Interstellar dust plays a crucial role in gas cooling and molecule formation, influencing galaxy evolution. However, the composition and structure of dust in distant galaxies are still poorly understood. We have started a JWST MIRI MRS program investigating the dust features in gas-rich and dusty galaxies at redshifts $z<$1.2, with strong 2175~Å bumps detected in absorption along the lines of sight to distant background quasars. Here we describe our program strategy, and present MIRI MRS observations of IR dust features at $z=0.5-1.2$ in five quasar spectra that form the first part of our full sample. We identify artifacts in MIRI MRS data that affect the background in IFU cubes, and propose methods to reduce their effects. We pay special attention to modeling the quasar mid-IR continuum, which shows significant variation depending on AGN morphology, redshift, and black hole mass. Dust in foreground galaxies produces significant absorption from the 10~$μ$m silicate feature in all five quasar spectra. Compared with the average 10~$μ$m silicate feature in the diffuse ISM of the Milky Way, we find differences in the absorption peak position, width of the features, and asymmetry of the profiles. A detailed study of these silicate features is presented in our next paper (Klimenko et al. 2026b). In two quasar spectra, we tentatively detect weak IR features near 3.0 and 3.4~$μ$m. Their strengths are comparable to those seen in the Milky Way ISM, but follow-up observations are required to confirm these detections.
Exploring the gaseous halos of z>3 radio galaxies with UVES and JWST/NIRSpec
Max-Planck-Institut für Astrophysik（马克斯·普朗克天体物理学研究所）；Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg（海德堡大学天文学计算研究所）；IPAC, California Institute of Technology（加州理工学院IPAC）；European Southern Observatory（欧洲南方天文台）
First Observation of CO$_2$ Emission and foreground absorption Toward the Galactic Center with JWST
University of California, Los Angeles（加州大学洛杉矶分校）；Observatoire de Paris（巴黎天文台）；PSL Research University（PSL研究大学）；CNRS（法国国家科学研究中心）；Sorbonne Université（索邦大学）；Université Paris Cité（巴黎西岱大学）；Texas State University（德克萨斯州立大学）
A Super-Eddington, Lensing-Magnified Quasar at $z=5.07$ observed with JWST
Massachusetts Institute of Technology（麻省理工学院）；University of Arizona（亚利桑那大学）；MIT Kavli Institute for Astrophysics and Space Research（麻省理工学院卡弗里天体物理与空间研究所）；University of Michigan（密歇根大学）
Identifying Red Supergiants in the Local Group Using JWST Photometry. I. NGC 6822, Sextans A, NGC 300, WLM, and IC 1613
Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University（北京师范大学天文与前沿科学研究院）；School of Physics and Astronomy, Beijing Normal University（北京师范大学物理与天文学院）；Key Laboratory of Space Astronomy and Technology, National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台空间天文与技术重点实验室）；Department of Astronomy, College of Physics and Electronic Engineering, Qilu Normal University（齐鲁师范学院物理与电子工程学院天文学系）
To fully exploit the potential of quasars as probes of cosmic chemical evolution and the internal gas dynamics of galaxies it is important to understand the selection effects behind the quasar samples and in particular if the selection criteria exclude foreground galaxies with certain properties (most importantly a high dust content). Here we present spectroscopic follow-up from the 10.4-m GTC telescope of a dust-reddened quasar, eHAQ0111+0641, from the extended High A_V Quasar (HAQ) survey. We find that the z=3.21 quasar has a foreground Damped Lyman-alpha Absorber (DLA) at z=2.027 along the …
A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE): JWST Discovers an Overdensity around a Metal Absorption-selected Galaxy at $z\sim5.5$
Probing Dust Composition in Distant Galaxies with JWST Mid-IR Spectroscopy of Quasars with Foreground 2175 Å Absorbers II. Measurements of Grain Composition and Extinction Properties
University of South Carolina（南卡罗来纳大学）；Georgia Southern University（佐治亚南方大学）
We present evidence of a >10-sigma detection of the 10 micron silicate dust absorption feature in the spectrum of the gravitationally lensed quasar PKS 1830-211, produced by a foreground absorption system at redshift 0.886. We have examined more than 100 optical depth templates, derived from both observations of Galactic and extragalactic sources and laboratory measurements, in order to constrain the chemical structure of the silicate dust. We find that the best fit to the observed absorption profile is produced by laboratory crystalline olivine, with a corresponding peak optical depth of tau_…
ATLAS. II. Extremely High Incidence of Balmer Line Absorption with Predominant Blueshifts in LRDs: Statistical Insights through Comparison with Type 1 AGNs
Institute for Cosmic Ray Research, The University of Tokyo（东京大学宇宙射线研究所）；Department of Physics, Graduate School of Science, The University of Tokyo（东京大学理学研究科物理系）；National Astronomical Observatory of Japan（日本国立天文台）；Astronomical Science Program, Graduate Institute for Advanced Studies, SOKENDAI（SOKENDAI高级研究院天文学科学项目）；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））
We explore the expected galaxy environments of CIV absorbers at z>5 using the Technicolor Dawn simulations. These simulations reproduce the observed history of reionization, the z~6 galaxy stellar mass function, the Ly$α$ forest transmission at z>5, and the SiIV column density distribution (CDD) at z~5.5. Nonetheless, the CIV CDD remains underproduced. Comparison with observed CII/SiII equivalent width ratios and the CII line incidence suggests that a low carbon yield accounts for some, but not all, of the CIV discrepancy. Alternatively, a density-bounded escape scenario could harden the metag…
JWSTs PEARLS: NIRCam imaging and NIRISS spectroscopy of a $z=3.6$ star-forming galaxy lensed into a near-Einstein Ring by a $z=1.258$ massive elliptical galaxy
We present a detailed study of the quasar-galaxy pair: J1243+4043 - UGC07904. The sight line of the background quasar ( $z_q$= 1.5266) passes through a region of the galaxy ($z_g$=0.0169) at an impact parameter of 6.9 kpc with high metallicity (0.5 Z$_\odot$) and negligible dust extinction. We detect HI 21-cm absorption from the foreground galaxy at arcsecond and milliarcsecond scales. For typical cold neutral medium (CNM) temperatures in the Milky Way, this 21-cm absorber can be classified as a damped Ly$α$ absorber (DLA). We infer the harmonic mean spin temperature of the gas to be $\sim$400…
The THESAN-ZOOM project: The Hidden Neighbours of OI Absorbers during Reionization
University of Edinburgh（爱丁堡大学）；York University（约克大学）；Leibniz-Institut für Astrophysik Potsdam（波茨坦阿基米德天体物理研究所）；The University of Texas at Dallas（得克萨斯大学达拉斯分校）；University of Pennsylvania（宾夕法尼亚大学）；The University of Tokyo（东京大学）；Massachusetts Institute of Technology（麻省理工学院）；Center for Astrophysics | Harvard & Smithsonian（哈佛史密森尼天体物理中心）
Mapping the z>=5 SiIV Column Density Distribution onto the Galaxy Stellar Mass Function Using the Cumulative Absorption Cross Section
New Mexico State University（新墨西哥州立大学）；Cosmic Dawn Center (DAWN), Niels Bohr Institute, University of Copenhagen / DTU-Space, Technical University of Denmark（哥本哈根大学尼尔斯·玻尔研究所宇宙黎明中心(DAWN)/丹麦技术大学DTU空间）；Vanderbilt University（范德堡大学）；Space Telescope Science Institute（太空望远镜科学研究所）
JWST spectroscopy of galaxies at $z>10$: Damped Ly$α$ absorbers reveal efficient star formation and hidden redshift biases
DTU Space, Technical University of Denmark（丹麦技术大学空间中心）；Cosmic Dawn Center (DAWN)（宇宙黎明中心）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；Leiden Observatory, Leiden University（莱顿大学莱顿天文台）；The Kavli Institute for Cosmology (KICC), University of Cambridge（剑桥大学卡弗里宇宙学研究所）；Cavendish Laboratory, University of Cambridge（剑桥大学卡文迪许实验室）；Department of Astronomy, University of Geneva（日内瓦大学天文学系）；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）
JADES: Discovery of Large Reservoirs of Small Dust Grains in the Circumgalactic Medium of Massive Galaxies at $z\sim3.5$ through Deep JWST/NIRCam Imaging and Grism Spectroscopy
University of Cambridge（剑桥大学）；Steward Observatory, University of Arizona（亚利桑那大学斯图尔德天文台）；The Pennsylvania State University（宾夕法尼亚州立大学）；Tsinghua University（清华大学）
Damped Lyman-α Absorbers (DLAs) as a class of QSO absorption-line systems are currently our most important source of detailed information on the cosmic chemical evolution of galaxies. However, the degree to which this information is biased by dust remains to be understood. One strategy is to specifically search for QSOs reddened by metal-rich and dusty foreground absorbers. In this Letter we present the discovery of a z=2.60 QSO strongly reddened by dust in an intervening extremely-strong DLA at z=2.226. This QSO was identified through a novel selection combining the astrometric measurements f…
We present results on gas flows in the halo of a Milky Way-like galaxy at z=0.413 based on high-resolution spectroscopy of a background galaxy. This is the first study of circumgalactic gas at high spectral resolution towards an extended background source (i.e., a galaxy rather than a quasar). Using longslit spectroscopy of the foreground galaxy, we observe spatially extended H alpha emission with circular rotation velocity v=270 km/s. Using echelle spectroscopy of the background galaxy, we detect Mg II and Fe II absorption lines at impact parameter rho=27 kpc that are blueshifted from systemi…
We conduct a comprehensive study on dropout galaxy candidates at $z\sim9-16$ using the first 90 arcmin$^2$ JWST/NIRCam images taken by the early release observations (ERO) and early release science (ERS) programs. With the JWST simulation images, we find that a number of foreground interlopers are selected with a weak photo-$z$ determination ($Δχ^2>4$). We thus carefully apply a secure photo-$z$ selection criterion ($Δχ^2>9$) and conventional color criteria with confirmations of the ERO NIRSpec spectroscopic redshifts, and obtain a total of 23 dropout galaxies at $z\sim9-16$, including two can…
JWST's PEARLS: A clumpy ring galaxy at $z = 4.0148$
University of Illinois（伊利诺伊大学）；Durham University（杜伦大学）；Arizona State University（亚利桑那州立大学）；Chinese Academy of Sciences South America Center for Astronomy, National Astronomical Observatories, CAS（中国科学院南天文中心，国家天文台，中科院）；Jodrell Bank Centre for Astrophysics, University of Manchester（曼彻斯特大学乔德雷尔银行天体物理学中心）；Instituto de Fisica de Cantabria (CSIC-UC)（坎塔布里亚物理研究所（西班牙科学理事会-坎塔布里亚大学））；University of Arizona（亚利桑那大学）；Space Telescope Science Institute（太空望远镜科学研究所）
We wish to study the extent and subparsec scale spatial structure of intervening quasar absorbers, mainly those involving neutral and molecular gas. We have selected quasar absorption systems with high spectral resolution and good S/N data, with some of their lines falling on quasar emission features. By investigating the consistency of absorption profiles seen for lines formed either against the quasar continuum source or on the much more extended emission line region (ELR), we can probe the extent and structure of the foreground absorber over the extent of the ELR (0.3-1 pc). The spatial cov…
A hot, nebular-dominated galaxy interacting with a pristine PopIII system uncovered by JWST
Cosmic Dawn Center (DAWN)（宇宙黎明中心）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；DTU Space, Technical University of Denmark（丹麦技术大学空间科学中心）
A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE): Impact of Galaxies on the CGM Metal Enrichment at z > 6 Using the JWST and VLT
High-redshift binary quasars provide key insights into mergers and quasar activity, and are useful tools for probing the spatial kinematics and chemistry of galaxies along the line-of-sight. However, only three sub-10-kpc binaries have been confirmed above $z=1$. Gravitational lensing would provide a way to easily resolve such binaries, study them in higher resolution, and provide more sightlines, though the required alignment with a massive foreground galaxy is rare. Through image deconvolution of StanCam Nordic Optical Telescope (NOT) monitoring data, we reveal two further point sources in t…
Limited constraints on the evolution of the Lyman Continuum (LyC) escape fraction represent one of the primary uncertainties in the theoretical determination of the reionization history. Due to the intervening intergalactic medium (IGM), the possibility of observing LyC photons directly in the epoch of reionization is highly unlikely. For this reason, multiple indirect probes of LyC escape have been identified, some of which are used to identify low-redshift LyC leakers (e.g. O32), while others are primarily useful at $z>6$ (e.g. [OIII]/[CII] far infrared emission). The flux ratio of the reson…
Absorption spectroscopy of gravitationally lensed quasars (GLQs) enables study of spatial variations in the interstellar and/or circumgalactic medium of foreground galaxies. We report observations of 4 GLQs, each with two images separated by 0.8-3.0", that show strong absorbers at redshifts 0.4$<$$z_{abs}$$<$1.3 in their spectra, including some at the lens redshift with impact parameters 1.5-6.9 kpc. We measure H I Lyman lines along two sight lines each in five absorbers (10 sight lines in total) using HST STIS, and metal lines using Magellan Echellette or Sloan Digital Sky Survey. Our data ha…
Universidad Complutense de Madrid（马德里康普顿斯大学）；SKA Observatory（平方公里阵列望远镜观测站）；The Australian National University（澳大利亚国立大学）；University of Minnesota（明尼苏达大学）；Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）；National Astronomical Observatory of Japan（日本国立天文台）；Hamburg University（汉堡大学）；INAF – Istituto di Radioastronomia（意大利国家天体物理研究所射电天文分部）
Next generation observatories will enable us to study the first billion years of our Universe in unprecedented detail. Foremost among these are 21-cm interferometry with the HERA and the SKA, and high-$z$ galaxy observations with the James Webb Space Telescope (JWST). Taking a basic galaxy model, in which we allow the star formation rates and ionizing escape fractions to have a power-law dependence on halo mass with an exponential turnover below some threshold, we quantify how observations from these instruments can be used to constrain the astrophysics of high-$z$ galaxies. For this purpose, …
A dense, metal-rich absorber driven by a heavily dust-obscured galaxy: The direct evidence of CGM enrichment at $z\sim7$
University of Toronto（多伦多大学）；Dunlap Institute for Astronomy and Astrophysics（邓普天文学与天体物理研究所）；University of Copenhagen（哥本哈根大学）；Niels Bohr Institute（尼尔斯·玻尔研究所）；Steward Observatory, University of Arizona（亚利桑那大学斯图尔德天文台）；MIT Kavli Institute for Astrophysics and Space Research（麻省理工学院卡弗里天体物理学与空间研究学院）；Massachusetts Institute of Technology（麻省理工学院）
We performed multi-band deep imaging of the field around GRB 050730 to identify the host galaxies of intervening absorbers, which consist of a damped Lyα absorption (DLA) system at zabs=3.564, a sub-DLA system at zabs=3.022, and strong MgII absorption systems at zabs=1.773 and 2.253. Our observations were performed after the gamma-ray burst afterglow had disappeared. Thus, our imaging survey has a higher sensitivity to the host galaxies of the intervening absorbers than the normal imaging surveys in the direction of QSOs, for which the QSO glare tends to hide the foreground galaxies. In this d…
Strong singly-ionized magnesium (MgII) absorption lines in quasar spectra typically serve as a proxy for intervening galaxies along the line of sight. Previous studies have found a correlation between the number of these MgII absorbers and the Faraday rotation measure (RM) at $\approx5$ GHz. We cross-match a sample of 35,752 optically-identified non-intrinsic MgII absorption systems with 25,649 polarized background radio sources for which we have measurements of both the spectral index and RM at 1.4 GHz. We use the spectral index to split the resulting sample of 599 sources into flat-spectrum …
Early Results from GLASS-JWST. XXV. Electron Density in the Interstellar Medium at $0.7\lesssim z\lesssim 9.3$ with NIRSpec High-resolution Spectroscopy
We present the first results from a Hubble Space Telescope WFC3/IR program, which obtained direct imaging and grism observations of galaxies near quasar sightlines with a high frequency of uncorrelated foreground Mg II absorption. These highly efficient observations targeted 54 Mg II absorbers along the line of sight to nine quasars at $z_{qso}\sim2$. We find that 89% of the absorbers in the range $0.64< z < 1.6$ can be spectroscopically matched to at least one galaxy with an impact parameter less than 200 kpc and $|Δz|/(1+z)<0.006$. We have estimated the star formation rates and measured stru…
We derive the spatial and wavelength behavior of dust attenuation in the multiple-armed spiral galaxy VV191b using backlighting by the superimposed elliptical system VV191a in a pair with an exceptionally favorable geometry for this measurement. Imaging using JWST and HST spans the wavelength range 0.3-4.5 microns with high angular resolution, tracing the dust in detail from 0.6 to 1.5 microns. Distinct dust lanes continue well beyond the bright spiral arms, and trace a complex web, with a very sharp radial cutoff near 1.7 Petrosian radii. We present attenuation profiles and coverage statistic…
The Multiphase CGM in the Epoch of Reionization: CII and CIV absorbers around [OIII] Emitters
University of Trieste（的里雅斯特大学）；INAF - Osservatorio Astronomico di Trieste（意大利国家天体物理研究所的里雅斯特天文台）；IFPU - Institute for Fundamental Physics of the Universe（宇宙基础物理研究所）；Dipartimento di Fisica “Enrico Fermi”, Università di Pisa（比萨大学恩里科·费米物理系）；IUCAA（印度联合大学天体物理中心）；Università degli Studi di Milano-Bicocca（米兰比可卡大学）；Max-Planck-Institut für Ex
We now have mounting evidences that the circumgalactic medium (CGM) of galaxies is polluted with metals processed through stars. The fate of these metals is however still an open question and several findings indicate that they remain poorly mixed. A powerful tool to study the low-density gas of the CGM is offered by absorption lines in quasar spectra, although the information retrieved is limited to 1D along the sightline. We report the serendipitous discovery of two close-by bright z_gal=1.148 extended galaxies with a fortuitous intervening z_abs=1.067 foreground absorber. MUSE IFU observati…
MUSE-ALMA Haloes XVI: a census of the condensed baryons in z~0.5 HI absorption-selected galaxies
European Southern Observatory（欧洲南方天文台）；Centre for Astrophysics and Supercomputing, Swinburne University of Technology（斯威本科技大学天体物理与超级计算中心）；CSIRO Space & Astronomy（CSIRO空间与天文学部）；CNRS（法国国家科学研究中心）；Max-Planck-Institut für extraterrestrische Physik（马克斯·普朗克地外物理研究所）；Stockholm University（斯德哥尔摩大学）；Kavli Institute for Cosmology, University of Cambridge（剑桥大学卡弗里宇宙学研究所）；Cavendish Laboratory, University of Cambridge（剑桥大学卡文迪许实验室）
Context. Absorbing galaxies are selected via the detection of characteristic absorption lines which their gas-rich media imprint in the spectra of distant light-beacons. The proximity of the typically faint foreground absorbing galaxies to bright background sources makes it challenging to robustly identify these in emission, and hence to characterise their relation to the general galaxy population. Aims. We search for emission to confirm and characterise ten galaxies hosting damped, metal-rich quasar absorbers at redshift z < 1. Methods. We identify the absorbing galaxies by matching spectrosc…
Absorption lines in the spectra of distant quasars whose sightlines pass through foreground galaxies provide a valuable tool to probe the dust and gas compositions of the interstellar medium (ISM) in galaxies. The first evidence of silicate dust in a quasar absorption system (QAS) was provided through our detection of the 10 micron silicate feature in the z=0.52 absorber toward the quasar AO 0235+164. We present results from 2 follow-up programs using archival Spitzer Space Telescope infrared spectra to study the interstellar silicate dust grain properties in a total of 13 QASs at 0.1<z<1.4. W…
All the Massive Galaxy Overdensities during Reionization: JWST Rest-Frame Optical Selection Reveals Young, Chemically Evolved Galaxies Embedded in Dense, Neutral Gas at z > 5
Cosmic Dawn Center (DAWN)（宇宙黎明中心）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；DTU Space, Technical University of Denmark（丹麦技术大学空间科学中心）；Institute of Science and Technology Austria (ISTA)（奥地利科学技术研究院）；MIT Kavli Institute for Astrophysics and Space Research（麻省理工学院卡弗里天体物理与空间研究所）；Department of Astronomy, University of Geneva（日内瓦大学天文系）；National Astronomical Observatory of Japan（日本国立天文台）；INAF/Osservatorio Astronomico di Roma（意大利国家天体物理研究所罗马天文台）
Early Results from GLASS-JWST. XXVI. Spatially Resolved Star Formation and Balmer Decrements at $1.1<z<2.3$ from NIRISS Slitless Spectroscopy
School of Astronomy and Space Science, University of Chinese Academy of Sciences (UCAS)（中国科学院大学天文与空间科学学院）；Institute for Frontiers in Astronomy and Astrophysics, Beijing Normal University（北京师范大学天文与前沿科学研究院）；National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）；Department of Physics and Astronomy, University of California Davis（加州大学戴维斯分校物理与天文学系）；Centre for Astrophysics and Supercomputing, Swinburne University of Technology（斯威本科技大学天体物理学与超级计算中心）；Department of Physics and Astronomy, University of California, Los Angeles（加州大学洛杉矶分校物理与天文学系）；Cosmic Dawn Center (DAWN)（宇宙黎明中心）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）
Some fraction of narrow absorption lines are physically associated to the quasar/host-galaxy materials (i.e., intrinsic NALs) like those of BALs and mini-BALs. The relation between these three types of absorption lines has not been understood yet, however one interpretation is that these absorption features correspond to different inclination angles. In this study, we search for intrinsic NALs in 11 BAL/mini-BAL quasar spectra retrieved from VLT/UVES public archive, in order to test a possible relation of intrinsic NALs and BALs/mini-BALs in the geometry models. We use partial coverage analysi…
We present the first results of an ALMA spectral survey of strong absorption lines for common interstellar species in the z=0.89 molecular absorber toward the lensed blazar PKS1830-211. The dataset brings essential information on the structure and composition of the absorbing gas in the foreground galaxy. In particular, we find absorption over large velocity intervals (gtrsim 100 km/s) toward both lensed images of the blazar. This suggests either that the galaxy inclination is intermediate and that we sample velocity gradients or streaming motions in the disk plane, that the molecular gas has …
