J/MNRAS/516/4833 PN A66 70 i-band light curve (Jones+, 2022)
A detailed study of the barium central star of the planetary nebula Abell 70.
Jones D., Boffin H.M.J., Brown A.J., Zak J., Hume, G., Munday J.,
Miszalski B.
<Mon. Not. R. Astron. Soc. 516, 4833-4843 (2022)>
=2022MNRAS.516.4833J 2022MNRAS.516.4833J (SIMBAD/NED BibCode)
ADC_Keywords: Planetary nebulae ; Binaries, spectroscopic ; Photometry
Keywords: accretion, accretion discs - stars: AGB and post-AGB -
stars: chemically peculiar - planetary nebulae: general -
planetary nebulae: individual: PN A66 70, PN G038.1-25.4
Abstract:
We present a detailed study of the barium star at the heart of the
planetary nebula Abell 70. Time-series photometry obtained over a
period of more than ten years demonstrates that the
barium-contaminated companion is a rapid rotator with temporal
variability due to spots. The amplitude and phasing of the photometric
variability changes abruptly, however there is no evidence for a
change in the rotation period (P=2.06d) over the course of the
observations. The co-addition of 17 high-resolution spectra obtained
with VLT-UVES allow us to measure the physical and chemical properties
of the companion, confirming it to be a chromospherically-active, late
G-type sub- giant with more than +1dex of barium enhancement. We find
no evidence of radial velocity variability in the spectra, obtained
over the course of approximately 130d with a single additional point
some 8 years later, with the radial velocities of all epochs
approximately -10km/s from the previously measured systemic velocity
of the nebula. This is perhaps indicative that the binary has a
relatively long period (P>2yr) and high eccentricity (e>0.3), and
that all the observations were taken around radial velocity minimum.
However, unless the binary orbital plane is not aligned with the waist
of the nebula or the systemic velocity of the binary is not equal to
the literature value for the nebula, this would imply an unfeasibly
large mass for the nebular progenitor.
Description:
i-band photometry of the central star of the planetary nebula
Abell 70.
Objects:
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RA (2000) DE Designation(s)
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20 31 33.21 -07 05 18.03 PN A66 70 = PN G038.1-25.4
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
a70phot.dat 34 278 i-band photometry of the central star of PN A70
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Byte-by-byte Description of file: a70phot.dat
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Bytes Format Units Label Explanations
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3- 17 F15.7 d HJD Heliocentric Julian date
21- 26 F6.3 mag Dimag Change in apparent magnitude in i-band
30- 34 F5.3 mag e_Dimag Uncertainty on apparent magnitude
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Acknowledgements:
David Jones, djones(at)iac.es
(End) Patricia Vannier [CDS] 01-Sep-2022