An HST study of galactic inerstellar zinc and chromium

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

50

Absorption Spectra, Abundance, Chromium, Hydrogen, Interstellar Extinction, Interstellar Matter, Line Spectra, Lyman Alpha Radiation, Metallicity, Zinc, Disk Galaxies, Hubble Space Telescope, Milky Way Galaxy, Quasars

Scientific paper

We present a survey of interstellar Zn II and Cr II absorption extracted from the Hubble Space Telescope Goddard High Resolution Spectrograph (HST GHRS) data archive. We find clear evidence for an enhanced depletion of Zn from the gas phase with increasing fractional abundance of molecular hydrogen f(H2). Our lower limit to the Galactic interstellar metallicity is approximately 65% of the solar value as determined by the measured Zn abundances in the lowest f(H2) sightlines, (N(Zn)/N(H0tot) = -0.19 +/- 0.04. The correspondingly high depletion of Cr with respect to solar (N(Cr/N(H0tot) = -1.44 +/- 0.26 indicates that there are significant amounts of dust present in these lines of sight. The Galactic abundances of Zn and Cr in the ISM provide a fundamental reference point which is used to understand the metal enrichment and dust formation history of damped Lyman alpha QSO absorption-line systems, normally believed to arise from intervening precursors to modern disk galaxies. Although the spread in Zn abundances is large for both the local ISM and in damped Lyman alpha systems, we still find a substantial difference (factor of 4-10) in metallicity between the two sets. This survey and future observations of more distant objects which probe the full extent of the Milky Way halo provide a more complete picture of the enrichment and depletion characteristics of present-day galaxies.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

An HST study of galactic inerstellar zinc and chromium 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 HST study of galactic inerstellar zinc and chromium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An HST study of galactic inerstellar zinc and chromium will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1202323

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.