A Study of Pi Aquarii During a Quasi-normal Star Phase: Refined Fundamental Parameters and Evidence for Binarity

Details A Study of Pi Aquarii During a Quasi-normal Star Phase: Refined Fundamental Parameters and Evidence for Binarity A Study of Pi Aquarii During a Quasi-normal Star Phase: Refined Fundamental Parameters and Evidence for Binarity

2002-03-20

arxiv.org/abs/astro-ph/0203357v1

Astronomy and Astrophysics

Astrophysics

26 pages (including 8 figs, 2 tables), accepted by ApJ

Scientific paper

10.1086/340751

We present the results of recent multicolor photometric and high-resolution spectroscopic observations of the bright Be star Pi Aquarii. Observational data collected from the literature were used to study the star's variations over the last four decades. The star is identified with the IR sources F22227+0107 in the IRAS Faint Point Source catalog and MSX5_G066.0066-44.7392 in the MSX catalog. The variations in near-IR brightness of Pi Aqr are found to be among the largest reported for Be stars. Since 1996, the star has shown only weak signs of circumstellar emission, which has allowed us to refine the fundamental stellar parameters: A_V=0.15 mag., T_eff=24000K, log g=3.9, and M_V=-2.95 mag. A weak emission component of the H-alpha line has been detected during the recent quasi-normal star phase. From analysis of the H-alpha line profiles, we find anti-phased radial velocity variations of the emission component and the photospheric absorption, with a period of 84.1 days and semi-amplitudes of 101.4 and 16.7 km/s, respectively. This result suggests that Pi Aqr may be a binary system consisting of stars with masses of M_1 sin^{3}i = 12.4 M_sun, M_2 sin^{3}i = 2.0 M_sun. We also estimate the orbital inclination angle to be between 50 and 75 degrees. We suggest that the photometric, spectroscopic, and polarimetric variations observed during the second half of the 20th century may be due to variable mass transfer between the binary components.

Affiliated with

Also associated with

No associations

Rating

A Study of Pi Aquarii During a Quasi-normal Star Phase: Refined Fundamental Parameters and Evidence for Binarity 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 A Study of Pi Aquarii During a Quasi-normal Star Phase: Refined Fundamental Parameters and Evidence for Binarity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Study of Pi Aquarii During a Quasi-normal Star Phase: Refined Fundamental Parameters and Evidence for Binarity will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-665485