20 research outputs found
CLASH-VLT: A Highly Precise Strong Lensing Model of the Galaxy Cluster RXC J2248.7-4431 (Abell S1063) and Prospects for Cosmography
We perform a comprehensive study of the total mass distribution of the galaxy
cluster RXCJ2248 () with a set of high-precision strong lensing
models, which take advantage of extensive spectroscopic information on many
multiply lensed systems. In the effort to understand and quantify inherent
systematics in parametric strong lensing modelling, we explore a collection of
22 models where we use different samples of multiple image families,
parametrizations of the mass distribution and cosmological parameters. As input
information for the strong lensing models, we use the CLASH HST imaging data
and spectroscopic follow-up observations, carried out with the VIMOS and MUSE
spectrographs, to identify bona-fide multiple images. A total of 16 background
sources, over the redshift range , are multiply lensed into 47 images,
24 of which are spectroscopically confirmed and belong to 10 individual
sources. The cluster total mass distribution and underlying cosmology in the
models are optimized by matching the observed positions of the multiple images
on the lens plane. We show that with a careful selection of a sample of
spectroscopically confirmed multiple images, the best-fit model reproduces
their observed positions with a rms of in a fixed flat CDM
cosmology, whereas the lack of spectroscopic information lead to biases in the
values of the model parameters. Allowing cosmological parameters to vary
together with the cluster parameters, we find (at confidence level)
and for a flat
CDM model, and and
for a universe with and free
curvature. Using toy models mimicking the overall configuration of RXCJ2248, we
estimate the impact of the line of sight mass structure on the positional rms
to be .(ABRIDGED)Comment: 23 pages, 13 figures, accepted for publication in A&
Strong lensing models of eight CLASH clusters from extensive spectroscopy: accurate total mass reconstructions in the cores
We carry out a detailed strong lensing analysis of a sub-sample of eight
galaxy clusters of the CLASH survey, in the redshift range of , using extensive spectroscopic information, primarily MUSE
archival data complemented with CLASH-VLT redshift measurements. Different
models are tested in each cluster depending on the complexity of its mass
distribution and on the number of detected multiple images. Four clusters show
more than five spectroscopically confirmed multiple image families. In this
sample, we do not make use of families that are only photometrically
identified, in order to reduce model degeneracies and systematics due to the
potential misidentifications of some multiple images. We present spectroscopic
confirmation of 27 multiply lensed sources, with no previous spectroscopic
measurements, spanning over the redshift range of .
Moreover, we confirm an average of galaxy members in the core of each
cluster, thanks to the high efficiency and large field of view of MUSE. Despite
having different properties (i.e., number of mass components, total mass,
redshift, etc), the projected total mass and mass density profiles of all
clusters have very similar shapes, when rescaled by independent measurements of
and . Specifically, we measure the mean value of the
projected total mass of our cluster sample within 10 (20)% of to be
0.13 (0.32) of , with a remarkably small scatter of 5 (6)%.
Furthermore, the large number of high-z sources and the precise magnification
maps derived in this work for four clusters add up to the sample of
high-quality gravitational telescopes to be used to study the faint and distant
Universe. The strong lensing models and the full redshift catalogues from MUSE
are publicly available.Comment: 27 pages, 9 figures, 7 tables, updated to match the published
version. Full redshift catalogue and lensing models are available at
http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/632/A3
Spectroscopic identification of high redshift lensed galaxies
We summarize an ongoing observational program, which combines HST imaging, VLT spectroscopy and exploits gravitational lensing of massive clusters, to identify faint lyman-α emitters (3.2 < z < 6.3)
SPECTROSCOPIC IDENTIFICATION OF HIGH REDSHIFT LENSED GALAXIES
We summarize an ongoing observational program, which combines HST imaging, VLT spectroscopy and exploits gravitational lensing of massive clusters, to identify faint Lyman-alpha emitters (3.2 < z < 6.3)
SPECTROSCOPIC IDENTIFICATION OF HIGH REDSHIFT LENSED GALAXIES
We summarize an ongoing observational program, which combines HST imaging, VLT spectroscopy and exploits gravitational lensing of massive clusters, to identify faint lyman-α emitters (3.2 < z < 6.3)
Zentrale Lebensereignisse von Frauen Veraenderungen im Lebensverlaufsmuster in den letzten 30 Jahren
StBA Wiesbaden(282) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
A refined mass distribution of the cluster MACS J0416.1-2403 from a new large set of spectroscopic multiply lensed sources
We report the spectroscopic confirmation of 22 new multiply lensed sources behind the Hubble Frontier Field (HFF) galaxy cluster MACS J0416.1-2403 (MACS 0416), using archival data from the Multi Unit Spectroscopic Explorer (MUSE) on the VLT. Combining with previous spectroscopic measurements of 15 other multiply imaged sources, we have obtained a sample of 102 secure multiple images with measured redshifts, the largest to date in a single strong lensing system. The newly confirmed sources are largely low-luminosity Lyman-alpha emitters with redshift in the range [3.08-6.15]. With such a large number of secure constraints, and a significantly improved sample of galaxy members in the cluster core, we have improved our previous strong lensing model and obtained a robust determination of the projected total mass distribution of MACS 0416. We find evidence of three cored dark-matter halos, adding to the known complexity of this merging system. The total mass density profile, as well as the sub-halo population, are found to be in good agreement with previous works. We update and make public the redshift catalog of MACS 0416 from our previous spectroscopic campaign with the new MUSE redshifts. We also release lensing maps (convergence, shear, magnification) in the standard HFF format
A refined mass distribution of the cluster MACS J0416.1-2403 from a new large set of spectroscopic multiply lensed sources
We report the spectroscopic confirmation of 22 new multiply lensed sources behind the Hubble Frontier Field (HFF) galaxy cluster MACS J0416.1-2403 (MACS 0416), using archival data from the Multi Unit Spectroscopic Explorer (MUSE) on the VLT. Combining with previous spectroscopic measurements of 15 other multiply imaged sources, we have obtained a sample of 102 secure multiple images with measured redshifts, the largest to date in a single strong lensing system. The newly confirmed sources are largely low-luminosity Lyman-α emitters with redshift in the range [ 3.08-6.15 ]. With such a large number of secure constraints, and a significantly improved sample of galaxy members in the cluster core, we have improved our previous strong lensing model and obtained a robust determination of the projected total mass distribution of MACS 0416. We find evidence of three cored dark-matter halos, adding to the known complexity of this merging system. The total mass density profile, as well as the sub-halo population, are found to be in good agreement with previous works. We update and make public the redshift catalog of MACS 0416 from our previous spectroscopic campaign with the new MUSE redshifts. We also release lensing maps (convergence, shear, magnification) in the standard HFF format. Source catalog (full Table A.2) is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr(http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/600/A90</A
VizieR Online Data Catalog: MACS J0416.1-2403 redshift catalogue (Caminha+, 2017)
We used archival MUSE (Bacon et al., 2012, The Messenger, 147, 4) data from two different programs which covered the North-East (NE) and South- West (SW) regions of MACS 0416. (2 data files). <P /