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Title: Observational Constraints on the Nature of the Dark Energy: First Cosmological Results From the ESSENCE Supernova Survey

Abstract

We present constraints on the dark energy equation-of-state parameter, w = P/({rho}c{sup 2}), using 60 Type Ia supernovae (SNe Ia) from the ESSENCE supernova survey. We derive a set of constraints on the nature of the dark energy assuming a flat Universe. By including constraints on ({Omega}{sub M}, w) from baryon acoustic oscillations, we obtain a value for a static equation-of-state parameter w = -1.05{sub -0.12}{sup +0.13} (stat 1{sigma}) {+-} 0.13 (sys) and {Omega}{sub M} = 0.274{sub -0.020}{sup +0.033} (stat 1{sigma}) with a best-fit {chi}{sup 2}/DoF of 0.96. These results are consistent with those reported by the Super-Nova Legacy Survey in a similar program measuring supernova distances and redshifts. We evaluate sources of systematic error that afflict supernova observations and present Monte Carlo simulations that explore these effects. Currently, the largest systematic currently with the potential to affect our measurements is the treatment of extinction due to dust in the supernova host galaxies. Combining our set of ESSENCE SNe Ia with the SuperNova Legacy Survey SNe Ia, we obtain a joint constraint of w = -1.07{sub -0.09}{sup +0.09} (stat 1{sigma}) {+-} 0.13 (sys), {Omega}{sub M} = 0.267{sub -0.018}{sup +0.028} (stat 1{sigma}) with a best-fit {chi}{sup 2}/DoF of 0.91. The currentmore » SNe Ia data are fully consistent with a cosmological constant.« less

Authors:
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Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
896931
Report Number(s):
SLAC-PUB-12281
astro-ph/0701041; TRN: US200705%%76
DOE Contract Number:
AC02-76SF00515
Resource Type:
Journal Article
Resource Relation:
Journal Name: Submitted to Astrophys.J.
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACOUSTICS; BARYONS; COSMOLOGICAL CONSTANT; DUSTS; GALAXIES; OSCILLATIONS; SUPERNOVAE; UNIVERSE; Astrophysics,ASTRO

Citation Formats

Wood-Vasey, W.Michael, Miknaitis, G., Stubbs, C.W., Jha, S., Riess, A.G., Garnavich, P.M., Kirshner, R.P., Aguilera, C., Becker, A.C., Blackman, J.W., Blondin, S., Challis, P., Clocchiatti, A., Conley, A., Covarrubias, R., Davis, T.M., Filippenko, A.V., Foley, R.J., Garg, A., Hicken, M., Krisciunas, K., and /Harvard-Smithsonian Ctr. Astrophys. /Fermilab /Harvard U. /UC, Berkeley, Astron. Dept. /KIPAC, Menlo Park /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Notre Dame U. /Cerro-Tololo InterAmerican Obs. /Washington U., Seattle, Astron. Dept. /Res. Sch. Astron. Astrophys., Weston Creek /Chile U., Catolica /Toronto U., Astron. Dept. /Bohr Inst. /Stockholm U. /Texas A-M /European Southern Observ. /NOAO, Tucson /Ohio State U., Dept. Astron. /Inst. Astron., Honolulu. Observational Constraints on the Nature of the Dark Energy: First Cosmological Results From the ESSENCE Supernova Survey. United States: N. p., 2007. Web. doi:10.1086/518642.
Wood-Vasey, W.Michael, Miknaitis, G., Stubbs, C.W., Jha, S., Riess, A.G., Garnavich, P.M., Kirshner, R.P., Aguilera, C., Becker, A.C., Blackman, J.W., Blondin, S., Challis, P., Clocchiatti, A., Conley, A., Covarrubias, R., Davis, T.M., Filippenko, A.V., Foley, R.J., Garg, A., Hicken, M., Krisciunas, K., & /Harvard-Smithsonian Ctr. Astrophys. /Fermilab /Harvard U. /UC, Berkeley, Astron. Dept. /KIPAC, Menlo Park /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Notre Dame U. /Cerro-Tololo InterAmerican Obs. /Washington U., Seattle, Astron. Dept. /Res. Sch. Astron. Astrophys., Weston Creek /Chile U., Catolica /Toronto U., Astron. Dept. /Bohr Inst. /Stockholm U. /Texas A-M /European Southern Observ. /NOAO, Tucson /Ohio State U., Dept. Astron. /Inst. Astron., Honolulu. Observational Constraints on the Nature of the Dark Energy: First Cosmological Results From the ESSENCE Supernova Survey. United States. doi:10.1086/518642.
Wood-Vasey, W.Michael, Miknaitis, G., Stubbs, C.W., Jha, S., Riess, A.G., Garnavich, P.M., Kirshner, R.P., Aguilera, C., Becker, A.C., Blackman, J.W., Blondin, S., Challis, P., Clocchiatti, A., Conley, A., Covarrubias, R., Davis, T.M., Filippenko, A.V., Foley, R.J., Garg, A., Hicken, M., Krisciunas, K., and /Harvard-Smithsonian Ctr. Astrophys. /Fermilab /Harvard U. /UC, Berkeley, Astron. Dept. /KIPAC, Menlo Park /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Notre Dame U. /Cerro-Tololo InterAmerican Obs. /Washington U., Seattle, Astron. Dept. /Res. Sch. Astron. Astrophys., Weston Creek /Chile U., Catolica /Toronto U., Astron. Dept. /Bohr Inst. /Stockholm U. /Texas A-M /European Southern Observ. /NOAO, Tucson /Ohio State U., Dept. Astron. /Inst. Astron., Honolulu. Fri . "Observational Constraints on the Nature of the Dark Energy: First Cosmological Results From the ESSENCE Supernova Survey". United States. doi:10.1086/518642. https://www.osti.gov/servlets/purl/896931.
@article{osti_896931,
title = {Observational Constraints on the Nature of the Dark Energy: First Cosmological Results From the ESSENCE Supernova Survey},
author = {Wood-Vasey, W.Michael and Miknaitis, G. and Stubbs, C.W. and Jha, S. and Riess, A.G. and Garnavich, P.M. and Kirshner, R.P. and Aguilera, C. and Becker, A.C. and Blackman, J.W. and Blondin, S. and Challis, P. and Clocchiatti, A. and Conley, A. and Covarrubias, R. and Davis, T.M. and Filippenko, A.V. and Foley, R.J. and Garg, A. and Hicken, M. and Krisciunas, K. and /Harvard-Smithsonian Ctr. Astrophys. /Fermilab /Harvard U. /UC, Berkeley, Astron. Dept. /KIPAC, Menlo Park /Baltimore, Space Telescope Sci. /Johns Hopkins U. /Notre Dame U. /Cerro-Tololo InterAmerican Obs. /Washington U., Seattle, Astron. Dept. /Res. Sch. Astron. Astrophys., Weston Creek /Chile U., Catolica /Toronto U., Astron. Dept. /Bohr Inst. /Stockholm U. /Texas A-M /European Southern Observ. /NOAO, Tucson /Ohio State U., Dept. Astron. /Inst. Astron., Honolulu},
abstractNote = {We present constraints on the dark energy equation-of-state parameter, w = P/({rho}c{sup 2}), using 60 Type Ia supernovae (SNe Ia) from the ESSENCE supernova survey. We derive a set of constraints on the nature of the dark energy assuming a flat Universe. By including constraints on ({Omega}{sub M}, w) from baryon acoustic oscillations, we obtain a value for a static equation-of-state parameter w = -1.05{sub -0.12}{sup +0.13} (stat 1{sigma}) {+-} 0.13 (sys) and {Omega}{sub M} = 0.274{sub -0.020}{sup +0.033} (stat 1{sigma}) with a best-fit {chi}{sup 2}/DoF of 0.96. These results are consistent with those reported by the Super-Nova Legacy Survey in a similar program measuring supernova distances and redshifts. We evaluate sources of systematic error that afflict supernova observations and present Monte Carlo simulations that explore these effects. Currently, the largest systematic currently with the potential to affect our measurements is the treatment of extinction due to dust in the supernova host galaxies. Combining our set of ESSENCE SNe Ia with the SuperNova Legacy Survey SNe Ia, we obtain a joint constraint of w = -1.07{sub -0.09}{sup +0.09} (stat 1{sigma}) {+-} 0.13 (sys), {Omega}{sub M} = 0.267{sub -0.018}{sup +0.028} (stat 1{sigma}) with a best-fit {chi}{sup 2}/DoF of 0.91. The current SNe Ia data are fully consistent with a cosmological constant.},
doi = {10.1086/518642},
journal = {Submitted to Astrophys.J.},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 05 00:00:00 EST 2007},
month = {Fri Jan 05 00:00:00 EST 2007}
}
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