An Upper Limit for the Deuterium Abundance in the Halo Star HD 140283

Details An Upper Limit for the Deuterium Abundance in the Halo Star HD 140283 An Upper Limit for the Deuterium Abundance in the Halo Star HD 140283

Dec 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994aas...185.9805l&link_type=abstract

American Astronomical Society, 185th AAS Meeting, #98.05; Bulletin of the American Astronomical Society, Vol. 26, p.1479

Astronomy and Astrophysics

Astronomy

1

Scientific paper

Because of the possible enhanced deuterium abundance of D/H = 2.5 10(-4) (the ISM D/H = 1.65x10(-5) ) recently reported in quasar absorption spectra, we searched for the D_alpha line at 6561 A in the metal-poor halo star HD 140283 (G2IV, [Fe/H] = -2.6; Teff= 5700K). We observed HD 140283 using the .9m KPNO coude feed and the 2.7m McDonald Observatory telescopes with echelle spectrographs having a resolution Delta lambda = .05 A/pixel with S/N= 200 and Delta lambda = .11 A/pixel with S/N = 600 respectively. We did not detect the D_alpha line and compared our results to model atmosphere calculations for this star. We estimate an upper limit of D/H < 1x10(-5) which is smaller than the primordial or and Early Galactic D/H = 8x10(-5) . Since D is destroyed via reactions with protons at T > 5x10(5) K, the atmospheric deuterium has probably been destroyed during the pre-main sequence convection phase. Because (7) Li, (9) Be, and (11) B have all been detected in this star (Li/H=1.5x10(-10) and B/H=2.9x10(-12) ) and Li is destroyed at T > 2.5x10(6) K, the temperature at the bottom of the pre-main sequence convection zone is 1x10(6) K < T < 2.5x10(6) .K

Affiliated with

Also associated with

No associations

Rating

An Upper Limit for the Deuterium Abundance in the Halo Star HD 140283 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 An Upper Limit for the Deuterium Abundance in the Halo Star HD 140283, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An Upper Limit for the Deuterium Abundance in the Halo Star HD 140283 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1322799