THE BARYONIC CONTRIBUTION OF LSBGS

• If M/L is constant w/ µ(0) and the same as for HSB galaxies:
  • Assume number density of galaxies is constant to 26.0 mag arcsec^-2

    Baryon contribution of LSBGs is 9× baryon contribution of HSBGs

    LSBGs contribute 40% of predicted baryons in the local Universe

  • If number density of galaxies is constant to 30.0mag arcsec^-2

    Baryon contribution of LSBGs is 17× baryon contribution of HSBGs

    LSBGs contribute 75% of predicted baryons in the local Universe

• If M/L increase to 6× its value between 22.0 and 24.0 mag arcsec^-2
  • Assume number density of galaxies is constant to 26.0 mag arcsec^-2

    Baryon contribution of LSBGs is 22× baryon contribution of HSBGs

    LSBGs contribute 97% of predicted baryons in the local Universe

  • If number density of galaxies is constant to 26.5 mag arcsec^-2

    Baryon contribution of LSBGs is 25× baryon contribution of HSBGs

    LSBGs contribute 100% of predicted baryons in the local Universe!

BUT....

While we were busy looking for baryons in LSB galaxies, other searches were also going on.

• 1998 Fukugita, Peebles, & Hogan published a summary of the observed baryon budget

• Found that hot intra-galactic & intra-cluster gas can account for all of the `missing' baryonic mass.

We now have up to 2× as many observed baryons as are predicted.

Oops. (But at least now were up to studying 10% of the Stuff in the Universe.)