We discuss a spectroscopic survey of the strong lensing cluster A1489 that includes redshifts for 195 cluster members along with central velocity dispersions for 188 cluster members. The caustic technique applied to the redshift survey gives the dynamical parameters $M_{200} = (1.25~\pm~0.09) \times 10^{15}~M_\odot$, $r_{200} = 1.97~\pm~{0.05}$ Mpc, and a cluster line-of sight velocity dispersion $1150~\pm~{72}~$km$~$s$^{-1}$ within $r_{200}$. These parameters are very similar to those of other strong lensing systems with comparably large Einstein radii. We use the spectroscopy and deep photometry to demonstrate that A1489 is probably dynamically active; its four BCGs have remarkably different rest frame radial velocities. Like other massive strong lensing clusters, the velocity dispersion function for members of A1489 shows an excess for dispersions $\geq~250~$km$~$s$^{-1}$. The central dispersions also provide enhanced constraints on future lensing models.
We present a first strong-lensing model for the galaxy cluster RM J121218.5+273255.1 ($z=0.35$; hereafter RMJ1212; also known as Abell 1489). This cluster is amongst the top 0.1\% richest clusters in the redMaPPer catalog; it is significantly detected in X-ray and through the Sunyaev-Zel'dovich effect in ROSAT and \emph{Planck} data, respectively; and its optical luminosity distribution implies a very large lens, following mass-to-light scaling relations. Based on these properties it was chosen for the Webb Medium Deep Fields (WMDF) JWST/GTO program. In preparation for this program, RMJ1212 wa…
An Active Galaxy Cluster Merger at Cosmic Noon Revealed by JWST Weak Lensing and Multiwavelength Probes
Yonsei University（延世大学）；California Institute of Technology（加州理工学院）；University of California Davis（加州大学戴维斯分校）；University of Oxford（牛津大学）；University of California, Los Angeles（加州大学洛杉矶分校）
SMACS~J0723.3-7327 is the first galaxy cluster lens observed by JWST. Based on the ERO data from JWST, several groups have reported the results on strong lensing analysis and mass distribution of this cluster. However, limited by the angular coverage of the JWST data, the strong lensing models only cover the central region. X-ray analysis on the hot ICM is necessary to obtain a more complete constraint on the mass distribution in this very massive cluster. In this work, we aim to perform a comprehensive X-ray analysis of J0723 to obtain accurate ICM hydrostatic mass measurements, using the X-r…
Lensed stars in galaxy-galaxy strong lensing -- a JWST prediction for the Cosmic Horseshoe
The University of Hong Kong（香港大学）；University of Portsmouth（朴茨茅斯大学）；Instituto de Física de Cantabria (CSIC-UC)（坎塔布里亚物理研究所（CSIC-UC））；University of Basque Country UPV/EHU（巴斯克大学）；Ikerbasque, Basque Foundation for Science（伊克尔巴斯基，巴斯克科学基金会）；Donostia International Physics Center（圣塞巴斯蒂安国际物理中心）；University of Minnesota（明尼苏达大学）；Universidade Federal do Rio Grande do Sul（南里奥格兰德联邦大学）
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 $z=0.4$
The James Webb Space Telescope (JWST), scheduled for launch in 2014, is expected to revolutionize our understanding of the high-redshift Universe. Even so, many of the most interesting sources that may be hiding at redshifts z~10 (population III stars, dark stars, population III galaxies) are likely to be intrinsically too faint for JWST. Here, we explore the prospects of searching for the first stars and galaxies by pointing JWST through foreground lensing clusters. Observations of this kind can reach significantly deeper than the currently planned JWST ultra deep field in just a fraction of …
Strong LensIng and Cluster Evolution (SLICE) with JWST: Early Results, Lens Models, and High-Redshift Detections
University of Michigan（密歇根大学）；STAR Institute, Quartier Agora - Allée du six Août, 19c B-4000 Liège, Belgium（列日 STAR 研究所）；Durham University（杜伦大学）；Institute for Computational Cosmology, Durham University（杜伦大学计算宇宙学研究所）；Astrophysics Research Centre, University of KwaZulu-Natal（夸祖鲁-纳塔尔大学天体物理研究中心）；School of Mathematics, Statistics & Computer Science, University of KwaZulu-Natal（夸祖鲁-纳塔尔大学数学、统计与计算机科学学院）；Department of Astronomy, University of Washington（华盛顿大学天文学系）；Ecole Polytechnique Fédérale de Lausanne (EPFL)（洛桑联邦理工学院）；Instituto de Física de Cantabria (CSIC-UC)（坎塔布里亚物理研究所）
We give an overview and describe the rationale, methods, and first results from NIRCam images of the JWST "Prime Extragalactic Areas for Reionization and Lensing Science" ("PEARLS") project. PEARLS uses up to eight NIRCam filters to survey several prime extragalactic survey areas: two fields at the North Ecliptic Pole (NEP); seven gravitationally lensing clusters; two high redshift proto-clusters; and the iconic backlit VV 191 galaxy system to map its dust attenuation. PEARLS also includes NIRISS spectra for one of the NEP fields and NIRSpec spectra of two high-redshift quasars. The main goal …
We present a joint strong lensing and stellar dynamical framework for future time-delay cosmography purposes. Based on a pixelated source reconstruction and the axisymmetric Jeans equations, we are capable of constraining cosmological distances and hence the current expansion rate of the Universe ($H_0$) to the few percent level per lens, when high signal-to-noise integral field unit (IFU) observations from the next generation of telescopes become available. For illustrating the power of this method, we mock up IFU stellar kinematic data of the prominent lens system RXJ1131-1231, given the spe…
On 2022 July 8, NASA shared$^{a}$ the list of five public showcase targets which have been observed with the new \textit{James Webb Space Telescope} (JWST), and whose data are expected to be released to the public around Tuesday, July 12. One of these targets is the galaxy cluster SMACS~J0723.3-7327 which acts as a gravitational lens and was recently imaged with the \textit{Hubble Space Telescope} in the framework of the \textit{Reionization Lensing Cluster Survey} program (RELICS). To facilitate studies by the community with the upcoming JWST data, we publish here a lens model for SMACS0723 -…
LEGGOS I: The JWST LEGGOS Survey -- LEnsing and Galaxy Growth: Observing Substructures -- Unpacks the Nature of Clumpy Star Formation and Quenching in Gravitationally Lensed Galaxies beyond Cosmic Noon
University of Washington（华盛顿大学）；University of Pittsburgh（匹兹堡大学）；University of Arizona（亚利桑那大学）；Eureka Scientific（尤里卡科学公司）；University of Cincinnati（辛辛那提大学）；NASA Goddard Space Flight Center（美国国家航空航天局戈达德太空飞行中心）
We present a new strong lensing (SL) model of the Hubble Frontier Fields galaxy cluster Abell 2744, at z=0.3072, by exploiting archival Hubble Space Telescope (HST) multi-band imaging and Multi Unit Spectroscopic Explorer (MUSE) follow-up spectroscopy. The lens model considers 90 spectroscopically confirmed multiple images (from 30 background sources), which represents the largest secure sample for this cluster field prior to the recently acquired James Webb Space Telescope observations. The inclusion of the sub-structures within several extended sources as model constraints allows us to accur…
Fast Lensing And Sub-minute High-accuracy photometry (FLASH) with JWST: Pipeline and Primordial Black Hole Microlensing Constraints from M31
University of Hawai‘i at Mānoa（夏威夷大学马诺阿分校）；E.O. Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；Institute for Astronomy, University of Hawai‘i at Mānoa（夏威夷大学马诺阿分校天文研究所）
We use a dense redshift survey in the foreground of the Subaru GTO2deg^2 weak lensing field (centered at $α_{2000}$ = 16$^h04^m44^s$;$δ_{2000}$ =43^\circ11^{\prime}24^{\prime\prime}$) to assess the completeness and comment on the purity of massive halo identification in the weak lensing map. The redshift survey (published here) includes 4541 galaxies; 4405 are new redshifts measured with the Hectospec on the MMT. Among the weak lensing peaks with a signal-to-noise greater that 4.25, 2/3 correspond to individual massive systems; this result is essentially identical to the Geller et al. (2010) t…
We simulate the effects of gravitational lensing on the source count of high redshift galaxies as projected to be observed by the Hubble Frontier Fields program and the James Webb Space Telescope (JWST) in the near future. Taking the mass density profile of the lensing object to be the singular isothermal sphere (SIS) or the Navarro-Frenk-White (NFW) profile, we model a lens residing at a redshift of z_L = 0.5 and explore the radial dependence of the resulting magnification bias and its variability with the velocity dispersion of the lens, the photometric sensitivity of the instrument, the red…
The first JWST data on the massive colliding cluster El Gordo confirm 23 known families of multiply lensed images and identify 8 new members of these families. Based on these families, which have been confirmed spectroscopically by MUSE, we derived an initial lens model. This model guided the identification of 37 additional families of multiply lensed galaxies, among which 28 are entirely new systems, and 9 were previously known. The initial lens model determined geometric redshifts for the 37 new systems. The geometric redshifts agree reasonably well with spectroscopic or photometric redshift…
Due to the finite amount of observational data, the best-fit parameters corresponding to the reconstructed cluster mass have uncertainties. In turn, these uncertainties affect the inferences made from these mass models. Following our earlier work, we have studied the effect of such uncertainties on the singularity maps in simulated and actual galaxy clusters. The mass models for both simulated and real clusters have been constructed using grale. The final best-fit mass models created using grale give the simplest singularity maps and a lower limit on the number of point singularities that a le…
Still largely unexplored, the diffuse light in cluster of galaxies traces the past and on-going buildup of these massive structures. Here, we present the first comprehensive study of the intracluster light (ICL) of the cluster SMACS-J0723.3-7327 (z=0.39) using the JWST Early Release Observations. These deep and high spatial resolution images allow the study of the ICL with high signal-to-noise ratio up to a radial distance of $\sim400$ kpc, twice as far with respect to previous HST studies of intermediate redshift clusters. This opens up the possibility of exploring the rich mixture of process…
In a recent paper we have discussed the higher order singularities in gravitational lensing. We have shown that a singularity map, comprising of $A_3$-lines and unstable (point) singularities ($A_4$ and $D_4$), is a compact representation of high magnification regions corresponding to a given lens model for all possible source redshifts. It marks all the optimal locations for deep surveys in the lens plane. Here we present singularity maps for ten different cluster lenses selected from the \textit{Hubble Frontier fields} (HFF) and the \textit{Reionization Lensing Cluster Survey} (RELICS) surve…
SLICE -- Combining Strong Lensing and X-ray in AC 114. Further Insights into the Merger Scenario
Aix Marseille Univ, CNRS, CNES, LAM（艾克斯-马赛大学）；Centre for Extragalactic Astronomy, Department of Physics, Durham University（杜伦大学）；Institute for Computational Cosmology, Department of Physics, Durham University（杜伦大学）；Department of Astronomy, University of Michigan（密歇根大学）；Department of Astronomy, University of Geneva（日内瓦大学）；STAR Institute（列日大学天体物理研究所）；Univ Lyon, Univ Lyon1, ENS de Lyon, CNRS, Centre de Recherche Astrophysique de Lyon UMR5574（里昂大学）；Department of Astronomy, University of Washington（华盛顿大学）；Astrophysics Research Centre, University of KwaZulu-Natal（夸祖鲁-纳塔尔大学）；School of Mathematics, Statistics & Computer Science, University of KwaZulu-Natal（夸祖鲁-纳塔尔大学）；Department of Astronomy and Astrophysics, University of Chicago（芝加哥大学）；Kavli Institute for Cosmological Physics, University of Chicago（芝加哥大学）；DIFA – Università di Bologna（博洛尼亚大学）；INAF - IASF Milano（意大利国家天体物理研究所米兰天文台）；INAF – 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空间天体物理观测站）
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…
Model independent lensing sub-structure detection with multiply-imaged star clusters constellations
Durham University（杜伦大学）；Hong Kong University of Science and Technology（香港科技大学）；University of Basque Country UPV/EHU（巴斯克地区大学）；Ikerbasque, Basque Foundation for Science（伊克尔巴斯科，巴斯克科学基金会）；Donostia International Physics Center（圣塞巴斯蒂安国际物理中心）；The University of Hong Kong（香港大学）；The Hong Kong Institute for Astronomy and Astrophysics, The University of Hong Kong（香港大学香港天文及天体物理研究所）；IFCA, Instituto de Física de Cantabria (UC-CSIC)（坎塔布里亚物理研究所 (UC-CSIC)）
Baryonic mass budgets in the central regions of the Bullet Cluster and their consistency with strong lensing in MOND
University of Bonn（波恩大学）；Institute for Advanced Studies in Basic Sciences (IASBS)（基础科学高等研究所）；Institute for Research in Fundamental Sciences (IPM)（基础科学研究院）；University of Portsmouth（朴茨茅斯大学）；Yonsei University（延世大学）
The identification and study of the first galaxies remains one of the most exciting topics in observational cosmology. The determination of the best possible observing strategies is a very important choice in order to build up a representative sample of spectroscopically confirmed sources at high-z (z>7), beyond the limits of present-day observations. This paper is intended to precisely adress the relative efficiency of lensing and blank fields in the identification and study of galaxies at 6<z<12. The detection efficiency and field-to-field variance are estimated from direct simulations of bo…
In the hierarchical structure formation model of the universe, galaxy clusters are assembled through a series of mergers. Accordingly, it is expected that galaxy clusters in the early universe are actively forming and dynamically young. Located at a high redshift of z=1.71, SpARCS1049+56 offers a unique look into the galaxy cluster formation process. This cluster has been shown to be rich in cluster galaxies and to have intense star formation. Its high redshift pushes a weak-lensing analysis beyond the regime of the optical spectrum into that of the infrared. Equipped with deep Hubble Space Te…
The BUFFALO Survey : The Subhalo Mass Function for Abell 2744 with Strong+Weak Gravitational Lensing
Durham University（杜伦大学）；University of KwaZulu-Natal（夸祖鲁-纳塔尔大学）；STAR Institute（STAR研究所）；University of Hertfordshire（赫特福德大学）；Carnegie Observatories（卡内基天文台）
Current surveys are underway to utilize gravitational lensing by galaxy clusters with Einstein radii >35" in the search for the highest redshift galaxies. Associated supernova from the epoch of reionization would have their fluxes boosted above the detection threshold, extending their duration of visibility. We predict that the James Webb Space Telescope (JWST) will be able to discover lensed core-collapse supernovae at redshifts exceeding z=7-8.
