Abstract

We have begun a program to discover high-redshift supernovae ( z ≈ 0.2–0.6), and study them with follow-up photometry and spectroscopy. We report here our first discovery, a supernova at z = 0.458 (SN1992bi) and the ongoing analysis on several new supernova candidates found in a recent search (Dec 93 – March 94). The photometry for SN1992bi closely matches the lightcurve calculated for its redshift from the template of well-observed nearby Type la supernovae giving a best fit value for the deceleration parameter: q o = 0.1 ± 0.3 (±0.55) (with Λ = 0), where the first uncertainty is due to the photometry of the distant supernova and the second reflects the estimated intrinsic width of the Type la absolute magnitude distribution based on nearby supernovae. If there is significant host galaxy extinction then q o would be larger than this best fit value. We describe the main sources of measurement error inherent in such a measurement of qo , and ways to reduce these errors.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.