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J/A+A/531/A8   Activity indexes and velocities for 890 stars   (Jenkins+, 2011)

Chromospheric activities and kinematics for solar type dwarfs and subgiants. Jenkins J.S., Murgas F., Rojo P., Jones H.R.A., Day-Jones A.C., Jones M.I., Clarke J.R.A., Ruiz M.T., Pinfield D.J. <Astron. Astrophys. 531, A8 (2011)> =2011A&A...531A...8J
ADC_Keywords: Stars, nearby ; Stars, dwarfs ; Stars, M-type ; Radial velocities ; Rotational velocities ; Space velocities Keywords: stars: fundamental parameters - stars: activity - stars: kinematics and dynamics - stars: atmospheres - stars: rotation - planetary systems Abstract: In this work we present chromospheric activity indices, kinematics, radial-velocities, and rotational velocities for more than 850 FGK-type dwarfs and subgiant stars in the southern hemisphere and test how best to calibrate and measure S -indices from echelle spectra. We measured our parameters using the high-resolution and high-S/N FEROS echelle spectra acquired for this purpose. Results. We confirm the bimodal distribution of chromospheric activities for such stars and highlight the role that the more active K-dwarfs play in biasing the number of active stars. We show that the age-activity relationship does appear to continue to ages older than the Sun if we simply compare main sequence stars and subgiant stars with an offset of around 2.5Gyr between the peaks of both distributions. Also we show evidence of an increased spin-down timescale for cool K dwarfs compared with earlier F and G type stars. We highlight that activities drawn from low-resolution spectra (R<2.500') significantly increase the rms scatter when calibrating onto common systems of measurements like the Mt. Wilson system. Also we show that older and widely used catalogues of activities in the south appear to be offset compared to more recent works at the ∼0.1dex level in logR'HK through calibrator drift. In addition, we show how kinematics can be used to preselect inactive stars for future planet search projects. We see the well known trend between projected rotational velocity and activity, however we also find a correlation between kinematic space velocity and chromospheric activity. It appears that after the Vaughan-Preston gap there is a quick step function in the kinematic space motion towards a significantly broader spread in velocities. We speculate on reasons for this correlation and provide some model scenarios to describe the bimodal activity distribution through magnetic saturation, residual low level gas accretion, or accretion by the star of planets or planetesimals. Finally, we provide a new empirical measurement for the disk-heating law, using the latest age-activity relationships to reconstruct the age-velocity distribution for local disk stars. We find a value of 0.337±0.045 for the exponent of this power law, in excellent agreement with those found using isochrone fitting methods and with theoretical disk-heating models. Description: The activities, rotational velocities, radial velocities and kinematic space motions are presented for over 850 dwarf and subgiant FGK type stars. The chromospheric activities were measured using the CaII HK lines and high resolution and high S/N FEROS spectra. The radial velocities were determined by cross-correlation with a number of template stars and the rotational velocities were measured using the cross-correlation functions from this analysis. The UVW kinematic space motions were then determined using these radial velocities and the latest Hipparcos proper motions. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 90 890 Stellar basic physical parameters, chromospheric indices, rotational velocities, radial velocities and kinematic UVW space velocities
See also: I/239 : The Hipparcos and Tycho Catalogues (ESA 1997) Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 3 A3 --- --- [HIP] 4- 9 I6 --- HIP HIP number 11- 15 F5.3 mag B-V Johnson B-V colour index 17- 20 F4.2 mag Vmag Johnson V magnitude 22- 26 F5.3 --- SMW Mount Wilson activity S-index 28- 32 F5.3 --- e_SMW ? rms uncertainty on SMW 34- 38 F5.2 [---] log(R'HK) Chromopspheric activity index 40- 43 F4.1 km/s vsini ? Rotational velocity 45- 50 F6.1 km/s RV ? Radial velocity 52- 54 F3.1 km/s e_RV ? rms uncertainty on RV 56- 61 F6.1 km/s Uvel ? U kinematic component 63- 66 F4.1 km/s e_Uvel ? rms uncertainty on Uvel 68- 73 F6.1 km/s Vvel ? V kinematic component 75- 78 F4.1 km/s e_Vvel ? rms uncertainty on Vvel 80- 85 F6.1 km/s Wvel ? W kinematic component 87- 90 F4.1 km/s e_Wvel ? rms uncertainty on Wvel
Acknowledgements: James S. Jenkins, jjenkins(at)das.uchile.cl
(End) James S. Jenkins [UdeC, Chile], Patricia Vannier [CDS] 12-Apr-2011
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

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