- ID:
- ivo://irsa.ipac/Herschel/Catalog/Hi-GAL/Hi-GAL_500
- Title:
- Hi-GAL 500 micron Photometric Catalog
- Short Name:
- Hi-GAL_500
- Date:
- 01 Oct 2018 20:27:20
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- The Herschel infrared Galactic Plane Survey (Hi-GAL) covers the Galactic plane at five wavelengths from 70 to 500 microns. Hi-GAL DR1 is limited to the inner Milky Way in the longitude range +68d > l > -70d and latitude range 1d > b > -1d. The generation of the Hi-GAL photometric catalogs is discussed in detail in Molinari et al. (2016).
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- ID:
- ivo://CDS.VizieR/J/ApJ/772/45
- Title:
- Hi-GAL obs.: star formation in the third quadrant
- Short Name:
- J/ApJ/772/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first Herschel PACS and SPIRE photometric observations in a portion of the outer Galaxy (216.5{deg}<~l<~225.5{deg} and -2{deg}<~b<~0{deg}) as a part of the Hi-GAL survey. The maps between 70 and 500{mu}m, the derived column density and temperature maps, and the compact source catalog are presented. NANTEN CO(1-0) line observations are used to derive cloud kinematics and distances so that we can estimate distance-dependent physical parameters of the compact sources (cores and clumps) having a reliable spectral energy distribution that we separate into 255 proto-stellar and 688 starless sources. Both typologies are found in association with all the distance components observed in the field, up to ~5.8kpc, testifying to the presence of star formation beyond the Perseus arm at these longitudes. Selecting the starless gravitationally bound sources, we identify 590 pre-stellar candidates. Several sources of both proto- and pre-stellar nature are found to exceed the minimum requirement for being compatible with massive star formation based on the mass-radius relation. For the pre-stellar sources belonging to the Local arm (d<~1.5kpc) we study the mass function whose high-mass end shows a power law N(logM){propto}M^-1.0+/-0.2^. Finally, we use a luminosity versus mass diagram to infer the evolutionary status of the sources, finding that most of the proto-stellar sources are in the early accretion phase (with some cases compatible with a Class I stage), while for pre-stellar sources, in general, accretion has not yet started.
- 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}.
- ID:
- ivo://CDS.VizieR/J/MNRAS/464/3796
- Title:
- HI gas mass fraction estimations
- Short Name:
- J/MNRAS/464/3796
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The application of artificial neural networks (ANNs) for the estimation of HI gas mass fraction (M_HI_/M*) is investigated, based on a sample of 13 674 galaxies in the Sloan Digital Sky Survey (SDSS) with HI detections or upper limits from the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA). We show that, for an example set of fixed input parameters (g-r colour and i-band surface brightness), a multidimensional quadratic model yields M_HI_/M* scaling relations with a smaller scatter (0.22dex) than traditional linear fits (0.32dex), demonstrating that non-linear methods can lead to an improved performance over traditional approaches. A more extensive ANN analysis is performed using 15 galaxy parameters that capture variation in stellar mass, internal structure, environment and star formation. Of the 15 parameters investigated, we find that g-r colour, followed by stellar mass surface density, bulge fraction and specific star formation rate have the best connection with M_HI_/M*. By combining two control parameters, that indicate how well a given galaxy in SDSS is represented by the ALFALFA training set (PR) and the scatter in the training procedure ({sigma}_fit_), we develop a strategy for quantifying which SDSS galaxies our ANN can be adequately applied to, and the associated errors in the M_HI_/M* estimation. In contrast to previous works, our M_HI_/M* estimation has no systematic trend with galactic parameters such as M*, g-r and star formation rate. We present a catalogue of M_HI_/M* estimates for more than half a million galaxies in the SDSS, of which ~150000 galaxies have a secure selection parameter with average scatter in the M_HI_/M* estimation of 0.22dex.
- ID:
- ivo://CDS.VizieR/J/ApJS/184/172
- Title:
- High- and intermediate-mass YSOs in the LMC
- Short Name:
- J/ApJS/184/172
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Archival Spitzer Infrared Array Camera (IRAC) and MIPS observations of the Large Magellanic Cloud (LMC) have been used to search for young stellar objects (YSOs). We have carried out independent aperture photometry of these data and merged the results from different passbands to produce a photometric catalog. To verify our methodology we have also analyzed the data from the SAGE and SWIRE Legacy programs; our photometric measurements are in general agreement with the photometry released by these programs. Using our mid-infrared photometric catalogs and two simple selection criteria, [4.5]-[8.0]>2.0 to exclude normal and evolved stars and [8.0]>14-([4.5]-[8.0]) to exclude background galaxies, we have identified a sample of 2910 sources in the LMC that could potentially be YSOs. We then used the Spitzer observations complemented by optical and near-infrared data to carefully assess the nature of each source. From the examination of the initial sample, we suggest that 1172 sources are most likely YSOs. Spitzer IRS observations of 269 of the brightest YSOs from our sample have confirmed that >~95% are indeed YSOs.
- ID:
- ivo://CDS.VizieR/J/A+A/619/A88
- Title:
- High cadence polarization monitoring of OJ287
- Short Name:
- J/A+A/619/A88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a multifrequency, dense radio monitoring program of the blazar OJ287 using the 100-m Effelsberg radio telescope. The program aims to test different binary supermassive black hole (SMBH) scenarios and studying the physical conditions in the central region of this bright blazar. Between December 2015 and January 2017 (MJD 57370-57785), the radio electric vector position angle (EVPA) showed a large clockwise (CW) rotation by about 340{deg} with a mean rate of -1.04{deg}/day. Based on concurrent polarized Very Long Baseline Array (VLBA) data, the rotation seems to originate within the jet core at 43GHz. Optical polarization data show a similar monotonic CW EVPA rotation of about -1.1{deg}/day, superposed by shorter and faster rotations of about 7.8{deg}/day, mainly in the CW sense. When combined, the single dish, VLBI and optical polarization data are consistent with a polarized emission component propagating on a helical trajectory within a bent jet. We constrained the helix arc length (0.26pc) and radius (about 0.04pc) and the projected jet bending arc length (about 1.9-7.6pc). The helical trajectory covers only a part of the jet width, possibly its spine. In addition, we found a stable polarized component with EVPA (-10{deg}) perpendicular to the large scale jet, suggesting dominance of the poloidal magnetic field component.
- ID:
- ivo://CDS.VizieR/J/AJ/154/210
- Title:
- 2015 high-cadence Spitzer microlensing events
- Short Name:
- J/AJ/154/210
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze an ensemble of microlensing events from the 2015 Spitzer microlensing campaign, all of which were densely monitored by ground-based high-cadence survey teams. The simultaneous observations from Spitzer and the ground yield measurements of the microlensing parallax vector {pi}_E_, from which compact constraints on the microlens properties are derived, including ~<25% uncertainties on the lens mass and distance. With the current sample, we demonstrate that the majority of microlenses are indeed in the mass range of M dwarfs. The planet sensitivities of all 41 events in the sample are calculated, from which we provide constraints on the planet distribution function. In particular, assuming a planet distribution function that is uniform in log q, where q is the planet-to-star mass ratio, we find a 95% upper limit on the fraction of stars that host typical microlensing planets of 49%, which is consistent with previous studies. Based on this planet-free sample, we develop the methodology to statistically study the Galactic distribution of planets using microlensing parallax measurements. Under the assumption that the planet distributions are the same in the bulge as in the disk, we predict that ~1/3 of all planet detections from the microlensing campaigns with Spitzer should be in the bulge. This prediction will be tested with a much larger sample, and deviations from it can be used to constrain the abundance of planets in the bulge relative to the disk.
- ID:
- ivo://CDS.VizieR/J/A+A/625/A21
- Title:
- High contrast images of NZ Lup
- Short Name:
- J/A+A/625/A21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Planetary systems hold the imprint of the formation and of the evolution of planets especially at young ages, and in particular at the stage when the gas has dissipated leaving mostly secondary dust grains. The dynamical perturbation of planets in the dust distribution can be revealed with high-contrast imaging in a variety of structures. SPHERE, the high-contrast imaging device installed at the VLT, was designed to search for young giant planets in long period, but is also able to resolve fine details of planetary systems at the scale of astronomical units in the scattered-light regime. As a young and nearby star, NZ Lup was observed in the course of the SPHERE survey. A debris disk had been formerly identified with HST/NICMOS. We observed this system in the near-infrared with the camera in narrow and broad band filters and with the integral field spectrograph. High contrasts are achieved by the mean of pupil tracking combined with angular differential imaging algorithms. The high angular resolution provided by SPHERE allows us to reveal a new feature in the disk which is interpreted as a superimposition of two belts of planetesimals located at stellocentric distances of ~85 and ~115au, and with a mutual inclination of about 5{deg}. Despite the very high inclination of the disk with respect to the line of sight, we conclude that the presence of a gap, that is, a void in the dust distribution between the belts, is likely. We discuss the implication of the existence of two belts and their relative inclination with respect to the presence of planets.
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/470/787
- Title:
- High energy peaked BL Lacs optical spectros.
- Short Name:
- J/A+A/470/787
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The multi-frequency sedentary survey is a flux-limited, statistically well-defined sample of highly X-ray dominated (i.e., with a very high X-ray to radio flux ratio) BL Lacertae objects, which includes 150 sources. In this paper, the third of the series, we report the results of a dedicated optical spectroscopy campaign that, together with results from other independent optical follow-up programs, led to the spectroscopic identification of all sources in the sample. We carried out a systematic spectroscopic campaign for the observation of all unidentified objects of the sample using the ESO 3.6m, the KPNO 4m, and the TNG optical telescopes.