Light Curves of 213 Type Ia Supernovae from the ESSENCE Survey

TL;DR

This paper presents detailed photometric and spectroscopic data for 213 Type Ia supernovae from the ESSENCE survey, improving calibration accuracy and assessing systematic biases in their measurements.

Contribution

It provides a comprehensive dataset of supernova light curves with enhanced calibration and systematic error analysis, aiding cosmological studies.

Findings

Achieved ~1% systematic error in photometric calibration.

Provided accurate classifications and redshifts for 213 supernovae.

Improved photometric calibration precision of the CTIO Blanco system.

Abstract

The ESSENCE survey discovered 213 Type Ia supernovae at redshifts 0.1 < z < 0.81 between 2002 and 2008. We present their R and I-band photometry, measured from images obtained using the MOSAIC II camera at the CTIO 4 m Blanco telescope, along with rapid-response spectroscopy for each object. We use our spectroscopic follow-up observations to determine an accurate, quantitative classification and a precise redshift. Through an extensive calibration program we have improved the precision of the CTIO Blanco natural photometric system. We use several empirical metrics to measure our internal photometric consistency and our absolute calibration of the survey. We assess the effect of various potential sources of systematic bias on our measured fluxes, and we estimate that the dominant term in the systematic error budget from the photometric calibration on our absolute fluxes is ~1%.