We study possible systematic effects on the values of the cosmological parameters measured through strong lensing analyses of the HFF galaxy cluster MACS J1149.5+2223. We use the observed positions of a large set of spectroscopically selected multiple images, including those of supernova "Refsdal" with their estimated time delays. Starting from our reference model in a flat $Λ$CDM cosmology, published in Grillo et al. (2018), we confirm the relevance of the longest measurable time delay, between SX and S1, and an approximately linear relation between its value and that of $H_{0}$. We perform true blind tests by considering a range of time delays around its original estimate of $345 \pm 10$ days, as an accurate measurement of this time delay was not known at the time of analysis and writing. We investigate separately the impact of a constant sheet of mass at the cluster redshift, of a power-law profile for the mass density of the cluster main halo and of some scatter in the cluster member scaling relations. Remarkably, we find that these systematic effects do not introduce a significant bias on the inferred values of $H_{0}$ and $Ω_{\rm m}$ and that the statistical uncertainties dominate the total error budget: a 3% uncertainty on the time delay of image SX translates into approximately 6% and 40% (including both statistical and systematic $1σ$) uncertainties for $H_{0}$ and $Ω_{\rm m}$, respectively. Furthermore, our model accurately reproduces the extended surface brightness distribution of the supernova host, covering more than $3 \times 10^{4}$ $HST$ pixels. We also present the interesting possibility of measuring the value of the equation-of-state parameter $w$ of the dark energy density, currently with a 30% uncertainty. We conclude that time-delay cluster lenses have the potential to become soon an alternative and competitive cosmological probe.
Our light-traces-mass (LTM) strong-lensing model for MACS J1149.5+2223 has played several key roles over the last decade: it aided the identification of multiple images in this cluster and the study of MACS1149-JD1 at redshift $z\simeq9$, it was used to estimate the properties of the first multiply imaged supernova, Refsdal, in its discovery paper, and of the first caustic crossing event by a cluster, Lensed Star 1. Supernova Refsdal supplied an invaluable opportunity to conduct a blind test of the ability of common lens-modeling techniques to accurately describe the properties of SN Refsdal's…
Multiple image gravitational lensing systems with measured time delays provide a promising one-step method for determining $H_0$. MACS J1149, which lenses SN Refsdal into a quad S1-S4, and two other widely separated images, SX and SY, is a perfect candidate. If time delays are pinned down, the remaining uncertainty arises from the mass distribution in the lens. In MACS J1149, the mass in the relevant lens plane region can be constrained by (i) many multiple images, (ii) the mass of the galaxy splitting S1-S4 (which, we show, is correlated with $H_0$), (iii) magnification of SX (also correlated…
The massive cluster MACSJ1149.5+2223(z=0.544) displays five very large lensed images of a well resolved spiral galaxy at $z_{\rm spect}=1.491$. It is within one of these images that the first example of a multiply-lensed supernova has been detected recently as part of the Grism Lens-Amplified Survey from Space. The depth of this data also reveals many HII regions within the lensed spiral galaxy which we identify between the five counter-images. Here we expand the capability of our free-form method to incorporate these HII regions locally, with other reliable lensed galaxies added for a global …
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…
Supernova "Refsdal," multiply imaged by cluster MACSJ1149.5+2223, represents a rare opportunity to make a true blind test of model predictions in extragalactic astronomy, on a time scale that is short compared to a human lifetime. In order to take advantage of this event, we produced seven gravitational lens models with five independent methods, based on Hubble Space Telescope (HST) Hubble Frontier Field images, along with extensive spectroscopic follow-up observations by HST, the Very Large and the Keck Telescopes. We compare the model predictions and show that they agree reasonably well with…
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 construct a mass model of the cluster MACS J1149.6+2223 to study the expected properties of multiple images of SN Refsdal, the first example of a gravitationally lensed supernova with resolved multiple images recently reported by Kelly et al. We find that the best-fit model predicts six supernova images in total, i.e., two extra images in addition to the observed four Einstein cross supernova images S1--S4. One extra image is predicted to have appeared about 17 years ago, whereas the other extra image is predicted to appear in about one year from the appearance of S1--S4, which is a testabl…
We present a parametric, grid-based lens model for the galaxy cluster MACS J1149.5+2223, concentrating on the properties of the first multiply imaged supernova Refsdal. This model complements our updated light-traces-mass (LTM) strong-lensing model for this cluster, described in a companion paper, and is generated using the same pipeline but with a different parametrization. Together these two models probe different possible solutions in a relatively self-consistent manner and can be used to examine systematic uncertainties and relevant differences between the two parameterizations. We obtain …
Realizing Refsdal's original idea from 1964, we present estimates of the Hubble constant that are complementary to and potentially competitive with those of other cosmological probes. We use the observed positions of 89 multiple images, with extensive spectroscopic information, from 28 background sources and the measured time delays between the images S1-S4 and SX of supernova "Refsdal" ($z = 1.489$), which were obtained thanks to Hubble Space Telescope (HST) deep imaging and Multi Unit Spectroscopic Explorer (MUSE) data. We extend the strong lensing modeling of the Hubble Frontier Fields (HFF…
A boost in the precision of cluster-mass models: Exploiting the extended surface brightness of the lensed supernova Refsdal host galaxy
Università degli Studi di Milano（米兰大学）；INAF – IASF Milano（意大利国家天体物理研究所 - 米兰天文物理研究所）；Instituto de Física de Cantabria (CSIC-UC)（坎塔布里亚物理研究所 (CSIC-UC)）；INAF – OAS, Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所 - 博洛尼亚天文物理与空间科学观测站）；Università di Salerno（萨莱诺大学）；INAF – Osservatorio Astronomico di Capodimonte（意大利国家天体物理研究所 - 卡波迪蒙特天文台）；INFN – Gruppo Collegato di Salerno - Sezione di Napoli（意大利国家核物理研究所 - 萨莱诺协作组 - 那不勒斯分部）
Effects of a central dark matter core on time-delay cosmography with galaxy clusters
Institute of Astronomy and Physics, Inner Mongolia University（内蒙古大学天文与物理学院）；School of Physical Science and Technology, Inner Mongolia University（内蒙古大学物理科学与技术学院）；Center for Frontier Science, Chiba University（千叶大学前沿科学中心）；Department of Physics, Graduate School of Science, Chiba University（千叶大学理学研究科物理学系）
We present the first year of Hubble Space Telescope imaging of the unique supernova (SN) 'Refsdal', a gravitationally lensed SN at z=1.488$\pm$0.001 with multiple images behind the galaxy cluster MACS J1149.6+2223. The first four observed images of SN Refsdal (images S1-S4) exhibited a slow rise (over ~150 days) to reach a broad peak brightness around 20 April, 2015. Using a set of light curve templates constructed from SN 1987A-like peculiar Type II SNe, we measure time delays for the four images relative to S1 of 4$\pm$4 (for S2), 2$\pm$5 (S3), and 24$\pm$7 days (S4). The measured magnificat…
In Hubble Space Telescope (HST) imaging taken on 10 November 2014, four images of supernova (SN) "Refsdal" (redshift z=1.49) appeared in an Einstein-cross--like configuration (images S1-S4) around an early-type galaxy in the cluster MACS J1149.5+2223 (z=0.54). Almost all lens models of the cluster have predicted that the SN should reappear within a year in a second host-galaxy image created by the cluster's potential. In HST observations taken on 11 December 2015, we find a new source at the predicted position of the new image of SN Refsdal approximately 8" from the previous images S1-S4. This…
The time delay between the arrival of photons of multiple images of time variable sources can be used to constrain absolute distances in the Universe (Refsdal 1964), and in turn obtain a direct estimate of the Hubble constant and other cosmological parameters. To convert the time delay into distances, it is well known that the gravitational potential of the main deflector and the contribution of the matter along the line-of-sight need to be known to a sufficient level of precision. In this paper, we discuss a new astrometric requirement that is becoming important as time-delay cosmography impr…
We present MUSE observations in the core of the HFF galaxy cluster MACS J1149.5+2223, where the first magnified and spatially-resolved multiple images of SN 'Refsdal' at redshift 1.489 were detected. Thanks to a DDT program with the VLT and the extraordinary efficiency of MUSE, we measure 117 secure redshifts with just 4.8 hours of total integration time on a single target pointing. We spectroscopically confirm 68 galaxy cluster members, with redshift values ranging from 0.5272 to 0.5660, and 18 multiple images belonging to 7 background, lensed sources distributed in redshifts between 1.240 an…
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…
We present a gravitational lensing model of MACS J1149.5+2223 using ultra-deep Hubble Frontier Fields imaging data and spectroscopic redshifts from HST grism and VLT/MUSE spectroscopic data. We create total mass maps using 38 multiple images (13 sources) and 608 weak lensing galaxies, as well as 100 multiple images of 31 star-forming regions in the galaxy that hosts Supernova Refsdal. We find good agreement with a range of recent models within the HST field of view. We present a map of the ratio of projected stellar mass to total mass ($f_{\star}$), and find that the stellar mass fraction for …
Narrowing down the Hubble constant value by exploiting the extended surface brightness of the supernova Refsdal host galaxy
University of Turku（图尔库大学）；Department of Physics, University of Helsinki（赫尔辛基大学物理系）；University of Helsinki（赫尔辛基大学）；Dipartimento di Fisica, Università degli Studi di Milano（米兰大学物理系）；Università degli Studi di Milano（米兰大学）；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）；INAF – IASF Milano（意大利国家天体物理研究所–米兰天文物理研究所）；Instituto de Física de Cantabria (CSIC-UC)（坎塔布里亚物理研究所（CSIC-UC））；INAF – Istituto di Radioastronomia（意大利国家天体物理研究所–射电天文学研究所）；Università degli Studi di Ferrara（费拉拉大学）；INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所–博洛尼亚天体物理与空间科学观测站）
A Constraint on Dark Matter Self-Interaction from Combined Strong Lensing and Stellar Kinematics in MACS J0138-2155
University of California, Santa Cruz（加州大学圣克鲁兹分校）；Santa Cruz Institute for Particle Physics（圣克鲁兹粒子物理研究所）；Newcastle University（纽卡斯尔大学）；University of Zürich（苏黎世大学）；University of California, Berkeley（加州大学伯克利分校）
Cosmic chronometers with galaxy clusters: a new avenue for multi-probe cosmology
Università di Bologna（博洛尼亚大学）；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天文与空间科学观测站）；Università degli Studi di Ferrara（费拉拉大学）；Università degli Studi di Milano（米兰大学）；Institute of Cosmology and Gravitation, University of Portsmouth（朴茨茅斯大学宇宙学与引力研究所）；INAF – Osservatorio Astronomico di Capodimonte（意大利国家天体物理研究所卡波迪蒙特天文台）；INAF – IASF Milano（意大利国家天体物理研究所米兰天体物理研究所）；Università di Salerno（萨莱诺大学）
The information about the mass density of galaxy clusters provided by the gravitational lens effect has inspired many inversion techniques. In this article, updates to the previously introduced method in Grale are described, and explored in a number of examples. The first looks into a different way of incorporating time delay information, not requiring the unknown source position. It is found that this avoids a possible bias that leads to "over-focusing" the images, i.e. providing source position estimates that lie in a considerably smaller region than the true positions. The second is inspire…
In 1964, Refsdal hypothesized that a supernova whose light traversed multiple paths around a strong gravitational lens could be used to measure the rate of cosmic expansion. We report the discovery of such a system. In Hubble Space Telescope imaging, we have found four images of a single supernova forming an Einstein cross configuration around a redshift z=0.54 elliptical galaxy in the MACS J1149.6+2223 cluster. The cluster's gravitational potential also creates multiple images of the z=1.49 spiral supernova host galaxy, and a future appearance of the supernova elsewhere in the cluster field i…
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）
