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Title: Measurement of Omega_m, Omega_Lambda from a blind analysis of TypeIa supernovae with CMAGIC: Using color information to verify theacceleration of the Universe

Abstract

We present measurements of {Omega}{sub m} and {Omega}{sub {Lambda}} from a blind analysis of 21 high redshift supernovae using a new technique (CMAGIC) for fitting the multicolor lightcurves of Type Ia supernovae, first introduced in Wang et al. (2003). CMAGIC takes advantage of the remarkably simple behavior of Type Ia supernovae on color-magnitude diagrams, and has several advantages over current techniques based on maximum magnitudes. Among these are a reduced sensitivity to host galaxy dust extinction, a shallower luminosity-width relation, and the relative simplicity of the fitting procedure. This allows us to provide a cross check of previous supernova cosmology results, despite the fact that current data sets were not observed in a manner optimized for CMAGIC. We describe the details of our novel blindness procedure, which is designed to prevent experimenter bias. The data are broadly consistent with the picture of an accelerating Universe, and agree with a at Universe within 1.7{sigma}, including systematics. We also compare the CMAGIC results directly with those of a maximum magnitude fit to the same SNe, finding that CMAGIC favors more acceleration at the 1.6{sigma} level, including systematics and the correlation between the two measurements. A fit for w assuming a at Universemore » yields a value which is consistent with a cosmological constant within 1.2{sigma}.« less

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »; ; ; ; ; ; ; ; ; « less
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE Director. Office of Science. Office of AdvancedScientific Computing Research. Office of High Energy Physics
OSTI Identifier:
891825
Report Number(s):
LBNL-59954
R&D Project: PSUOPS; BnR: KA1301020; TRN: US0605497
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: The Astrophysical Journal; Journal Volume: 644; Journal Issue: 1; Related Information: Journal Publication Date: 06/10/2006
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCELERATION; COLOR; COSMOLOGICAL CONSTANT; COSMOLOGY; DUSTS; SENSITIVITY; SUPERNOVAE; UNIVERSE; Supernovae Cosmology

Citation Formats

Conley, A., Goldhaber, G., Wang, L., Aldering, G., Amanullah, R., Commins, E.D., Fadeyev, V., Folatelli, G., Garavini, G., Gibbons, R., Goobar, A., Groom, D.E., Hook, I., Howell, D.A., Kim, A.G., Knop, R.A., Kowalski, M., Kuznetsova, N., Lidman, C., Nobili, S., Nugent, P.E., Pain,R., Perlmutter, S., Smith, E., Spadafora, A.L., Stanishev, V., Strovink,M., Thomas, R.C., and Wood-Vasey, W.M. Measurement of Omega_m, Omega_Lambda from a blind analysis of TypeIa supernovae with CMAGIC: Using color information to verify theacceleration of the Universe. United States: N. p., 2006. Web. doi:10.1086/503533.
Conley, A., Goldhaber, G., Wang, L., Aldering, G., Amanullah, R., Commins, E.D., Fadeyev, V., Folatelli, G., Garavini, G., Gibbons, R., Goobar, A., Groom, D.E., Hook, I., Howell, D.A., Kim, A.G., Knop, R.A., Kowalski, M., Kuznetsova, N., Lidman, C., Nobili, S., Nugent, P.E., Pain,R., Perlmutter, S., Smith, E., Spadafora, A.L., Stanishev, V., Strovink,M., Thomas, R.C., & Wood-Vasey, W.M. Measurement of Omega_m, Omega_Lambda from a blind analysis of TypeIa supernovae with CMAGIC: Using color information to verify theacceleration of the Universe. United States. doi:10.1086/503533.
Conley, A., Goldhaber, G., Wang, L., Aldering, G., Amanullah, R., Commins, E.D., Fadeyev, V., Folatelli, G., Garavini, G., Gibbons, R., Goobar, A., Groom, D.E., Hook, I., Howell, D.A., Kim, A.G., Knop, R.A., Kowalski, M., Kuznetsova, N., Lidman, C., Nobili, S., Nugent, P.E., Pain,R., Perlmutter, S., Smith, E., Spadafora, A.L., Stanishev, V., Strovink,M., Thomas, R.C., and Wood-Vasey, W.M. Tue . "Measurement of Omega_m, Omega_Lambda from a blind analysis of TypeIa supernovae with CMAGIC: Using color information to verify theacceleration of the Universe". United States. doi:10.1086/503533. https://www.osti.gov/servlets/purl/891825.
@article{osti_891825,
title = {Measurement of Omega_m, Omega_Lambda from a blind analysis of TypeIa supernovae with CMAGIC: Using color information to verify theacceleration of the Universe},
author = {Conley, A. and Goldhaber, G. and Wang, L. and Aldering, G. and Amanullah, R. and Commins, E.D. and Fadeyev, V. and Folatelli, G. and Garavini, G. and Gibbons, R. and Goobar, A. and Groom, D.E. and Hook, I. and Howell, D.A. and Kim, A.G. and Knop, R.A. and Kowalski, M. and Kuznetsova, N. and Lidman, C. and Nobili, S. and Nugent, P.E. and Pain,R. and Perlmutter, S. and Smith, E. and Spadafora, A.L. and Stanishev, V. and Strovink,M. and Thomas, R.C. and Wood-Vasey, W.M.},
abstractNote = {We present measurements of {Omega}{sub m} and {Omega}{sub {Lambda}} from a blind analysis of 21 high redshift supernovae using a new technique (CMAGIC) for fitting the multicolor lightcurves of Type Ia supernovae, first introduced in Wang et al. (2003). CMAGIC takes advantage of the remarkably simple behavior of Type Ia supernovae on color-magnitude diagrams, and has several advantages over current techniques based on maximum magnitudes. Among these are a reduced sensitivity to host galaxy dust extinction, a shallower luminosity-width relation, and the relative simplicity of the fitting procedure. This allows us to provide a cross check of previous supernova cosmology results, despite the fact that current data sets were not observed in a manner optimized for CMAGIC. We describe the details of our novel blindness procedure, which is designed to prevent experimenter bias. The data are broadly consistent with the picture of an accelerating Universe, and agree with a at Universe within 1.7{sigma}, including systematics. We also compare the CMAGIC results directly with those of a maximum magnitude fit to the same SNe, finding that CMAGIC favors more acceleration at the 1.6{sigma} level, including systematics and the correlation between the two measurements. A fit for w assuming a at Universe yields a value which is consistent with a cosmological constant within 1.2{sigma}.},
doi = {10.1086/503533},
journal = {The Astrophysical Journal},
number = 1,
volume = 644,
place = {United States},
year = {Tue Feb 21 00:00:00 EST 2006},
month = {Tue Feb 21 00:00:00 EST 2006}
}
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