Energetic Superflare from a Young Solar Analog, DS Tucanae A, Observed with NICER

Abstract

Superflares in young solar analogs serve as proxies to the environment that shaped Earth into a habitable planet. DS Tucanae A is a young (45 Myr) solar analog producing superflares detectable in the X-ray energies and other bands. We detect and characterize a superflare using NICER. We model the peak emission of the superflare and find a temperature of 3.8 ± 0.3 keV, or (43.9 ± 3.5) × 106 K, and emission measure of (1.11 ± 0.03) × 1054 cm−3. We fit the flux values over time to a fast rise, exponential decay model, and find the decay timescale of the flare is τ = (4.9 ± 0.5) × 103 s. The total X-ray energy of the superflare is (2.8 ± 0.1) × 1035 erg. We estimate the loop length L = (6.3 ± 1.0) × 1010 cm2 and coronal magnetic field strength B c = 152 ± 22 G.