# KICP postdocs symposium

3:30–4:30 pm ERC 161

Jose Maria Ezquiaga
"Gravitational lensing of gravitational waves: a pandemic love story"
Observing gravitational lensing of gravitational waves is around the corner thanks to the increase in the number of detections and their redshift range. In this talk I will summarize how we can identify GW lensing and what it will teach us about astrophysics, cosmology and fundamental physics.

Lucas Secco
"New results in cosmic shear during a global pandemic”
I'll talk about the research program that kept me busy during the pandemic year. Firstly, the recent cosmic shear cosmology results from DES Y3 have added an important piece to the puzzle of the S8 tension. In addition to that, and in the spirit of advancing the information content available to weak lensing cosmology, I have recently made some of the highest signal-to-noise detections of 3-point lensing to date and teamed up with Chicagoland astrophysicists to create an extra 5,000 sq.deg shear catalog with DECam data.”

Katie Harrington
"In-lab Optical Characterization of the Simons Observatory Large Aperture Telescope Optics Tubes"
The Simons Observatory is a next generation CMB experiment which will deploy four telescopes, one 5m Large Aperture Telescope (LAT) and three 0.5 m Small Aperture Telescopes (SATs) to the Chilean Atacama Desert. The LAT cryogenic receiver will initially contain seven optics tubes divided into three flavors: low (27/39 GHz), mid (93/145 GHz), and ultra-high (225/280 GHz) frequency. I will discuss the ongoing in-lab testing efforts at UChicago to measure and validate the optical performance of the LAT optics tubes to ensure they are able to meet the scientific goals of Simons Observatory.

Yu-Dai Tsai
"Asteroid & Planetary Tracking Array and Space Quantum Technologies for Fundamental Physics"
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 baryon-coupled scalar, we estimate the sensitivity reach for the fifth-force coupling strength and mediator mass in the mass range $m \simeq 10^{-21}-10^{-15}\,{\rm eV}$. Our estimated sensitivity is comparable to leading limits from torsion balance experiments, potentially exceeding these in a specific mass range. The fifth forced-induced precession increases with the orbital semi-major axis in the small $m$ limit, motivating the study of objects further away from the Sun. We discuss future exciting prospects for extending our study to more than a million asteroids (including NEOs, main-belt asteroids, Hildas, and Jupiter Trojans), as well as trans-Neptunian objects and exoplanets. Our work can also be applied to the studies of dark matter and, potentially, gravitational waves. The new development of NASA/NIST proposals of Quantum technologies in Space could bring improvements to our studies, which I will discuss briefly near the end of the talk. This talk is mainly based on https://arxiv.org/abs/2107.04038 <https://urldefense.com/v3/__https://arxiv.org/abs/2107.04038__;!!BpyFHLRN4TMTrA!tQGeU8aTm9YuJZAawHaFP5K7MmkOcCtsGDhdNqpLuTmUX1LIVTUPPUB1U-HSxJWfsp0T7s0\$> .

Talks

Oct 6