Rotational modulation of the photospheric and chromospheric activity in the young, single K2-dwarf PW And

Details Rotational modulation of the photospheric and chromospheric activity in the young, single K2-dwarf PW And Rotational modulation of the photospheric and chromospheric activity in the young, single K2-dwarf PW And

2003-09-02

arxiv.org/abs/astro-ph/0309072v1

Astron.Astrophys.411:489-502,2003

Astronomy and Astrophysics

Astrophysics

Latex file with 20 pages, 21 figures tar'ed gzip'ed. Full postscript (text, figures and tables) available at http://www.ucm.

Scientific paper

10.1051/0004-6361:20031377

High resolution echelle spectra of PW And (HD~1405) have been taken during eight observing runs from 1999 to 2002. The detailed analysis of the spectra allow us to determine its spectral type (K2V), mean heliocentric radial velocity (V_hel = -11.15 km/s) rotational velocity (vsin{i} = 22.6 km/s), and equivalent width of the lithium line 6707.8 AA (EW(LiI) = 273 mAA). The kinematic (Galactic Velocity (U, V, W)) confirms its membership of the Local Association moving group, in agreement with the age (30 to 80 Myrs) inferred from the color magnitude diagram and the lithium equivalent width. Photospheric activity (presence of cool spots that disturb the profiles of the photospheric lines) has been detected as changes in the the bisectors of the cross correlation function (CCF) resulting of cross-correlate the spectra of PW And with the spectrum of a non active star of similar spectral type. These variations of the CCF bisectors are related to the variations in the measured radial velocities and are modulated with a period similar to the photometric period of the star. At the same time, chromospheric activity has been analyzed, using the spectral subtraction technique and simultaneous spectroscopic observations of the H_alpha, H_beta, NaI D_1 and D_2$, HeI D_3, MgI b triplet, CaII H&K, and CaII infrared triplet lines. A flare was observed during the last observing run of 2001, showing an enhancement in the observed chromospheric lines. A less powerful flare was observed on 2002 August 23. The variations of the chromospheric activity indicators seem to be related to the photospheric activity. A correlation between radial velocity, changes in the CCF bisectors and equivalent width of different chromospheric lines is observed with a different behaviour between epochs 1999, 2001 and 2002.

Affiliated with

Also associated with

No associations

Rating

Rotational modulation of the photospheric and chromospheric activity in the young, single K2-dwarf PW And does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Rotational modulation of the photospheric and chromospheric activity in the young, single K2-dwarf PW And, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rotational modulation of the photospheric and chromospheric activity in the young, single K2-dwarf PW And will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-493148