Simultaneous Multiwavelength Observations of the Highly Active M Dwarf YZ CMi

Date

2021-07-23

Type of Work

Department

Program

Citation of Original Publication

Rights

This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.
Public Domain Mark 1.0

Subjects

Abstract

The highly active M dwarf star, YZ CMi, was simultaneously observed by the Transiting Exoplanet Survey Satellite (TESS), the Neil Gehrels Swift Observatory (Swift), and the Very Large Array (VLA) in 2019 January. An extreme flaring event (>24 minutes, ~7.6x10³¹ erg) occurred on 2019 January 25 that was detected by all three observatories. TESS re-observed YZ CMi in 2021 January, this time at 20-second cadence, which allowed the detection of smaller flares and better resolved flare morphology in white light as compared to the 2-minute data collection mode. We compare flare rates between both TESS observation periods and analyze the spot evolution in TESS Sectors 7 and 34, due to changes in brightness variability activity from the two different TESS sectors. Simultaneous observations were also taken with Swift, the Neutron Interior Composition Explorer (NICER), and the CTIO/SMARTS 0.9-m during Sector 34. We analyze the energy partition of flares and compare the flare frequency distribution (FFDs) of events observed simultaneously by the different observatories