BBL 5/17/2021 — Speakers: Caleb Canas (Penn State University) And Randall Rojas (University Of Utah)

Monday May 17, 2021 12:00 pm
via Zoom

Characterizing Jupiter-sized planets orbiting TESS M dwarfs
Caleb Canas, Penn State University

Abstract: More than two decades have passed since the discovery of Jupiter-sized planets (hot Jupiters and warm Jupiters, depending on their period) with close-in orbits of a few days. These planets have no Solar System analogue and have occurrence rates which fall off around the most numerous stars, the M dwarfs. The TESS mission is well suited to find M dwarfs hosting these types of planets. I will begin with a summary of ongoing observational efforts aimed at finding and characterizing Jupiter-sized transits around M dwarfs with TESS data. I will then discuss an intriguing set of low-density planet candidates which have emerged from our search. These are puffy planets that are large in radius (>7 R_earth) but with small masses (<100 M_earth) and are lucrative targets for atmospheric characterization missions as they represent a population of exoplanets that have not, as of yet, been detected around M dwarfs.

A Rarity in the Universe: MACSJ0717
Randall Rojas,
University of Utah

Abstract: The most energetic events in the Universe since the Big Bang have been the merging of 2 galaxy clusters. In rare cases, such as with MACSJ0717, 4 subclusters have been observed to be undergoing a merger. This produces a complex merger structure with very hot (T > 20 keV) gas, only observed in clusters containing shocks with high Mach number shocks (M > 2) such as the Bullet Cluster and Abell 665. While Chandra measurements have been performed on this cluster, the constraints placed on this hot gas are inconclusive. NuSTAR’s ability to probe into the hard X-ray band provides better constraints on this temperature, as well as an opportunity to constrain potential Inverse Compton (IC) scattering that may occur from the reacceleration of electrons by the shock front. In this talk, I will describe how we use NuSTAR to analyze this cluster and provide constraints on the hot temperature region of interest as well as use the IC flux limit to determine the lower limit of the magnetic field strength of the cluster.


Event Contact

Debbie Meinbresse