J 2016

A VERY BRIGHT, VERY HOT, AND VERY LONG FLARING EVENT FROM THE M DWARF BINARY SYSTEM DG CVn

OSTEN, Rachel A., Adam KOWALSKI, Stephen A. DRAKE, Hans KRIMM, Kim PAGE et. al.

Základní údaje

Originální název

A VERY BRIGHT, VERY HOT, AND VERY LONG FLARING EVENT FROM THE M DWARF BINARY SYSTEM DG CVn

Autoři

OSTEN, Rachel A. (840 Spojené státy), Adam KOWALSKI (840 Spojené státy), Stephen A. DRAKE (840 Spojené státy), Hans KRIMM (840 Spojené státy), Kim PAGE (826 Velká Británie a Severní Irsko), Kosmas GAZEAS (300 Řecko), Jamie KENNEA (840 Spojené státy), Samantha OATES (724 Španělsko), Mathew PAGE (826 Velká Británie a Severní Irsko), Enrique DE MIGUEL (724 Španělsko), Rudolf NOVÁK (203 Česká republika, garant, domácí), Tomáš APELTAUER (203 Česká republika) a Neil GEHRELS (840 Spojené státy)

Vydání

Astrophysical Journal, BRISTOL, IOS Publishing, 2016, 0004-637X

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Velká Británie a Severní Irsko

Utajení

není předmětem státního či obchodního tajemství

Odkazy

Impakt faktor

Impact factor: 5.533

Kód RIV

RIV/00216224:14310/16:00093551

Organizační jednotka

Přírodovědecká fakulta

UT WoS

000390490100034

Klíčová slova anglicky

stars: coronae; stars: flare; stars: individual (DG CVn)

Štítky

Příznaky

Mezinárodní význam, Recenzováno
Změněno: 29. 3. 2017 16:24, Ing. Andrea Mikešková

Anotace

V originále

On 2014 April 23, the Swift satellite responded to a hard X-ray transient detected by its Burst Alert Telescope, which turned out to be a stellar flare from a nearby, young M dwarf binary DG CVn. We utilize observations at X-ray, UV, optical, and radio wavelengths to infer the properties of two large flares. The X-ray spectrum of the primary outburst can be described over the 0.3-100 keV bandpass by either a single very high-temperature plasma or a nonthermal thick-target bremsstrahlung model, and we rule out the nonthermal model based on energetic grounds. The temperatures were the highest seen spectroscopically in a stellar flare, at T-X of 290 MK. The first event was followed by a comparably energetic event almost a day later. We constrain the photospheric area involved in each of the two flares to be >10(20) cm(2), and find evidence from flux ratios in the second event of contributions to the white light flare emission in addition to the usual hot, T similar to 10(4) K blackbody emission seen in the impulsive phase of flares. The radiated energy in X-rays and white light reveal these events to be the two most energetic X-ray flares observed from an M dwarf, with X-ray radiated energies in the 0.3-10 keV bandpass of 4 x 10(35) and 9 x 10(35) erg, and optical flare energies at E-V of 2.8 x 10(34) and 5.2 x 10(34) erg, respectively. The results presented here should be integrated into updated modeling of the astrophysical impact of large stellar flares on close-in exoplanetary atmospheres.