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HI Mass Function next up previous
Next: GOLDMiNe Up: Minutes of the 1st Previous: HIDEEP/HIJASS


Minutes of the talk on the:
      HI Mass Function

Steve Schneider (U. Mass.)


I note that "Z" plays an important role in what the ALFA surveys will look for:
HI rich objects few metals low Z
nearby low mass low redshift low z
Arecibo low zenith angle Low Z

Arecibo Blind Surveys

Several surveys have been undertaken in the recent past at Arecibo:

HI Selected Galaxies:

For the ADBS, we used the J band luminosities to try to understand the underlying population detected by the survey. At any given HI mass, there are a wide range of stellar luminosities (J band) $L_J \propto {\rm M}_{HI}^2$ almost.

Deriving the HIMF:

The HIMF derived from the ADBS is quite different from that derived from the AHISS by Zwaan et al. Among other things, we used different methods. So the questions are:

How tricky is it to actually derive HIMF? Coverage wins for volume, but if you do a shallow survey you are sampling only the nearby volume at low masses. The environment locally may be atypical. In particular, you have to worry about the Eddington bias.

Some caveats

Completeness:


Questions/Discussion:

Riccardo Don't you have a bias at low MHI so that you don't detect many?
Steve This is an HI selected sample.
Steve The same effect is seen in optical surveys because of the small volume.


next up previous
Next: GOLDMiNe Up: Minutes of the 1st Previous: HIDEEP/HIJASS



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