A refined mass distribution of the cluster MACS J0416.1$-$2403 from a new large set of spectroscopic multiply lensed sources
G. B. Caminha, C. Grillo, P. Rosati, I. Balestra, A. Mercurio, E. Vanzella, A. Biviano, K. I. Caputi, C. Delgado-Correal, W. Karman, M. Lombardi, M. Meneghetti,… 展开作者
G. B. Caminha, C. Grillo, P. Rosati, I. Balestra, A. Mercurio, E. Vanzella, A. Biviano, K. I. Caputi, C. Delgado-Correal, W. Karman, M. Lombardi, M. Meneghetti, B. Sartoris, P. Tozzi
We report the spectroscopic confirmation of 22 new multiply lensed sources behind the Hubble Frontier Field (HFF) galaxy cluster MACS~J0416.1$-$2403 (MACS 0416), using archival data from the Multi Unit Spectroscopic Explorer (MUSE) on the VLT. Combining with previous spectroscopic measurements of 15 other multiply imaged sources, we obtain a sample of 102 secure multiple images with measured redshifts, the largest to date in a single strong lensing system. The newly confirmed sources are largely low-luminosity Lyman-$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 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.
We present a revised lens model of MACS J1149+2223, in which the first resolved multiply-imaged lensed supernova was discovered. The lens model is based on the model of Johnson et al. (2014) with some modifications. We include more lensing constraints from the host galaxy of the newly discovered supernova, and increase the flexibility of the model in order to better reproduce the lensing signal in the vicinity of this galaxy. The revised model accurately reconstructs the positions of the lensed supernova, provides magnifications, and predicts the time delay between the instances of the superno…
We report on high-resolution JVLA and Chandra observations of the HST Frontier Cluster MACS J0717.5+3745. MACS J0717.5+3745 offers the largest contiguous magnified area of any known cluster, making it a promising target to search for lensed radio and X-ray sources. With the high-resolution 1.0-6.5 GHz JVLA imaging in A and B configuration, we detect a total of 51 compact radio sources within the area covered by the HST imaging. Within this sample we find 7 lensed sources with amplification factors larger than $2$. None of these sources are identified as multiply-lensed. Based on the radio lumi…
We examine a caustic-straddling arc at $z=0.9397$ in the field of the galaxy cluster MACS J0416.1-2403 ($z=0.397$) using archival multiband HST images and show that its surface brightness exhibits anomalies that can be explained by a single highly magnified star undergoing microlensing. First, we show that the surface brightness pattern is not perfectly symmetric across the cluster critical curve, which is inconsistent with a locally smooth lens model; the location of the candidate star exhibits the most significant asymmetry. Second, our analysis indicates that the asymmetric feature has $\si…
We report the discovery of two extremely magnified lensed star candidates behind the galaxy cluster MACS J0647.7+7015, in recent multi-band James Webb Space Telescope (JWST) NIRCam observations. The candidates are seen in a previously known, $z_{phot}\simeq4.8$ dropout giant arc that straddles the critical curve. The candidates lie near the expected critical curve position but lack clear counter images on the other side of it, suggesting these are possibly stars undergoing caustic crossings. We present revised lensing models for the cluster, including multiply imaged galaxies newly identified …
We present a light-traces-mass (LTM) strong-lensing model of the massive lensing cluster MACS J2135.2-0102 ($z$=0.33; hereafter MACS2135), known in part for hosting the Cosmic Eye galaxy lens. MACS2135 is also known to multiply-lens a $z=$2.3 sub-mm galaxy near the Brightest Cluster Galaxy (BCG), as well as a prominent, triply-imaged system at a large radius of $\sim$37" south of the BCG. We use the latest available Hubble imaging to construct an accurate lensing model for this cluster, identifying six new multiply-imaged systems with the guidance of our LTM method, so that we have roughly qua…
The Grism Lens-Amplified Survey from Space (GLASS) is a Hubble Space Telescope (HST) Large Program, which will obtain 140 orbits of grism spectroscopy of the core and infall regions of 10 galaxy clusters, selected to be among the very best cosmic telescopes. Extensive HST imaging is available from many sources including the CLASH and Frontier Fields programs. We introduce the survey by analyzing spectra of faint multiply-imaged galaxies and $z\gtrsim6$ galaxy candidates obtained from the first seven orbits out of fourteen targeting the core of the Frontier Fields cluster MACS0717.5+3745. Using…
We present the results of a 135-arcmin$^2$ search for high-redshift galaxies lensed by 29 clusters from the MAssive Cluster and extended MAssive Cluster Surveys (MACS and eMACS). We use relatively shallow images obtained with the Hubble Space Telescope in four passbands, namely, F606W, F814W, F110W, and F140W. We identify 130 F814W dropouts as candidates for galaxies at $z \le 6$. In order to fit the available broad-band photometry to galaxy spectral energy distribution (SED) templates, we develop a prior for the level of dust extinction at various redshifts. We also investigate the systematic…
JWST's PEARLS: 119 multiply imaged galaxies behind MACS0416, lensing properties of caustic crossing galaxies, and the relation between halo mass and number of globular clusters at $z=0.4$
We present a detailed strong lensing (SL) mass reconstruction of the core of the galaxy cluster MACSJ 2129.4-0741 ($\rm z_{cl}=0.589$) obtained by combining high-resolution HST photometry from the CLASH survey with new spectroscopic observations from the CLASH-VLT survey. A background bright red passive galaxy at $\rm z_{sp}=1.36$, sextuply lensed in the cluster core, has four radial lensed images located over the three central cluster members. Further 19 background lensed galaxies are spectroscopically confirmed by our VLT survey, including 3 additional multiple systems. A total of 31 multipl…
We report the discovery of a multiply lensed Lyman-$α$ blob (LAB) behind the galaxy cluster AS1063 using the Multi Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope (VLT). The background source is at $z=$ 3.117 and is intrinsically faint compared to almost all previously reported LABs. We used our highly precise strong lensing model to reconstruct the source properties, and we find an intrinsic luminosity of $L_{\rm Lyα}$=$1.9\times10^{42}$ erg s$^{-1}$, extending to 33 kpc. We find that the LAB is associated with a group of galaxies, and possibly a protocluster, in agreement with…
We take advantage of new 100-hour Spitzer/IRAC observations available for MACS0647-JD, a strongly lensed $z\approx11$ galaxy candidate, to provide improved constraints on its physical properties. Probing the physical properties of galaxies at $z>8$ is challenging due to the inherent faintness of such sources and the limited wavelength coverage available. Thanks to the high $\approx$2-6$\times$ lensing magnification of the multiple images of MACS0647-JD, we can use the sensitive Spitzer/IRAC data to probe the rest-frame optical fluxes of MACS0647-JD and investigate its physical properties inclu…
We present a free form mass reconstruction of the massive lensing cluster MACSJ0416.1-2403 using the latest Hubble Frontier Fields data. Our model independent method finds that the extended lensing pattern is generated by two elongated, closely projected clusters of similar mass. Our lens model identifies new lensed images with which we improve the accuracy of the dark matter distribution. We find that the bimodal mass distribution is nearly coincident with the bimodal X-ray emission, but with the two dark matter peaks lying closer together than the centroids of the X-ray emisison. We show thi…
We report the discovery of a multiply-imaged gravitationally lensed Type Ia supernova, iPTF16geu (SN 2016geu), at redshift $z=0.409$. This phenomenon could be identified because the light from the stellar explosion was magnified more than fifty times by the curvature of space around matter in an intervening galaxy. We used high spatial resolution observations to resolve four images of the lensed supernova, approximately 0.3" from the center of the foreground galaxy. The observations probe a physical scale of $\sim$1 kiloparsec, smaller than what is typical in other studies of extragalactic gra…
We report on our first set of spectroscopic Hubble Space Telescope observations of the z~11 candidate galaxy strongly lensed by the MACSJ0647.7+7015 galaxy cluster. The three lensed images are faint and we show that these early slitless grism observations are of sufficient depth to investigate whether this high-redshift candidate, identified by its strong photometric break at ~1.5 micron, could possibly be an emission line galaxy at a much lower redshift. While such an interloper would imply the existence of a rather peculiar object, we show here that such strong emission lines would clearly h…
Individual highly magnified stars have been recently discovered at lookback times of more than half the age of the Universe, in lensed galaxies that straddle the critical curves of massive galaxy clusters. Having confirmed their detectability, it is now important to carry out systematic searches for them in order to establish their frequency, and in turn learn about the statistical properties of high-redshift stars and of the granularity of matter in the foreground deflector. Here we report the discovery of a highly magnified star at redshift $z = 0.94$ in a strongly lensed arc behind a Hubble…
We present a high-precision mass model of the galaxy cluster MACSJ1149.6+2223, based on a strong-gravitational-lensing analysis of Hubble Space Telescope Frontier Fields (HFF) imaging data and spectroscopic follow-up with Gemini/GMOS and VLT/MUSE. Our model includes 12 new multiply imaged galaxies, bringing the total to 22, comprised of 65 individual lensed images. Unlike the first two HFF clusters, Abell 2744 and MACSJ0416.1-2403, MACSJ1149 does not reveal as many multiple images in the HFF data. Using the Lenstool software package and the new sets of multiple images, we model the cluster wit…
We directly detect dust emission in an optically-detected, multiply-imaged galaxy lensed by the Frontier Fields cluster MACSJ0717.5+3745. We detect two images of the same galaxy at 1.1mm with the AzTEC camera on the Large Millimeter Telescope leaving no ambiguity in the counterpart identification. This galaxy, MACS071_Az9, is at z>4 and the strong lensing model (mu=7.5) allows us to calculate an intrinsic IR luminosity of 9.7e10 Lsun and an obscured star formation rate of 14.6 +/- 4.5 Msun/yr. The unobscured star formation rate from the UV is only 4.1 +/- 0.3 Msun/yr which means the total star…
Context: A census of faint and tiny star forming complexes at high redshift is key to improving our understanding of reionizing sources, galaxy growth and the formation of globular clusters. Aims: We present the MUSE Deep Lensed Field (MDLF) program. Methods: We describe Deep MUSE observations of 17.1 hours integration on a single pointing over the Hubble Frontier Field galaxy cluster MACS~J0416. Results: We confirm spectroscopic redshifts for all 136 multiple images of 48 source galaxies at 0.9<z<6.2. Within those galaxies, we securely identify 182 multiple images of 66 galaxy components that…
We present a high-precision mass model of the galaxy cluster MACSJ0416.1-2403, based on a strong-gravitational-lensing analysis of the recently acquired Hubble Space Telescope Frontier Fields (HFF) imaging data. Taking advantage of the unprecedented depth provided by HST/ACS observations in three passbands, we identify 51 new multiply imaged galaxies, quadrupling the previous census and bringing the grand total to 68, comprising 194 individual lensed images. Having selected a subset of the 57 most securely identified multiply imaged galaxies, we use the Lenstool software package to constrain a…
Context: The gravitational lensing time delay method provides a one-step determination of the Hubble constant (H0) with an uncertainty level on par with the cosmic distance ladder method. However, to further investigate the nature of the dark energy, a H0 estimate down to 1% level is greatly needed. This requires dozens of strongly lensed quasars that are yet to be delivered by ongoing and forthcoming all-sky surveys. Aims: In this work we aim to determine the spectroscopic redshift of PSOJ0147, the first strongly lensed quasar candidate found in the Pan-STARRS survey. The main goal of our wor…
We report on the galaxy MACSJ0032-arc at z=3.6314 discovered during the Herschel Lensing snapshot Survey of massive galaxy clusters, and strongly lensed by the cluster MACSJ0032.1+1808. The successful detections of its rest-frame UV, optical, FIR, millimeter, and radio continua, and of its CO emission enable us to characterize, for the first time at such a high redshift, the stellar, dust, and molecular gas properties of a compact star-forming galaxy with a size smaller than 2.5 kpc, a fairly low stellar mass of 4.8x10^9 Msun, and a moderate IR luminosity of 4.8x10^11 Lsun. We find that the bu…
We present a new high-precision parametric strong lensing model of the galaxy cluster MACS J0416.1-2403, at z=0.396, which takes advantage of the MUSE Deep Lensed Field (MDLF), with 17.1h integration in the northeast region of the cluster, and Hubble Frontier Fields data. We spectroscopically identify 182 multiple images from 48 background sources at 0.9<z<6.2, and 171 cluster member galaxies. Several multiple images are associated to individual clumps in multiply lensed resolved sources. By defining a new metric, which is sensitive to the gradients of the deflection field, we show that we can…
Strong lensing by massive galaxy clusters can provide magnification of the flux and even multiple images of the galaxies that lie behind them. This phenomenon facilitates observations of high-redshift supernovae (SNe), that would otherwise remain undetected. Type Ia supernovae (SNe Ia) detections are of particular interest because of their standard brightness, since they can be used to improve either cluster lensing models or cosmological parameter measurements. We present a ground-based, near-infrared search for lensed SNe behind the galaxy cluster Abell 370. Our survey was based on 15 epochs…
Motivated by the preponderance of so-called "heavy black holes" in the binary black hole (BBH) gravitational wave (GW) detections to date, and the role that gravitational lensing continues to play in discovering new galaxy populations, we explore the possibility that the GWs are strongly-lensed by massive galaxy clusters. For example, if one of the GW sources were actually located at $z=1$, then the rest-frame mass of the associated BHs would be reduced by a factor $\sim2$. Based on the known populations of BBH GW sources and strong-lensing clusters, we estimate a conservative lower limit on t…
We present strong-lensing analyses of three galaxy clusters, RXJ2129.4+0009 (z=0.235), MS0451.6-0305 (z=0.55), and MACSJ2129.4-0741 (z=0.589), using the powerful combination of Hubble Space Telescope (HST) multi-band observations, and Multi-Unit Spectroscopic Explorer (MUSE) spectroscopy. In RXJ2129, we newly spectroscopically confirm 15 cluster members. Our resulting mass model uses 8 multiple image systems as we include a galaxy-galaxy lensing system North-East of the cluster, and is composed of 71 halos including one dark matter cluster-scale halo and 2 galaxy-scale halos optimized individu…
We conduct precise strong lensing mass modeling of four ${\it Hubble}$ Frontier Fields (HFF) clusters, Abell$~$2744, MACS$~$J0416.1$-$2403, MACS$~$J0717.5$+$3745, and MACS$~$J1149.6$+$2223, for which HFF imaging observations are completed. We construct a refined sample of more than 100 multiple images for each cluster by taking advantage of the full depth HFF images, and conduct mass modeling using the ${\small \rm GLAFIC}$ software, which assumes simply parametrized mass distributions. Our mass modeling also exploits a magnification constraint from the lensed Type Ia supernova HFF14Tom for Ab…
VENUS: Strong-lensing model of MACS J1931.8-2635 -- revealing the farthest multiply imaged supernova
Ben-Gurion University of the Negev（内盖夫本-古里安大学）；The University of Texas at Austin（德克萨斯大学奥斯汀分校）；The University of Tokyo（东京大学）；University of Toronto（多伦多大学）；Space Telescope Science Institute（太空望远镜科学研究所）
We report the discovery of an intrinsically faint, quintuply-imaged, dusty galaxy MACS0600-z6 at a redshift $z=$6.07 viewed through the cluster MACSJ0600.1-2008 ($z$=0.46). A $\simeq4σ$ dust detection is seen at 1.2mm as part of the ALMA Lensing Cluster Survey (ALCS), an on-going ALMA Large program, and the redshift is secured via [C II] 158 $μ$m emission described in a companion paper. In addition, spectroscopic follow-up with GMOS/Gemini-North shows a break in the galaxy's spectrum, consistent with the Lyman break at that redshift. We use a detailed mass model of the cluster and infer a magn…
We present a strong-lensing analysis of four massive galaxy clusters imaged with the Hubble Space Telescope in the Reionization Lensing Cluster Survey. We use a Light-Traces-Mass technique to uncover sets of multiply images and constrain the mass distribution of the clusters. These mass models are the first published for Abell S295 and MACS J0159.8-0849, and are improvements over previous models for Abell 697 and MACS J0025.4-1222. Our analysis for MACS J0025.4-1222 and Abell S295 shows a bimodal mass distribution supporting the merger scenarios proposed for these clusters. The updated model f…
We derive a free-form mass distribution for the massive cluster AS1063 (z=0.348) using the completed optical imaging from the Hubble Frontier Fields programme. Based on a subset of 11 multiply lensed systems with spectroscopic redshift we produce a lens model that is accurate enough to unveil new multiply lensed systems, totalling over a 100 arclets, and to estimate their redshifts geometrically. Consistency is found between this precise model and that obtained using only the subset of lensed sources with spectroscopically measured redshifts. Although a relatively large elongation of the mass …
A massive galaxy cluster can serve as a magnifying glass for distant stellar populations, with strong gravitational lensing exposing details in the lensed background galaxies that would otherwise be undetectable. The MACS J0416.1-2403 cluster (hereafter MACS0416) is one of the most efficient lenses in the sky, and in 2014 it was observed with high-cadence imaging from the Hubble Space Telescope (HST). Here we describe two unusual transient events that appeared behind MACS0416 in a strongly lensed galaxy at redshift $z = 1.0054 \pm 0.0002$. These transients---designated HFF14Spo-NW and HFF14Spo…
Exploiting the powerful tool of strong gravitational lensing by galaxy clusters to study the highest-redshift Universe and cluster mass distributions relies on precise lens mass modelling. In this work, we present the first attempt at modelling line-of-sight mass distribution in addition to that of the cluster, extending previous modelling techniques that assume mass distributions to be on a single lens plane. We focus on the Hubble Frontier Field cluster MACS J0416.1-2403, and our multi-plane model reproduces the observed image positions with a rms offset of ~0.53". Starting from this best-fi…
The observed lensed fraction of high-redshift quasars $(\sim0.2\%)$ is significantly lower than previous theoretical predictions $(\gtrsim4\%)$. We revisit the lensed fraction of high-redshift quasars predicted by theoretical models, where we adopt recent measurements of galaxy velocity dispersion functions (VDFs) and explore a wide range of quasar luminosity function (QLF) parameters. We use both analytical methods and mock catalogs which give consistent results. For ordinary QLF parameters and the depth of current high-redshift quasar surveys $(m_z\lesssim22)$, our model suggests a multiply-…
We present deep spectroscopic observations of a Lyman-break galaxy candidate (hereafter MACS1149-JD) at $z\sim9.5$ with the $\textit{Hubble}$ Space Telescope ($\textit{HST}$) WFC3/IR grisms. The grism observations were taken at 4 distinct position angles, totaling 34 orbits with the G141 grism, although only 19 of the orbits are relatively uncontaminated along the trace of MACS1149-JD. We fit a 3-parameter ($z$, F160W mag, and Ly$α$ equivalent width) Lyman-break galaxy template to the three least contaminated grism position angles using an MCMC approach. The grism data alone are best fit with …
We present the local HII region metallicity near the site of the recently discovered multiply lensed supernova (SN; "SN Refsdal") at redshift 1.49. "SN Refsdal" is located at the outer spiral arm ($\sim$7 kpc) of the lensed host galaxy, which we have previously reported to exhibit a steep negative galactocentric metallicity gradient. Based on our updated near-infrared integral field spectroscopic data, the gas-phase metallicity averaged in an intrinsic radius of $\sim$ 550 pc surrounding an HII region $\sim$ 200 pc away from the SN site is 12 + log(O/H)$_{\rm PP04N2}$ $\le$ 8.67. The metallici…
We study the population of star-forming clumps in A521-sys1, a $\rm z=1.04$ system gravitationally lensed by the foreground ($\rm z=0.25$) cluster Abell 0521. The galaxy presents one complete counter--image with a mean magnification of $\rm μ\sim4$ and a wide arc containing two partial images of A521-sys1 with magnifications reaching $\rm μ>20$, allowing the investigations of clumps down to scales of $\rm R_{eff}<50$ pc. We identify 18 unique clumps with a total of 45 multiple images. Intrinsic sizes and UV magnitudes reveal clumps with elevated surface brightnesses, comparable to similar syst…
We describe a general purpose method to reconstruct the intrinsic properties of sources lensed by the gravitational potential of foreground clusters of galaxies. The tool Lenstruction is implemented in the publicly available multi-purpose gravitational lensing software Lenstronomy, in order to provide an easy and fast solution to this common astrophysical problem. The tool is based on forward modeling the appearance of the source in the image plane, taking into account the distortion by lensing and the instrumental point spread function (PSF). For singly-imaged sources a global lens model in t…
[abridged] We present a strong-lensing analysis of MACSJ0717.5+3745, based on the full depth of the Hubble Frontier Field (HFF) observations, which brings the number of multiply imaged systems to 61, ten of which are spectroscopically confirmed. The total number of images comprised in these systems rises to 165. Our analysis uses a parametric mass reconstruction technique, as implemented in the Lenstool software, to constrain a mass distribution composed of four large-scale mass components + galaxy-scale perturbers. We find a superposition of cored isothermal mass components to provide a good …
We present a strong and weak gravitational lens model of the galaxy cluster MACSJ0416.1-2403, constrained using spectroscopy from the Grism Lens-Amplified Survey from Space (GLASS) and Hubble Frontier Fields (HFF) imaging data. We search for emission lines in known multiply imaged sources in the GLASS spectra, obtaining secure spectroscopic redshifts of 31 multiple images belonging to 16 distinct source galaxies. The GLASS spectra provide the first spectroscopic measurements for 6 of the source galaxies. The weak lensing signal is acquired from 884 galaxies in the F606W HFF image. By combining…
VENUS: A Strongly Lensed Clumpy Galaxy at $z\sim11-12$ behind the Galaxy Cluster MACS J0257.1-2325
Institute for Cosmic Ray Research, The University of Tokyo（宇宙线研究所，东京大学）；Department of Physics, Graduate School of Science, The University of Tokyo（东京大学理学研究科物理学系）；Department of Astronomy, The University of Texas at Austin（德克萨斯大学奥斯汀分校天文学系）；Cosmic Frontier Center, The University of Texas at Austin（德克萨斯大学奥斯汀分校前沿宇宙学中心）；David A. Dunlap Department of Astronomy and Astrophysics, University of Toronto（多伦多大学戴维·A·邓普天文学与天体物理学系）；Dunlap Institute for Astronomy and Astrophysics（邓普天文学与天体物理研究所）；National Astronomical Observatory of Japan（日本国立天文台）；Department of Astronomical Science, SOKENDAI (The Graduate University for Advanced Studies)（SOKENDAI（高级研究大学院大学）天文学科学系）；Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo（东京大学 Kavli宇宙物理数学研究所（WPI））
The first deep field images from the James Webb Space Telescope (JWST) of the galaxy cluster SMACS~J0723.3-7327 reveal a wealth of new lensed images at uncharted infrared wavelengths, with unprecedented depth and resolution. Here we securely identify 14 new sets of multiply imaged galaxies totalling 42 images, adding to the five sets of bright and multiply-imaged galaxies already known from Hubble Space Telescope data. We find examples of arcs crossing critical curves, allowing detailed community follow-up, such as JWST spectroscopy for precise redshift determinations, and measurements of the …
Hubble Frontier Fields (HFF) imaging of the most powerful lensing clusters provides access to the most magnified distant galaxies. The challenge is to construct lens models capable of describing these complex massive, merging clusters so that individual lensed systems can be reliably identified and their intrinsic properties accurately derived. We apply the free-form lensing method (WSLAP+) to A2744, providing a model independent map of the cluster mass, magnification, and geometric distance estimates to multiply-lensed sources. We solve simultaneously for a smooth cluster component on a pixel…
We present the first observations of the Frontier Fields Cluster Abell S1063 taken with the newly commissioned Multi Unit Spectroscopic Explorer (MUSE) integral field spectrograph. Because of the relatively large field of view (1 arcmin^2), MUSE is ideal to simultaneously target multiple galaxies in blank and cluster fields over the full optical spectrum. We analysed the four hours of data obtained in the Science Verification phase on this cluster and measured redshifts for 53 galaxies. We confirm the redshift of five cluster galaxies, and determine the redshift of 29 other cluster members. Be…
The Frontier Fields project is an observational campaign targeting six galaxy clusters, with the intention of using the magnification provided by gravitational lensing to study galaxies that are extremely faint or distant. We used the Karl G. Jansky Very Large Array (VLA) at 3 and 6 GHz to observe three Frontier Fields: MACSJ0416.1$-$2403 ($z$ = 0.396), MACSJ0717.5+3745 ($z$ = 0.545), and MACSJ1149.5+2223 ($z$ = 0.543). The images reach noise levels of $\sim$1 $μ$Jy beam$^{-1}$ with sub-arcsecond resolution ($\sim$2.5 kpc at $z$ = 3), providing a high-resolution view of high-$z$ star-forming g…
Cosmology with supernova Encore in the strong lensing cluster MACS J0138-2155: Lens model comparison and H0 measurement
Technical University of Munich（慕尼黑工业大学）；Max-Planck-Institut für Astrophysik（马克斯·普朗克天体物理学研究所）；Instituto de Física de Cantabria (CSIC-UC)（坎塔布里亚物理研究所（CSIC-UC））；INAF – IASF Milano（意大利国家天体物理研究所 - 米兰天文物理研究所）；Università degli Studi di Milano（米兰大学）；INAF – OAS, Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所 - 博洛尼亚天文与空间科学观测站）；Yonsei University（延世大学）
SDSS J2222+2745 is a galaxy cluster at z=0.49, strongly lensing a quasar at z=2.805 into six widely separated images. In recent HST imaging of the field, we identify additional multiply lensed galaxies, and confirm the sixth quasar image that was identified by Dahle et al. (2013). We used the Gemini North telescope to measure a spectroscopic redshift of z=4.56 of one of the secondary lensed galaxies. These data are used to refine the lens model of SDSS J2222+2745, compute the time delay and magnifications of the lensed quasar images, and reconstruct the source image of the quasar host and a se…
