EDEN: Flare Activity of the Nearby Exoplanet-hosting M Dwarf Wolf 359 Based on K2 and EDEN Light Curves

被引：10

作者：

Lin, Chia-Lung ^{[1
]}

Chen, Wen-Ping ^{[1
]}

Ip, Wing-Huen ^{[1
,2
,3
]}

Apai, Daniel ^{[4
,5
]}

Bixel, Alex ^{[4
]}

Boyle, Richard ^{[6
]}

Chavez, Jose Perez ^{[4
]}

Espinoza, Nestor ^{[7
]}

Gibbs, Aidan ^{[8
]}

Gabor, Paul ^{[6
]}

Henning, Thomas ^{[9
]}

Mancini, Luigi ^{[9
,10
,11
]}

Rackham, Benjamin, V ^{[12
,13
]}

Schlecker, Martin ^{[9
]}

Dietrich, Jeremy ^{[4
]}

Socia, Quentin Jay ^{[4
]}

Keppler, Miriam ^{[9
]}

Bhandare, Asmita ^{[9
]}

Haeberle, Maximilian ^{[9
]}

机构：

[1] Natl Cent Univ, Grad Inst Astron, Taoyuan 32001, Taiwan

[2] Natl Cent Univ, Grad Inst Space Sci, Taoyuan 32001, Taiwan

[3] Macau Univ Sci & Technol, Space Sci Inst, Macau, Peoples R China

[4] Steward Observ, 933 N Cherry Ave, Tucson, AZ 85721 USA

[5] Lunar & Planetary Lab, 1629 E Univ Blvd, Tucson, AZ 85721 USA

[6] Univ Arizona, Vatican Observ Res Grp, 933 N Cherry Ave, Tucson, AZ 85721 USA

[7] Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA

[8] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA

[9] Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany

[10] Univ Roma Tor Vergata, Dept Phys, Via Ric Sci 1, I-00133 Rome, Italy

[11] INAF Turin Astrophys Observ, Via Osservatorio 20, I-10025 Pino Torinese, Italy

[12] MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA

[13] MIT, Kavli Inst Astrophys & Space Res, 77 Massachusetts Ave, Cambridge, MA 02139 USA

来源：

ASTRONOMICAL JOURNAL | 2021年 / 162卷 / 01期

关键词：

MULTIWAVELENGTH OBSERVATIONS; STELLAR FLARES; GIANT FLARE; CN LEONIS; STARS; MASS; SUPERFLARES; DISTRIBUTIONS; HABITABILITY; PHOTOMETRY;

D O I：

10.3847/1538-3881/abf933

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report the flare activity of Wolf 359, the fifth closest star to the Sun and a candidate exoplanet-hosting M dwarf. The star was a target of the Kepler/K2 mission and was observed by the EDEN project, a global network of 1-2 m class telescopes for detection and characterization of rocky exoplanets in the habitable zones of late-M dwarfs within 50 light year from the solar system. In the combination of the archived K2 data and our EDEN observations, a total of 872 flares have been detected, 861 with the K2 (860 in the short-cadence and 18 in the long-cadence data, with 17 long-cadence events having short-cadence counterparts) and 11 with EDEN. Wolf 359 has relatively strong flare activity even among flaring M dwarfs, in terms of the flare activity indicator (FA) defined as the integrated flare energy relative to the total stellar bolometric energy, where FA = Sigma E-f/integral L-bol dt similar to 8.93 x 10(-5) for the long-cadence flares, whereas for K2 short cadence and EDEN flares, the FA values are somewhat larger, FA approximate to 6.67 x 10(-4) and FA approximate to 5.25 x 10(-4), respectively. Such a level of activity, in accordance with the rotation period (P-rot), suggests the star to be in the saturation phase. The size of the starspots is estimated to be at least 1.87% +/- 0.59% of the projected disk area of Wolf 359. We find no correlation of FA with the stellar rotational phase. Our analysis indicates a flare frequency distribution in a power-law form of dN/dE proportional to E-alpha with alpha = 2.13 +/- 0.14, equivalent to an occurrence rate of flares E-f >= 10(31) erg about once per day and of superflares with E-f >= 10(33) erg approximately 10 times per year. These superflares may impact the habitability of system in multiple ways, the details of which are topics for future investigations.

引用

页数：14