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1041. HET Massive Galaxy Survey (HETMGS)
ID:
ivo://CDS.VizieR/J/ApJS/218/10
Title:
HET Massive Galaxy Survey (HETMGS)
Short Name:
J/ApJS/218/10
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted an optical long-slit spectroscopic survey of 1022 galaxies using the 10m Hobby-Eberly Telescope (HET) at McDonald Observatory. The main goal of the HET Massive Galaxy Survey (HETMGS) is to find nearby galaxies that are suitable for black hole mass measurements. In order to measure accurately the black hole mass, one should kinematically resolve the region where the black hole dominates the gravitational potential. For most galaxies, this region is much less than an arcsecond. Thus, black hole masses are best measured in nearby galaxies with telescopes that obtain high spatial resolution. The HETMGS focuses on those galaxies predicted to have the largest sphere-of-influence, based on published stellar velocity dispersions or the galaxy fundamental plane. To ensure coverage over galaxy types, the survey targets those galaxies across a face-on projection of the fundamental plane. We present the sample selection and resulting data products from the long-slit observations, including central stellar kinematics and emission line ratios. The full data set, including spectra and resolved kinematics, is available online. Additionally, we show that the current crop of black hole masses are highly biased toward dense galaxies and that especially large disks and low dispersion galaxies are under-represented. This survey provides the necessary groundwork for future systematic black hole mass measurement campaigns.
1042. HH 529 spectroscopy
ID:
ivo://CDS.VizieR/J/ApJ/644/1006
Title:
HH 529 spectroscopy
Short Name:
J/ApJ/644/1006
Date:
21 Oct 2021
Publisher:
CDS
Description:
The spectra of Herbig-Haro objects are usually characteristic of ionization and excitation in shock-heated gas, whether an internal shock in an unsteady outflow or a bow shock interface with the interstellar medium. We examine the easternmost shock the leading optically visible shock of a Herbig-Haro outflow (HH 529) seen projected on the face of the Orion Nebula, using deep optical echelle spectroscopy, showing that the spectrum of this gas is consistent with photoionization by theta^1^ Ori C. By modeling the emission lines, we determine a gas-phase abundance of Fe that is consistent with the depleted (relative to solar) abundance found in the Orion nebula-evidence for the presence of dust in the nebula and therefore in the Herbig-Haro outflow. The spectrum also allows for the calculation of temperature fluctuations, t^2^, in the nebula and the shock. These fluctuations have been used to explain discrepancies between abundances obtained from recombination lines versus those obtained from collisionally excited lines, although to date there has not been a robust theory for how such large fluctuations (t^2^>0.02) can be.
1043. HI and OVI absorbers in nearby Universe
ID:
ivo://CDS.VizieR/J/ApJS/182/378
Title:
HI and OVI absorbers in nearby Universe
Short Name:
J/ApJS/182/378
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyze intergalactic HI and OVI absorbers with {nu}<5000km/s in Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer spectra of 76 active galactic nuclei. The baryons traced by HI/OVI absorption are clearly associated with the extended surroundings of galaxies; for impact parameters <400kpc they are 2-4 times more numerous as those inside the galaxies. This large reservoir of matter likely plays a major role in galaxy evolution. We tabulate the fraction of absorbers having a galaxy of a given luminosity within a given impact parameter ({rho}) and velocity difference ({Delta}v), as well as the fraction of galaxies with an absorber closer than a given {rho} and {Delta}v. We identify possible "void absorbers" ({rho}>3Mpc to the nearest L_*_ galaxy), although at v<2500km/s all absorbers are within 1.5Mpc of an L>0.1L_*_ galaxy. The absorber properties depend on {rho}, but the relations are not simple correlations.
1044. HI data of galaxies from Kazarian's lists
ID:
ivo://CDS.VizieR/J/A+AS/126/471
Title:
HI data of galaxies from Kazarian's lists
Short Name:
J/A+AS/126/471
Date:
21 Oct 2021
Publisher:
CDS
Description:
The 21-cm neutral hydrogen line has been measured for the first time in 39 non-Seyfert type galaxies from Kazarian list, with the Nancay radiotelescope. The line profiles, widths at 20% and 50% of the peak intensity, radial velocities as well as total fluxes are presented. The values of radial velocity are in fairly good agreement with those obtained from optical spectra. The width values at 20% of the peak vary in wide range from 113km/s (KAZ 579) to 608km/s for KAZ 566. Nine of our objects remained undetected, whether their HI-flux was too faint, the integration time too short, or the frequency sighted wrong. However, for part of them, there were positive hint of detection. Comments on individual objects are given.
1045. Hidden population of AM CVns in the SDSS
ID:
ivo://CDS.VizieR/J/MNRAS/429/2143
Title:
Hidden population of AM CVns in the SDSS
Short Name:
J/MNRAS/429/2143
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the latest results from a spectroscopic survey designed to uncover the hidden population of AM Canum Venaticorum (AM CVn) binaries in the photometric database of the Sloan Digital Sky Survey (SDSS). We selected ~2000 candidates based on their photometric colours, a relatively small sample which is expected to contain the majority of all AM CVn binaries in the SDSS (expected to be ~50). We present two new candidate AM CVn binaries discovered using this strategy: SDSS J104325.08+563258.1 and SDSS J173047.59+554518.5. We also present spectra of 29 new cataclysmic variables, 23 DQ white dwarfs and 21 DZ white dwarfs discovered in this survey. The survey is now approximately 70 per cent complete, and the discovery of seven new AM CVn binaries indicates a lower space density than previously predicted. From the essentially complete g~19 sample, we derive an observed space density of (5+/-3)*10^-7^pc^-3^; this is lower than previous estimates by a factor of 3. The sample has been cross-matched with the GALEX All-Sky Imaging Survey database, and with Data Release 9 of the UKIRT (United Kingdom Infrared Telescope) Infrared Deep Sky Survey (UKIDSS). The addition of UV photometry allows new colour cuts to be applied, reducing the size of our sample to ~1100 objects. Optimising our followup should allow us to uncover the remaining AM CVn binaries present in the SDSS, providing the larger homogeneous sample required to more reliably estimate their space density.
1046. HIFI molecular line survey of SgrB2 (M)
ID:
ivo://CDS.VizieR/J/A+A/651/A9
Title:
HIFI molecular line survey of SgrB2 (M)
Short Name:
J/A+A/651/A9
Date:
22 Feb 2022
Publisher:
CDS
Description:
We present a full analysis of a broadband spectral line survey of Sagittarius B2 (Main), one of the most chemically rich regions in the Galaxy located within the giant molecular cloud complex Sgr B2 in the Central Molecular Zone. Our goal is to derive the molecular abundances and temperatures of the high-mass star-forming region Sgr B2(M) and thus its physical and astrochemical conditions. Sgr B2(M) was observed using the Heterodyne Instrument for the Far-Infrared (HIFI) on board the Herschel Space Observatory in a spectral line survey from 480 to 1907GHz at a spectral resolution of 1.1MHz, which provides one of the largest spectral coverages ever obtained toward this high-mass star-forming region in the submillimeter with high spectral resolution and includes frequencies >1THz that are unobservable from the ground. We modeled the molecular emission from the submillimeter to the far-infrared using the XCLASS program, which assumes local thermodynamic equilibrium (LTE). For each molecule, a quantitative description was determined taking all emission and absorption features of that species across the entire spectral range into account. Because of the wide frequency coverage, our models are constrained by transitions over an unprecedented range in excitation energy. Additionally, we derived velocity resolved ortho/para ratios for those molecules for which ortho and para resolved molecular parameters are available. Finally, the temperature and velocity distributions are analyzed and the derived abundances are compared with those obtained for Sgr B2(N) from a similar HIFI survey. A total of 92 isotopologues were identified, arising from 49 different molecules, ranging from free ions to complex organic compounds and originating from a variety of environments from the cold envelope to hot and dense gas within the cores. Sulfur dioxide, methanol, and water are the dominant contributors. Vibrationally excited HCN (v2=1) and HNC (v2=1) are detected as well. For the ortho/para ratios, we find deviations from the high temperature values between 37 and 180%. In total 14% of all lines remain unidentified. Compared to Sgr B2(N), we found less complex molecules such as CH_3_OCH_3_, CH_3_NH_2_, or NH_2_CHO, but more simple molecules such as CN, CCH, SO, and SO_2_. However some sulfur bearing molecules such as H_2_CS, CS, NS, and OCS are more abundant in N than in M. The derived molecular abundances can be used for comparison to other sources and for providing further constraints for astrochemical models.
1047. Hi-Gal sources distance determination
ID:
ivo://CDS.VizieR/J/A+A/526/A151
Title:
Hi-Gal sources distance determination
Short Name:
J/A+A/526/A151
Date:
21 Oct 2021
Publisher:
CDS
Description:
Hi-GAL, an open time key-project of the Herschel satellite, was awarded 343 hours observing time to carry out a 5-band photometric imaging survey at 70, 160, 250, 350, and 500um of a |b|<=1{deg} wide strip of the Milky Way Galactic plane in the longitude range -70{deg}<=l<=70{deg}. Two 2{deg}x2{deg} fields centred at l=30{deg} and l=59{deg} have been observed with the SPIRE and PACS photometric cameras in parallel mode during the Herschel science demonstration phase (SDP). From the images, compact sources are extracted for which the distance must be established in order to determine their physical properties. The aim of this paper is to present the distance determination strategy for the Hi-GAL compact sources. We illustrate this strategy for the two fields at l=30{deg} and l=59{deg}.
1048. High angular resolution spectroscopy of NGC 1277
ID:
ivo://CDS.VizieR/J/ApJ/817/2
Title:
High angular resolution spectroscopy of NGC 1277
Short Name:
J/ApJ/817/2
Date:
21 Oct 2021
Publisher:
CDS
Description:
The nearby lenticular galaxy NGC 1277 is thought to host one of the largest black holes known, however the black hole mass measurement is based on low spatial resolution spectroscopy. In this paper, we present Gemini Near-infrared Integral Field Spectrometer observations assisted by adaptive optics. We map out the galaxy's stellar kinematics within ~440pc of the nucleus with an angular resolution that allows us to probe well within the region where the potential from the black hole dominates. We find that the stellar velocity dispersion rises dramatically, reaching ~550km/s at the center. Through orbit-based, stellar-dynamical models we obtain a black hole mass of (4.9+/-1.6)x10^9^M_{sun}_ (1{sigma} uncertainties). Although the black hole mass measurement is smaller by a factor of ~3 compared to previous claims based on large-scale kinematics, NGC 1277 does indeed contain one of the most massive black holes detected to date, and the black hole mass is an order of magnitude larger than expectations from the empirical relation between black hole mass and galaxy luminosity. Given the galaxy's similarities to the higher redshift (z~2) massive quiescent galaxies, NGC 1277 could be a relic, passively evolving since that period. A population of local analogs to the higher redshift quiescent galaxies that also contain over-massive black holes may suggest that black hole growth precedes that of the host galaxy.
1049. High-dispersion spectra of nearby F-K stars
ID:
ivo://CDS.VizieR/J/PASJ/57/13
Title:
High-dispersion spectra of nearby F-K stars
Short Name:
J/PASJ/57/13
Date:
21 Oct 2021
Publisher:
CDS
Description:
Towards constructing a system of high-dispersion spectroscopic standard stars with well-established abundances, so that adequate reference stars of similar properties may be found for precise differential abundance studies of any near-solar type stars, we have collected high-resolution (R~70000) echelle spectra for 160 F-K dwarfs and subgiants of the solar neighborhood in three wavelength regions (5000-6200{AA}, 5800-7000{AA}, and 7600-8800{AA}) at Okayama Astrophysical Observatory. This spectra database is open to the public.
1050. High-dispersion spectrum of the PN DdDm 1
ID:
ivo://CDS.VizieR/J/ApJ/705/509
Title:
High-dispersion spectrum of the PN DdDm 1
Short Name:
J/ApJ/705/509
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the High Dispersion Spectrograph (HDS) at the Subaru Telescope, we secured the high-resolution line spectra in the 3600-7500{AA} wavelength range of the Galactic halo planetary nebula DdDm 1. We also analyzed the Hubble Space Telescope Faint Object Spectrograph data in the 1200-6730{AA} wavelength range. The diagnostic results indicate the electron temperatures of T_{epsilon}_~11000-14000K and the electron number densities of N_{epsilon}_~2000-10500cm^-3^. In spite of high gaseous temperatures, we have not detected high excitation lines, e.g., HeII. We derived abundance based on the ionic concentration of permitted and forbidden lines and the photoionization model. A comparison of the ionic concentrations from forbidden lines to recombination lines shows the abundance discrepancy between them. We tested various possibilities, e.g., temperature fluctuation and high-density blob components, to explain the discrepancy. The high-density components or density fluctuation might be partly responsible for the discrepancy. DdDm 1 shows a low carbon abundance that corresponds to metal-poor stars, [Fe/H]<=-1. Assuming a distance of 10kpc to DdDm 1, theoretical models suggest that the central star has T_eff_~39000K and L~2000-3000L_{sun}_. The relatively high gas temperatures appear to be caused by very low heavy elemental abundances or insufficient coolants in the shell gas. Its progenitor, born in an extremely carbon-poor environment as an initial mass of about 0.9M_{sun}_, had probably experienced only the first dredge-up.

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