TY - JOUR
T1 - The subluminous supernova 2007qd
T2 - A missing link in a family of low-luminosity Type Ia supernovae
AU - McClelland, Colin M.
AU - Garnavich, Peter M.
AU - Galbany, Lluís
AU - Miquel, Ramon
AU - Foley, Ryan J.
AU - Filippenko, Alexei V.
AU - Bassett, Bruce
AU - Wheeler, J. Craig
AU - Goobar, Ariel
AU - Jha, Saurabh W.
AU - Sako, Masao
AU - Frieman, Joshua A.
AU - Sollerman, Jesper
AU - Vinko, Jozsef
AU - Schneider, Donald P.
PY - 2010/9/1
Y1 - 2010/9/1
N2 - We present multi-band photometry and multi-epoch spectroscopy of the peculiar Type Ia supernova (SN Ia) 2007qd, discovered by the SDSS-II Supernova Survey. It possesses physical properties intermediate to those of the peculiar SN 2002cx and the extremely low-luminosity SN 2008ha. Optical photometry indicates that it had an extraordinarily fast rise time of ≲10 days and a peak absolute B magnitude of -15.4 ± 0.2 at most, making it one of the most subluminous SN Ia ever observed. Follow-up spectroscopy of SN 2007qd near maximum brightness unambiguously shows the presence of intermediate-mass elements which are likely caused by carbon/oxygen nuclear burning. Near maximum brightness, SN 2007qd had a photospheric velocity of only 2800 km s -1, similar to that of SN 2008ha but about 4000 and 7000 km s -1 less than that of SN 2002cx and normal SN Ia, respectively. We show that the peak luminosities of SN 2002cx like objects are highly correlated with both their light-curve stretch and photospheric velocities. Its strong apparent connection to other SN 2002cx like events suggests that SN 2007qd is also a pure deflagration of a white dwarf, although other mechanisms cannot be ruled out. It may be a critical link between SN 2008ha and the other members of the SN 2002cx like class of objects.
AB - We present multi-band photometry and multi-epoch spectroscopy of the peculiar Type Ia supernova (SN Ia) 2007qd, discovered by the SDSS-II Supernova Survey. It possesses physical properties intermediate to those of the peculiar SN 2002cx and the extremely low-luminosity SN 2008ha. Optical photometry indicates that it had an extraordinarily fast rise time of ≲10 days and a peak absolute B magnitude of -15.4 ± 0.2 at most, making it one of the most subluminous SN Ia ever observed. Follow-up spectroscopy of SN 2007qd near maximum brightness unambiguously shows the presence of intermediate-mass elements which are likely caused by carbon/oxygen nuclear burning. Near maximum brightness, SN 2007qd had a photospheric velocity of only 2800 km s -1, similar to that of SN 2008ha but about 4000 and 7000 km s -1 less than that of SN 2002cx and normal SN Ia, respectively. We show that the peak luminosities of SN 2002cx like objects are highly correlated with both their light-curve stretch and photospheric velocities. Its strong apparent connection to other SN 2002cx like events suggests that SN 2007qd is also a pure deflagration of a white dwarf, although other mechanisms cannot be ruled out. It may be a critical link between SN 2008ha and the other members of the SN 2002cx like class of objects.
UR - http://www.scopus.com/inward/record.url?scp=78049370125&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=78049370125&partnerID=8YFLogxK
U2 - 10.1088/0004-637X/720/1/704
DO - 10.1088/0004-637X/720/1/704
M3 - Article
AN - SCOPUS:78049370125
SN - 0004-637X
VL - 720
SP - 704
EP - 716
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
ER -