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Y C Pan - One of the best experts on this subject based on the ideXlab platform.
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measuring dark energy properties with photometrically classified pan starrs supernovae ii Cosmological Parameters
The Astrophysical Journal, 2018Co-Authors: D O Jones, D Scolnic, Adam G Riess, A Rest, Robert P Kirshner, Edo Berger, R Kessler, Y C PanAbstract:We use 1169 Pan-STARRS supernovae (SNe) and 195 low-z (z < 0.1) SNe Ia to measure Cosmological Parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can be used to infer unbiased Cosmological Parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with cosmic microwave background (CMB) constraints from Planck, we measure the dark energy equation-of-state parameter w to be −0.989 ± 0.057 (stat+sys). If w evolves with redshift as w(a) = w 0 + w a (1 − a), we find w 0 = −0.912 ± 0.149 and w a = −0.513 ± 0.826. These results are consistent with Cosmological Parameters from the Joint Light-curve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a w differing by more than 2% from the baseline measurement. The systematic uncertainty on w due to marginalizing over CC SN contamination, ${\sigma }_{w}^{\mathrm{CC}}=0.012$, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6σ) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-z analyses. Our data provide one of the best current constraints on w, demonstrating that samples with ~5% CC SN contamination can give competitive Cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
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measuring dark energy properties with photometrically classified pan starrs supernovae ii Cosmological Parameters
arXiv: Cosmology and Nongalactic Astrophysics, 2017Co-Authors: D O Jones, D Scolnic, Adam G Riess, A Rest, Robert P Kirshner, Edo Berger, R Kessler, Y C PanAbstract:We use 1169 Pan-STARRS supernovae (SNe) and 195 low-$z$ ($z < 0.1$) SNe Ia to measure Cosmological Parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper (I) we demonstrated that photometrically classified SNe can be used to infer unbiased Cosmological Parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with Cosmic Microwave Background (CMB) constraints from Planck, we measure the dark energy equation of state parameter $w$ to be -0.989$\pm$0.057 (stat$+$sys). If $w$ evolves with redshift as $w(a) = w_0 + w_a(1-a)$, we find $w_0 = -0.912 \pm 0.149$ and $w_a =$ -0.513$\pm$0.826. These results are consistent with Cosmological Parameters from the Joint Lightcurve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a $w$ differing by more than 2% from the baseline measurement. The systematic uncertainty on $w$ due to marginalizing over CC SN contamination, $\sigma_w^{\textrm{CC}} = 0.012$, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6$\sigma$) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-$z$ analyses. Our data provide one of the best current constraints on $w$, demonstrating that samples with $\sim$5% CC SN contamination can give competitive Cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
A Rest - One of the best experts on this subject based on the ideXlab platform.
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measuring dark energy properties with photometrically classified pan starrs supernovae ii Cosmological Parameters
The Astrophysical Journal, 2018Co-Authors: D O Jones, D Scolnic, Adam G Riess, A Rest, Robert P Kirshner, Edo Berger, R Kessler, Y C PanAbstract:We use 1169 Pan-STARRS supernovae (SNe) and 195 low-z (z < 0.1) SNe Ia to measure Cosmological Parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can be used to infer unbiased Cosmological Parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with cosmic microwave background (CMB) constraints from Planck, we measure the dark energy equation-of-state parameter w to be −0.989 ± 0.057 (stat+sys). If w evolves with redshift as w(a) = w 0 + w a (1 − a), we find w 0 = −0.912 ± 0.149 and w a = −0.513 ± 0.826. These results are consistent with Cosmological Parameters from the Joint Light-curve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a w differing by more than 2% from the baseline measurement. The systematic uncertainty on w due to marginalizing over CC SN contamination, ${\sigma }_{w}^{\mathrm{CC}}=0.012$, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6σ) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-z analyses. Our data provide one of the best current constraints on w, demonstrating that samples with ~5% CC SN contamination can give competitive Cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
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measuring dark energy properties with photometrically classified pan starrs supernovae ii Cosmological Parameters
arXiv: Cosmology and Nongalactic Astrophysics, 2017Co-Authors: D O Jones, D Scolnic, Adam G Riess, A Rest, Robert P Kirshner, Edo Berger, R Kessler, Y C PanAbstract:We use 1169 Pan-STARRS supernovae (SNe) and 195 low-$z$ ($z < 0.1$) SNe Ia to measure Cosmological Parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper (I) we demonstrated that photometrically classified SNe can be used to infer unbiased Cosmological Parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with Cosmic Microwave Background (CMB) constraints from Planck, we measure the dark energy equation of state parameter $w$ to be -0.989$\pm$0.057 (stat$+$sys). If $w$ evolves with redshift as $w(a) = w_0 + w_a(1-a)$, we find $w_0 = -0.912 \pm 0.149$ and $w_a =$ -0.513$\pm$0.826. These results are consistent with Cosmological Parameters from the Joint Lightcurve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a $w$ differing by more than 2% from the baseline measurement. The systematic uncertainty on $w$ due to marginalizing over CC SN contamination, $\sigma_w^{\textrm{CC}} = 0.012$, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6$\sigma$) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-$z$ analyses. Our data provide one of the best current constraints on $w$, demonstrating that samples with $\sim$5% CC SN contamination can give competitive Cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
Adam G Riess - One of the best experts on this subject based on the ideXlab platform.
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measuring dark energy properties with photometrically classified pan starrs supernovae ii Cosmological Parameters
The Astrophysical Journal, 2018Co-Authors: D O Jones, D Scolnic, Adam G Riess, A Rest, Robert P Kirshner, Edo Berger, R Kessler, Y C PanAbstract:We use 1169 Pan-STARRS supernovae (SNe) and 195 low-z (z < 0.1) SNe Ia to measure Cosmological Parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can be used to infer unbiased Cosmological Parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with cosmic microwave background (CMB) constraints from Planck, we measure the dark energy equation-of-state parameter w to be −0.989 ± 0.057 (stat+sys). If w evolves with redshift as w(a) = w 0 + w a (1 − a), we find w 0 = −0.912 ± 0.149 and w a = −0.513 ± 0.826. These results are consistent with Cosmological Parameters from the Joint Light-curve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a w differing by more than 2% from the baseline measurement. The systematic uncertainty on w due to marginalizing over CC SN contamination, ${\sigma }_{w}^{\mathrm{CC}}=0.012$, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6σ) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-z analyses. Our data provide one of the best current constraints on w, demonstrating that samples with ~5% CC SN contamination can give competitive Cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
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measuring dark energy properties with photometrically classified pan starrs supernovae ii Cosmological Parameters
arXiv: Cosmology and Nongalactic Astrophysics, 2017Co-Authors: D O Jones, D Scolnic, Adam G Riess, A Rest, Robert P Kirshner, Edo Berger, R Kessler, Y C PanAbstract:We use 1169 Pan-STARRS supernovae (SNe) and 195 low-$z$ ($z < 0.1$) SNe Ia to measure Cosmological Parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper (I) we demonstrated that photometrically classified SNe can be used to infer unbiased Cosmological Parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with Cosmic Microwave Background (CMB) constraints from Planck, we measure the dark energy equation of state parameter $w$ to be -0.989$\pm$0.057 (stat$+$sys). If $w$ evolves with redshift as $w(a) = w_0 + w_a(1-a)$, we find $w_0 = -0.912 \pm 0.149$ and $w_a =$ -0.513$\pm$0.826. These results are consistent with Cosmological Parameters from the Joint Lightcurve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a $w$ differing by more than 2% from the baseline measurement. The systematic uncertainty on $w$ due to marginalizing over CC SN contamination, $\sigma_w^{\textrm{CC}} = 0.012$, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6$\sigma$) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-$z$ analyses. Our data provide one of the best current constraints on $w$, demonstrating that samples with $\sim$5% CC SN contamination can give competitive Cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
D O Jones - One of the best experts on this subject based on the ideXlab platform.
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measuring dark energy properties with photometrically classified pan starrs supernovae ii Cosmological Parameters
The Astrophysical Journal, 2018Co-Authors: D O Jones, D Scolnic, Adam G Riess, A Rest, Robert P Kirshner, Edo Berger, R Kessler, Y C PanAbstract:We use 1169 Pan-STARRS supernovae (SNe) and 195 low-z (z < 0.1) SNe Ia to measure Cosmological Parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can be used to infer unbiased Cosmological Parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with cosmic microwave background (CMB) constraints from Planck, we measure the dark energy equation-of-state parameter w to be −0.989 ± 0.057 (stat+sys). If w evolves with redshift as w(a) = w 0 + w a (1 − a), we find w 0 = −0.912 ± 0.149 and w a = −0.513 ± 0.826. These results are consistent with Cosmological Parameters from the Joint Light-curve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a w differing by more than 2% from the baseline measurement. The systematic uncertainty on w due to marginalizing over CC SN contamination, ${\sigma }_{w}^{\mathrm{CC}}=0.012$, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6σ) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-z analyses. Our data provide one of the best current constraints on w, demonstrating that samples with ~5% CC SN contamination can give competitive Cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
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measuring dark energy properties with photometrically classified pan starrs supernovae ii Cosmological Parameters
arXiv: Cosmology and Nongalactic Astrophysics, 2017Co-Authors: D O Jones, D Scolnic, Adam G Riess, A Rest, Robert P Kirshner, Edo Berger, R Kessler, Y C PanAbstract:We use 1169 Pan-STARRS supernovae (SNe) and 195 low-$z$ ($z < 0.1$) SNe Ia to measure Cosmological Parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper (I) we demonstrated that photometrically classified SNe can be used to infer unbiased Cosmological Parameters by using a Bayesian methodology that marginalizes over core-collapse (CC) SN contamination. Our sample contains nearly twice as many SNe as the largest previous SN Ia compilation. Combining SNe with Cosmic Microwave Background (CMB) constraints from Planck, we measure the dark energy equation of state parameter $w$ to be -0.989$\pm$0.057 (stat$+$sys). If $w$ evolves with redshift as $w(a) = w_0 + w_a(1-a)$, we find $w_0 = -0.912 \pm 0.149$ and $w_a =$ -0.513$\pm$0.826. These results are consistent with Cosmological Parameters from the Joint Lightcurve Analysis and the Pantheon sample. We try four different photometric classification priors for Pan-STARRS SNe and two alternate ways of modeling CC SN contamination, finding that no variant gives a $w$ differing by more than 2% from the baseline measurement. The systematic uncertainty on $w$ due to marginalizing over CC SN contamination, $\sigma_w^{\textrm{CC}} = 0.012$, is the third-smallest source of systematic uncertainty in this work. We find limited (1.6$\sigma$) evidence for evolution of the SN color-luminosity relation with redshift, a possible systematic that could constitute a significant uncertainty in future high-$z$ analyses. Our data provide one of the best current constraints on $w$, demonstrating that samples with $\sim$5% CC SN contamination can give competitive Cosmological constraints when the contaminating distribution is marginalized over in a Bayesian framework.
Peter A R Ade - One of the best experts on this subject based on the ideXlab platform.
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planck 2013 results xvi Cosmological Parameters
arXiv: Cosmology and Nongalactic Astrophysics, 2013Co-Authors: Peter A R Ade, N Aghanim, C Armitagecaplan, M Arnaud, M Ashdown, F Atriobarandela, J Aumont, C Baccigalupi, A J Banday, R B BarreiroAbstract:We present the first results based on Planck measurements of the CMB temperature and lensing-potential power spectra. The Planck spectra at high multipoles are extremely well described by the standard spatially-flat six-parameter LCDM cosmology. In this model Planck data determine the Cosmological Parameters to high precision. We find a low value of the Hubble constant, H0=67.3+/-1.2 km/s/Mpc and a high value of the matter density parameter, Omega_m=0.315+/-0.017 (+/-1 sigma errors) in excellent agreement with constraints from baryon acoustic oscillation (BAO) surveys. Including curvature, we find that the Universe is consistent with spatial flatness to percent-level precision using Planck CMB data alone. We present results from an analysis of extensions to the standard cosmology, using astrophysical data sets in addition to Planck and high-resolution CMB data. None of these models are favoured significantly over standard LCDM. The deviation of the scalar spectral index from unity is insensitive to the addition of tensor modes and to changes in the matter content of the Universe. We find a 95% upper limit of r<0.11 on the tensor-to-scalar ratio. There is no evidence for additional neutrino-like relativistic particles. Using BAO and CMB data, we find N_eff=3.30+/-0.27 for the effective number of relativistic degrees of freedom, and an upper limit of 0.23 eV for the summed neutrino mass. Our results are in excellent agreement with big bang nucleosynthesis and the standard value of N_eff=3.046. We find no evidence for dynamical dark energy. Despite the success of the standard LCDM model, this cosmology does not provide a good fit to the CMB power spectrum at low multipoles, as noted previously by the WMAP team. While not of decisive significance, this is an anomaly in an otherwise self-consistent analysis of the Planck temperature data.
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the atacama cosmology telescope Cosmological Parameters from the 2008 power spectrum
The Astrophysical Journal, 2011Co-Authors: Joanna Dunkley, Renee Hlozek, Viviana Acquaviva, Peter A R Ade, Paula Aguirre, M Amiri, Jon Sievers, J W AppelAbstract:We present Cosmological Parameters derived from the angular power spectrum of the cosmic microwave background (CMB) radiation observed at 148?GHz and 218?GHz over 296?deg2 with the Atacama Cosmology Telescope (ACT) during its 2008 season. ACT measures fluctuations at scales 500 < ? < 10, 000. We fit a model for the lensed CMB, Sunyaev-Zel'dovich (SZ), and foreground contribution to the 148?GHz and 218?GHz power spectra, including thermal and kinetic SZ, Poisson power from radio and infrared point sources, and clustered power from infrared point sources. At ? = 3000, about half the power at 148?GHz comes from primary CMB after masking bright radio sources. The power from thermal and kinetic SZ is estimated to be , where . The IR Poisson power at 148?GHz is (C ? = 5.5 ? 0.5 nK2), and a clustered IR component is required with , assuming an analytic model for its power spectrum shape. At 218?GHz only about 15% of the power, approximately 27 ?K2, is CMB anisotropy at ? = 3000. The remaining 85% is attributed to IR sources (approximately 50% Poisson and 35% clustered), with spectral index ? = 3.69 ? 0.14 for flux scaling as S(?)??. We estimate primary Cosmological Parameters from the less contaminated 148?GHz spectrum, marginalizing over SZ and source power. The ?CDM Cosmological model is a good fit to the data (?2/dof = 29/46), and ?CDM Parameters estimated from ACT+Wilkinson Microwave Anisotropy Probe (WMAP) are consistent with the seven-year WMAP limits, with scale invariant ns = 1 excluded at 99.7% confidence level (CL) (3?). A model with no CMB lensing is disfavored at 2.8?. By measuring the third to seventh acoustic peaks, and probing the Silk damping regime, the ACT data improve limits on Cosmological Parameters that affect the small-scale CMB power. The ACT data combined with WMAP give a 6? detection of primordial helium, with YP = 0.313 ? 0.044, and a 4? detection of relativistic species, assumed to be neutrinos, with N eff = 5.3 ? 1.3 (4.6 ? 0.8 with BAO+H 0 data). From the CMB alone the running of the spectral index is constrained to be dns /dln k = ?0.034 ? 0.018, the limit on the tensor-to-scalar ratio is r < 0.25 (95% CL), and the possible contribution of Nambu cosmic strings to the power spectrum is constrained to string tension G? < 1.6 ? 10?7 (95% CL).
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the atacama cosmology telescope Cosmological Parameters from the 2008 power spectra
arXiv: Cosmology and Nongalactic Astrophysics, 2010Co-Authors: Joanna Dunkley, Renee Hlozek, J L Sievers, Viviana Acquaviva, Peter A R Ade, Paula Aguirre, M Amiri, J W Appel, L F Barrientos, E S BattistelliAbstract:We present Cosmological Parameters derived from the angular power spectrum of the cosmic microwave background (CMB) radiation observed at 148 GHz and 218 GHz over 296 deg^2 with the Atacama Cosmology Telescope (ACT) during its 2008 season. ACT measures fluctuations at scales 500
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Cosmological Parameters from the 2003 flight of boomerang
The Astrophysical Journal, 2006Co-Authors: C J Mactavish, J. R. Bond, Peter A R Ade, J J Bock, J Borrill, A Boscaleri, P Cabella, C R Contaldi, B P CrillAbstract:We present the Cosmological Parameters from the CMB intensity and polarization power spectra of the 2003 Antarctic flight of the BOOMERANG telescope. The BOOMERANG data alone constrain the Parameters of the ΛCDM model remarkably well and are consistent with constraints from a multiexperiment combined CMB data set. We add LSS data from the 2dF and SDSS redshift surveys to the combined CMB data set and test several extensions to the standard model including running of the spectral index, curvature, tensor modes, the effect of massive neutrinos, and an effective equation of state for dark energy. We also include an analysis of constraints to a model that allows a CDM isocurvature admixture.
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Cosmological Parameters from the 2003 flight of boomerang
arXiv: Astrophysics, 2005Co-Authors: C J Mactavish, J. R. Bond, Peter A R Ade, J J Bock, J Borrill, A Boscaleri, P Cabella, C R Contaldi, B P CrillAbstract:We present the Cosmological Parameters from the CMB intensity and polarization power spectra of the 2003 Antarctic flight of the BOOMERANG telescope. The BOOMERANG data alone constrains the Parameters of the $\Lambda$CDM model remarkably well and is consistent with constraints from a multi-experiment combined CMB data set. We add LSS data from the 2dF and SDSS redshift surveys to the combined CMB data set and test several extensions to the standard model including: running of the spectral index, curvature, tensor modes, the effect of massive neutrinos, and an effective equation of state for dark energy. We also include an analysis of constraints to a model which allows a CDM isocurvature admixture.
