Astronomy and Astrophysics – Astrophysics
Scientific paper
Mar 2008
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008a%26a...480..187d&link_type=abstract
Astronomy and Astrophysics, Volume 480, Issue 1, March II 2008, pp.187-191
Astronomy and Astrophysics
Astrophysics
Stars: Chemically Peculiar, Stars: Individual: Hd 221756, Stars: Individual: Hd 220575, Stars: Oscillations, Stars: Variables: Δ Scuti
Scientific paper
Context: The λ Bootis stars are a chemically peculiar subgroup of main sequence A/F stars. Several of these fall into the instability strip of the δ Scuti stars and the whole spectroscopic group shows a high incidence of pulsational variability. Aims: We investigated the pulsational behaviour of the λ Bootis star 15 And (HD 221756) to determine as many intrinsic mode frequencies as possible for asteroseismic applications. Methods: The star was included as a secondary target for three telescopes during a campaign devoted to the β Cep stars 12 and 16 Lac, due to its proximity to these targets. 302.8 h of time-resolved photometry spanning 161.2 d were acquired and analyzed. Results: Our frequency analysis revealed f1 = 24.7887(2) c/d as the main pulsation frequency, with an amplitude of only 1.9(1) mmag. The residual periodogram suggests the presence of additional frequencies in an interval from 20 to 25 c/d, with very low amplitudes. We succeeded in detecting a second frequency f2 = 22.2580(9) with an amplitude of 0.6(1) mmag. Low-frequency light variations of the comparison star HD 220575 were revealed as well. Conclusions: The pulsational behaviour of 15 And as a typical λ Boo-type star is compared with that of δ Scuti stars with normal abundances and with metallic-line δ Scuti stars. We discuss the value of λ Boo stars in understanding accretion and mixing in pulsating stars. The difficulties in the selection of reliable comparison stars for such high-precision research are pointed out.
Dorokhov N. I.
Dorokhova T. N.
Handler Gerald
Rodríguez Eduardo
Udovichenko S. N.
No associations
LandOfFree
The pulsating λ Bootis star 15 Andromedae: results from a three-site photometry campaign 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 The pulsating λ Bootis star 15 Andromedae: results from a three-site photometry campaign, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The pulsating λ Bootis star 15 Andromedae: results from a three-site photometry campaign will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1035248