Elinor Medezinski - Academia.edu (original) (raw)
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Papers by Elinor Medezinski
The Astrophysical Journal
We derive an accurate mass distribution of the galaxy cluster MACS J1206.2-0847 (z=0.439) from a ... more We derive an accurate mass distribution of the galaxy cluster MACS J1206.2-0847 (z=0.439) from a combined weak-lensing distortion, magnification, and strong-lensing analysis of wide-field Subaru BVRIz' imaging and our recent 16-band Hubble Space Telescope observations taken as part of the Cluster Lensing And Supernova survey with Hubble (CLASH) program. We find good agreement in the regions of overlap between several weak and strong lensing mass reconstructions using a wide variety of modeling methods, ensuring consistency. The Subaru data reveal the presence of a surrounding large scale structure with the major axis running approximately north-west south-east (NW-SE), aligned with the cluster and its brightest galaxy shapes, showing elongation with a \sim 2:1 axis ratio in the plane of the sky. Our full-lensing mass profile exhibits a shallow profile slope dln\Sigma/dlnR\sim -1 at cluster outskirts (R>1Mpc/h), whereas the mass distribution excluding the NW-SE excess regions ...
ABSTRACT Galaxy clusters play a key role in testing cosmological models and in constraining the p... more ABSTRACT Galaxy clusters play a key role in testing cosmological models and in constraining the properties of dark matter. One of these key tests is the mass density profile of clusters - the concentration-mass relation. There is a reported tension between the observed concentration-mass relation and the one theoretically expected using simulated galaxy clusters, where the observed clusters appear to have higher concentration than simulated clusters of similar total mass. In The Cluster Lensing And Supernova survey with Hubble (CLASH), we use different and independent techniques to estimate the mass distribution in clusters. The comparison between different techniques offers an observational test of the techniques and understanding of the systematics. In this work, we estimate the concentration-mass relation for about 8 (at the 0.2< z &;lt; 0.6 redshift range) of the 20 X-ray selected CLASH clusters using galaxy dynamics. We use a unique spectroscopic data set with more than about 300 cluster members per cluster. Finally, we compare our results to the theoretical expected ones and to the estimations derived using the lensing technique.
The Astrophysical Journal, 2015
The Astrophysical Journal, 2009
We directly construct model-independent mass profiles of galaxy clusters from combined weak-lensi... more We directly construct model-independent mass profiles of galaxy clusters from combined weak-lensing distortion and magnification measurements within a Bayesian statistical framework,which allows for a full parameter-space extraction of the underlying signal. This method applies to the full range of radius outside the Einstein radius, and recovers the absolute mass normalization. We apply our method to deep Subaru imaging of five
Astronomy & Astrophysics, 2014
The Cluster Lensing And Supernova survey with Hubble (CLASH) is a 524-orbit multi-cycle treasury ... more The Cluster Lensing And Supernova survey with Hubble (CLASH) is a 524-orbit multi-cycle treasury program to use the gravitational lensing properties of 25 galaxy clusters to accurately constrain their mass distributions. The survey, described in detail in this paper, will definitively establish the degree of concentration of dark matter in the cluster cores, a key prediction of CDM. The CLASH
The Astrophysical Journal, 2014
The Astrophysical Journal, 2012
Monthly Notices of the Royal Astronomical Society, 2009
Monthly Notices of the Royal Astronomical Society, 2010
Modern Physics Letters A, 2008
Weak-lensing induced by clusters of galaxies can probe the total mass distribution out to the vir... more Weak-lensing induced by clusters of galaxies can probe the total mass distribution out to the virial radius of the cluster, regardless of the nature of the mass or its dynamical state. To make a robust analysis, the cluster and background galaxy populations need to be separated. The E/S0 sequence of a cluster defines a boundary redward of which a reliable weak-lensing signal can be obtained from background galaxies, uncontaminated by the cluster. Below this limit, the signal is diluted by the proportion of unlensed cluster members. Employing deep Subaru and HST/ACS images of the massive cluster A1689, we use this dilution effect to carefully separate between the cluster members and the background, and thus derive the cluster light profile and luminosity functions to large radius. The light profile of A1689 is found to decline steadily to the limit of the data, r < 2 h-1Mpc, with a constant slope, d log(L)/d log(r) = -1.12 ± 0.06. We derive a cluster luminosity function with a flat faint-end slope of alpha = -1.05 ± 0.07, nearly independent of radius and with no faint upturn to Mi' < -12. The major advantage of this new approach is that no subtraction of far-field background counts is required.
The Astrophysical Journal
We derive an accurate mass distribution of the galaxy cluster MACS J1206.2-0847 (z=0.439) from a ... more We derive an accurate mass distribution of the galaxy cluster MACS J1206.2-0847 (z=0.439) from a combined weak-lensing distortion, magnification, and strong-lensing analysis of wide-field Subaru BVRIz' imaging and our recent 16-band Hubble Space Telescope observations taken as part of the Cluster Lensing And Supernova survey with Hubble (CLASH) program. We find good agreement in the regions of overlap between several weak and strong lensing mass reconstructions using a wide variety of modeling methods, ensuring consistency. The Subaru data reveal the presence of a surrounding large scale structure with the major axis running approximately north-west south-east (NW-SE), aligned with the cluster and its brightest galaxy shapes, showing elongation with a \sim 2:1 axis ratio in the plane of the sky. Our full-lensing mass profile exhibits a shallow profile slope dln\Sigma/dlnR\sim -1 at cluster outskirts (R>1Mpc/h), whereas the mass distribution excluding the NW-SE excess regions ...
ABSTRACT Galaxy clusters play a key role in testing cosmological models and in constraining the p... more ABSTRACT Galaxy clusters play a key role in testing cosmological models and in constraining the properties of dark matter. One of these key tests is the mass density profile of clusters - the concentration-mass relation. There is a reported tension between the observed concentration-mass relation and the one theoretically expected using simulated galaxy clusters, where the observed clusters appear to have higher concentration than simulated clusters of similar total mass. In The Cluster Lensing And Supernova survey with Hubble (CLASH), we use different and independent techniques to estimate the mass distribution in clusters. The comparison between different techniques offers an observational test of the techniques and understanding of the systematics. In this work, we estimate the concentration-mass relation for about 8 (at the 0.2< z &;lt; 0.6 redshift range) of the 20 X-ray selected CLASH clusters using galaxy dynamics. We use a unique spectroscopic data set with more than about 300 cluster members per cluster. Finally, we compare our results to the theoretical expected ones and to the estimations derived using the lensing technique.
The Astrophysical Journal, 2015
The Astrophysical Journal, 2009
We directly construct model-independent mass profiles of galaxy clusters from combined weak-lensi... more We directly construct model-independent mass profiles of galaxy clusters from combined weak-lensing distortion and magnification measurements within a Bayesian statistical framework,which allows for a full parameter-space extraction of the underlying signal. This method applies to the full range of radius outside the Einstein radius, and recovers the absolute mass normalization. We apply our method to deep Subaru imaging of five
Astronomy & Astrophysics, 2014
The Cluster Lensing And Supernova survey with Hubble (CLASH) is a 524-orbit multi-cycle treasury ... more The Cluster Lensing And Supernova survey with Hubble (CLASH) is a 524-orbit multi-cycle treasury program to use the gravitational lensing properties of 25 galaxy clusters to accurately constrain their mass distributions. The survey, described in detail in this paper, will definitively establish the degree of concentration of dark matter in the cluster cores, a key prediction of CDM. The CLASH
The Astrophysical Journal, 2014
The Astrophysical Journal, 2012
Monthly Notices of the Royal Astronomical Society, 2009
Monthly Notices of the Royal Astronomical Society, 2010
Modern Physics Letters A, 2008
Weak-lensing induced by clusters of galaxies can probe the total mass distribution out to the vir... more Weak-lensing induced by clusters of galaxies can probe the total mass distribution out to the virial radius of the cluster, regardless of the nature of the mass or its dynamical state. To make a robust analysis, the cluster and background galaxy populations need to be separated. The E/S0 sequence of a cluster defines a boundary redward of which a reliable weak-lensing signal can be obtained from background galaxies, uncontaminated by the cluster. Below this limit, the signal is diluted by the proportion of unlensed cluster members. Employing deep Subaru and HST/ACS images of the massive cluster A1689, we use this dilution effect to carefully separate between the cluster members and the background, and thus derive the cluster light profile and luminosity functions to large radius. The light profile of A1689 is found to decline steadily to the limit of the data, r < 2 h-1Mpc, with a constant slope, d log(L)/d log(r) = -1.12 ± 0.06. We derive a cluster luminosity function with a flat faint-end slope of alpha = -1.05 ± 0.07, nearly independent of radius and with no faint upturn to Mi' < -12. The major advantage of this new approach is that no subtraction of far-field background counts is required.