Precision Measurement of The Most Distant Spectroscopically Confirmed Supernova Ia with the Hubble Space Telescope

Abstract

We report the discovery of a redshift 1.71 supernova in the GOODS North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from the host or neighboring galaxies. Although the rest frame sampled range is too blue to include any Si ii line, a principal component analysis allows us to confirm it as a Type Ia supernova with 92% confidence. A recent serendipitous archival HST WFC3 grism spectrum contributed a key element of the confirmation by giving a host-galaxy redshift of 1.713 +/- 0.007. In addition to being the most distant SN Ia with spectroscopic confirmation, this is the most distant Ia with a precision color measurement. We present the ACS WFC and NICMOS 2 photometry and ACS and WFC3 spectroscopy. Our derived supernova distance is in agreement with the prediction of LambdaCDM.

13 pages, 6 figures, published in ApJ with updated analysis

References in corpus (7)

• New Hubble Space Telescope Discoveries of Type Ia Supernovae at z > 1: Narrowing Constraints on the Early Behavior of Dark Energy
• Improved Cosmological Constraints from New, Old and Combined Supernova Datasets
• Spectra and Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
• CfA3: 185 Type Ia Supernova Light Curves from the CfA
• SN 2006jc: A Wolf-Rayet Star Exploding in a Dense He-Rich Circumstellar Medium
• SN 2005cs in M51 II. Complete Evolution in the Optical and the Near-Infrared
• Ultraviolet Spectroscopy of Supernovae: The First Two Years of Swift Observations