PS1-10afx AT z = 1.388: PAN-STARRS1 DISCOVERY OF A NEW TYPE OF SUPERLUMINOUS SUPERNOVA

Journal Article · Sat Apr 20 00:00:00 EDT 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/767/2/162· OSTI ID:22126879

Chornock, R.; Berger, E.; Milisavljevic, D.; Lunnan, R.; Foley, R. J.; Soderberg, A. M.; Challis, P.; Czekala, I.; Drout, M.; Fong, W.; Kirshner, R. P.; McLeod, B.; Marion, G. H.; Narayan, G. ^[1]; Rest, A. ^[2]; Smartt, S. J. ^[3]; Burgasser, A. J. ^[4]; Chomiuk, L. ^[5]; Huber, M. E. ^[6]; others, and

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1. Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)
2. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
3. Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, Belfast, BT7 1NN (United Kingdom)
4. Center for Astrophysics and Space Science, University of California San Diego, La Jolla, CA 92093 (United States)
5. Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)
6. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

We present the Pan-STARRS1 discovery of PS1-10afx, a unique hydrogen-deficient superluminous supernova (SLSN) at redshift z = 1.388. The light curve peaked at z{sub P1} = 21.7 mag, making PS1-10afx comparable to the most luminous known SNe, with M{sub u} = -22.3 mag. Our extensive optical and near-infrared observations indicate that the bolometric light curve of PS1-10afx rose on the unusually fast timescale of {approx}12 days to the extraordinary peak luminosity of 4.1 Multiplication-Sign 10{sup 44} erg s{sup -1} (M{sub bol} = -22.8 mag) and subsequently faded rapidly. Equally important, the spectral energy distribution is unusually red for an SLSN, with a color temperature of {approx}6800 K near maximum light, in contrast to previous hydrogen-poor SLSNe, which are bright in the ultraviolet (UV). The spectra more closely resemble those of a normal SN Ic than any known SLSN, with a photospheric velocity of {approx}11, 000 km s{sup -1} and evidence for line blanketing in the rest-frame UV. Despite the fast rise, these parameters imply a very large emitting radius ({approx}> 5 Multiplication-Sign 10{sup 15} cm). We demonstrate that no existing theoretical model can satisfactorily explain this combination of properties: (1) a nickel-powered light curve cannot match the combination of high peak luminosity with the fast timescale; (2) models powered by the spindown energy of a rapidly rotating magnetar predict significantly hotter and faster ejecta; and (3) models invoking shock breakout through a dense circumstellar medium cannot explain the observed spectra or color evolution. The host galaxy is well detected in pre-explosion imaging with a luminosity near L*, a star formation rate of {approx}15 M{sub Sun} yr{sup -1}, and is fairly massive ({approx}2 Multiplication-Sign 10{sup 10} M{sub Sun }), with a stellar population age of {approx}10{sup 8} yr, also in contrast to the young dwarf hosts of known hydrogen-poor SLSNe. PS1-10afx is distinct from known examples of SLSNe in its spectra, colors, light-curve shape, and host galaxy properties, suggesting that it resulted from a different channel than other hydrogen-poor SLSNe.

• OSTI ID: 22126879
• Journal Information: Astrophysical Journal, Vol. 767, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ENERGY SPECTRA
GALAXIES
HYDROGEN
LUMINOSITY
PEAKS
SUPERNOVAE