- ID:
- ivo://CDS.VizieR/J/A+A/658/A104
- Title:
- HL Tau SO2 14(0-14)-13(1,13) datacube
- Short Name:
- J/A+A/658/A104
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Planet-forming disks are not isolated systems. Their interaction with the surrounding medium affects their mass budget and chemical content. In the context of the ALMA-DOT program, we obtained high-resolution maps of assorted lines from six disks that are still partly embedded in their natal envelope. In this work, we examine the SO and SO_2_ emission that is detected from four sources: DG Tau, HL Tau, IRAS 04302+2247, and T Tau. The comparison with CO, HCO^+^, and CS maps reveals that the SO and SO_2_ emission originates at the intersection between extended streamers and the planet-forming disk. Two targets, DG Tau and HL Tau, offers clear cases of inflowing material inducing an accretion shock on the disk material. The measured rotational temperatures and radial velocities are consistent with this view. In contrast to younger Class 0 sources, these shocks are confined to the specific disk region impacted by the streamer. In HL Tau, the known accreting streamer induces a shock in the disk outskirt, and the released SO and SO_2_ molecules spiral toward the star in a few hundreds years. These results suggest that shocks induced by late accreting material may be common in the disks of young star-forming regions with possible consequences on the chemical composition and mass content of the disk. They also highlight the importance of SO and SO_2_ line observations to probe accretion shocks from a larger sample.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/122/1289
- Title:
- H magnitude and radial velocities of A1644
- Short Name:
- J/AJ/122/1289
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We discuss H-band (1.65{mu}m) near-infrared photometry of the central 9h^-2^Mpc^2^ of Abell 1644 (A1644) to a limiting M_H_~M*_H_+3 (throughout this paper H_0_=100h*km/s/Mpc). here are 861 galaxies in the photometric survey region. We also measured radial velocities of 155 galaxies; 141 of these are cluster members within 2.44h^-1^Mpc of the cluster center.
- ID:
- ivo://CDS.VizieR/J/ApJS/96/123
- Title:
- H-magnitudes of spiral galaxies
- Short Name:
- J/ApJS/96/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The H-magnitude aperture data published by the Aaronson et al. collaboration (See references) over a 10 year period is collected into a homogeneous data set of 1731 observations of 665 galaxies. Ninety-six percent of these galaxies have isophotal diameters and axial ratios determined by the Third Reference Catalogue of Bright Galaxies (RC3; de Vaucouleurs et al., 1991, Cat. <VII/155>), the most self-consistent set of optical data currently available. The precepts governing the optical data in the RC3 are systematically different from those of the Second Reference Catalogue (de Vaucouleurs, de Vaucouleurs, & Corwin 1976, Cat .<VII/112>), which were used by Aaronson et al. for their original analyses of galaxy peculiar motions. This in turn leads to systematic differences in growth curves and fiducial H-magnitudes, prompting the present recalibration of the near-infrared Tully-Fisher relationship. New optically normalized H-magnitude growth curves are defined for galaxies of types S0 to Im, from which new values of fiducial H-magnitude, H^g^_-0.5_, are measured for the 665 galaxies. A series of internal tests show that these four standard growth curves are defined to an accuracy of 0.05mag over the interval 1.5<=log(A/D_g_)<=-0.2. Comparisons with the Aaronson et al. values of diameters, axial ratios, and fiducial H-magnitudes show the expected differences, given the different definitions of these parameters. The values of H^g^_-0.5_ are assigned quality indices: a quality value of 1 indicates an accuracy of less than 0.2mag, quality 2 indicates an accuracy of 0.2-0.35mag, and quality 3 indicates an accuracy of more than 0.35mag. Revised values of corrected H I velocity widths are also given, based on the new set of axial ratios defined by the RC3.
- ID:
- ivo://CDS.VizieR/J/ApJ/769/82
- Title:
- H_2_ masses in a broad sample of galaxies
- Short Name:
- J/ApJ/769/82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To assess how external factors such as local interactions and fresh gas accretion influence the global interstellar medium of galaxies, we analyze the relationship between recent enhancements of central star formation and total molecular-to-atomic (H_2_/HI) gas ratios, using a broad sample of field galaxies spanning early-to-late type morphologies, stellar masses of 10^7.2^-10^11.2^M_{sun}_, and diverse stages of evolution. We find that galaxies occupy several loci in a "fueling diagram" that plots H_2_/HI ratio versus mass-corrected blue-centeredness, a metric tracing the degree to which galaxies have bluer centers than the average galaxy at their stellar mass. Spiral galaxies of all stellar masses show a positive correlation between H_2_/HI ratio and mass-corrected blue-centeredness. When combined with previous results linking mass-corrected blue-centeredness to external perturbations, this correlation suggests a systematic link between local galaxy interactions and molecular gas inflow/replenishment. Intriguingly, E/S0 galaxies show a more complex picture: some follow the same correlation, some are quenched, and a distinct population of blue-sequence E/S0 galaxies (with masses below key scales associated with transitions in gas richness) defines a separate loop in the fueling diagram. This population appears to be composed of low-mass merger remnants currently in late- or post-starburst states, in which the burst first consumes the H_2_ while the galaxy center keeps getting bluer, then exhausts the H_2_, at which point the burst population reddens as it ages. Multiple lines of evidence suggest connected evolutionary sequences in the fueling diagram. In particular, tracking total gas-to-stellar mass ratios within the fueling diagram provides evidence of fresh gas accretion onto low-mass E/S0s emerging from their central starburst episodes. Drawing on a comprehensive literature search, we suggest that virtually all galaxies follow the same evolutionary patterns found in our broad sample.
- ID:
- ivo://CDS.VizieR/J/A+A/637/A40
- Title:
- HMSCs classification and physical parameters
- Short Name:
- J/A+A/637/A40
- Date:
- 07 Dec 2021 10:47:33
- Publisher:
- CDS
- Description:
- The role of ionization feedback on high-mass (>8M_{sun}_) star formation is still highly debated. Questions remain concerning the presence of nearby HII regions changes the properties of early high-mass star formation and whether H ii regions promote or inhibit the formation of high-mass stars. To characterize the role of HII regions on the formation of high-mass stars, we study the properties of a sample of candidates high-mass starless clumps (HMSCs), of which about 90% have masses larger than 100 Msun. These high-mass objects probably represent the earliest stages of high-mass star formation; we search if (and how) their properties are modified by the presence of an HII region. We took advantage of the recently published catalog of HMSC candidates. By cross matching the HMSCs and HII regions, we classified HMSCs into three categories: 1) The HMSCs associated with HII regions both in the position in the projected plane of the sky and in velocity; 2) HMSCs associated in the plane of the sky, but not in velocity; and 3) HMSCs far away from any HII regions in the projected sky plane. We carried out comparisons between associated and non-associated HMSCs based on statistical analyses of multiwavelength data from infrared to radio. We show that there are systematic differences of the properties of HMSCs in different environments. Statistical analyses suggest that HMSCs associated with HII regions are warmer, more luminous, more centrally-peaked and turbulent. We also clearly show, for the first time, that the ratio of bolometric luminosity to envelope mass of HMSCs (L/M) could not be a reliable evolutionary probe for early massive star formation due to the external heating effects of the HII regions. We show HMSCs associated with HII regions present statistically significant differences from HMSCs far away from HII regions, especially for dust temperature and L/M. More centrally peaked and turbulent properties of HMSCs associated with HII regions may promote the formation of high-mass stars by limiting fragmentation. High-resolution interferometric surveys toward HMSCs are crucial to reveal how HII regions impact the star formation process inside HMSCs.
6436. HMXBs in nearby galaxies
- ID:
- ivo://CDS.VizieR/J/MNRAS/419/2095
- Title:
- HMXBs in nearby galaxies
- Short Name:
- J/MNRAS/419/2095
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on a homogeneous set of X-ray, infrared and ultraviolet observations from Chandra, Spitzer, GALEX and 2MASS archives, we study populations of high-mass X-ray binaries (HMXBs) in a sample of 29 nearby star-forming galaxies and their relation with the star formation rate (SFR). In agreement with previous results, we find that HMXBs are a good tracer of the recent star formation activity in the host galaxy and their collective luminosity and number scale with the SFR, in particular, LX~~2.6x10^39^SFR. However, the scaling relations still bear a rather large dispersion of rms~0.4dex, which we believe is of a physical origin. We present the catalog of 1057 X-ray sources detected within the D25 ellipse for galaxies of our sample and construct the average X-ray luminosity function (XLF) of HMXBs with substantially improved statistical accuracy and better control of systematic effects than achieved in previous studies. The XLF follows a power law with slope of 1.6 in the log(LX)~35-40 luminosity range with a moderately significant evidence for a break or cut-off at LX~10^40^erg/s. As before, we did not find any features at the Eddington limit for a neutron star or a stellar mass black hole. We discuss implications of our results for the theory of binary evolution. In particular we estimate the fraction of compact objects that once upon their lifetime experienced an X-ray active phase powered by accretion from a high mass companion and obtain a rather large number, fX~0.2x(0.1Myr/{tau}x) ({tau}x is the life time of the X-ray active phase). This is about 4 orders of magnitude more frequent than in LMXBs. We also derive constrains on the mass distribution of the secondary star in HMXBs.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/3652
- Title:
- H narrow-band imaging of XMMU J2235.3-2557
- Short Name:
- J/MNRAS/423/3652
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an extended narrow-band H{alpha} study of the massive galaxy cluster XMMU J2235.3-2557 at z=1.39. This paper represents a follow-up study to our previous investigation of star formation in the cluster centre, extending our analysis out to a projected cluster radius of 1.5Mpc. Using the Near InfraRed Imager and Spectrograph on Gemini North Telescope we obtained deep H narrow-band imaging corresponding to the rest-frame wavelength of H{alpha} at the cluster's redshift. We identify a total of 163 potential cluster members in both pointings, excluding stars based on their near-infrared colours derived from VLT/HAWK-I imaging. Of these 163 objects 14 are spectroscopically confirmed cluster members, and 20 per cent are excess line emitters. We find no evidence of star formation activity within a radius of 200 kpc of the brightest cluster galaxy in the cluster core. Dust-corrected star formation rates (SFRs) of excess emitters outside this cluster quenching radius, R_Q_~200kpc, are on average <SFR>=2.7+/-1.0M_{sun}_/yr, but do not show evidence of increasing SFRs towards the extreme 1.5Mpc radius of the cluster. No individual cluster galaxy exceeds an SFR of 6M_{sun}_/yr. Massive galaxies (logM*/M_{sun}_>10.75) all have low specific SFRs (SSFRs, i.e. SFR per unit stellar mass). At fixed stellar mass, galaxies in the cluster centre have lower SSFRs than the rest of the cluster galaxies, which in turn have lower SSFRs than field galaxies at the same redshift by a factor of a few to 10. For the first time we can demonstrate through measurements of individual SFRs that already at very early epochs (at an age of the Universe of ~4.5Gyr) the suppression of star formation is an effect of the cluster environment which persists at fixed galaxy stellar mass.
- ID:
- ivo://CDS.VizieR/J/MNRAS/411/2009
- Title:
- H narrow-band imaging of XMMU J2235.3-2557
- Short Name:
- J/MNRAS/411/2009
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of a narrow-band photometric study of the massive galaxy cluster XMMU J2235.3-2557 at z=1.39. We obtained deep H narrow-band imaging with the Near InfraRed Imager and Spectrometer on Gemini North, corresponding to H{alpha} emission at the cluster's redshift. Our sample consists of 82 galaxies within a radius of ~500kpc, 10 of which are spectroscopically confirmed cluster members. 16 galaxies are identified as excess line-emitters.
- ID:
- ivo://CDS.VizieR/J/A+A/361/1079
- Title:
- HNCO in massive galactic dense cores
- Short Name:
- J/A+A/361/1079
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We surveyed 81 dense molecular cores associated with regions of massive star formation and Sgr A in the J_(K_-1_K_1_)=5_(05)-4_(04)_ and 10_(010)-9_(09)_ lines of HNCO. Line emission was detected towards 57 objects. Selected subsamples were also observed in the 1_(01)-0_(00)_, 4_(04)-3_(03)_, 7_(07)-6_(06)_, 15_(015)-14_(014)_, 16_(016)-15_(015)_ and 21_(021)-20_(020)_ lines, covering a frequency range from 22 to 461 GHz. HNCO lines from the K_(-1)=2,3 ladders were detected in several sources. Towards Orion-KL, K_(-1)=5 transitions with upper state energies E_u/k~1100 and 1300K could be observed. The tables contain the source lists and the results of these SEST observations.
- ID:
- ivo://CDS.VizieR/J/A+A/391/967
- Title:
- H2O and SiO masers in the Galactic center
- Short Name:
- J/A+A/391/967
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed targeted surveys for 22GHz H_2_O and 43GHz SiO maser emission in Galactic center OH/IR stars using the Very Large Array. Some of the detections have been used in a previous paper to investigate the possibility of measuring milli-arcsecond accurate positions (to obtain stellar proper motions) in the Galactic center. Here we report on the detection of at least 25 H_2_O masers and 18 SiO masers associated with stars within 2{deg} and 15' of Sgr A*, respectively. This survey has more than doubled the total number of proper motion candidates to at least about 50 stellar objects.