A5046019162- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Cosmology and Gravitation Theories
- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Atomic and Subatomic Physics Research
- Gaussian Processes and Bayesian Inference
- Galaxies: Formation, Evolution, Phenomena
- Statistical Mechanics and Entropy
- CCD and CMOS Imaging Sensors
- Statistical and numerical algorithms
- High-Energy Particle Collisions Research
- Functional Brain Connectivity Studies
- Advanced Mathematical Theories and Applications
- Solar and Space Plasma Dynamics
- Pulsars and Gravitational Waves Research
- Radioactive Decay and Measurement Techniques
- Gamma-ray bursts and supernovae
- Scientific Research and Discoveries
King's College London
2016-2018
Institut d'Astrophysique de Paris
2015-2016
Sorbonne Université
2016
Centre National de la Recherche Scientifique
2016
Durham University
2012-2015
University of Sheffield
2006
Texas A&M University
2005
The DAMA/LIBRA experiment searches for evidence of dark matter scattering off nuclei. Data from DAMA show 9.2σ an annual modulation, consistent with having a cross section around 2×10−40 cm2. However, this is excluded by other direct detection experiments. We propose alternative source modulation in the form neutrons, which have been liberated material surrounding detector combination B8 solar neutrinos and atmospheric muons. phase muon lags 30 days behind data; however, we that adding...
Using data from the $\ensuremath{\nu}$-cleus detector, based on surface of Earth, we place constraints dark matter in form strongly interacting massive particles (SIMPs) which interact with nucleons via nuclear-scale cross sections. For large SIMP-nucleon sections, sensitivity traditional direct searches using underground experiments is limited by energy loss experienced SIMPs, due to scattering rock overburden and experimental shielding their way detector apparatus. Hence, a surface-based...
We perform an independent analysis of data from the CoGeNT direct detection experiment to quantify evidence for dark matter recoils. critically re-examine assumptions that enter analysis, focusing specifically on separation bulk and surface events, latter which constitute a large background. This is performed using event rise-time, with events being slower average. fit rise-time distributions log-normal Pareto distribution (which gives better tail in population at high rise-times) account...
We investigate the robustness of resonance like feature centred at around a 750 GeV invariant mass in 13 TeV diphoton data, recently released by ATLAS collaboration. focus on choice empirical function used to model continuum background order quantify uncertainties analysis due this choice. extend chosen collaboration one with two components. By performing profile likelihood we find that local significance drops from $3.9σ$ using function, and freely-varying width, only $2σ$ our own function....
We review the status and future of direct searches for light dark matter. start by answering question: `Whatever happened to matter anomalies?' i.e. fate potential signals observed CoGeNT, CRESST-II, CDMS-Si DAMA/LIBRA experiments. discuss how excess events in first two these experiments have been explained previously underestimated backgrounds. For DAMA we summarise progress mundane explanations annual modulation reported its event rate. Concerning detection focus on irreducible background...
Future multi-tonne Direct Detection experiments will be sensitive to solar neutrino induced nuclear recoils which form an irreducible background light Dark Matter searches. Indeed for masses around 6 GeV the spectra of neutrinos and are so similar that said run into a floor, sensitivity increases only marginally with exposure past certain cross section. In this work we show floor can overcome using different annual modulation expected from Matter. Specifically sections below DM signal is...
Several next-generation experiments aim to make the first measurement of neutrino flux from Carbon-Nitrogen-Oxygen (CNO) solar fusion cycle. We calculate how much time these will need run for in order measure this with enough precision tell us metal content Sun's core, and thereby help solve metallicity problem. For looking at neutrino-electron scattering, we find that SNO+ CNO after five years its pure scintillator mode, provided 210Bi background is measured 1% accuracy. By comparison, a...
We study the effects on spectrum and distribution of high-energy neutrinos due to scattering with dark matter both outside within our galaxy, focusing observed by IceCube experiment energies up several PeV. If these originate from extra-galactic astrophysical sources, then in transit particles will delay their arrival Earth. This results a cut-off at an energy set cross section, allowing us place upper limit sections $\sigma$ which increase E level < 10^{-17} x (m / GeV) (E PeV)^2 cm^2, for...
In 2011, the XENON100 experiment has set unprecedented constraints on dark matter-nucleon interactions, excluding matter candidates with masses down to 6 GeV if corresponding cross section is larger than 10^{-39} cm^2. The dependence of exclusion limit in terms scintillation efficiency (Leff) been debated at length. To overcome possible criticisms performed an analysis which Leff was considered as a nuisance parameter and its uncertainties were profiled out by using Gaussian likelihood mean...
Future neutrino detectors will obtain high-statistics data from a nearby core-collapse supernova. We study the mixing with eV-mass sterile neutrinos in supernova environment and its effects on active fluxes as detected by Hyper-Kamiokande IceCube. Using Markov Chain Monte Carlo analysis, we make projections for how accurately these experiments measure active-sterile angle θs given that there are substantial uncertainties expected luminosity spectrum of galactic burst. find can reconstruct...
The experimental situation of dark matter direct detection has reached an exciting crossroads, with potential hints a discovery (DM) from the CDMS, CoGeNT, CRESST-II and DAMA experiments in tension null results xenon-based such as XENON100 LUX. Given present controversial status, it is important that analytical method used to search for DM both robust flexible enough deal data which distinction between signal background points difficult, hence where choice setting limit or defining region...
We quantify the amount of data needed in order to measure size and position $^{8}\mathrm{B}$ neutrino production region within solar core, for experiments looking at elastic scattering between electrons neutrinos. The directions immediately after are strongly correlated with incident neutrinos; however, this is degraded significantly by subsequent these detector medium. generate distributions such different profiles, use a maximum likelihood analysis make projections future experimental...
Resonant interactions between neutrinos from a Galactic supernova and dark matter particles can lead to sharp dip in the neutrino energy spectrum. Due its excellent resolution, measurement of this effect with JUNO experiment provide evidence for such couplings. We discuss how may confirm or further constrain model where scalar couples active another fermion.
We consider the observation of diffuse halos light around discs spiral galaxies, as a probe interaction cross section between Dark Matter and photons. Using galaxy M101 an example, we show that for scattering at level 10^(-23) x (m/GeV) cm^2 or greater in halo will scatter out from more luminous centre disc to larger radii, contributing effective increased surface brightness edges observed area on sky. This allows us set upper limit DM-photon using data Dragonfly instrument. then how improve...
A supernova event in our own galaxy will result a large number of neutrinos detected on Earth within the time-frame few seconds. These have been produced thermally with, principle, three distinct temperatures for electron, anti-electron and remaining heavy flavours respectively. We revisit possibility that new MeV-mass particles $χ$ are also during event, which scatter with alter their temperatures. Our main emphasis is detectability this effect using neutrino spectrum, given uncertainty...
We make projections for measuring the black hole birth rate from diffuse supernova neutrino background (DSNB) by future experiments, and constrain merger fraction $\epsilon$, when combined with information on gravitational wave experiments such as LIGO. The DSNB originates neutrinos emitted all supernovae in Universe, is expected to be made up of two components: neutron-star-forming supernovae, a sub-dominant component at higher energies black-hole-forming "unnovae". perform Markov Chain...
We examine whether charged particles injected by self-annihilating dark matter (DM) into regions undergoing diffuse shock acceleration can be accelerated to high energies. consider three astrophysical sites where is supposed occur, namely the Galactic center and galaxy cluster mergers. For Milky Way, we find that of cosmic rays could lead a bump in ray spectrum provided product efficiency mechanism concentration DM enough. Within Galaxy, Fermi bubbles are potentially more efficient...
In this paper we propose to use the measurement of thermal Quark-Gluon Plasma (QGP) dilepton spectra in Intermediate Mass Region (IMR) heavy-ion collisions, as a new method search for GeV-scale dark gauge bosons (gamma' or Z'). Such light mediators are common feature (i.e. low mass) matter scenarios, which have been invoked explain puzzling signals indirect and direct detection experiments. First show that gamma' Z' will generate resonant enhancement spectrum produced thermally by QGP, at an...