Transcript SDSS-II Supernova Survey B. Dilday, J.Frieman, R.Kessler, SDSS-II SN Team May 2008 In 3 three-month observing seasons, the SDSS-II Supernova Survey used a 2.5m telescope.

SDSS-II Supernova Survey
B. Dilday, J.Frieman, R.Kessler, SDSS-II SN Team
May 2008
In 3 three-month observing seasons, the
SDSS-II Supernova Survey used a 2.5m
telescope at Apache Point Observatory
in southern New Mexico to discover the
largest number of spectroscopically
confirmed SNe of any survey, including
~ 500 SNe Ia at reshifts z < 0.4.
Most precise low-redshift SN Ia rate ( z < .12)
with first season (2005) sample only:
Dilday et al., 2008
Continuing SN Ia rate study to higher redshift
First Cosmology paper on 99 SDSS, 26 Nearby, 64 SNLS & 56 ESSENCE SNe Ia .
Includes detailed systematic studies and MLCS-vs-SALT2 method comparisons.
(Kessler, etal., 2008)
Additionally several hundred
photometrically identified SN Ia
candidates are being targeted for hostgalaxy spectroscopic redshifts (~ 200
already obtained).
Also studying rate versus host-galaxy
properties (age, mass …)
(Smith et al., 2008)
Frieman et. Al., 2008
Sako et al., 2008, Zheng et al., 2008
Type IIn-like
Peculiar
SN 2005gj:
possible
type Ia in dense
circumstellar
environment
Approximately 1000 spectra taken of the
spectroscopically confirmed SNe Ia. Compiling
a data base and automating procedure to extract
spectral features.
240 total
Prieto at al., 2007
Type Ia-like
New technique for precise SN flux
measurement:
“Scene-Model Photometry” models
underlying sky and galaxy without
pixel re-sampling ==> no pixel
correlations and correct statistical
errors.
Holtzman et al., 2008
The National Science Foundation
SNANA: KICP researcher Kessler has developed a public software package including Monte Carlo
simulation, light curve fitter, and cosmology fitter. Developed for SDSS, it has been generalized for
other surveys such as DES & LSST. Community software improves sharing of ideas, communication
among groups, reproducibility, comparisons of different techniques, overall efficiency of analysis.
Recently held “1st SNANA Training Day” with over a dozen new participants.
measure underlying
study impact of spectroscopic inefficiency
Simulate & fit all surveys with same program
extinction distribution