The Nearby Supernova Factory

The Dark Energy Task Force has underscored the importance of a large sample of well-observed, low-redshift Type Ia supernovae for cosmology. Such a sample will constrain the supernova luminosity function, and improve control of systematic uncertainties and photometric calibration at high redshift. A few hundred such supernovae would also anchor the Hubble diagram, deflating statistical uncertainties currently due to the small existing sample. The Nearby Supernova Factory (SNfactory) is acquiring time-series spectrophotometry of such a sample of these events at redshifts 0.03 < z < 0.08. To avoid bias with respect to host galaxy type or luminosity, the SNfactory uses wide-field images taken with the QUEST-II camera on the Samuel Oschin 1.2-meter telescope at Mt. Palomar, covering up to 500 square degrees of sky per night to a depth of R=20.5. Promising supernova candidates are forwarded to the Supernova Integral Field Spectrograph (SNIFS); a dedicated, automated, and remotely supervised instrument mounted on the University of Hawaii 2.2-meter telescope on Mauna Kea. I will outline the motivation behind the project, discuss our automated operations, and showcase some recent results in this talk. Many concepts behind the SNfactory will sound familiar to those planning future wide-field surveys like LSST, where a centralized survey pipelines transients to a distributed network of followup facilities.