Presentation 1 : Oral/Invited
Models for Host Galaxy Extinction of Supernovae
Carl Pennypacker and Eugene Commins
We will describe simple models of extinction of supernovae light by
host galaxies. The spiral models are cylindrically symmetric, and
takeadvantage of reasonably well-understood scale heights of stars,
dust,and supernovae. Simple models for spheroidal galaxies have
also been
calculated. A prominent feature of the results of such models is that
the effects of increasing dust with redshift, which is expected in
models of star-formation through cosmic time, in fact do not cause
increased extinction of the supernova signal. Because of the
practical observational considertions of the limiting magnitude
achieved by
detectors and telescopes, the extinction effects for a wide range of
models tend to converge with increasing redshift. All of the models
exhibit virtually no extinction at the liiting magnitude/redshift of
the searches.
Presentation 2 : Oral/Invited
Some Implications of How Dust May Affect Existing Measurements of Omega
and Lambda
C. Pennypacker
Using preliminary results from a simple Monte Carlo of Commins and
the fitting program of Andre Tilquin, crude predictions of corrections
to the supernova-derived cosmological parameters Omega and Lambda can
begin to be discerned. There are large uncertainties in such
corrections, which I will endeavor to delineate. The spirit of this
talk is that it will hopefully contribute to the workshop dialog on how
to refine and/or modify new searches and measuremetns of distant
supernovae to reduce uncertainties due to dust in measuring the
cosmological parameters.