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budhies:optical:masses

Tables

Here you can find the tables with the stellar masses and absolute magnitudes that I've calculated from the available SDSS photometry here:

Stellar Masses and Abs. Magnitudes

  • The tables contain: galaxy ID, redshift (ours, or literature),rest frame U B V R I mags, M_stellar (from Bell & de Jong 2001), SDSS (interpolated) rest frame magnitudes (g i r u z) , M_stellar (Zibetti et al. 2009)
  • Note that I only calculated M* for galaxies for which we had a trustable z_spec!!
  • Both mass estimates were calculated assuming a Kroupa IMF (for comparisson)!
  • I put all the info there for reference and because you might find it useful but if you're going to use the masses please use the Zibetti ones (to be consistent and always use the same)

FURTHER INFO:

Bell & de Jong (2001):

  • Formula I used: Log(M*/LB)= -0.51+1.45*(B-V)
  • This formula assumes Bruzual & Charlot SPS and Salpeter IMF
  • To convert to Kroupa I added -0.19 to the Log(M*)
  • To transform B into LB I used: LB=10^((5.36-B)/2.5)

Zibetti et al (2009):

  • Formula I used: Log(M*/Li) = -0.963 + 1.032 (g-i)
  • In this formula, they assume a Chabrier (2003) IMF
  • I converted it to a Krouppa IMF by adding +0.04 to the Log(M*).
  • To converted i into Li I used: Li=10^((4.53-i)/2.5)

Rest frame magnitudes were computed using InterRest (http://www.strw.leidenuniv.nl/~ent/InterRest/InterRest-distribution/introduction.html.utf8). And the cosmology used in calculating the rf magnitudes (and hence masses) was: (H0, W_l, W_m) = ( 70.0, 0.70, 0.30)

comparisson between the different mass estimates

This is a sanity check. The plots compare the 3 mass estimates: Bell & de Jong (2001), Zibetti et al. (2009) and the DR7 masses (all transformed to Kroupa IMF). All axes show Log(M*). The dashed lines show a 1-to-1 relation for comparisson!


Yara - 05/12/2011

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budhies/optical/masses.txt · Last modified: 2012/03/23 15:03 by 127.0.0.1