Recent stacked ALMA observations have revealed that normal, star-forming galaxies at $z\approx 6$ are surrounded by extended ($\approx 10\,\mathrm{kpc}$) [CII] emitting halos which are not predicted by the most advanced, zoom-in simulations. We present a model in which these halos are the result of supernova-driven cooling outflows. Our model contains two free parameters, the outflow mass loading factor, $η$, and the parent galaxy dark matter halo circular velocity, $v_c$. The outflow model successfully matches the observed [CII] surface brightness profile if $η= 3.20 \pm 0.10$ and $v_c = 170 \pm 10{\,\rm km\,s^{-1}}$, corresponding to a dynamical mass of $\approx 10^{11}\, \mathrm{M}_\odot$. The predicted outflow rate and velocity range are $128 \pm 5 \,\mathrm{M}_\odot {\rm yr}^{-1}$ and $300-500 {\,\rm km\,s^{-1}}$, respectively. We conclude that: (a) extended halos can be produced by cooling outflows; (b) the large $η$ value is marginally consistent with starburst-driven outflows, but it might indicate additional energy input from AGN; (c) the presence of [CII] halos requires an ionizing photon escape fraction from galaxies $f_{\rm esc} \ll 1$. The model can be readily applied also to individual high-$z$ galaxies, as those observed, e.g., by the ALMA ALPINE survey now becoming available.
ALMA observations have revealed that many high redshift galaxies are surrounded by extended (10-15 kpc) [CII]-emitting halos which are not predicted by even the most advanced zoom-in simulations. Using a semi-analytical model, in a previous work we suggested that such halos are produced by starburst-driven, catastrophically cooling outflows. Here, we further improve the model and compare its predictions with data from 7 star-forming ($10\lesssim \rm SFR/ M_\odot \rm yr^{-1}<100$) galaxies at z=4-6, observed in the ALPINE survey. We find that (a) detected [CII] halos are a natural by-product of…
We present the stacking analysis of a sample of 48 QSOs at 4.5<z<7.1 detected by ALMA in the [CII] 158 micron line to investigate the presence and the properties of massive, cold outflows traced by broad [CII] wings. We reveal very broad [CII] wings tracing the presence of outflows with velocities in excess of 1000 km/s. We find that the luminosity of the broad [CII] emission increases with LAGN, while it does not significantly depend on the SFR of the host galaxy, indicating that the central AGN is the main driving mechanism of the [CII] outflows in these powerful, distant QSOs. From the stac…
We report a tentative correlation between the outflow characteristics derived from OH absorption at $119\,μ\text{m}$ and [CII] emission at $158\,μ\text{m}$ in a sample of 22 local and bright ultraluminous infrared galaxies (ULIRGs). For this sample we investigate whether [CII] broad wings are a good tracer of molecular outflows, and how the two tracers are connected. Fourteen objects in our sample have a broad wing component as traced by [CII], and all of these also show OH119 absorption indicative of an outflow (in 1 case an inflow). The other eight cases, where no broad [CII] component was f…
Past observations of QSO host galaxies at z >6 have found cold gas and star formation on compact scales of a few kiloparsecs. We present new high sensitivity IRAM PdBI follow-up observations of the [CII] 158micron emission line and FIR continuum in the host galaxy of SDSS J1148+5152, a luminous QSO at redshift 6.4189. We find that a large fraction of the gas traced by [CII] is at high velocities, up to ~1400 km/s relative to the systemic velocity, confirming the presence of a major quasar-driven outflow indicated by previous observations. The outflow has a complex morphology and reaches a maxi…
We combine available constraints on the local CII 158 $μ$m line luminosity function from galaxy observations (Hemmati et al. 2017), with the evolution of the star-formation rate density and the recent CII intensity mapping measurement in Pullen et al. (2018, assuming detection), to derive the evolution of the CII luminosity - halo mass relation over $z \sim 0-6$. We develop convenient fitting forms for the evolution of the CII luminosity - halo mass relation, and forecast constraints on the CII intensity mapping power spectrum and its associated uncertainty across redshifts. We predict the sen…
We report the discovery of 10-kpc scale [CII] 158um halos surrounding star-forming galaxies in the early Universe. We choose deep ALMA data of 18 galaxies each with a star-formation rate of ~ 10-70 Msun with no signature of AGN whose [CII] lines are individually detected at z=5.153-7.142, and conduct stacking of the [CII] lines and dust-continuum in the uv-visibility plane. The radial profiles of the surface brightnesses show a 10-kpc scale [CII] halo at the 9.2sigma level significantly extended more than the HST stellar continuum data by a factor of ~5 on the exponential-profile basis, as wel…
We present the physical extent of [CII] 158um line-emitting gas from 46 star-forming galaxies at z=4-6 from the ALMA Large Program to INvestigate CII at Early Times (ALPINE). Using exponential profile fits, we measure the effective radius of the [CII] line (r_e,[CII]) for individual galaxies and compare them with the rest-frame ultra-violet (UV) continuum (r_e,UV) from Hubble Space Telescope images. The effective radius r_e,[CII] exceeds r_e,UV by factors of ~2-3 and the ratio of r_e,[CII]/r_e,UV increases as a function of M_star. We do not find strong evidence that [CII] line, the rest-frame …
We present the first attempt to detect outflows from galaxies approaching the Epoch of Reionization (EoR) using a sample of 9 star-forming ($\rm SFR=31\pm 20~M_{\odot}~yr^{-1}$) $z\sim 5.5$ galaxies for which the [CII]158$μ$m line has been previously obtained with ALMA. We first fit each line with a Gaussian function and compute the residuals by subtracting the best fitting model from the data. We combine the residuals of all sample galaxies and find that the total signal is characterised by a flux excess of $\sim 0.5$ mJy extended over $\sim 1000$ km~s$^{-1}$. Although we cannot exclude that …
We study the interstellar medium in a sample of 27 high-redshift quasar host galaxies at z>6, using the [CII] 158um emission line and the underlying dust continuum observed at ~1kpc resolution with ALMA. By performing uv-plane spectral stacking of both the high and low spatial resolution data, we investigate the spatial and velocity extent of gas, and the size of the dust-emitting regions. We find that the average surface brightness profile of both the [CII] and the dust continuum emission can be described by a steep component within a radius of 2kpc, and a shallower component with a scale len…
The Lya line in the UV and the [CII] line in the FIR are widely used tools to identify galaxies and to obtain insights into ISM properties in the early Universe. By combining data obtained with ALMA in band 7 at ~ 320 GHz as part of the ALMA Large Program to INvestigate [CII] at Early Times (ALPINE) with spectroscopic data from DEIMOS at Keck, VIMOS and FORS2 at the VLT, we assembled a unique sample of 53 main-sequence star-forming galaxies at 4.4 < z < 6 in which we detect both the Lya line and the [CII]. We used [CII], observed with ALMA, as a tracer of the systemic velocity of the galaxies,…
High-redshift observations are often biased towards massive and bright galaxies that are not necessarily representative of the full population. In order to accurately study galaxy evolution and mass assembly at these redshifts, observations of ``normal'' main sequence galaxies are required. Here we present Atacama Large Millimeter/Submillimeter Array (ALMA) 0.3" resolution observations of the [CII] emission line at 158$μ$m of HZ7, a main sequence galaxy at $z=5.25$. Comparing to archival rest-frame UV observations taken by the Hubble Space Telescope (HST), we find strong evidence of the existe…
We present new Atacama Large Millimeter/Submillimeter Array (ALMA) observations of the [CII] 158 $μ$m transition and the dust continuum in HZ4, a typical star-forming galaxy when the Universe was only $\sim1$ Gyr old ($z\approx5.5$). Our high $\approx0.3$'' spatial resolution allow us to study the relationships between [CII] line emission, star formation rate (SFR), and far-infrared (FIR) emission on spatial scales of $\sim2$ kpc. In the central $\sim$4 kpc of HZ4, the [CII]/FIR ratio is $\sim3\times10^{-3}$ on global scales as well as on spatially-resolved scales of $\sim$2 kpc, comparable to…
We present spatially-resolved morphological properties of [CII] 158 $μ$m, [OIII] 88 $μ$m, dust, and rest-frame ultraviolet (UV) continuum emission for A1689-zD1, a strongly lensed, sub-L* galaxy at $z=7.13$, by utilizing deep Atacama Large Millimeter/submillimeter Array (ALMA) and Hubble Space Telescope (HST) observations. While the [OIII] line and UV continuum are compact, the [CII] line is extended up to a radius of $r \sim 12$ kpc. Using multi-band rest-frame far-infrared (FIR) continuum data ranging from 52-400 $μ$m, we find an average dust temperature and emissivity index of $T_{\rm dust}…
Widespread Extended [CII] Emission in High-Redshift Galaxies: Insights from the FIRE-2 Cosmological Zoom-in Simulations
California Institute of Technology（加州理工学院）；CIERA and Department of Physics and Astronomy, Northwestern University（西北大学 CIERA 与物理和天文系）；IPAC, California Institute of Technology（加州理工学院 IPAC）；Department of Physics and Astronomy, University of Pennsylvania（宾夕法尼亚大学物理和天文系）
We present a comparison of the interstellar medium traced by [CII] (ALMA), and ionised halo gas traced by Lya (MUSE), in and around QSO host galaxies at z~6. To date, 18 QSOs at this redshift have been studied with both MUSE and high-resolution ALMA imaging; of these, 8 objects display a Lya halo. Using datacubes matched in velocity resolution, we compare and contrast the spatial and kinematic information of the Lya halos and the host galaxies' [CII] (and dust-continuum) emission. We find that the Lya halos extend typically 3-30 times beyond the interstellar medium of the host galaxies. The ma…
We predict the three-dimensional intensity power spectrum (PS) of the [CII] 158$\,μ$m line throughout the epoch of (and post) reionization at redshifts from $\approx$ 3.5 to 8. We study the detectability of the PS in a line intensity mapping (LIM) survey with the Fred Young Submillimeter Telescope (FYST). We created mock [CII] tomographic scans in redshift bins at $z\approx$ 3.7, 4.3, 5.8, and 7.4 using the Illustris TNG300-1 $Λ$CDM simulation and adopting a relation between the star formation activity and the [CII] luminosity ($L_{[CII]}$) of galaxies. A star formation rate (SFR) was assigned…
The intensity mapping of the [CII] 157.7 $\rm μ$m fine-structure emission line represents an ideal experiment to probe star formation activity in galaxies, especially in those that are too faint to be individually detected. Here, we investigate the feasibility of such an experiment for $z > 5$ galaxies. We construct the $L_{\rm CII} - M_{\rm h}$ relation from observations and simulations, then generate mock [CII] intensity maps by applying this relation to halo catalogs built from large scale N-body simulations. Maps of the extragalactic far-infrared (FIR) continuum, referred to as "foreground…
Intense and extended CIII] emission suggests a strong outflow in JADES-GS-z14-0
Scuola Normale Superiore（高等师范学院）；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）；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）；Steward Observatory, University of Arizona（亚利桑那大学斯图尔德天文台）；Centro de Astrobiología (CAB), CSIC-INTA（西班牙国家航空航天技术研究所/西班牙国家研究委员会天体生物学中心）；Department of Physics, University of Oxford（牛津大学物理系）；Sorbonne Université, CNRS（索邦大学法国国家科学研究中心）
[Abridged] We present maps of the main cooling lines of the neutral atomic gas ([OI] at 63 and 145 micron and [CII] at 158 micron) and in the [OIII] 88 micron line of the starburst galaxy M82, carried out with the PACS spectrometer on board the Herschel satellite. By applying PDR modeling we derive maps of the main ISM physical parameters, including the [CII] optical depth, at unprecedented spatial resolution (~300 pc). We can clearly kinematically separate the disk from the outflow in all lines. The [CII] and [OI] distributions are consistent with PDR emission both in the disk and in the outf…
The [CII]158$μ$m line is one of the strongest far-infrared (FIR) lines and an important coolant in the interstellar medium of galaxies that is accessible out to high redshifts. The excitation of [CII] is complex and can best be studied in detail at low redshifts. Here we report the discovery of the highest global [CII] excess with respect to the FIR luminosity in the nearby AGN host galaxy HE1353-1917. This galaxy is exceptional among a sample of five targets because the AGN ionization cone and radio jet directly intercept the cold galactic disk. As a consequence, a massive multiphase gas outf…
We present predictions for galactic halo baryon fractions from cosmological hydrodynamic simulations with a well-constrained model for galactic outflows. Without outflows, halos contain roughly the cosmic fraction of baryons, slightly lowered at high masses owing to pressure support from hot gas. The star formation efficiency is large and increases monotonically to low masses, in disagreement with data. With outflows, the baryon fraction is increasingly suppressed in halos to lower masses. A Milky Way-sized halo at z=0 has about 60% of the cosmic fraction of baryons, so "missing" halo baryons …
Luminous red galaxies (LRGs) are the most massive galaxies at $z\sim 0.5$ and, by selection, have negligible star formation. These objects have halo masses between those of $L_{*}$ galaxies, whose circumgalactic media (CGM) are observed to have large masses of cold gas, and clusters of galaxies, which primarily contain hot gas. Here we report detections of strong and extended metal (CIII 977) and HI lines in the CGM of two LRGs. The CIII lines have equivalent widths of $\sim 1.8$ Å and $\sim 1.2$ Å , and velocity spreads of $\sim 796$ km s$^{-1}$ and $\sim 1245$ km s$^{-1}$, exceeding all such…
The physical state of the gas in the central 500 pc of NGC~5128 (the radio galaxy Centaurus A - Cen A), was investigated using the far-infrared fine-structure lines of carbon, oxygen, and nitrogen, as well as the CO(4-3) molecular line. The circumnuclear disk (CND) is traced by emission from dust and the neutral gas ([CI] and CO). A gas outflow with a line-of-sight velocity of 60 km/s is evident in both species. The center of the CND is bright in [OI], [OIII], and [CII]; [OI]63mu emission dominates that of [CII] even though it is absorbed with optical depths of 1.0-1.5. The outflow is well-tra…
We present new deep ALMA and HST/WFC3 observations of MASOSA and VR7, two luminous Ly$α$ emitters (LAEs) at $z=6.5$, for which the UV continuum level differ by a factor four. No IR dust continuum emission is detected in either, indicating little amounts of obscured star formation and/or high dust temperatures. MASOSA, with a UV luminosity M$_{1500}=-20.9$, compact size and very high Ly$α$ EW$_{0}\approx145$ A, is undetected in [CII] to a limit of L$_{\rm [CII]}<2.2\times10^7$ L$_{\odot}$ implying a metallicity $Z\lesssim0.07 Z_{\odot}$. Intriguingly, our HST data indicates a red UV slope $β=-1…
We present the first predictions for the $L_{\rm [CII]}$ - SFR relation and [CII] luminosity function (LF) in the Epoch of Reionization (EoR) based on cosmological hydrodynamics simulations using the SIMBA suite plus radiative transfer calculations via SÍGAME. The sample consists of 11,137 galaxies covering halo mass $\log M_{\rm halo}\in$[9, 12.4] $M_\odot$, star formation rate SFR$\in$[0.01, 330] $M_\odot$ yr$^{-1}$, and metallicity $<Z_{\rm gas}>_{\rm SFR}\in$[0.1, 0.9] $Z_\odot$. The simulated $L_{\rm [CII]}$-SFR relation is consistent with the range observed, but with a spread of $\simeq$…
We study the efficiency of galactic feedback in the early Universe by stacking the [C II] 158 um emission in a large sample of normal star-forming galaxies at 4 < z < 6 from the ALMA Large Program to INvestigate [C II] at Early times (ALPINE) survey. Searching for typical signatures of outflows in the high-velocity tails of the stacked [C II] profile, we observe (i) deviations from a single-component Gaussian model in the combined residuals and (ii) broad emission in the stacked [C II] spectrum, with velocities of |v|<~ 500 km/s. The significance of these features increases when stacking the s…
We present a series of hydrodynamic simulations of isolated galaxies with stellar mass of $10^{9} \, \rm{M}_{\odot}$. The models use a resolution of $750 \, \rm{M}_{\odot}$ per particle and include a treatment for the full non-equilibrium chemical evolution of ions and molecules (157 species in total), along with gas cooling rates computed self-consistently using the non-equilibrium abundances. We compare these to simulations evolved using cooling rates calculated assuming chemical (including ionisation) equilibrium, and we consider a wide range of metallicities and UV radiation fields, includ…
We compare simulations, including the Illustris simulations, to observations of CIV and CII absorption at z=2-4. These are the CIV column density distribution function in the column density range $10^{12} - 10^{15}$ cm$^{-2}$, the CIV equivalent width distribution at 0.1 - 2 Å, and the covering fractions and equivalent widths of CIV 1548 and CII 1337 around DLAs. In the context of the feedback models we investigate, all CIV observations favour the use of more energetic wind models, which are better able to enrich the gas surrounding halos. We propose two ways to achieve this; an increased wind…
We present velocities of galactic outflows in seven star-forming galaxies at $z=$5-6 with stellar masses of $M_* \sim10^{10.1}\ \rm{M_\odot}$. Although it is challenging to observationally determine the outflow velocities, we overcome this by using ALMA [CII]158 $μ$m emission lines for systemic velocities and deep Keck spectra with metal absorption lines for velocity profiles available to date. We construct a composite Keck spectrum of the galaxies at $z=$5-6 with the [CII]-systemic velocities, and fit outflow-line profiles to the SiII1260, CII1335, and SiIV1394,1403 absorption lines in the co…
We report the discovery of a 10 comoving Mpc-scale structure traced by massive submillimeter galaxies (SMGs) at z~4.6. These galaxies are selected from an emission line search of ALMA Band 7 observations targeting 184 luminous submillimeter sources ($S_{850μ{\rm m}}\geq$ 6.2 mJy) across 1.6 degrees$^2$ in the COSMOS field. We identify four [CII] emitting SMGs and two probable [CII] emitting SMG candidates at z=4.60-4.64 with velocity-integrated signal-to-noise ratio of SNR>8. Four of the six emitters are near-infrared blank SMGs. After excluding one SMG whose emission line is falling at the ed…
We present constrained radiative transfer calculations of Lyman Alpha (Lya) photons propagating through clumpy, dusty, large scale outflows, and explore whether we can quantitatively explain the Lya halos that have been observed around Lyman Break Galaxies. We construct phenomenological models of large-scale outflows which consist of cold clumps that are in pressure equilibrium with a constant-velocity hot wind. First we consider models in which the cold clumps are distributed symmetrically around the galaxy, and in which the clumps undergo a continuous acceleration in its 'circumgalactic' med…
The early universe hosted a large population of low-mass virialized "minihalos," that were not massive enough to form stars on their own. While most minihalos were photoevaporated by ionizing photons from star-forming galaxies, these galaxies also drove large outflows, which in some cases would have reached the minihalos in advance of ionization fronts. In the previous papers in this series, we carried out high-resolution, three-dimensional adaptive mesh refinement simulations of outflow-minihalo interactions that included non-equilibrium chemistry, radiative cooling, and turbulent mixing. We …
We report interferometric imaging of [CII] and OH emission toward the center of the galaxy protocluster associated with the z=5.3 submillimeter galaxy (SMG) AzTEC-3, using the Atacama Large (sub)Millimeter Array (ALMA). We detect strong [CII], OH, and rest-frame 157.7 um continuum emission toward the SMG. The [CII] emission is distributed over a scale of 3.9 kpc, implying a dynamical mass of 9.7 x 10^10 Msun, and a star formation rate (SFR) surface density of Sigma_SFR = 530 Msun/yr/kpc2. This suggests that AzTEC-3 forms stars at Sigma_SFR approaching the Eddington limit for radiation pressure…
We present velocity resolved SOFIA/upGREAT observations of [OI] and [CII] lines toward a Class I protostar, L1551 IRS 5, and its outflows. The SOFIA observations detect [OI] emission toward only the protostar and [CII] emission toward the protostar and the red-shifted outflow. The [OI] emission has a width of $\sim$100 km s$^{-1}$ only in the blue-shifted velocity, suggesting an origin in shocked gas. The [CII] lines are narrow, consistent with an origin in a photodissociation region. Differential dust extinction from the envelope due to the inclination of the outflows is the most likely cause…
The Herschel Space Observatory was used to observe ~ 120 pre-main-sequence stars in Taurus as part of the GASPS Open Time Key project. PACS was used to measure the continuum as well as several gas tracers such as [OI] 63 μm, [OI] 145 μm, [CII] 158 μm, OH, H2O and CO. The strongest line seen is [OI] at 63 μm. We find a clear correlation between the strength of the [OI] 63 μm line and the 63 μm continuum for disk sources. In outflow sources, the line emission can be up to 20 times stronger than in disk sources, suggesting that the line emission is dominated by the outflow. The tight correlation …
We present ALMA [CII] 158 $μ$m line and underlying far-infrared (FIR) continuum emission observations ($0''.70 \times 0''.56$ resolution) toward HSC J124353.93$+$010038.5 (J1243$+$0100) at $z = 7.07$, the only low-luminosity ($M_{\rm 1450} > -25$ mag) quasar currently known at $z > 7$. The FIR continuum is bright (1.52 mJy) and resolved with a total luminosity of $L_{\rm FIR} = 3.5 \times 10^{12}~L_\odot$. The spatially extended component is responsible for $\sim 40\%$ of the emission. The area-integrated [CII] spectrum shows a broad wing (${\rm FWHM} = 997$ km s$^{-1}$, $L_{\rm [CII]} = 1.2 \…
We present ALMA observations of a merging system at z ~ 4.57, observed as a part of the ALMA Large Program to INvestigate [CII] at Early times (ALPINE) survey. Combining ALMA [CII] 158 micron and far-infrared continuum data with multi-wavelength ancillary data we find that the system is composed of two massive (Mstar >~ 10^10 Msun) star-forming galaxies experiencing a major merger (stellar mass ratio r_mass ~ 0.9) at close spatial (~13 kpc; projected) and velocity (delta_v < 300 km/s) separations, and two additional faint narrow [CII]-emitting satellites. The overall system belongs to a larger…
Many theoretical models predict that quasar driven outflows account for the observed quenching of star formation in massive galaxies. There is growing observational evidence for quasar-launched massive outflows at z>6, while the details of outflow-host galaxy interaction remain obscure. In this paper, we study the feedback around the highest redshift quasar in the BlueTides simulation, the largest volume cosmological hydrodynamic simulation so far carried out. We present predictions for gas outflows around the brightest $z = 7.54$ quasar which hosts the most massive black hole in the simulatio…
We study stellar-halo formation using six Milky Way-mass galaxies in FIRE-2 cosmological zoom simulations. We find that $5-40\%$ of the outer ($50-300$ kpc) stellar halo in each system consists of $\textit{in-situ}$ stars that were born in outflows from the main galaxy. Outflow stars originate from gas accelerated by super-bubble winds, which can be compressed, cool, and form co-moving stars. The majority of these stars remain bound to the halo and fall back with orbital properties similar to the rest of the stellar halo at $z=0$.In the outer halo, outflow stars are more spatially homogeneous,…
Massive galaxy-scale outflows of gas are one of the most commonly-invoked mechanisms to regulate the growth and evolution of galaxies throughout the universe. While the gas in outflows spans a large range of temperatures and densities, the cold molecular phase is of particular interest because molecular outflows may be capable of suppressing star formation in galaxies by removing the star-forming gas. We have conducted the first survey of molecular outflows at z > 4, targeting 11 strongly-lensed dusty, star-forming galaxies (DSFGs) with high-resolution Atacama Large Millimeter Array (ALMA) obs…
We describe a physical model of the outflows produced as a result of gas accretion onto a black hole, and the resultant changes to star formation rates and efficiencies in galaxies, using the Radio-SAGE semi-analytic galaxy formation model. We show that the ratio of outflow rate to SFR of galaxies is mainly driven by black hole mass and virial halo mass, and show that the SFR is higher than the outflow rate at low black hole masses. The model consistently reproduces the observed evolution of star formation rate density from z = 6 to z = 0, as well as the trend of the stellar mass - halo mass r…
We combine constraints on the galaxy-dark matter connection with structural and dynamical scaling relations to investigate the angular momentum content of disc galaxies. For haloes with masses in the interval 10^{11.3} < M_vir/M_sun < 10^{12.7} we find that the galaxy spin parameters are independent of halo mass with <λ'_gal> = (J_gal/M_gal) / (\sqrt{2} R_vir V_vir) = 0.019^{+0.004}_{-0.003} (1sigma). This is significantly lower than for relaxed LCDM haloes, which have an average spin parameter <λ'_halo> = 0.031. The average ratio between the specific angular momentum of disk galaxies and thei…
We present zoom-in, AMR, high-resolution ($\simeq 30$ pc) simulations of high-redshift ($z \simeq 6$) galaxies with the aim of characterizing their internal properties and interstellar medium. Among other features, we adopt a star formation model based on a physically-sound molecular hydrogen prescription, and introduce a novel scheme for supernova feedback, stellar winds and dust-mediated radiation pressure. In the zoom-in simulation the target halo hosts "Dahlia", a galaxy with a stellar mass $M_*=1.6\times 10^{10}$M$_\odot$, representative of a typical $z\sim 6$ Lyman Break Galaxy. Dahlia h…
We present deep MUSE integral-field unit (IFU) spectroscopic observations of the giant (~150 x 80 kpc) Ly-alpha halo around the z=4.1 radio galaxy TNJ J1338-1942. This 9-hr observation maps the two-dimensional kinematics of the Ly-alpha emission across the halo. We identify two HI absorbers which are seen against the Ly-alpha emission, both of which cover the full 150 x 80 kpc extent of the halo and so have covering fractions ~1. The stronger and more blue-shifted absorber (dv~1200 km/s) has dynamics that mirror that of the underlying halo emission and we suggest that this high column material…
We study fundamental properties of isothermal, steady and spherically symmetric galactic outflow in the gravitational potential of a cold dark matter halo and a central super-massive black hole. We find that there are two transonic solutions having different properties: each solution is mainly produced by the dark matter halo and the super-massive black hole, respectively. Furthermore, we apply our model to the Sombrero galaxy. In this galaxy, Chandra X-ray observatory detected the diffuse hot gas as the trace of galactic outflows while the star-formation rate is low and the observed gas densi…
The BD+40\degree4124 region was observed with high angular and spectral resolution with the German heterodyne instrument GREAT in CO J = 13 \rightarrow 12 and [CII] on SOFIA. These observations show that the [CII] emission is very strong in the reflection nebula surrounding the young Herbig Ae/Be star BD+40\degree4124. A strip map over the nebula shows that the [CII] emission approximately coincides with the optical nebulosity. The strongest [CII] emission is centered on the B2 star and a deep spectrum shows that it has faint wings, which suggests that the ionized gas is expanding. We also see…
We present results of [CII]$\,158\,\rm{μm}$ emission line observations, and report the spectroscopic redshift confirmation of a strongly lensed ($μ\sim20$) star-forming galaxy, MACS0308-zD1 at $z=6.2078\pm0.0002$. The [CII] emission line is detected with a signal-to-noise ratio $>6$ within the rest-frame UV bright clump of the lensed galaxy (zD1.1) and exhibits multiple velocity components; the narrow [CII] has a velocity full-width-half-maximum (FWHM) of $110\pm20\,\rm{km/s}$, while broader [CII] is seen with an FWHM of $230\pm20\,\rm{km/s}$. The broader [CII] component is blueshifted ($-80\p…
