J/A+A/695/L2 Halpha spectra of UX Ari (Cao+, 2025)
A filament eruption on the RS CVn-type star UX Ari.
Cao D., Gu S.
<Astron. Astrophys. 695, L2 (2025)>
=2025A&A...695L...2C 2025A&A...695L...2C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Spectra, optical
Keywords: Sun: coronal mass ejections (CMEs) - Sun: filaments, prominences -
stars: chromospheres - stars: coronae - stars: flare
Abstract:
Stellar flares can be accompanied by filament or prominence eruptions,
which may lead to stellar coronal mass ejections (CMEs) that have
significant impacts on surrounding exoplanets and stellar evolution.
We report the capture of a filament eruption associated with an
optical flare on the RS CVn-type star UX Ari.
Based on high-resolution spectroscopic observations, we investigated
the Doppler-shifted absorption features appeared in the Hα
flaring spectra, which can be indicative of a filament eruption.
A huge optical flare was observed, which lasted for at least 150 hours
and released an energy of about 1.47x1037erg in the Hα line.
The corresponding bolometric white-light energy is converted to be
1.03x1039erg, indicating that the flare is comparable to the most
intense stellar superflares. A blueshifted absorption feature with a
bulk velocity of -143.9km/s emerged in the Hα line region during
the initial phase of the flare, which then decelerated and turned into
redshifted absorption. This suggests that a filament eruption happened
and ultimately fell back toward the star, suggesting that it
represents a failed filament eruption. The erupted filament mass of
8.5-15.0x1020g and the kinetic energy of 8.8-15.5x1034erg are
derived. Furthermore, the relationship between the filament eruption
and the flare is likely characterized by a sympathetic eruption.
Description:
The reduced spectra in the H-alpha spectral region are presented. The
observing time can be found in Table A.1 of the paper. Each spectrum
consists of two columns of data: wavelength and normalized intensity.
Objects:
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RA (2000) DE Designation(s)
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03 26 35.37 +28 42 54.2 UX Ari = HD 21242
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 48 22 Observing information for UX Ari
sp/* . 14 Individual spectra
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See also:
J/A+A/370/974 : Radial velocities of UX Ari (Duemmler+, 2001)
J/A+A/402/1033 : BV photometry of UX Ari in 1987-2002 (Aarum Ulvas+, 2003)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "date" Date Observation date
12- 15 I4 s ExpTime Exposure time
17- 24 F8.3 d HJD Heliocentric Julian date (HJD-2450000)
26- 30 F5.3 --- Phase Phase
32- 48 A17 --- FileName Name of the spectrum file in subdirectory sp
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Byte-by-byte Description of file: sp/*
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Bytes Format Units Label Explanations
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1- 12 F12.7 0.1nm lambda Wavelength
15- 23 F9.7 --- Int Normalized intensity
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Acknowledgements:
Dongtao Cao, dtcao(at)ynao.ac.cn
(End) Patricia Vannier [CDS] 21-Feb-2025