to resonant enhancement of scattering. For mediators lighter level separation, particles upscatter excited states de-excite emitting these mediators. We compute cross-sections, both above below kinematic threshold, generic two-component model identify large inelastic cross-section as...
The light dark matter mass regime has emerged as the next frontier in direct detection experiment due to lack of any signal higher range. In this paper, we propose a new detector material, bilayer stack graphene detect sub-MeV matter. Its voltage-tunable low energy sub-eV electronic band gap makes it an excellent choice for material search experiment. We compute its dielectric function using random phase approximation and estimate projected sensitivity matter-electron scattering absorption....