Characterisation of the NUV and Optical Emission and Temperature of Flares from Ross 733 with Swift and TESS

Abstract

We present the results of a coordinated campaign to simultaneously observe the M star binary Ross 733 simultaneously in the optical and near-ultraviolet (NUV) with TESS and Swift respectively. We observed two flares in the Swift NUV light curve. One of these was decay phase of a flare that was also detected with TESS and the other was only detected in the NUV. We used the TESS light curve to measure the white-light flare rate of Ross 733, and calculate that the system flares with an energy of $10^{33}$ erg once every 1.5 days. We used our simultaneous observations to measure a pseudo-continuum temperature of $7340_{-900}^{+810}$K during the flare decay. We also used our observations to test the NUV predictions of the 9000 K blackbody flare model, and find that it underestimates number of flares we detect in our Swift NUV light curve. We discuss the reasons for this and attribute it to the unaccounted contributions from emission lines and continuum temperatures above 9000 K. We discuss how additional observations are required to break the degeneracy between the two in future multi-wavelength flare campaigns.

arXiv comment6 Pages, 3 figures, Accepted for publication in the Monthly Notices of the Royal Astronomical Society

References in corpus (35)

• emcee: The MCMC Hammer
• Gaia Data Release 2: The astrometric solution
• Estimating distances from parallaxes IV: Distances to 1.33 billion stars in Gaia Data Release 2
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• Superflares on Solar Type Stars Observed with Kepler I. Statistical Properties of Superflares
• APOGEE Data and Spectral Analysis from SDSS Data Release 16: Seven Years of Observations Including First Results from APOGEE-South
• Kepler Flares I. Active and Inactive M dwarfs
• Kepler Flares II: The Temporal Morphology of White-Light Flares on GJ 1243
• The Next Generation Transit Survey (NGTS)
• Time-Resolved Properties and Global Trends in dMe Flares from Simultaneous Photometry and Spectra
• Identifying the young low-mass stars within 25 pc. II. Distances, kinematics and group membership
• The Origin of RNA Precursors on Exoplanets
• Connecting Flares and Transient Mass Loss Events in Magnetically Active Stars
• Flare Statistics for Young Stars from a Convolutional Neural Network Analysis of $\text{TESS}$ Data
• The flare catalog and the flare activity in the Kepler mission
• Radiative Hydrodynamic Models of Optical and Ultraviolet Emission from M Dwarf Flares
• Optical, UV, and X-Ray Evidence for a 7-Year Stellar Cycle in Proxima Centauri
• Magnetic Inhibition of Convection and the Fundamental Properties of Low-Mass Stars. II. Fully Convective Main Sequence Stars
• HAZMAT. IV. Flares and Superflares on Young M Stars in the Far Ultraviolet
• Propagation of Alfvénic Waves From Corona to Chromosphere and Consequences for Solar Flares
• EvryFlare III: Temperature Evolution and Habitability Impacts of Dozens of Superflares Observed Simultaneously by Evryscope and TESS
• A Very Bright, Very Hot, and Very Long Flaring Event from the M Dwarf Binary System DG CVn
• gPhoton: The GALEX Photon Data Archive
• The Near-Ultraviolet Continuum Radiation in the Impulsive Phase of HF/GF-Type dMe Flares I: Data
• GALEX Observations of an Energetic Ultraviolet Flare on the dM4e Star GJ 3685A
• Stellar flares detected with the Next Generation Transit Survey
• A Relationship Between Stellar Age and Spot Coverage
• Short Duration Stellar Flares in GALEX Data
• Near-Ultraviolet Spectra of Flares on YZ CMi
• Parameterizations of Chromospheric Condensations in dG and dMe Model Flare Atmospheres
• The effect of starspots on the ages of low-mass stars determined from the lithium depletion boundary
• Characteristics that Produce White-Light Enhancements in Solar Flares Observed by Hinode/SOT
• Spectroscopic orbits of nearby stars
• Stellar flares from blended and neighbouring stars in Kepler short cadence observations
• Characterization of M dwarfs Using Optical Mid-Resolution Spectra for Exploration of Small Exoplanets

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