J/A+A/504/1021 BV(RI)C light curves of V405 And (Vida+, 2009)
Photospheric and chromospheric activity in V405 Andromedae. An M dwarf binary
with components on the two sides of the full convection limit.
Vida K., Olah K., Kovari Zs., Korhonen H., Bartus J., Hurta Zs.,
Posztobanyi K.
<Astron. Astrophys. 504, 1021 (2009)>
=2009A&A...504.1021V 2009A&A...504.1021V (SIMBAD/NED BibCode)
ADC_Keywords: Stars, dwarfs ; Magnetic fields ; Photometry, CCD ;
Photometry, UBVRI
Keywords: stars: activity - stars: flare - stars: individual: V405 And -
stars: late-type - stars: low-mass - starspots
Abstract:
We investigate the fast-rotating (Porb=Prot=0.465d), active dwarf
binary V405 And (M0V+M5V) using photometric BV(RI)C and optical
spectroscopic data. The light variation is caused by the combined
effect of spottedness and binarity with a small eclipse. We estimate
the system parameters from the available light and radial velocity
curves. Three flare events occurred during the observations: two were
found in the spectroscopic data and one was observed photometrically
in BV(RI)C colours. An interesting eruptive phenomenon emerged from
the photometric measurements that can be interpreted as a series of
post-flare eruptions lasting for at least 3 orbits (rotations) of the
system, originating from trans-equatorial magnetic loops, which
connect the active regions in the two hemispheres. The two components
of V405 And have masses well over and below the theoretical limit of
full convection. This rare property makes the binary an ideal target
for observing and testing models for stellar dynamo action.
Description:
Differential BV(RI)_C photometry of V405 And, obtained by the 60cm
telescope of the Konkoly Observatory at Svabhegy, Budapest and the 1m
RCC telescope at Piszkesteto station (comparison star:
GSC 03298-00148).
Objects:
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RA (2000) DE Designation(s)
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02 22 25.86 +47 29 19.8 V405 And = GSC 03298-01172
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
24.dat 51 334 BV(RI)_C photometry with the 60cm telescope
rcc.dat 51 2374 BV(RI)_C photometry with the 1m RCC telescope
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Byte-by-byte Description of file: 24.dat rcc.dat
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Bytes Format Units Label Explanations
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1- 12 F12.6 d HJD Heliocentric Julian date (HJD-2400000)
14- 22 F9.6 mag Bmag Johnson B magnitude
24- 32 F9.6 mag Vmag Johnson V magnitude
34- 42 F9.6 mag Rcmag Cousins R magnitude
44- 51 F8.6 mag Icmag Cousins I magnitude
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Acknowledgements:
Krisztian Vida, vidakris(at)konkoly.hu
(End) Patricia Vannier [CDS] 26-Sep-2025