The MOSDEF Survey: Kinematic and Structural Evolution of Star-Forming Galaxies at $1.4\leq z\leq 3.8$
Sedona H. Price, Mariska Kriek, Guillermo Barro, Alice E. Shapley, Naveen A. Reddy, William R. Freeman, Alison L. Coil, Irene Shivaei, Mojegan Azadi, Laura de G… 展开作者
Sedona H. Price, Mariska Kriek, Guillermo Barro, Alice E. Shapley, Naveen A. Reddy, William R. Freeman, Alison L. Coil, Irene Shivaei, Mojegan Azadi, Laura de Groot, Brian Siana, Bahram Mobasher, Ryan L. Sanders, Gene C. K. Leung, Tara Fetherolf, Tom O. Zick, Hannah Übler, Natascha M. Förster Schreiber
We present ionized gas kinematics for 681 galaxies at $z\sim 1.4-3.8$ from the MOSFIRE Deep Evolution Field survey, measured using models which account for random galaxy-slit misalignments together with structural parameters derived from CANDELS Hubble Space Telescope (HST) imaging. Kinematics and sizes are used to derive dynamical masses. Baryonic masses are estimated from stellar masses and inferred gas masses from dust-corrected star formation rates (SFRs) and the Kennicutt-Schmidt relation. We measure resolved rotation for 105 galaxies. For the remaining 576 galaxies we use models based on HST imaging structural parameters together with integrated velocity dispersions and baryonic masses to statistically constrain the median ratio of intrinsic ordered to disordered motion, $V/σ_{V,0}$. We find that $V/σ_{V,0}$ increases with increasing stellar mass and decreasing specific SFR (sSFR). These trends may reflect marginal disk stability, where systems with higher gas fractions have thicker disks. For galaxies with detected rotation we assess trends between their kinematics and mass, sSFR, and baryon surface density ($Σ_{\mathrm{bar},e}$). Intrinsic dispersion correlates most with $Σ_{\mathrm{bar},e}$ and velocity correlates most with mass. By comparing dynamical and baryonic masses, we find that galaxies at $z\sim 1.4-3.8$ are baryon dominated within their effective radii ($R_E$), with Mdyn/Mbaryon increasing over time. The inferred baryon fractions within $R_E$, $f_{\mathrm{bar}}$, decrease over time, even at fixed mass, size, or surface density. At fixed redshift, $f_{\mathrm{bar}}$ does not appear to vary with stellar mass but increases with decreasing $R_E$ and increasing $Σ_{\mathrm{bar},e}$. For galaxies at $z\geq2$, the median inferred baryon fractions generally exceed 100%. We discuss possible explanations and future avenues to resolve this tension.
Using the near-IR spectroscopy of the MOSFIRE Deep Evolution Field (MOSDEF) survey, we investigate the role of local environment in the gas-phase metallicity of galaxies. The local environment measurements are derived from accurate and uniformly calculated photometric redshifts with well-calibrated probability distributions. Based on rest-frame optical emission lines, [NII]$\lambda6584$ and H$α$, we measure gas-phase oxygen abundance of 167 galaxies at $1.37\leq z\leq1.7$ and 303 galaxies at $2.09\leq z\leq2.61$, located in diverse environments. We find that at $z\sim1.5$, the average metallic…
We present H$α$ gas kinematics for 178 star-forming galaxies at z~2 from the MOSFIRE Deep Evolution Field survey. We have developed models to interpret the kinematic measurements from fixed-angle multi-object spectroscopy, using structural parameters derived from CANDELS HST/F160W imaging. For 35 galaxies we measure resolved rotation with a median $(V/σ_{V,0})_{R_E}=2.1$. We derive dynamical masses from the kinematics and sizes and compare them to baryonic masses, with gas masses estimated from dust-corrected H$α$ star formation rates (SFRs) and the Kennicutt-Schmidt relation. When assuming th…
Using the MOSDEF rest-frame optical spectroscopic survey, we investigate the star-formation histories (SFHs) of different galaxy types, ranging from actively star forming to quiescent at $1.4\leq~z\leq2.6$. SFHs are constrained utilizing stellar continuum spectroscopy, specifically through a combination of Balmer absorption lines, the 4000$Å$ break, and the equivalent width of the H$α$ emission line. To attain a sufficiently high signal-to-noise ratio (S/N) to conduct these measurements we stack spectra of galaxies with similar spectral types, as determined from their rest-frame $U-V$ and $V-J…
We study the properties of 30 spectroscopically-identified pairs of galaxies observed during the peak epoch of star formation in the universe. These systems are drawn from the MOSFIRE Deep Evolution Field (MOSDEF) Survey at $1.4 \leq z \leq 3.8$, and are interpreted as early-stage galaxy mergers. Galaxy pairs in our sample are identified as two objects whose spectra were collected on the same Keck/MOSFIRE spectroscopic slit. Accordingly, all pairs in the sample have projected separations $R_{\rm proj}\leq 60$ kpc. The velocity separation for pairs was required to be $Δv \leq 500 \mbox{ km s}^{…
Using data from the MOSFIRE Deep Evolution Field (MOSDEF) survey, we present a census of AGN-driven ionized outflows in a sample of 159 AGNs at $1.4 \le z \le 3.8$. The sample spans AGN bolometric luminosities of $10^{44-47} \mathrm{~erg~s}^{-1}$ and includes both quiescent and star-forming galaxies extending across three orders of magnitude in stellar mass. We identify and characterize outflows from the \hbeta, [OIII], \halpha ~and [NII] emission line spectra. We detect outflows in $17\%$ of the AGNs, seven times more often than in a mass-matched sample of inactive galaxies in MOSDEF. The out…
We use the large spectroscopic data set of the MOSFIRE Deep Evolution Field survey to investigate the kinematics and energetics of ionised gas outflows. Using a sample of 598 star-forming galaxies at redshift 1.4 < $z$ < 3.8, we decompose $\rm{H}α$ and [OIII] emission lines into narrow and broad components, finding significant detections of broad components in 10% of the sample. The ionised outflow velocity from individual galaxies appears independent of galaxy properties, such as stellar mass, star-formation rate (SFR), and star-formation-rate surface density ($Σ_{\rm SFR}$). Adopting a simpl…
The complex structure of gas, metals, and dust in the interstellar and circumgalactic medium (ISM and CGM, respectively) in star-forming galaxies can be probed by Ly$α$ emission and absorption, low-ionization interstellar (LIS) metal absorption, and dust reddening E(B-V). We present a statistical analysis of the mutual correlations among Ly$α$ equivalent width (EW$_{Lyα}$), LIS equivalent width (EW$_{LIS}$), and E(B-V) in a sample of 157 star-forming galaxies at $z\sim2.3$. With measurements obtained from individual, deep rest-UV spectra and spectral-energy distribution (SED) modeling, we find…
IllustrisTNG50 angular momentum maps: tracing the morpho-kinematic evolution of galaxies
Aix-Marseille Univ.（艾克斯-马赛大学）；CNRS（法国国家科学研究中心）；CNES（法国国家空间研究中心）；LAM（拉格朗日天体物理实验室）；French-Chilean Laboratory for Astronomy, IRL 3386, CNRS and Universidad de Concepción, Departamento de Astronomía（中智天文联合实验室，智利康塞普西翁大学天文学系）；Universidad de Concepción（智利康塞普西翁大学）；Observatoire Astronomique de Strasbourg, UMR 7550, CNRS, Université de Strasbourg（斯特拉斯堡天文台，斯特拉斯堡大学）
We present rest-optical spectroscopic properties of a sample of four galaxies in the Atacama Large Millimeter/submillimeter Array Hubble Ultra Deep Field (ALMA HUDF). These galaxies span the redshift range $1.41 \leq z \leq 2.54$ and the stellar mass range $10.36\leq\log(M_*/{\rm M}_{\odot})\leq10.91$. They have existing far-infrared and radio measurements of dust-continuum and molecular gas emission from which bolometric star-formation rates (SFRs), dust masses, and molecular gas masses have been estimated. We use new $H$- and $K$-band near-infrared spectra from the Keck/MOSFIRE spectrograph …
Outflows and rotation are two ubiquitous kinematic features in the gas kinematics of galaxies. Here we introduce a semi-analytic model to quantify how rotating outflows impact the morphology of the Lyman-$α$ emission line. The model is contrasted against Monte Carlo radiative transfer simulations of outflowing gas with additional solid body rotation. We explore a range of neutral Hydrogen optical depth of $10^5 \leq τ_{\mathrm{H}} \leq10^7$, rotational velocity $0 \leq v_{\mathrm{rot}}/\mathrm{km\ s}^{-1} \leq 100$ and outflow velocity $0\leq v_{\mathrm{out}}/\mathrm{km\ s}^{-1} \leq 50$. We f…
We investigate the Milky Way Galaxy's radial and vertical metallicity gradients using a sample of 47,406 red clump stars from the RAVE DR4. This sample is more than twice the size of the largest sample in the literature investigating radial and vertical metallicity gradients. The absolute magnitude of Groenewegen (2008) is used to determine distances to our sample stars. The resulting distances agree with the RAVE DR4 distances Binney et al. (2014) of the same stars. Our photometric method also provides distances to 6185 stars that are not assigned a distance in RAVE DR4. The metallicity gradi…
We study the gas distribution and kinematics of the inner kpc of six moderately luminous (43.43$\leq$log$L_{\rm bol}\leq$44.83) nearby ($0.004 \leq z \leq 0.014$) Seyfert galaxies observed with the Near-infrared Integral Field Spectrograph (NIFS) in the J(1.25$μ$m) and K(2.2$μ$m) bands. We analyse the most intense emission lines detected on these spectral wavebands: [Fe II] 1.2570 $μ$m and Pa$β$, which trace the ionised gas in the partially and fully ionised regions, and H$_2$2.1218$μ$m, that traces the hot ($\sim 2000$ K) molecular gas. The dominant kinematic component is rotation in the disc…
We characterize the Gaia-Enceladus-Sausage kinematic structure recently discovered in the Galactic halo using photometric metallicities from the SkyMapper survey, and kinematics from Gaia radial velocities measurements. By examining the metallicity distribution functions (MDFs) of stars binned in kinematic/action spaces, we find that the $\sqrt{J_R}$ vs $L_z$ space allows for the cleanest selection of Gaia-Enceladus-Sausage stars with minimal contamination from disc or halo stars formed in situ or in other past mergers. Stars with $30 \leq \sqrt{J_R} \leq 50$ (kpc km s$^{-1})^{1/2}$ and $-500 …
We discuss constraints on the mass density distribution (parameterized as $ρ\propto r^{-γ}$) in early-type galaxies provided by strong lensing and stellar kinematics data. The constraints come from mass measurements at two `pinch' radii. One `pinch' radius $r_1=2.2 R_{Einst}$ is defined such that the Einstein (i.e. aperture) mass can be converted to the spherical mass almost independently of the mass-model. Another `pinch' radius $r_2=R_{opt}$ is chosen so that the dynamical mass, derived from the line-of-sight velocity dispersion, is least sensitive to the anisotropy of stellar orbits. We ver…
Galaxy mergers and interactions are expected to play a significant role leading to offsets between gas and stellar motions in galaxies. Herein we crossmatch galaxies in MaNGA MPL-8 with the Dark Energy Spectroscopic Instrument (DESI) Legacy Surveys and identify 311 merging galaxies that have reliable measurements of the $Δ$PA, the difference between the stellar and gas kinematic position angles to investigate the impacts of merging on gas-stellar rotation misalignments. We find that the merging fractions of misaligned galaxies (30$^\circ$ $\leqslant$ $Δ$PA $<$150$^\circ$) are higher than that …
Mapping the Galactic disk with the LAMOST and Gaia Red clump sample: VIII: Mapping the kinematics of the Galactic disk using mono-age and mono-abundance stellar populations
Correlations between stellar chemistry and kinematics have long been used to gain insight into the evolution of the Milky Way Galaxy. Orbital angular momentum is a key physical parameter and it is often estimated from three-dimensional space motions. We here demonstrate the lower uncertainties that can be achieved in the estimation of one component of velocity through selection of stars in key directions and use of line-of-sight velocity alone (i.e. without incorporation of proper motion data). In this first paper we apply our technique to stars observed in the direction of Galactic rotation i…
Stellar halos contain tracers of the assembly history of massive galaxies like our own. Exploiting the synergy between the TGAS and the spectroscopic RAVE surveys, Helmi et al. (2017) recently discovered several distinct substructures in the Solar neighbourhood, defined in integrals of motion space. Some of these substructures may be examples of the building blocks that built up the stellar halo. We analyse the chemical properties of stars in these substructures, with focus on their iron and $α$-element abundances as provided by the RAVE survey chemical pipeline. We perform comparisons of the …
In this work, we explore the diversity of ionised gas kinematics (rotational velocity $v_ϕ$ and velocity dispersion $σ_{\mathrm{g}}$) and gas-phase metallicity gradients at $0.1 \leq z \leq 2.5$ using a compiled data set of 74 galaxies resolved with ground-based integral field spectroscopy. We find that galaxies with the highest and the lowest $σ_{\mathrm{g}}$ have preferentially flat metallicity gradients, whereas those with intermediate values of $σ_{\mathrm{g}}$ show a large scatter in the metallicity gradients. Additionally, steep negative gradients appear almost only in rotation-dominated…
We aim to probe the dynamic structure of the extended Solar neighbourhood by calculating the radial metallicity gradients from orbit properties, which are obtained for axisymmetric and non-axisymmetric potential models, of red clump (RC) stars selected from the RAdial Velocity Experiment's Fourth Data Release. Distances are obtained by assuming a single absolute magnitude value in near-infrared, i.e. $M_{Ks}=-1.54\pm0.04$ mag, for each RC star. Stellar orbit parameters are calculated by using the potential functions: (i) for the MWPotential2014 potential, (ii) for the same potential with pertu…
We used the spectroscopic and astrometric data provided from the GALAH DR2 and Gaia DR2, respectively, for a large sample of stars to investigate the behaviour of the [$α$/Fe] abundances via two procedures, i.e. kinematically and spectroscopically. With the kinematical procedure, we investigated the distribution of the [$α$/Fe] abundances into the high/low probability thin disc, and high/low probability thick-disc populations in terms of total space velocity, [Fe/H] abundance, and age. The high probability thin-disc stars dominate in all sub-intervals of [$α$/Fe], including the rich ones: [$α$…
Metal-poor stars play an import role in the understanding of Galaxy formation and evolution. Evidence of the early mergers that built up the Galaxy might remain in the distributions of abundances, kinematics, and orbital parameters of the stars. In this work, we report on preliminary results of an on-going chemo-kinematic analysis of a sample of metal-poor ([Fe/H] $\leq$ -1.0) stars observed by the GALAH spectroscopic survey. We explored the chemical and orbital data with unsupervised machine learning (hierarchical clustering, k-means cluster analysis and correlation matrices). Our final goal …
We observed twelve nearby HI -detected early-type galaxies (ETGs) of stellar mass $\sim 10^{10}M\odot \leq M_* \leq \sim 10^{11}M\odot$ with the Mitchell Integral-Field Spectrograph, reaching approximately three half-light radii in most cases. We extracted line-of-sight velocity distributions for the stellar and gaseous components. We find little evidence of transitions in the stellar kinematics of the galaxies in our sample beyond the central effective radius, with centrally fast-rotating galaxies remaining fast-rotating and centrally slow-rotating galaxies likewise remaining slow-rotating. T…
The turbulent dynamo is a powerful mechanism that converts turbulent kinetic energy to magnetic energy. A key question regarding the magnetic field amplification by turbulence, is, on what scale, $k_{\rm p}$, do magnetic fields become most concentrated? There has been some disagreement about whether $k_{\rm p}$ is controlled by the viscous scale, $k_ν$ (where turbulent kinetic energy dissipates), or the resistive scale, $k_η$ (where magnetic fields dissipate). Here we use direct numerical simulations of magnetohydrodynamic turbulence to measure characteristic scales in the kinematic phase of t…
High Velocity Neutral Gas in the Fermi Bubbles: New Kinematic Limits and Spatial Structure
Green Bank Observatory, National Radio Astronomy Observatory（绿岸天文台，国家射电天文台）；Università di Firenze, Dipartimento di Fisica e Astronomia（佛罗伦萨大学，物理与天文学系）；INAF - Osservatorio Astrofisico di Arcetri（意大利国家天体物理研究所-阿尔切特里天文台）；Department of Astronomy, University of California Berkeley（加州大学伯克利分校天文学系）；AURA for ESA, Space Telescope Science Institute（欧洲空间局美国天文研究协会，太空望远镜科学研究所）
We investigate the shape of the Rotation Curves (RCs) of $z\sim 1$ star-forming galaxies and compare them with the local star-forming galaxies. For this purpose, we have used $409$ galaxies from the K-band Multi-Object Spectrograph (KMOS) for Redshift One Spectroscopic Survey (KROSS). This sample covers the redshift range $0.57\leq z \leq 1.04$, effective radii $0.69 \leq R_e \left[kpc \right] \leq 7.73$, absolute H-band magnitude $-24.46 \leq M_H \leq -18.85$ with median stellar mass $log\left(M_* \ \left[M_\odot \right]\right)=9.95$ and median total star-formation rate $log\left(SFR_{tot} \ …
We present deep observations of a $z=1.4$ massive, star-forming galaxy in molecular and ionized gas at comparable spatial resolution (CO 3-2, NOEMA; H$α$, LBT). The kinematic tracers agree well, indicating that both gas phases are subject to the same gravitational potential and physical processes affecting the gas dynamics. We combine the one-dimensional velocity and velocity dispersion profiles in CO and H$α$ to forward-model the galaxy in a Bayesian framework, combining a thick exponential disk, a bulge, and a dark matter halo. We determine the dynamical support due to baryons and dark matte…
The kinematic characterization of different galaxy populations is a key observational input to distinguish between different galaxy evolutionary scenarios, since it helps to determine the number ratio of rotating disks to mergers at different cosmic epochs. Local (U)LIRGs offer a unique opportunity to study at high linear resolution and S/N extreme star forming events and compare them with those observed at high-z. We obtained Very Large Telescope (VLT) VIMOS optical integral field spectroscopy (IFS) data of a sample of 38 (U)LIRGs. The `unweighted' and `weighted' {kinemetry}-based methods are…
From protogalaxy through thick and thin: Why did the Milky Way evolve in three kinematic phases?
University of California, Irvine（加州大学尔湾分校）；University of Southern California（南加州大学）；The University of Texas at Austin（德克萨斯大学奥斯汀分校）；Center for Astrophysics | Harvard & Smithsonian（哈佛-史密森尼天体物理中心）；Northwestern University（西北大学）；University of Zurich（苏黎世大学）；Yale University（耶鲁大学）；Pomona College（波莫纳学院）；Carnegie Observatories（卡内基观测站）
Abridged: We used the fourth internal data release of the Gaia-ESO survey to characterize the bulge chemistry, spatial distribution, kinematics, and to compare it chemically with the thin and thick disks. The sample consist on ~2500 red clump stars in 11 bulge fields ($-10^\circ\leq l\leq+8^\circ$ and $-10^\circ\leq b\leq-4^\circ$), and a set of ~6300 disk stars selected for comparison. The bulge MDF is confirmed to be bimodal across the whole sampled area, with metal-poor stars dominating at high latitudes. The metal-rich stars exhibit bar-like kinematics and display a bimodality in their mag…
We study the stellar morphological evolution of disc galaxies within clusters in the TNG50 and TNG100 runs from the IllustrisTNG simulation suite. We select satellites of masses $10^{9.7} \leq M_{*,z=0}/\text{M}_{\odot} \leq 10^{11.6}$ residing in clusters of masses $10^{14} \lesssim M_{\text{200c,z=0}}/\text{M}_{\odot} \leq 10^{14.6}$ at $z=0$ and that were discs at accretion according to a kinematic morphology indicator (the circularity fraction). These are traced from the time of accretion to $z=0$ and compared to a control sample of central galaxies mass-matched at accretion. Most cluster …
We study the metallicity distribution and kinematic properties of 4,680 A/F/G/K-type giant stars with $|z|>$ 5 kpc selected from the LAMOST spectroscopic survey. The metallicity distribution of giant stars with 5 $<|z|\leqslant$ 15 kpc can be described by a three-peak Gaussian model with peaks at [Fe/H] $\sim-0.6\pm0.1$, $-1.2\pm0.3$ and $-2.0\pm0.2$, corresponding to the ratio of 19$\%$, 74$\%$ and 7$\%$, respectively. The $\rm{[α/Fe]}$ is used to associate the three peaks with the thick disk, inner-halo and outer-halo components of the Galaxy. The metallicity distribution of these giant star…
The accuracy in determining the spatial-kinematical parameters of open clusters makes them ideal tracers of the Galactic structure. Young open clusters (YOCs) are the main representative of the clustered star formation mode, which identifies how most of the stars in the Galaxy form. We apply the Kriging technique to a sample of Gaia YOCs within a 3.5 kpc radius around the Sun and log(age) $\leq$ 7.5, age in years, to obtain the $Z(X,Y)$ and $V_Z(X,Y)$ maps. The previous work by Alfaro et al. (1991) showed that Kriging can provide reliable results even with small data samples ($N \sim 100$). We…
We compare dynamical mass estimates based on spatially extended stellar and ionized gas kinematics ($\mathrm{M_{dyn,*}}$ and $\mathrm{M_{dyn,eml}}$, respectively) of 157 star forming galaxies at $0.6\leq z<1$. Compared to $z\sim0$, these galaxies have enhanced star formation rates, with stellar feedback likely affecting the dynamics of the gas. We use LEGA-C DR3, the highest redshift dataset providing sufficiently deep measurements of a $K_s-$band limited sample. For $\mathrm{M_{dyn,*}}$ we use Jeans Anisotropic Multi-Gaussian Expansion models. For $\mathrm{M_{dyn,eml}}$ we first fit a custom …
Galaxy mergers are central to our understanding of galaxy formation, especially within the context of hierarchical models. Besides having a large impact on the star formation history, mergers are also able to influence gas motions at the centre of galaxies and trigger an Active Galactic Nucleus (AGN). In this paper, we present a case study of the Seyfert galaxy NGC 2992, which together with NGC 2993 forms the early-stage merger system Arp 245. Using Gemini Multi-Object Spectrograph (GMOS) integral field unit (IFU) data from the inner 1.1 kpc of the galaxy we were able to spatially resolve the …
We present a two-dimensional mapping of stellar population age components, emission-line fluxes, gas excitation and kinematics within the inner $\sim200$ pc of the Seyfert 2 galaxy NGC 2110. We used the Gemini North Integral Field Spectrograph (NIFS) in the J and K bands at a spatial resolution of $\sim22$ pc. The unresolved nuclear continuum is originated in combined contributions of young stellar population (SP; age$\leq100$ Myr), a featureless AGN continuum and hot dust emission. The young-intermediate SP ($100<$age$\leq700$ Myr) is distributed in a ring-shaped structure at $\approx140$ pc …
Metal-Poor Gas Accretion Drives Giant Clump Formation at 0.6 < z < 2.6
University of Colorado（科罗拉多大学）；York University（约克大学）；University of California, Davis（加州大学戴维斯分校）；University of California, Merced（加州大学默塞德分校）；Harvard University（哈佛大学）；University of Toronto（多伦多大学）；Dunlap Institute for Astronomy and Astrophysics（邓普勒天文学与天体物理研究所）
We present results of MUSE-ALMA Halos, an ongoing study of the Circumgalactic Medium (CGM) of galaxies ($z \leq$ 1.4). Using multi-phase observations we probe the neutral, ionised and molecular gas in a sub-sample containing six absorbers and nine associated galaxies in the redshift range $z \sim 0.3-0.75$. Here, we give an in-depth analysis of the newly CO-detected galaxy Q2131-G1 ($z=0.42974$), while providing stringent mass and depletion time limits for the non-detected galaxies. Q2131-G1 is associated with an absorber with column densities of $\textrm{log}(N_\textrm{HI}/\textrm{cm}^{-2}) \…
Here, we report comparative study of radial velocity ($\rm RV$) data of two major surveys: Gaia Data Release 2 and RAVE Data Release 5. We restricted the sample to stars with relatively accurate radial velocities ($σ_{\rm RV_{Gaia}} \leq$ 2 km s$^{-1}$ or $\leq$ 2%, and $σ_{\rm RV_{RAVE}}\leq$ 2 km s$^{-1}$ or $\leq$ 2%). The difference between $\rm RV_{Gaia}$ and $\rm RV_{RAVE}$ for a majority of the sample follows normal distribution with mean = 0.28 km s$^{-1}$ and $σ$ = 1.49 km s$^{-1}$. However, we found a very small group of stars ($\approx 0.08\%$ of the total) for which the difference …
Composite Bulges -- V. Detecting signatures of gas inflows in IFU data: The MUSE view of ionised gas kinematics in nearby galaxies
Liverpool John Moores University（利物浦约翰摩尔大学）；University of Nottingham（诺丁汉大学）；Max-Planck-Institut für extraterrestrische Physik（马克斯·普朗克地外物理学研究所）；Universitäts-Sternwarte München（慕尼黑大学天文台）；Durham University（杜伦大学）；Universidade de São Paulo, Instituto de Astronomia, Geofísica e Ciências Atmosféricas（圣保罗大学天文学、地球物理与大气科学研究所）；University of Lancashire（兰开夏大学）；Universidad de La Laguna（拉帕鲁纳大学）
We describe the hCOSMOS redshift survey of the COSMOS field conducted with the Hectospec spectrograph on the MMT. In the central 1~deg$^2$, the hCOS20.6 subset of the survey is $>90\%$ complete to a limiting $r=20.6$. The hCOSMOS survey includes 1701 new redshifts in the COSMOS field. We also use the total of 4362 new and remeasured objects to derive the age sensitive D$_n4000$ index over the entire redshift interval $0.001\lesssim z\lesssim0.6$. For $85\%$ of the quiescent galaxies in hCOS20.6, we measure the central line-of-sight velocity dispersion. To explore potential uses of this survey,…
In this letter, we investigate the impact of environment on integrated and spatially-resolved stellar kinematics of a sample of massive, quiescent galaxies at intermediate redshift ($0.6<z<1.0$). For this analysis, we combine photometric and spectroscopic parameters from the UltraVISTA and Large Early Galaxy Astrophysics Census (LEGA-C) surveys in the COSMOS field and environmental measurements. We analyze the trends with overdensity (1+$δ$) on the rotational support of quiescent galaxies and find no universal trends at either fixed mass or fixed stellar velocity dispersion. This is consistent…
In this paper we present the new deep images from the VEGAS survey of three massive ($M_{*} \simeq 10^{12}$~M$_\odot$) galaxies from the MUSE Most Massive Galaxies (M3G) project, with distances in the range $151\leq D \leq 183$ Mpc: PGC007748, PGC015524 and PGC049940. The long integration time and the wide field of view of OmegaCam@VST allowed us to map the light and color distributions down to $μ_g\simeq30$~mag/arcsec$^2$ and out to $\sim 2R_e$. The deep data are crucial to estimate the contribution of the different galaxy's components, in particular the accreted fraction in the stellar halo.…
KBSS-InCLOSE II: First Detailed Insights on the Inner CGM of Low-Mass $z\sim2.3$ Galaxies
University of California, Los Angeles（加州大学洛杉矶分校）；Carnegie Observatories（卡内基天文台）；California Institute of Technology（加州理工学院）；Department of Physics, University of Notre Dame（圣母大学物理系）；Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), Northwestern University（西北大学天体物理学跨学科探索与研究中心）
Direct measurements of the masses of supermassive black holes (SMBHs) are key to understanding their growth and constrain their symbiotic relationship to their host galaxies. However, current methods used to directly measure black hole masses in active quasars become challenging or impossible beyond $z\gtrsim0.2$. Spectroastrometry (SA) measures the spatial centroid of an object's spectrum as a function of wavelength, delivering angular resolution far better than the point-spread function (PSF) for high signal-to-noise ratio observations. We observed the luminous quasar SDSS J212329.47--005052…
Unveiling the physical properties and kinematics of molecular gas in the Antennae Galaxies (NGC 4038/9) through high resolution CO (J = 3-2) observations
