First Results from the La Silla-QUEST Supernova Survey and the Carnegie Supernova Project

TL;DR

This paper presents initial results from the La Silla-QUEST and Carnegie Supernova Project collaboration, showcasing the discovery and analysis of 31 low-redshift Type Ia supernovae with detailed light curves and a preliminary Hubble diagram.

Contribution

First combined survey results providing photometric light curves and analysis methods for low-redshift Type Ia supernovae, including initial Hubble diagram data.

Findings

Average measurement error of 4% for supernovae

Intrinsic spread of 14% in supernova brightness

Light curves analyzed with SALT 2.4 fitter

Abstract

The LaSilla/QUEST Variability Survey (LSQ) and the Carnegie Supernova Project (CSP II) are collaborating to discover and obtain photometric light curves for a large sample of low redshift (z < 0.1) Type Ia supernovae. The supernovae are discovered in the LSQ survey using the 1 m ESO Schmidt telescope at the La Silla Observatory with the 10 square degree QUEST camera. The follow-up photometric observations are carried out using the 1 m Swope telescope and the 2.5 m du Pont telescopes at the Las Campanas Observatory. This paper describes the survey, discusses the methods of analyzing the data and presents the light curves for the first 31 Type Ia supernovae obtained in the survey. The SALT 2.4 supernova light curve fitter was used to analyze the photometric data, and the Hubble diagram for this first sample is presented. The measurement errors for these supernovae averaged 4%, and their intrinsic spread was 14%.