Hubble Space Telescope Beryllium Abundances in the alpha Centauri System

Details Hubble Space Telescope Beryllium Abundances in the alpha Centauri System Hubble Space Telescope Beryllium Abundances in the alpha Centauri System

May 1997

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997apj...480..784p&link_type=abstract

Astrophysical Journal v.480, p.784

Astronomy and Astrophysics

Astronomy

29

Line: Identification, Stars: Abundances, Stars: Atmospheres, Stars: Individual Constellation Name: Alpha Centauri, Ultraviolet: Stars

Scientific paper

High signal-to-noise ratio Hubble Space Telescope Goddard High-Resolution Spectrograph spectra of alpha Centauri A (spectral type G2 V) and alpha Centauri B (spectral type K1 V) have been analyzed in the Be II lambda 3130 spectral region. Both stars offer an excellent opportunity for testing predictions of 9Be destruction since they are nearby, have a well-determined orbit and parallax, and thus have very well known physical parameters. A detailed spectrum synthesis has been made using a line list that has been carefully tested by comparison with the Sun and with metal-poor stars of different temperature and metallicity. Our analysis gives [Be/H] = +0.06 +/- 0.09 dex for alpha Cen A and -0.54 +/- 0.28 dex for alpha Cen B, using a model atmosphere with a metallicity [M/H] = +0.10. The implications of the new beryllium abundances and the previous lithium studies for models of stellar light-element depletion are then studied. Both the Sun and alpha Cen A are more highly depleted in lithium than younger stars; this is not consistent with standard stellar models. The Sun, alpha Cen A, and alpha Cen B have photospheric 9Be abundances lower than the current accepted solar meteoritic value. Because the initial 9Be abundance for the alpha Cen system is not known, and the depletion is much smaller than that for lithium, it is difficult to determine precise beryllium depletion factors for this system. However, because neither star is expected to deplete beryllium in standard models, the lower relative abundance of alpha Cen B might be evidence for main-sequence beryllium depletion. The theoretical implications of beryllium depletion are briefly discussed.

Affiliated with

Also associated with

No associations

Rating

Hubble Space Telescope Beryllium Abundances in the alpha Centauri System 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 Hubble Space Telescope Beryllium Abundances in the alpha Centauri System, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hubble Space Telescope Beryllium Abundances in the alpha Centauri System will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-835979