TY - JOUR
T1 - Cosmology with photometrically-classified Type Ia Supernovae from the SDSS-II Supernova Survey
AU - Campbell, Heather C.
AU - D’Andrea, Chris B.
AU - Nichol, Robert C.
AU - Sako, Masao
AU - Smith, Mathew
AU - Lampeitl, Hubert
AU - Olmstead, Matthew D.
AU - Bassett, Bruce A.
AU - Biswas, Rahul
AU - Brown, Peter J.
AU - Cinabro, David
AU - Dawson, Kyle S.
AU - Dilday, Benjamin
AU - Foley, Ryan J.
AU - Frieman, Joshua A.
AU - Garnavich, Peter M.
AU - Hlozek, Renee
AU - Jha, Saurabh W.
AU - Kuhlmann, Steve
AU - Kunz, Martin
AU - Marriner, John P.
AU - Miquel, Ramon
AU - Richmond, Michael W.
AU - Riess, Adam G.
AU - Schneider, Donald P.
AU - Sollerman, Jesper
AU - Taylor, Matt
AU - Zhao, Gong-Bo
PY - 2013/2/1
Y1 - 2013/2/1
N2 - We present the cosmological analysis of 752 photometrically classified Type Ia Supernovae (SNe Ia) obtained from the full Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey, supplemented with host-galaxy spectroscopy from the SDSS-III Baryon Oscillation Spectroscopic Survey. Our photometric-classification method is based on the SN classification technique of Sako et al., aided by host-galaxy redshifts (0.05 < z < 0.55). SuperNova ANAlysis simulations of our methodology estimate that we have an SN Ia classification efficiency of 70.8%, with only 3.9% contamination from core-collapse (non-Ia) SNe. We demonstrate that this level of contamination has no effect on our cosmological constraints. We quantify and correct for our selection effects (e.g., Malmquist bias) using simulations. When fitting to a flat ΛCDM cosmological model, we find that our photometric sample alone gives Ω m = 0.24+0.07 –0.05 (statistical errors only). If we relax the constraint on flatness, then our sample provides competitive joint statistical constraints on Ω m and ΩΛ, comparable to those derived from the spectroscopically confirmed Three-year Supernova Legacy Survey (SNLS3). Using only our data, the statistics-only result favors an accelerating universe at 99.96% confidence. Assuming a constant wCDM cosmological model, and combining with H 0, cosmic microwave background, and luminous red galaxy data, we obtain w = –0.96+0.10 –0.10, Ω m = 0.29+0.02 –0.02, and Ω k = 0.00+0.03 –0.02 (statistical errors only), which is competitive with similar spectroscopically confirmed SNe Ia analyses. Overall this comparison is reassuring, considering the lower redshift leverage of the SDSS-II SN sample (z < 0.55) and the lack of spectroscopic confirmation used herein. These results demonstrate the potential of photometrically classified SN Ia samples in improving cosmological constraints.
AB - We present the cosmological analysis of 752 photometrically classified Type Ia Supernovae (SNe Ia) obtained from the full Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey, supplemented with host-galaxy spectroscopy from the SDSS-III Baryon Oscillation Spectroscopic Survey. Our photometric-classification method is based on the SN classification technique of Sako et al., aided by host-galaxy redshifts (0.05 < z < 0.55). SuperNova ANAlysis simulations of our methodology estimate that we have an SN Ia classification efficiency of 70.8%, with only 3.9% contamination from core-collapse (non-Ia) SNe. We demonstrate that this level of contamination has no effect on our cosmological constraints. We quantify and correct for our selection effects (e.g., Malmquist bias) using simulations. When fitting to a flat ΛCDM cosmological model, we find that our photometric sample alone gives Ω m = 0.24+0.07 –0.05 (statistical errors only). If we relax the constraint on flatness, then our sample provides competitive joint statistical constraints on Ω m and ΩΛ, comparable to those derived from the spectroscopically confirmed Three-year Supernova Legacy Survey (SNLS3). Using only our data, the statistics-only result favors an accelerating universe at 99.96% confidence. Assuming a constant wCDM cosmological model, and combining with H 0, cosmic microwave background, and luminous red galaxy data, we obtain w = –0.96+0.10 –0.10, Ω m = 0.29+0.02 –0.02, and Ω k = 0.00+0.03 –0.02 (statistical errors only), which is competitive with similar spectroscopically confirmed SNe Ia analyses. Overall this comparison is reassuring, considering the lower redshift leverage of the SDSS-II SN sample (z < 0.55) and the lack of spectroscopic confirmation used herein. These results demonstrate the potential of photometrically classified SN Ia samples in improving cosmological constraints.
U2 - 10.1088/0004-637X/763/2/88
DO - 10.1088/0004-637X/763/2/88
M3 - Article
SN - 0004-637X
VL - 763
SP - 88
JO - The Astrophysical Journal
JF - The Astrophysical Journal
IS - 2
ER -