J/MNRAS/402/1380 Rotation velocities in Pleiades and αPer (Jackson+, 2010)
Are the spin axes of stars randomly aligned within a cluster ?
Jackson R.J., Jeffries R.D.
<Mon. Not. R. Astron. Soc., 402, 1380-1390 (2010)>
=2010MNRAS.402.1380J 2010MNRAS.402.1380J
ADC_Keywords: Clusters, open ; Rotational velocities
Keywords: methods: statistical - stars: formation -
open clusters and associations: individual: Pleiades -
open clusters and associations: individual: alpha Per
Abstract:
We investigate to what extent the spin axes of stars in young open
clusters are aligned. Assuming that the spin vectors lie uniformly
within a conical section, with an opening half-angle between
λ=0° (perfectly aligned) and λ=90° (completely
random), we describe a Monte Carlo modelling technique that returns a
probability density for this opening angle given a set of measured
sini values, where i is the unknown inclination angle between a
stellar spin vector and the line of sight.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 60 82 *Estimated values of sini for stars in the
Pleiades and α Per clusters
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Note on table3.dat : using the Barnes-Evans relation in equation (11), a
mean distance of 131.8±2.4pc and a colour excess of 0.032 for the
Pleiades and a distance of 176.2±4.9pc and a colour excess of 0.10
for the α Per cluster.
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See also:
J/A+A/320/74 : Radial velocities of Pleiades members (Mermilliod+ 1997)
J/A+A/323/139 : K magnitude of Pleiades low-mass binaries (Bouvier+ 1997)
J/A+A/335/183 : Pleiades low-mass stars rotational velocities (Queloz+ 1998)
J/A+A/416/125 : RI photometry in α Per and Pleiades (Deacon+, 2004)
J/A+A/488/409 : Radial velocities of α Per stars (Mermilliod+, 2008)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 7 A7 -- Star Star name
9- 14 F6.3 d Per Rotation (spin) period
16 A1 --- r_Per Period reference (1)
18- 22 F5.1 km/s vsini Rotational velocity
24 A1 --- r_vsini Rotational velocity reference (1)
26- 30 F5.2 mag Vmag Mean apparent V magnitude
32- 36 F5.2 mag Kmag Mean apparent 2MASS K magnitude
38- 41 F4.2 mag V-K V-K(CIT) colour index (2)
43- 46 F4.2 mag Vamp Amplitude of the light curve modulation in V
48- 52 F5.3 arcsec Diam Estimated stellar diameter
54- 57 F4.2 --- sini Estimate of sini
59- 60 A2 -- bin [*] ** for stars identified as probable binaries
and excluded from the analysis of the
sini distribution
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Note (1): References as follows:
a = Krishnamurthi et al. (1998ApJ...493..914K 1998ApJ...493..914K)
b = Marilli, Catalano & Frasca (1997MmSAI..68..895M 1997MmSAI..68..895M)
c = Prosser et al. (1995PASP..107..211P 1995PASP..107..211P)
d = Prosser et al. (1993PASP..105..269P 1993PASP..105..269P)
e = Messina (2001A&A...371.1024M 2001A&A...371.1024M)
f = Queloz et al. (1998, Cat. J/A/A/335/183)
h = Stauffer & Hartmann (1987ApJ...318..337S 1987ApJ...318..337S)
i = Soderblom et al. (1993, Cat. J/ApJS/85/315)
j = Stauffer et al. (1989ApJ...346..160S 1989ApJ...346..160S)
k = Stauffer et al. (1985ApJ...289..247S 1985ApJ...289..247S)
l = Prosser et al. (1993PASP..105..269P 1993PASP..105..269P)
m = Prosser & Gramkin (1993, CFA Prerints Ser. 4539, 376, 1109)
n = Bouvier (1996, Cat. J/A+AS/120/127)
p = O'Dell et al. (1994MNRAS.268..181O 1994MNRAS.268..181O)
Note (2): K(CIT)=K(2MASS)+ 0.024
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Acknowledgements:
Richard Jackson, rjj(at)astro.keele.ac.uk>
(End) Patricia Vannier [CDS] 19-Jul-2010