Access to Astronomical Catalogues

← Click to display the menu
J/ApJ/743/48   Stellar rotation periods and X-ray luminosities (Wright+, 2011)

The stellar-activity-rotation relationship and the evolution of stellar dynamos. Wright N.J., Drake J.J., Mamajek E.E., Henry G.W. <Astrophys. J., 743, 48 (2011)> =2011ApJ...743...48W
ADC_Keywords: Clusters, open ; Stars, late-type ; Stars, normal ; X-ray sources Magnetic fields Keywords: stars: activity - stars: coronae - stars: evolution - stars: late-type - stars: magnetic field - stars: rotation - X-rays: stars Abstract: We present a sample of 824 solar and late-type stars with X-ray luminosities and rotation periods. This is used to study the relationship between rotation and stellar activity and derive a new estimate of the convective turnover time. From an unbiased subset of this sample the power law slope of the unsaturated regime, LX/L{bol}∝Roβ, is fit as β=-2.70±0.13. This is inconsistent with the canonical β=-2 slope to a confidence of 5σ, and argues for an additional term in the dynamo number equation. From a simple scaling analysis this implies ΔΩ/Ω∝Ω0.7, i.e. the differential rotation of solar-type stars gradually declines as they spin down. Super-saturation is observed for the fastest rotators in our sample and its parametric dependencies are explored. Significant correlations are found with both the corotation radius and the excess polar updraft, the latter theory providing a stronger dependence and being supported by other observations. We estimate mass-dependent empirical thresholds for saturation and super- saturation and map out three regimes of coronal emission. Late F-type stars are shown never to pass through the saturated regime, passing straight from super-saturated to unsaturated X-ray emission. The theoretical threshold for coronal stripping is shown to be significantly different from the empirical saturation threshold (Ro<0.13), suggesting it is not responsible. Instead we suggest that a different dynamo configuration is at work in stars with saturated coronal emission. This is supported by a correlation between the empirical saturation threshold and the time when stars transition between convective and interface sequences in rotational spin-down models. Description: Photometric and derived stellar parameters for 824 solar- and late-type stars from nearby open clusters and the field, including rotation periods and X-ray luminosities. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file catalog.dat 184 824 Activity-rotation properties for 824 stars refs.dat 131 65 References
Byte-by-byte Description of file: catalog.dat
Bytes Format Units Label Explanations
1- 23 A23 --- Name Default source name (1) 25- 30 I6 --- HD ? Henry Draper catalog number (Cat. III/135) 32- 37 I6 --- HIP ? Hipparcos catalog number (Cat. I/239) 39- 45 A7 --- GJ Catalog of nearby stars source name (Cat. V/70) 47- 55 A9 --- GCVS ? General Catalog of Variable Stars source name (Cat. B/gcvs) 57- 72 A16 --- 2MASS 2MASS source name (Cat. II/246) 74- 75 I2 h RAh ? Right Ascension J2000 (hours) 77- 78 I2 min RAm ? Right Ascension J2000 (minutes) 80- 84 F5.2 s RAs ? Right Ascension J2000 (seconds) 86 A1 --- DE- ? Declination J2000 (sign) 87- 88 I2 deg DEd ? Declination J2000 (degrees) 90- 91 I2 arcmin DEm ? Declination J2000 (minutes) 93- 96 F4.1 arcsec DEs ? Declination J2000 (seconds) 98-105 A8 --- Cluster ? Name of open cluster that star is part of (or 'Field') 107-111 F5.1 pc Dist ? Distance to star (2) 113-117 F5.2 mag Vmag ? Observed V magnitude of star 119-122 F4.2 mag V-K Dereddened V-K colour of star (3) 124-127 A4 --- SpT ? Spectral type of star 129-131 A3 --- r_SpT ? Reference for spectral type, in refs.dat file 133-137 F5.2 [10-7W] logLx Logarithm of the intrinsic X-ray luminosity of the star 139-141 A3 --- r_logLx Reference for X-ray luminosity in refs.dat file 143-147 F5.2 d Prot Rotation period of the star 149-152 A4 --- r_Prot Reference for rotation period, in refs.dat file 154-157 F4.2 Msun M* Mass of the star (4) 159-162 F4.2 Rsun R* Radius of the star (4) 164-168 F5.2 Lsun L* Bolometric luminosity of the star (4) 170-173 I4 K Teff Effective temperature of the star (4) 175-178 F4.2 --- dcz Height of the radiative-convective boundary (as a function of the stellar radius) (4) 180-184 F5.2 [---] Lx/bol Logarithm of the X-ray to bolometric luminosity
Note (1): 202 star just identified by position. Note (2): Taken either from known cluster distances from the literature, individual stellar parallaxes or fits to main-sequence models (see paper). Note (3): Derived from spectral types where appropriate (see paper). Cluster stars dereddened using known cluster extinction. Note (4): from Siess et al. (2000A&A...358..593S) model.
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 4 A4 --- Ref Reference code 6- 24 A19 --- BibCode BibCode 26- 56 A31 --- Aut Author's name 58-131 A74 --- Com Comments
Acknowledgements: Nicholas Wright, nwright(at) History: * 09-Feb-2012: on-line version * 28-Feb-2013: some names corrected
(End) Nicholas Wright [SAO, USA], Patricia Vannier [CDS] 09-Feb-2012
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

catalogue service