Galaxies with Background QSOs, I: A Search for Strong Galactic H-alpha
  Lines
  A search for emission lines in foreground galaxies in quasar spectra (z(gal)
< z(QSO)) of the Sloan Digital Sky Survey (SDSS) data release 5 (DR5) reveals
23 examples of quasars shining through low redshift, foreground galaxies at
small impact parameters (< 10 kpc). About 74,000 quasar spectra were examined
by searching for narrow H{\alpha} emission lines at z < 0.38, at a flux level
greater than 5 \times 10^-17 ergs cm^-2 s^-1, then confirming that other
expected emission lines of the H II regions in the galaxy are detected. The
galaxies were deblended from the quasar images to get colors and morphologies.
For cases that allow the galaxy and the quasar to be deblended, the galaxies
are blue (0.95 <(u-r)< 1.95). Extinction and reddening through the galaxies is
determined from the (g-i) color excesses of the quasars. These reddening values
are compared with the flux ratio of H{\alpha} to H{\beta}, which reflect the
extinction for an undetermined fraction of the sightline through each galaxy.
No trends were found relating E(B-V)_(g-i), impact parameter (b), and (u-r) for
the galaxies or between E(B-V) derived from (g-i) and that derived from
H{\alpha}/H{\beta}. Comparison with previous studies of quasar absorption
systems indicate our sample is more reddened, suggesting disk-dominated
absorber galaxies. Measurement or limits on galactic, interstellar Ca II and Na
I absorption lines are given from the quasar spectrum. No trends were found
relating Ca II equivalent width (W (Ca II)) or Na I equivalent width (W (Na I))
to b, but a correlation of r_s = -0.77 ({\alpha} = 0.05) was found relating W
(Ca II) and E(B-V)(g-i) .
