* Astronomy

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RE: Super-luminous supernovae

Blobrana · L

Title: Double-humped Super-luminous Supernovae
Authors: D. Leahy, R. Ouyed

Super-luminous supernova (SLSN) are supernovae showing extreme properties in their light-curves: high peak luminosities (more than 10 times brighter than bright SN Ia), and long durations. Several mechanisms have been proposed for SLSN, such as pair instability SN of a massive progenitor, interaction of the ejecta with a massive circumstellar shell, and the dual-shock quark nova (dsQN) model. The dual-shock quark nova model is unique in that it predicts a normal SN event will be seen about 10 days prior to the main SLSN event. The dsQN model is described here and shown that it is consistent with the light curve of the one currently known double-humped SLSN, 2006oz.

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Title: Super-luminous supernovae at redshifts of 2.05 and 3.90
Authors: Jeff Cooke (Swinburne), Mark Sullivan (Oxford), Avishay Gal-Yam (Weizmann), Elizabeth J. Barton (UC Irvine), Raymond G. Carlberg (Toronto), Emma V. Ryan-Weber (Swinburne), Chuck Horst (San Diego State), Yuuki Omori (McGill), C. Gonzalo Diaz (Swinburne)

A rare class of 'super-luminous' supernovae that are about ten or more times more luminous at their peaks than other types of luminous supernovae has recently been found at low to intermediate redshifts. A small subset of these events have luminosities that evolve slowly and result in radiated energies of around 10^51 ergs or more. Therefore, they are likely examples of 'pair-instability' or 'pulsational pair-instability' supernovae with estimated progenitor masses of 100 - 250 times that of the Sun. These events are exceedingly rare at low redshift, but are expected to be more common at high redshift because the mass distribution of the earliest stars was probably skewed to high values. Here we report the detection of two super-luminous supernovae, at redshifts of 2.05 and 3.90, that have slowly evolving light curves. We estimate the rate of events at redshifts of 2 and 4 to be approximately ten times higher than the rate at low redshift. The extreme luminosities of super-luminous supernovae extend the redshift limit for supernova detection using present technology, previously 2.36, and provide a way of investigating the deaths of the first generation of stars to form after the Big Bang.

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Distant super-luminous supernovae found

Two 'super-luminous' supernovae - stellar explosions 10 to 100 times brighter than other supernova types - have been detected in the distant Universe.
The discovery, led by Swinburne University of Technology astrophysicist Dr Jeffrey Cooke, and reported online in Nature this week, sets a record for the most distant supernova yet detected.
Super-luminous supernovae were first discovered only a few years ago and are extremely rare in the nearby Universe.
The origins of super-luminous supernovae are not well understood, but a small subset of them are thought to occur when extremely massive stars, 150 to 250 times more massive than our Sun, undergo a nuclear explosion triggered by the conversion of photons into electron-positron pairs. This process is completely different compared to all other types of supernovae.
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