J/MNRAS/377/741 VIc photometry of NGC 2516 (Irwin+, 2007)
The Monitor project: rotation of low-mass stars in the open cluster NGC 2516.
Irwin J., Hodgkin S., Aigrain S., Hebb L., Bouvier J., Clarke C.,
Moraux E., Bramich D.M.
<Mon. Not. R. Astron. Soc., 377, 741-758 (2007)>
=2007MNRAS.377..741I 2007MNRAS.377..741I
ADC_Keywords: Clusters, open ; Photometry, UBVRI ; Photometry, Cousins
Keywords: techniques: photometric - surveys - stars: rotation -
open clusters and associations: individual: NGC 2516
Abstract:
We report on the results of an i-band time-series photometric survey
of NGC2516 using the Cerro Tololo Inter-American Observatory (CTIO)
4-m Blanco telescope and 8k Mosaic-II detector, achieving better than
1 per cent photometric precision per data point over 15≲i≲19.
Candidate cluster members were selected from a V versus V-I
colour-magnitude diagram over 16<V<26 (covering masses from
0.7M☉ down to below the brown dwarf limit), finding 1685
candidates, of which we expect ∼1000 to be real cluster members,
taking into account contamination from the field (which is most severe
at the extremes of our mass range). Searching for periodic variations
in these gave 362 detections over the mass range
0.15≲M/M☉≲0.7. The rotation period distributions were found to
show a remarkable morphology as a function of mass, with the fastest
rotators bounded by P>0.25d, and the slowest rotators for
M≲0.5M☉ bounded by a line of P∼M3, with those for
M≳0.5M☉ following a flatter relation closer to P ∼ constant.
Models of the rotational evolution were investigated, finding that the
evolution of the fastest rotators was well reproduced by a
conventional solid body model with a mass-dependent saturation
velocity, whereas core-envelope decoupling was needed to reproduce the
evolution of the slowest rotators. None of our models were able to
simultaneously reproduce the behaviour of both populations.
Description:
Photometric parameters and rotation periods are presented for 362
candidate members of NGC 2516. The period, i-band amplitude,
interpolated mass and radius (from the NextGen models of Baraffe et
al. (1998. Cat. J/A+A/337/403), derived using the I magnitudes), as
used for the analysis in the paper, are given (where available).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 73 362 Positions, photometry and rotation periods
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See also:
J/A+A/312/818 : NGC 2516 X-ray sources (Dachs+, 1996)
J/ApJ/588/1009 : Chandra X-ray observations of NGC 2516 (Damiani+, 2003)
J/ApJ/606/466 : X-ray variability in NGC 2516 (Wolk+, 2004)
J/A+A/450/993 : XMM survey of NGC 2516 (Pillitteri+, 2006)
J/A+A/456/977 : XMM observations of NGC 2516 stars (Marino+, 2006)
J/MNRAS/370/954 : The Monitor project: M34 (Irwin+, 2006)
J/A+A/375/863 : Photometry in NGC 2516 (Jeffries+, 2001)
J/AJ/123/290 : UBVI CCD photometry of NGC 2516 (Sung+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- --- [N2516-]
7- 14 A8 --- [IHA2007] Identifier in NGC 2516, N-N-NNNN
16- 17 I2 h RAh Right ascension (J2000)
19- 20 I2 min RAm Right ascension (J2000)
22- 26 F5.2 s RAs Right ascension (J2000)
28 A1 --- DE- Declination sign
29- 30 I2 deg DEd Declination (J2000)
32- 33 I2 arcmin DEm Declination (J2000)
35- 38 F4.1 arcsec DEs Declination (J2000)
40- 44 F5.2 mag Vmag Johnson V magnitude
46- 50 F5.2 mag Icmag Cousins I magnitude
52- 57 F6.3 d Per Photometric period
59- 63 F5.3 mag Iamp Sine curve fit amplitude (i-band)
65- 68 F4.2 solMass Mass Adopted mass from models
70- 73 F4.2 solRad Rad Adopted radius from models
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Acknowledgements:
Jonathan Irwin, jmi(at)ast.cam.ac.uk
(End) Jonathan Irwin [IoA, Cambridge Univ.], Patricia Vannier [CDS] 09-Oct-2007