Near IR diffraction-limited integral-field SINFONI spectroscopy of the Circinus galaxy

Using the adaptive optics assisted near infrared integral field spectrometer SINFONI on the VLT, we have obtained observations of the Circinus galaxy on parsec scales. The morphologies of the H_2(1-0)S(1) 2.12um and Br_gamma 2.17um emission lines are only slightly different, but their velocity maps are similar and show a gradient along the major axis of the galaxy, consistent with rotation.Since V_rot/sigma is approximately 1 suggests that random motions are also important, it is likely that the lines arise in a rotating spheroid or thickened disk around the AGN. Comparing the Br_gamma flux to the stellar continuum indicates that the star formation in this region began almost 10^8 yr ago. We also detect the [SiVI] 1.96um,[AlIX] 2.04um and [CaVIII] 2.32um coronal lines. In all cases we observe a broad blue wing, indicating the presence of two or more components in the coronal line region. A correlation between the ionisation potential and the asymmetry of the profiles was found for these high excitation species.Comment: 6 pages, 5 figures, Submitted to the Proceedings of the IFS Workshop, Jul 4-8 2005, Durham, Englan

Baryons: What, When and Where?

We review the current state of empirical knowledge of the total budget of baryonic matter in the Universe as observed since the epoch of reionization. Our summary examines on three milestone redshifts since the reionization of H in the IGM, z = 3, 1, and 0, with emphasis on the endpoints. We review the observational techniques used to discover and characterize the phases of baryons. In the spirit of the meeting, the level is aimed at a diverse and non-expert audience and additional attention is given to describe how space missions expected to launch within the next decade will impact this scientific field.Comment: Proceedings Review for "Astrophysics in the Next Decade: JWST and Concurrent Facilities", ed. X. Tielens, 38 pages, 10 color figures. Revised to address comments from the communit

Mass distribution in the Galactic Center based on interferometric astrometry of multiple stellar orbits

Galaxie

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

Molecular gas and star formation in the host galaxy of the QSO I Zw 1

We have investigated the ISM of the I Zw 1 QSO host galaxy with Plateau de Bure mm-interferometry and high angular resolution near-infrared imaging spectroscopy. We have detected a circumnuclear gas ring of diameter #propor to#1.5'' (1.8 kpc) in its millimetric CO line emission and have mapped the disk and the spiral arms of the host galaxy in the "1"2CO(1-0) line at 115 GHz as well as in the H (1.64 #mu#m) and K (2.2 #mu#m) band. Combining our new mm- and NIR-data with available estimates of the radio- and far-infrared contributions to the nuclear emission, we find strong evidence for a nuclear starburst ring. A comparison to other sources with nuclear activity indicates that these rings may be a common phenomenon and contribute a large fraction of the central luminosity. Both the CO rotation curve as well as the NIR amd optical images are consistent with an inclination of (38#+-#5) . Using this we obtain a total dynamical mass of (3.9#+-#1.6) x 10"1"0 M_sun and a cold molecular gas mass of (7.5#+-#1.5) x 10"9 M_sun for the inner 3.9 kpc. With an estimate of the nuclear stellar contribution to the mass and light from NIR spectroscopy and assuming that the contribution of the HI gas to the overall mass of the inner 3.9 kpc is small we derive an N_H_2/I_C_O-conversion factor close to 2 x 10"2"0 cm"-"2 K"-"1 km"-"1 s found for molecular gas in our Galaxy and many nearby external galaxies. A comparison to broad band spectra of spiral galaxies, ellipticals and the nucleus and disk in NGC 7469 suggests bluer disk colors for I Zw 1, and that star formation in the host galaxy and the western companion of I Zw 1 is enhanced. This is also supported by a starburst analysis using all available data on the northwestern spiral arm. The presence of molecular material within the disk and on the arm indicates that at least in this region 12 kpc from the nucleus star formation, and not scattered light from the QSO nucleus, is responsible for the blue disk colors. (orig.)Available from TIB Hannover: RN 9303(431) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

The molecular gas in the circumnuclear region of Seyfert galaxies

Sub-arcsecond IRAM Plateau de Bure mm-interferometric observations of the "1"2CO (2-1) line emission in the Seyfert 1 NGC 3227 and the Seyfert 2 NGC 1068 have revealed complex kinematic systems in the inner 100 pc to 300 pc that are not consistent with pure circular motion in the host galaxies. Modeling of these kinematic systems with elliptical orbits in the plane of the host galaxy (representing gas motion in a bar potential) is a possible solution but does not reproduce all features observed. A better description of the complex kinematics is achieved by circular orbits which are tilted out of the plane of the host galaxy. This could indicate that the thin circumnuclear gas disk is wraped. In the case of NGC 1068 the warp model suggests that at a radius of #propor to# 70 pc, the gas disk is oriented edge-on providing material for the obscuration of the AGN nucleus. The position-velocity diagrams show rising rotation curves at r #<=# 13 pc and an indication for large enclosed masses of #>=# 2 x 10"7M_sun for NGC 3227 and #>=# 10"8M_sun for NGC 1068 within the central 25 pcSIGLEAvailable from TIB Hannover: RN 9303(470) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Kinematics and mass distributions for non-spherical deprojected Sérsic density profiles and applications to multi-component galactic systems

Galaxie

Kinematics and mass distributions for non-spherical deprojected Sérsic density profiles and applications to multi-component galactic systems

Using kinematics to decompose the mass profiles of galaxies, including the dark matter contribution, often requires parameterization of the baryonic mass distribution based on ancillary information. One such model choice is a deprojected Sérsic profile with an assumed intrinsic geometry. The case of flattened, deprojected Sérsic models has previously been applied to flattened bulges in local star-forming galaxies (SFGs), but can also be used to describe the thick, turbulent disks in distant SFGs. Here, we extend this previous work that derived density (ρ) and circular velocity (vcirc) curves by additionally calculating the spherically-enclosed 3D mass profiles (Msph). Using these profiles, we compared the projected and 3D mass distributions, quantified the differences between the projected and 3D half-mass radii (Re; r1/2, mass, 3D), and compiled virial coefficients relating vcirc(R) and Msph(< r = R) or Mtot. We quantified the differences between mass fraction estimators for multi-component systems, particularly for dark matter fractions (ratio of squared circular velocities versus ratio of spherically enclosed masses), and we considered the compound effects of measuring dark matter fractions at the projected versus 3D half-mass radii. While the fraction estimators produce only minor differences, using different aperture radius definitions can strongly impact the inferred dark matter fraction. As pressure support is important in analyses of gas kinematics (particularly, at high redshifts), we also calculated the self-consistent pressure support correction profiles, which generally predict less pressure support than for the self-gravitating disk case. These results have implications for comparisons between simulation and observational measurements, as well as for the interpretation of SFG kinematics at high redshifts. We have made a set of precomputed tables and the code to calculate the profiles publicly available

Most Submillimeter Galaxies are Major Mergers

We analyze subarcsecond resolution interferometric CO line data for 12 submillimeter-luminous (S_(850 μm) ≥ 5 mJy) galaxies with redshifts between 1 and 3, presenting new data for 4 of them. Morphologically and kinematically, most of the 12 systems appear to be major mergers. Five of them are well-resolved binary systems, and seven are compact or poorly resolved. Of the four binary systems for which mass measurements for both separate components can be made, all have mass ratios of 1:3 or closer. Furthermore, comparison of the ratio of compact to binary systems with that observed in local ULIRGs indicates that at least a significant fraction of the compact submillimeter-luminous galaxies (SMGs) must also be late-stage mergers. In addition, the dynamical and gas masses we derive are most consistent with the lower end of the range of stellar masses published for these systems, favoring cosmological models in which SMGs result from mergers. These results all point to the same conclusion that most of the bright SMGs with L_(IR) ≳ 5 × 10^(12) L_☉ are likely major mergers

Determining subparsec supermassive black hole binary orbits with infrared interferometry

Galaxie