J/MNRAS/413/2218 Stellar rotation in Hyades and Praesepe (Delorme+, 2011)
Stellar rotation in the Hyades and Praesepe: gyrochronology and braking
time-scale.
Delorme P., Cameron A.C., Hebb L., Rostron J., Lister T.A., Norton A.J.,
Pollacco D., West R.G.
<Mon. Not. R. Astron. Soc., 413, 2218-2234 (2011)>
=2011MNRAS.413.2218D 2011MNRAS.413.2218D
ADC_Keywords: Clusters, open ; Photometry ; Proper motions ;
Parallaxes, trigonometric
Keywords: techniques: photometric - surveys - stars: rotation -
open clusters and associations: individual: Hyades, Praesepe
Abstract:
We present the results of photometric surveys for stellar rotation in
the Hyades and in Praesepe, using data obtained as part of the
SuperWASP exoplanetary transit-search programme. We determined
accurate rotation periods for more than 120 sources whose cluster
membership was confirmed by common proper motion and
colour-magnitude fits to the clusters' isochrones. This allowed us
to determine the effect of magnetic braking on a wide range of
spectral types for expected ages of ∼600Myr for the Hyades and
Praesepe. Both clusters show a tight and nearly linear relation
between J-Ks colour and rotation period in the F, G and K spectral
range. This confirms that loss of angular momentum was significant
enough that stars with strongly different initial rotation rates have
converged to the same rotation period for a given mass, by the ages of
Hyades and Praesepe.
Description:
We determined stellar rotation rates using data from the SuperWASP
camera array, located at the Observatorio del Roque de los Muchachos
on La Palma, Canary Islands. We used fields within ∼15° of the
Hyades centre (04:26.9 +15:52) with a good enough sampling and a large
enough time base (more than 56d) to efficiently probe rotation
periods from about a day up to about 20d without significant field to
field bias.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 35 21 Hyades SuperWASP fields used in this survey
table2.dat 113 62 Hyades members with SuperWASP rotation periods
table4.dat 113 52 Praesepe members with SuperWASP rotation periods
tablea1.dat 77 62 Cross-identifications and B, V photometry from
the literature of rotational variables with
Hyades membership probabilities greater than 0.5
tablea2.dat 77 52 Cross-identifications and B, V photometry from
the literature of rotational variables with
Praesepe membership probabilities greater than 0.5
--------------------------------------------------------------------------------
See also:
J/A+A/354/881 : Praesepe + Hyades Am stars RV (Debernardi+ 2000)
J/A+A/367/111 : A Hipparcos study of the Hyades cluster (de Bruijne+, 2001)
J/AJ/127/3579 : Radial velocities of Hyades stars (Paulson+, 2004)
J/MNRAS/257/257 : Proper motions in the Hyades (Reid 1992)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 h RAh Field centre right ascension (J2000)
4- 5 I2 min RAm Field centre right ascension (J2000)
7 A1 --- DE- Field centre declination sign (J2000)
8- 9 I2 deg DEd Field centre declination (J2000)
11- 12 I2 arcmin DEm Field centre declination (J2000)
14- 17 I4 --- Nimg Number of images
19- 20 I2 --- Nnig Usable nights
22- 31 A10 "YYYY-MM-DD" Date First night date
33- 35 I3 --- Nb Baseline (nights)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table[24].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- --- [1SWASP]
7- 25 A19 --- SWASP Swasp designation (JHHMMSS.ss+DDMMSS.s)
27- 38 A12 --- USNO USNO B-1.0 designation
40- 42 A3 --- X [Yes/No ] X-ray activity? (table2 only) (1)
44- 49 F6.3 d Per Rotation (spin) period (2)
51- 55 F5.3 d dPer ? Difference between the two period
determinations (2)
57- 61 F5.3 mag J-Ks 2MASS J-Ks colour index
63- 67 F5.2 mag Ksmag 2MASS Ks magnitude
70- 74 F5.2 mag Vmag ?=- V magnitude
76- 79 F4.1 deg Dist Distance to the cluster centre
81- 85 F5.1 mas/yr pmRA Proper motion along RA
87- 90 F4.1 mas/yr e_pmRA rms uncertainty on pmRA
92- 96 F5.1 mas/yr pmDE Proper motion along DE
98-101 F4.1 mas/yr e_pmDE rms uncertainty on pmDE
103-107 F5.2 mas plx ?=- Parallax (table2 only)
109-113 F5.3 --- Mmb Membership probability
--------------------------------------------------------------------------------
Note (1): traces whether or not Stern, Schmitt & Kahabka (1995,
Cat. J/ApJ/448/683) reported X-ray activity.
Note (2): if the object has been identified on two different seasons, the
period given is the average of the two periods whose difference is
indicated in dPer.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea[12].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- --- [1SWASP]
7- 25 A19 --- SWASP Swasp designation (JHHMMSS.ss+DDMMSS.s)
27- 38 A12 --- USNO USNO B-1.0 designation
40- 57 A18 --- OName Cluster member ID
59- 62 A4 --- SpType MK spectral type
65- 69 F5.2 mag Vmagl ? Literature V magnitude
71- 74 F4.2 mag B-Vl ? Literature B-V colour index
76- 77 I2 --- Ref ? Reference for photometry (1)
--------------------------------------------------------------------------------
Note (1): References as follows:
1 = Upgren, Weis & Deluca (1979AJ.....84.1586U 1979AJ.....84.1586U)
2 = Weis (1983PASP...95...29W 1983PASP...95...29W)
3 = Upgren, Weis & Hanson (1985AJ.....90.2039U 1985AJ.....90.2039U)
4 = Weis & Hanson (1988AJ.....96..148W 1988AJ.....96..148W)
5 = Stauffer (1982AJ.....87..899S 1982AJ.....87..899S)
11 = Klein Wassink (1927PGro...41....1K 1927PGro...41....1K)
12 = Jones & Stauffer (1991AJ....102.1080J 1991AJ....102.1080J)
13 = Johnson (1952ApJ...116..640J 1952ApJ...116..640J)
14 = Upgren et al. (1979AJ.....84.1586U 1979AJ.....84.1586U)
15 = Weis (1981PASP...93..437W 1981PASP...93..437W)
16 = Mermilliod et al. (1990A&A...235..114M 1990A&A...235..114M)
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-Dec-2011