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arXiv · 1404.6014

Detection of the Gravitational Lens Magnifying a Type Ia Supernova

Robert M. Quimby·Masamune Oguri·Anupreeta More·Surhud More·Takashi J. Moriya·Marcus C. Werner·Masayuki Tanaka·Gaston Folatelli·Melina C. Bersten·Keiichi Maeda·Ken'ichi Nomoto
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Abstract

Objects of known brightness, like Type Ia supernovae (SNIa), can be used to measure distances. If a massive object warps spacetime to form multiple images of a background SNIa, a direct test of cosmic expansion is also possible. However, these lensing events must first be distinguished from other rare phenomena. Recently, a supernova was found to shine much brighter than normal for its distance, which resulted in a debate: was it a new type of superluminous supernova or a normal SNIa magnified by a hidden gravitational lens? Here we report that a spectrum obtained after the supernova faded away shows the presence of a foreground galaxy--the first found to strongly magnify a SNIa. We discuss how more lensed SNIa may be found than previously predicted.

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Robert M. Quimby, Masamune Oguri, Anupreeta More, Surhud More, Takashi J. Moriya, Marcus C. Werner, Masayuki Tanaka, Gaston Folatelli, Melina C. Bersten, Keiichi Maeda, Ken'ichi Nomoto. 2014-04-24. Detection of the Gravitational Lens Magnifying a Type Ia Supernova. https://doi.org/10.1126/science.1250903

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