V/140 Photometric rotation periods of stars in α Per (Prosser+ 1997)
Rotation Periods of Open Cluster Stars. IV.
Prosser C.F., Grankin K.N.
<CfA Preprint Series, 4539 (1997)>
=1997cfa..rept.....P
=2013yCat.5140....0P 2013yCat.5140....0P
ADC_Keywords: Clusters, open ; Magnitudes ; Rotational velocities
Abstract:
We present the results from a photometric monitoring program of primarily
solar-type open cluster stars obtained during 1994 and 1995. Several
members of the α Persei cluster have been monitored and the
corresponding relation between coronal x-ray activity and rotation period
derived. The relation among mid-G/K type members illustrates both the
previously noticed downturn in LX/Lbol at high rotation rates and the
sharp decrease in coronal activity at long rotation periods as seen among
Pleiades stars. Intensive observation of one slowly rotating G-type member
of IC 4665 has enabled a period determination of 8-10 days to be made and
illustrates the need for (and limitations of) high quality observations.
Description:
Members of the Alpha Perseus open cluster were monitored and their
rotation periods and amplitudes were derived. These are combined with
their physical characteristics to estimate rotational velocities.
V-band observations of α Per stars were obtained by both C.P.
and K.G. Observations by C.P. were obtained with the Whipple
Observatory 48-in. telescope on Mt. Hopkins. Observations by K.G. were
obtained during photometric conditions at Mt. Maidanak (Tashkent)
Observatory, Uzbekistan using a 0.48m telescope. K.G. obtained
absolute V (Johnson) photometric magnitudes by observing five standard
stars several times each night. All together, rotational period
information was obtained for 35 members of the α Per cluster in
Aug-Dec 1994 and Oct, Dec 1995.
This work was never published in a refereed journal because Charles
Prosser was killed in an auto accident in 1998. See
http://aas.org/obituaries/charles-franklin-prosser-jr-1963-1998
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table12.dat 138 35 Observations, periods, ancillary data
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See also:
V/80 : Alpha Per Cluster Low-Mass Stars' Membership (Prosser 1992)
J/MNRAS/426/3403 : UKIDSS GCS alpha Persei members (Lodieu+, 2012)
J/A+A/488/409 : Radial velocities of α Per stars (Mermilliod+, 2008)
J/AJ/131/2967 : α Persei open cluster members (Makarov+, 2006)
J/A+A/395/813 : Alpha Per faint stars photometry (Barrado y Navascues+ 2002)
J/AN/319/215 : Alpha Per cluster low-mass members. II. (Prosser+, 1998)
J/AN/319/201 : Alpha Per cluster low-mass members. I. (Prosser+, 1998)
Byte-by-byte Description of file: table12.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Name Short star name
7- 23 A17 --- SName Simbad name of star
25- 29 F5.2 mag Vmag V-band magnitude
31- 34 F4.2 mag B-Vlit ? B-V color index from literature
36 A1 --- l_Vsini Limit flag on Vsini
37- 39 I3 km/s Vsini ? Projected rotational velocity from literature,
or lower limit of Vsini interval
40 A1 --- f_Vsini [-] If -, Vsini and B_Vsini are Vsini interval
41- 42 I2 km/s B_Vsini ? Upper limit on Vsini interval
44- 46 A3 --- r_Vsini ? Reference for Vsini (1)
48- 53 F6.3 d Prot Rotation period in days
55- 60 F6.2 h Phr Rotation period in hours
61 A1 --- u_Prot Uncertainty flag on Prot, Protd, and Amp
62 A1 --- n_Prot [*] Note on Prot estimation (2)
64- 67 F4.2 mag Amp Amplitude (peak-to-trough) of variability,
or lower limit of amplitude interval
68 A1 --- f_Amp [-] If -, Amp and B_Amp are Amplitude interval
69- 72 F4.2 mag B_Amp ? upper limit on amplitude interval
74- 80 E7.2 --- fap [0/1] False-alarm probability of periodogram
82- 84 I3 --- Nobs Number of observations
86- 90 A5 --- Obs Identity of observer(s) (initials of authors)
92-100 A9 --- Date Observation date (month and year)
102-112 A11 --- Drange Data range within observation
(JD-2440000 or JD-2450000)
114-117 F4.2 mag B-V Observed B-V color index, reddening-corrected
118 A1 --- n_B-V [a] a: B-V value estimated from V-I color index
120-123 F4.2 Rsun Rstar Estimated stellar radius in solar units
125-131 A7 --- SpType Approximate MK spectral type
133-137 F5.1 km/s Veq Equatorial rotational velocity, derived from
Prot and Rstar
138 A1 --- u_Veq Uncertainty flag on Veq
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Note (1): vsini reference as follows:
1 = Stauffer et al. (1985ApJ...289..247S 1985ApJ...289..247S, 1989ApJ...346..160S 1989ApJ...346..160S)
2 = Prosser (1992, Cat. V/80)
3 = Prosser (1994AJ....107.1422P 1994AJ....107.1422P)
4 = Prosser (1996, priv. comm.)
Note (2): Note as follows:
* = Except for AP121, the individual observations, rather than ensemble
averaging, were employed in the period analysis. For AP121, the period
estimate is based on 11 nightly mean values distributed over a 13 night
period.
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Acknowledgement:
Peter K.G. Williams (CfA), pwilliams( at )cfa.harvard.edu
References:
Prosser et al., Paper I 1993PASP..105..269P 1993PASP..105..269P
Prosser et al., Paper II 1993PASP..105.1407P 1993PASP..105.1407P
Prosser et al., Paper III 1995PASP..107..211P 1995PASP..107..211P
(End) Peter K. G. Williams [CfA] 23-Jul-2013