- ID:
- ivo://CDS.VizieR/J/ApJ/866/139
- Title:
- Knots in the deep [FeII]+[SiI] image of the SNR Cas A
- Short Name:
- J/ApJ/866/139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a long-exposure (~10hr), narrowband image of the supernova (SN) remnant Cassiopeia A (Cas A) centered at 1.644{mu}m emission. The passband contains [FeII] 1.644{mu}m and [SiI] 1.645{mu}m lines, and our "deep [FeII]+[SiI] image" provides an unprecedented panoramic view of Cas A, showing both shocked and unshocked SN ejecta, together with shocked circumstellar medium at subarcsecond (~0.7" or 0.012pc) resolution. The diffuse emission from the unshocked SN ejecta has a form of clumps, filaments, and arcs, and their spatial distribution correlates well with that of the Spitzer [SiII] infrared emission, suggesting that the emission is likely due to [SiI] not [FeII] as in shocked material. The structure of the optically invisible western area of Cas A is clearly seen for the first time. The area is filled with many quasi-stationary flocculi (QSFs) and fragments of the disrupted ejecta shell. We identified 309 knots in the deep [FeII]+[SiI] image and classified them into QSFs and fast-moving knots (FMKs). The comparison with previous optical plates indicates that the lifetime of most QSFs is >~60yr. The total H+He mass of QSFs is ~0.23M_{sun}_, implying that the mass fraction of dense clumps in the progenitor's mass ejection immediately prior to the SN explosion is about 4%-6%. FMKs in the deep [FeII]+[SiI] image mostly correspond to S-rich ejecta knots in optical studies, while those outside the southeastern disrupted ejecta shell appear Fe-rich. The mass of the [FeII] line emitting, shocked dense Fe ejecta is ~3x10^-5^M_{sun}_.
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Search Results
- ID:
- ivo://koa.ipac/TAP
- Title:
- KOA Table Access Protocol (TAP) Service
- Short Name:
- KOA TAP
- Date:
- 16 Nov 2021 20:00:00
- Publisher:
- Keck Observatory Archive
- Description:
- The KOA TAP service is a Python implementation of the TAP protocol using open-source and extensible code. It offers discovery and access to all instruments whose data are archived at KOA.
- ID:
- ivo://CDS.VizieR/J/AJ/161/45
- Title:
- KODIAQ DR3: 727 quasars (01.<zem<6.4) with ESI
- Short Name:
- J/AJ/161/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present and make publicly available the third data release (DR3) of the Keck Observatory Database of Ionized Absorption toward Quasars (KODIAQ) survey. KODIAQ DR3 consists of a fully reduced sample of 727 quasars at 0.1<zem<6.4 observed with the Echellette Sepctrograph and Imager at moderate resolution (4000<~R<~10000). DR3 contains 872 spectra available in flux calibrated form, representing a sum total exposure time of ~2.8 megaseconds. These coadded spectra arise from a total of 2753 individual exposures of quasars taken from the Keck Observatory Archive (KOA) in raw form and uniformly processed using a data reduction package made available through the XIDL distribution. DR3 is publicly available to the community, housed as a higher level science product at the KOA and in the igmspec database.
- ID:
- ivo://CDS.VizieR/J/AJ/109/709
- Title:
- K survey of Ori A molecular cloud
- Short Name:
- J/AJ/109/709
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a 2.2{mu}m (limiting K about 14.5mag) survey of the northern portion of the Orion A molecular cloud. A total of 3548 sources were detected in the 1472arcmin^2^ area surveyed. We detect clustering of 2.2{mu}m sources at the locations of the Trapezium and OMC-2. No strict boundaries for these clusters could be drawn from our data because we find that the entire region surveyed shows an overabundance of sources when compared with background field levels. We find that the form of the observed K luminosity function (KLF) of stars near the Trapezium is consistent with that predicted from a Miller and Scalo (ApJS 41, 513 (1979) IMF, if the age of the cluster is about 1Myr. Away from the Trapezium and the OMC-2, the KLF of stars suggests that either this population contains more low mass stars or that it is older than the Trapezium stars. The survey was carried out using the Ohio State InfraRed Imaging System (OSIRIS) 256x256 HgCdTe array on the Perkins 1.8m telescope in November 1992. In survey mode OSIRIS provides a spatial resolution of 1.50arcsec/pixel; the total field of view of the camera is 6.4arcmin. The telescope was rastered on 4.2arcmin steps to produce a mosaic approximately 39x39arcmin, centered near the Trapezium. A total of 81 K-band images were obtained, each with an exposure time about 3s.
- ID:
- ivo://CDS.VizieR/J/ApJ/842/120
- Title:
- Large spectrosc. survey of Palomar 5 stellar stream
- Short Name:
- J/ApJ/842/120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two spectroscopic surveys of the tidal stellar stream of the Palomar 5 globular cluster undertaken with the VLT/FLAMES and AAT/AAOmega instruments. We use these data in conjunction with photometric data presented in the previous contribution in this series to classify the survey stars in terms of their probability of belonging to the Palomar 5 stellar stream. We find that high-probability candidates are only found in a very narrow spatial interval surrounding the locus of the stream on the sky. PanSTARRS RRLyrae stars in this region of the sky are also distributed in a similar manner. The absence of significant "fanning" of this stellar stream confirms that Palomar 5 does not follow a chaotic orbit. Previous studies have found that Palomar 5 is largely devoid of low-mass stars, and we show that this is true also of the stellar populations along the trailing arm out to 6{deg}. Within this region, which contains 73% of the detected stars, the population is statistically identical to the core, implying that the ejection of the low-mass stars occurred before the formation of the stream. We also present an updated structural model fit to the bound remnant, which yields a total mass of 4297+/-98M_{sun}_ and a tidal radius 0.145+/-0.009kpc. We estimate the mass of the observed system including the stream to be 12200+/-400M_{sun}_, and the initial mass to have been ~47000+/-1500M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A10
- Title:
- LARS XI. Turbulence Driven Lyman Alpha Escape
- Short Name:
- J/A+A/644/A10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the global dust and (molecular) gas content in the Lyman Alpha Reference Sample (LARS), i.e. 14 local star-forming galaxies. We characterize their interstellar medium and relate newly derived properties to quantities relevant for Ly{alpha} escape. We observed LARS galaxies with Herschel/PACS, SOFIA/FIFI-LS, the IRAM 30m telescope and APEX, targeting far-infrared (FIR) continuum and emission lines of [CII]158um, [OI]63um, [OIII]88um and low-J CO lines. Using Bayesian methods we derive dust model parameters and estimate total gas masses for all LARS galaxies, taking into account a metallicity-dependent gas-to-dust ratio. Star formation rates were estimated from FIR, [CII]158um and [OI]63um luminosities. LARS covers a wide dynamic range in the derived properties, with FIR-based star formation rates from ~0.5-100M_{sun}/yr, gas fractions between ~15-80% and gas depletion times ranging from a few hundred Myr up to more than 10Gyr. The distribution of LARS galaxies in the {SIGMA}_gas_ vs. {SIGMA}_SFR_ (Kennicutt-Schmidt plane) is thus quite heterogeneous. However, we find that LARS galaxies with the longest gas depletion times, i.e. relatively high gas surface densities ({SIGMA}_gas_) and low star formation rate densities ({SIGMA}_SFR_ have by far the highest Ly{alpha} escape fraction. A strong [Math Processing Error]linear relation is found between Ly{alpha} escape fraction and the total gas (HI+H_2_) depletion time. We argue that the Ly{alpha} escape in those galaxies is driven by turbulence in the star-forming gas that shifts the Ly{alpha} photons out of resonance close to the places where they originate. We further report on an extreme [CII]158um excess in LARS 5, corresponding to ~14+/-3% of the FIR luminosity, i.e. the most extreme [CII]-to-FIR ratio observed in a non-AGN galaxy to date.
- ID:
- ivo://CDS.VizieR/J/A+A/425/489
- Title:
- Late-type stars in the inner Milky Way
- Short Name:
- J/A+A/425/489
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a narrow-band infrared imaging survey of a narrow strip (12' wide) around the Galactic equator between 6{deg} and 21{deg} of galactic longitude aimed at detecting field stars with strong CO absorption, mainly late-type giants and supergiants. Our observations include follow-up low resolution spectroscopy (R=980) of 191 selected candidates in the H and K bands.
- ID:
- ivo://CDS.VizieR/J/ApJ/868/129
- Title:
- Lensing analysis in Abell 370
- Short Name:
- J/ApJ/868/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new gravitational lens model of the Hubble Frontier Fields cluster Abell 370 (z=0.375) using imaging and spectroscopy from Hubble Space Telescope and ground-based spectroscopy. We combine constraints from a catalog of 909 weakly lensed galaxies and 39 multiply imaged sources comprised of 114 multiple images, including a system of multiply imaged candidates at z=7.84+/-0.02, to obtain a best-fit mass distribution using the cluster lens modeling code strong and weak lensing united. As the only analysis of A370 using strong and weak lensing constraints from Hubble Frontier Fields (HFF) data, our method provides an independent check of assumptions on the mass distribution used in other methods. Convergence, shear, and magnification maps are made publicly available through the HFF website (http://www.stsci.edu/hst/campaigns/frontier-fields). We find that the model we produce is similar to models produced by other groups, with some exceptions due to the differences in lensing code methodology. In an effort to study how our total projected mass distribution traces light, we measure the stellar mass density distribution using Spitzer/Infrared array camera imaging. Comparing our total mass density to our stellar mass density in a radius of 0.3Mpc, we find a mean projected stellar to total mass ratio of <f*>=0.011+/-0.003 (stat.) using the diet Salpeter initial mass function. This value is in general agreement with independent measurements of <f*> in clusters of similar total mass and redshift.
- ID:
- ivo://CDS.VizieR/J/A+A/598/A79
- Title:
- 10 Leo in YJ, H, K, L and M bands spectra
- Short Name:
- J/A+A/598/A79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High resolution stellar spectral atlases are valuable resources to astronomy. They are rare in the 1-5{mu}m region for historical reasons, but once available, high resolution atlases in this part of the spectrum will aid the study of a wide range of astrophysical phenomena. The aim of the CRIRES-POP project is to produce a high resolution near-infrared spectral library of stars across the H-R diagram. The aim of this paper is to present the fully reduced spectrum of the K giant 10 Leo that will form the basis of the first atlas within the CRIRES-POP library, to provide a full description of the data reduction processes involved, and to provide an update on the CRIRES-POP project. All CRIRES-POP targets were observed with almost 200 different observational settings of CRIRES on the ESO Very Large Telescope, resulting in a basically complete coverage of its spectral range as accessible from the ground. We reduced the 10 Leo spectra with the CRIRES pipeline, corrected the wavelength solution and removed telluric absorption with Molecfit, then resampled the spectra to a common wavelength scale, shifted to rest wavelengths, flux normalised, and median combined them into one final data product. We present the fully reduced, high resolution, near-infrared spectrum of 10 Leo. This is also the first complete spectrum from the CRIRES instrument. The spectrum is available online. The first CRIRES-POP spectrum has exceeded our quality expectations and will form the centre of a state-of-the-art stellar atlas. This first CRIRES-POP atlas will soon be available, and further atlases will follow. All CRIRES-POP data products will be freely and publicly available online.
- ID:
- ivo://CDS.VizieR/J/A+A/593/A112
- Title:
- LHA 120-S 73 optical and NIR spectra
- Short Name:
- J/A+A/593/A112
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- B[e] supergiants are evolved massive stars, enshrouded in a dense wind and surrounded by a molecular and dusty disk. The mechanisms that drive phases of enhanced mass loss and mass ejections, responsible for the shaping of the circumstellar material of these objects, are still unclear. We aim to improve our knowledge on the structure and dynamics of the circumstellar disk of the Large Magellanic Cloud B[e] supergiant LHA 120-S 73. High-resolution optical and near-infrared spectroscopic data were obtained over a period of 16 and 7 yr, respectively. The spectra cover the diagnostic emission lines from [CaII] and [OI], as well as the CO bands. These features trace the disk at different distances from the star. We analyzed the kinematics of the individual emission regions by modeling their emission profiles. A low-resolution mid-infrared spectrum was obtained as well, which provides information on the composition of the dusty disk.
