J/AJ/129/2026 Differential photometry of HD 8801 (Henry+, 2005)
HD 8801: a unique single Am star with γ Doradus and δ Scuti
pulsations.
Henry G.W., Fekel F.C.
<Astron. J., 129, 2026-2033 (2005)>
=2005AJ....129.2026H 2005AJ....129.2026H
ADC_Keywords: Stars, variable ; Stars, Am ; Photometry, uvby
Keywords: δ Scuti - stars: chemically peculiar - stars: early-type -
stars: fundamental parameters - stars: oscillations -
stars: variables: other
Abstract:
We have discovered the first example of a star pulsating intrinsically
with both γ Doradus and δ Scuti frequencies. HD 8801 is an
Am metallic-line star that appears to be single. Since the vast
majority of Am stars are members of binary systems with periods less
than 1000 days and also do not pulsate, HD 8801 possesses a very
unusual, if not unique, combination of physical properties. Our
photometry, acquired with an automatic telescope at Fairborn
Observatory, resolves six independent pulsation periods between 0.048
and 0.404 days. The two longest periods lie within the range of
γ Dor variables, while the four shorter periods are within the
range of δ Sct stars.
Description:
The photometric observations in this paper were acquired on nine
nights between 2003 November 17 and December 6 with the T12 0.8m
automatic photoelectric telescope (APT) at Fairborn Observatory.
Objects:
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RA (2000) DE Designation(s)
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01 27 26.7 +41 06 04 HD 8801 = ADS 1151 A
01 26 16.9 +42 18 40 HD 8672 = AG+42 128
01 20 04.9 +41 58 14 HD 8007 = AG+41 134
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 44 473 Photometric observations of HD 8801
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 F12.4 --- HJD Heliocentric Julian Date
14- 20 F7.4 mag b(p-c1) HD8801-HD8672 differential magnitude in b (1)
22- 28 F7.4 mag y(p-c1) HD8801-HD8672 differential magnitude in y (1)
30- 36 F7.4 mag b(c1-c2) HD8672-HD8007 differential magnitude in b (1)
38- 44 F7.4 mag y(c1-c2) HD8672-HD8007 differential magnitude in y (1)
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Note (1): The measurements of our program star HD 8801 (V=6.42, B-V=0.31, F1m)
were made differentially with respect to the two comparison stars
HD 8672 (V=7.23, B-V=0.26, F0) and HD 8007 (V=6.95, B-V=0.35, F0).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 31-Aug-2005