A team of researchers at the Kavli IPMU led by Robert Quimby has identified what may prove to be the first ever Type Ia supernova (SNIa) magnified by a strong gravitational lens.
In this work, the 'standard candle' property of Type Ia supernovae is used to directly measure the magnification due to gravitational lensing. This provides the first glimpse of the science that will soon come out of dark matter and dark energy studies derived from deep, wide-field imaging surveys. The supernova, named PS1-10afx, was discovered by the Panoramic Survey Telescope and Rapid Response System 1 (Pan-STARRS1).
PS1-10afx exploded over 9 billion years ago, which places it far further than typical Pan-STARRS1 discoveries. Based on this distance and its relatively bright appearance, the Pan-STARRS1 team concluded that PS1-10afx was intrinsically very luminous.
The inferred luminosity, about 100 billion times greater than our Sun, is comparable to members of a new, rare variety of superluminous supernovae (SLSNe), but that is where the similarities end.
SLSNe typically have blue colors, and their brightness changes relatively slowly with time. PS1-10afx on the other hand was rather red even after correcting for its redshift, and its brightness changed as fast as normal supernovae. There is no known physical model that can explain how a supernova could simultaneously be so luminous, so red, and so fast.
Soon after the findings were announced, Robert Quimby, a postdoctoral researcher at Kavli IPMU, independently analyzed the data. Quimby is an expert in SLSNe and has played a key role in their discovery. He quickly confirmed part, but not all of the conclusions.
PS1-10afx was indeed rather distinct from all known SLSNe, but the data struck Quimby as oddly familiar. He compared the features seen in the spectra of PS1-10afx to known supernova, and, surprisingly, found an excellent match. The spectra of PS1-10afx are almost identical to normal SNIa.
SNIa have a very useful property that has enabled cosmologists to chart the expansion of our Universe over the last several billion years: SNIa have strikingly similar peak luminosities that can be rendered even more standard by correcting for how quickly they brighten and fade (their "light curves").
This property allows astronomers to use SNIa as standard candles to measure distances, as was key to the discovery of the accelerating expansion of the Universe (2011 Nobel Prize in Physics).
Via Aso Galicia, RUBEN RODRIGUEZ AMADOR