Pulsars - spinning neutron stars that are magnetized – are possible candidates that could explain the large excess in the observed positron fraction - ratio of positrons to electrons plus positrons present in data measurements from the AMS-01, HEAT, and PAMELA collaborations. While these results are in great tension with predictions of secondary productions of cosmic rays in the interstellar...
We study for the first time the possibility of probing long-range fifth forces utilizing asteroid astrometric data, via the fifth force-induced orbital precession. We examine nine Near-Earth Object (NEO) asteroids whose orbital trajectories are accurately determined via optical and radar astrometry. Focusing on a Yukawa-type potential mediated by a new gauge field (dark photon) or a...
In this work, we use variational autoencoders to build a surrogate for the model spectra of optical counterparts to neutron star containing gravitational wave events. Optical counterparts to gravitational wave events reveal information that is not necessarily included in the gravitational wave signal. Modeling of these radioactively-powered time-domain transients, kilonovae, is computationally...
Leveraging large samples of galaxy mergers from future large-scale surveys will be crucial for furthering our understanding of galaxy evolution and the formation of matter in the universe. Using machine learning models trained on simulated images of merging galaxies and then applying them to newly observed data will help tremendously with these efforts. Unfortunately, training a neural network...
In this talk I will give a brief overview of the Scientific Computing Division (SCD), with the emphasis on the Artificial Intelligence (AI) Projects and work done in this area. Finally, I will briefly talk about my position and work as part of the SCD. My background is in astrophysics and I currently work on several projects leveraging AI as a tool for scientific discovery. I am interested in...
The $\Lambda$CDM model provides an excellent fit to the CMB data. However, a statistically significant tension emerges when its determination of the Hubble constant $H_0$ is compared to the local distance-redshift measurements. The axi-Higgs model, which couples ultralight axions to the Higgs field, offers a specific variation of the $\Lambda$CDM model. It relaxes the $H_0$ tension as well as...
CMB-S4 and other next generation observatories for the cosmic microwave background (CMB) require high performance optical elements. Ideally, these optical elements need to provide a large aperture, have low losses, a high index of refraction, and operate at cryogenic temperatures. Alumina is a material that satisfies these requirements while also providing advantageous properties for filtering...
We present first results from our work on automated telescope scheduling with reinforcement learning techniques. With the increasing size of optical astronomical surveys, automated observation scheduling tools are becoming necessary for the operation of large space and ground based telescopes in an efficient manner. These scheduling methods need to have the capacity for rapid adjustment to...
It is well understood that the dark matter profile of clusters exhibits notable differences in linear and non-linear regimes. The halo model describes these dark matter profiles at both linear and nonlinear scales by incorporating the one-halo and two-halo terms in the model. However, recent measurements of the galaxy-splashback effect have indicated that the underlying model that assumes a...
In recent years, multimessenger astronomy has provided new oportunities to reveal the mysteries of cosmology and potentially resolve the tension in the Hubble Constant measurement. The Dark Energy Survey collaborates with LIGO through electromagnetic follow-up of LIGO-Virgo detections of gravitational wave events. For binary neutron star and perhaps neutron star-black hole mergers we expect to...
The Axion Dark Matter eXperiment (ADMX) is a haloscope search for the dark matter axion. The QCD axion, if discovered, solves both the strong CP problem in nuclear physics and the dark matter problem in cosmology. ADMX seeks to detect axions by their resonant conversion to microwave photons in a high Q cavity immersed in a strong magnetic field. Because the expected signal is of yocto-watt...
The constituents of dark matter are still unknown, and the viable possibilities span a very large mass range. Specific scenarios for the origin of dark matter sharpen the focus on a narrower range of masses: the natural scenario where dark matter originates from thermal contact with familiar matter in the early Universe requires the DM mass to lie within about an MeV to 100 TeV. Considerable...
The constituents of dark matter are still unknown, and the viable possibilities span a very large mass range. The Light Dark Matter eXperiment (LDMX) is a planned fixed-target experiment at SLAC that will probe a variety of dark matter models in the sub-GeV mass range using a missing momentum technique. A subset of rare photonuclear (PN) events can produce neutral hadrons that escape the...
If light dark matter gains enough kinetic energy from collision with cosmic rays, it could leave a detectable signal in a neutrino experiment detector. PROSPECT, the PRecision Oscillation and SPECTrum Experiment, is a reactor antineutrino experiment deployed on surface with minimal overburden (< 1 m.w.e). This configuration provides the opportunity to test hard-to-reach regions of dark matter...