J/A+A/708/A225 AD Leo B light curve (Schmercz+, 2026)
Sub-second cadence structure of optical flares on AD Leo.
Schmercz B., Seli B., Vida K., Kriskovics L., Gorgei A., Olah K., Regaly Zs.
<Astron. Astrophys. 708, A225 (2026)>
=2026A&A...708A.225S 2026A&A...708A.225S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, late-type ; Stars, flare ; Photometry ; Optical
Keywords: stars: activity - stars: flare - stars: late-type -
stars: individual: AD Leo
Abstract:
Stellar flares are sudden brightenings caused by magnetic reconnection
and are frequently observed on late-type stars. High-cadence
photometry of flares provides valuable insights into the mechanisms of
these events, yet such observations remain scarce.
We seek to explore the sub-second fine structure of stellar flares and
assess the information content in high-speed photometry.
New 0.3 s-cadence photometry from a six-year-long observing campaign
of the active M-dwarf AD Leo is presented. We use time-frequency
analysis to detect quasi-periodic pulsations in the decay phase of
flares. We explore statistical measures of time series complexity of
the detected flares to quantify the information gain achievable with
high-cadence photometry.
We detect 42 flares in 211 hours of observations. The flare frequency
distribution is consistent with the previous literature. We find no
quasi-periodic pulsations with periods below a few seconds, and
identify two candidate signals with periods around 1 and 3 min. Using
different measures of complexity on the binned flare light curves we
confirm the advantages of high observing cadence. However, we also
find a plateau up to a binning of ∼4-5s for a few complex flares,
suggesting that an exposure time of a few seconds is usually enough to
retain most of the information carried by a single-filter observation.
New photometric observations of AD Leo revealed sub-structures of
flare light curves on the timescale of a few seconds, but we found no
features on timescales below that.
Description:
We present the complete light curve of AD Leo observed with the RCC
telescope and EMCCD camera at Piszkesteto Mountain Station, Konkoly
Observatory.
Objects:
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RA (2000) DE Designation(s)
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10 19 36.28 +19 52 12.0 AD Leo = BD+20 2465
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
adleo.dat 21 2467311 Full observed light curve of AD Leo
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See also:
J/A+A/637/A13 : AD Leo high resolution spectra (Muheki+, 2020)
J/A+A/638/A5 : HD 285507 and AD Leo light and velocity curves (Carleo+, 2020)
J/A+A/666/A143 : AD Leo RV and stellar activity indices (Kossakowski+, 2022)
J/A+A/669/A118 : AD Leo spectral observations (Wollmann+, 2023)
J/A+A/674/A110 : Gl 388 (AD Leo) RV curves (Carmona+, 2023)
J/A+A/676/A56 : Large-scale magnetic field of AD Leo (Bellotti+, 2023)
Byte-by-byte Description of file: adleo.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d HJD Heliocentric Julian Date
16- 21 F6.3 mag Bmag Magnitude in B Band
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Acknowledgements:
Blanka Schmercz, schmercz.blanka(at)csfk.org
(End) Patricia Vannier [CDS] 27-Jan-2026