The Discovery of the Most Distant Known Type Ia Supernova at Redshift 1.914

• Published in: arXiv.org 2013-04
• Main Authors: Jones, David O, Rodney, Steven A, Riess, Adam G, Mobasher, Bahram, Dahlen, Tomas, McCully, Curtis, Frederiksen, Teddy F, Casertano, Stefano, Hjorth, Jens, Keeton, Charles R, Koekemoer, Anton, Louis-Gregory Strolger, Wiklind, Tommy G, Challis, Peter, Or Graur, Hayden, Brian, Patel, Brandon, Weiner, Benjamin J, Filippenko, Alexei V, Garnavich, Peter, Jha, Saurabh W, Kirshner, Robert P, Ferguson, Henry C, Grogin, Norman A, Kocevski, Dale
• Format: Article
• Language: English
• Subjects: Classification; Collapse; Cosmology; Field cameras; Hubble Space Telescope; Infrared cameras; Light curve; Photometry; Quantitative analysis; Red shift; Space telescopes; Supernovae
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1304.0768

We present the discovery of a Type Ia supernova (SN) at redshift \(z = 1.914\) from the CANDELS multi-cycle treasury program on the \textit{Hubble Space Telescope (HST)}. This SN was discovered in the infrared using the Wide-Field Camera 3, and it is the highest-redshift Type Ia SN yet observed. We classify this object as a SN\,Ia by comparing its light curve and spectrum with those of a large sample of Type Ia and core-collapse supernovae (SNe). Its apparent magnitude is consistent with that expected from the \(\Lambda\)CDM concordance cosmology. We discuss the use of spectral evidence for classification of \(z > 1.5\) SNe\,Ia using {\it HST} grism simulations, finding that spectral data alone can frequently rule out SNe\,II, but distinguishing between SNe\,Ia and SNe\,Ib/c can require prohibitively long exposures. In such cases, a quantitative analysis of the light curve may be necessary for classification. Our photometric and spectroscopic classification methods can aid the determination of SN rates and cosmological parameters from the full high-redshift CANDELS SN sample.