A Type Ia Supernova at Redshift 1.55 in Hubble Space Telescope Infrared Observations from CANDELS

Understand

We report the discovery of a Type Ia supernova (SNIa) at redshift z=1.55 with the infrared detector of the Wide Field Camera 3 (WFC3-IR) on the Hubble Space Telescope (HST).

• This object was discovered in CANDELS imaging data of the Hubble Ultra Deep Field, and followed as part of the CANDELS+CLASH Supernova project, comprising the SN search components from those two HST multi-cycle treasury programs.
• This is the highest redshift SNIa with direct spectroscopic evidence for classification.
• It is also the first SN Ia at z>1 found and followed in the infrared, providing a full light curve in rest-frame optical bands.