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- ID:
- ivo://aip.gavo.org/rr/q/create
- Title:
- GAVO RegTAP Service (Potsdam mirror)
- Short Name:
- RegTAP Potsdam
- Date:
- 26 Mar 2024 14:07:04
- Publisher:
- GAVO at Leibniz-Institute for Astrophysics Potsdam
- Description:
- Tables containing the information in the IVOA Registry. To query these tables, use `our TAP service`_. For more information and example queries, see the `RegTAP specification`_. .. _our TAP service: /__system__/tap/run/info .. _RegTAP specification: http://www.ivoa.net/documents/RegTAP/
- ID:
- ivo://CDS.VizieR/VIII/40
- Title:
- GB6 catalog of radio sources
- Short Name:
- VIII/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Green Bank 4.85GHz (lambda~6cm) survey was made with the NRAO seven-beam receiver on the (former) 91m telescope during 1986 November and 1987 October. The final set of sky maps covering the declination band 0deg<Dec.<+75deg was constructed with data from both epochs. Its noise and position errors are nearly a factor of 2^(1/2)^ smaller than in the epoch 1987 maps, from which the 87GB catalog <VIII/14> of 54,579 sources stronger than S~25mJy was extracted. Therefore, we used the new maps to make the GB6 catalog of 75,162 discrete sources with angular sizes phi<=10.5arcmin and flux densities S>=18mJy. This catalog is available in machine-readable versions with either B1950 or J2000 positions and as a printed book with B1950 positions. The GB6 weighted differential source counts S^(5/2)n(S) between 18 mJy and 7Jy agree well with evolutionary models based on independent data.
- ID:
- ivo://CDS.VizieR/VIII/14
- Title:
- 87GB Catalog of radio sources
- Short Name:
- VIII/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- of paper: The 91m telescope in Green Blank was used during 1987 October to map 6.0sr of the sky in the [0,+75]degrees declination band at 4.85GHz. We present the 87GB catalog of 54579 discrete sources with angular sizes less than about 10.5arcmin and stronger than S about 25mJy derived from these maps. The catalog positions and flux densities have been corrected for known map biases. Their estimated rms uncertainties were verified by comparison with more accurate positions and flux densities available for some sources. The 4.85GHz normalized source counts S^5/2^.n(S) between 25mJy and 10Jy were obtained and agree well with evolutionary models based on independent data.
- ID:
- ivo://CDS.VizieR/J/A+A/525/A53
- Title:
- GBM parameters for detected FERMI bursts
- Short Name:
- J/A+A/525/A53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the constraints imposed on the luminosity function (LF) of long duration gamma ray bursts (LGRBs) by the flux distribution of bursts detected by the GBM at ~1MeV, and the implications of the non detection of the vast majority, ~95%, of the LGRBs at higher energy, ~1GeV, by the LAT detector.
- ID:
- ivo://CDS.VizieR/J/MNRAS/443/1044
- Title:
- GBT HI observations of 1194 spirals
- Short Name:
- J/MNRAS/443/1044
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present HI 21cm observations of 1194 galaxies out to a redshift of 10000km/s selected as inclined spirals (i>~60{deg}) from the 2MASS redshift survey. These observations were carried out at the National Radio Astronomy Observatory Robert C. Byrd Green Bank Telescope (GBT). This observing programme is part of the 2MASS Tully-Fisher (2MTF) survey. This project will combine Hi widths from these GBT observations with those from further dedicated observing at the Parkes Telescope, from the Arecibo Legacy Fast Arecibo L-band Feed Array survey at Arecibo, and S/N>10 and spectral resolution v_res_<10km/s published widths from a variety of telescopes. We will use these Hi widths along with 2MASS photometry to estimate Tully-Fisher distances to nearby spirals and investigate the peculiar velocity field of the local Universe. In this paper, we report on detections of neutral hydrogen in emission in 727 galaxies, and measure good signal to noise and symmetric HI global profiles suitable for use in the Tully-Fisher relation in 484.
- ID:
- ivo://CDS.VizieR/J/ApJ/902/39
- Title:
- GBT HI obs. of ultradiffuse galaxies
- Short Name:
- J/ApJ/902/39
- Date:
- 10 Mar 2022 13:55:53
- Publisher:
- CDS
- Description:
- We present neutral hydrogen (HI) observations using the Robert C. Byrd Green Bank Telescope (GBT) of 70 optically detected UDG candidates in the Coma region from the Systematically Measuring Ultra-Diffuse Galaxies survey (SMUDGes). We detect HI in 18 targets, confirming nine to be gas-rich UDGs and the remainder to be foreground dwarfs. None of our HI-detected UDGs are Coma Cluster members and all but one are in low-density environments. The HI-detected UDGs are bluer and have more irregular morphologies than the redder, smoother candidates not detected in HI, with the combination of optical color and morphology being a better predictor of gas richness than either parameter alone. There is little visual difference between the gas-rich UDGs and the foreground dwarfs in the SMUDGes imaging, and distances are needed to distinguish between them. We find that the gas richnesses of our HI-confirmed UDGs and those from other samples scale with their effective radii in two stellar mass bins, possibly providing clues to their formation. We attempt to place our UDGs on the baryonic Tully-Fisher relation (BTFR) using optical ellipticities and turbulence-corrected HI line widths to estimate rotation velocities, but the potential systematics associated with fitting smooth Sersic profiles to clumpy, low-inclination disks of low surface brightness precludes a meaningful analysis of potential BTFR offsets. These observations are a pilot for a large campaign now under way at the GBT to use the HI properties of gas-rich UDGs to quantitatively constrain how these galaxies form and evolve.
- ID:
- ivo://CDS.VizieR/J/ApJ/763/80
- Title:
- GBT 350MHz survey. I. 13 new pulsars
- Short Name:
- J/ApJ/763/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Over the summer of 2007, we obtained 1191hr of "drift-scan" pulsar search observations with the Green Bank Telescope at a radio frequency of 350MHz. Here we describe the survey setup, search procedure, and the discovery and follow-up timing of 13 pulsars. Among the new discoveries, one (PSR J1623-0841) was discovered only through its single pulses, two (PSRs J1327-0755 and J1737-0814) are millisecond pulsars, and another (PSR J2222-0137) is a mildly recycled pulsar. PSR J1327-0755 is a 2.7ms pulsar at a dispersion measure (DM) of 27.9pc/cm3 in an 8.7 day orbit with a minimum companion mass of 0.22M_{sun}_. PSR J1737-0814 is a 4.2ms pulsar at a DM of 55.3pc/cm3 in a 79.3 day orbit with a minimum companion mass of 0.06M_{sun}_. PSR J2222-0137 is a 32.8ms pulsar at a very low DM of 3.27pc/cm3 in a 2.4 day orbit with a minimum companion mass of 1.11M_{sun}_. It is most likely a white-dwarf-neutron-star system or an unusual low-eccentricity double neutron star system. Ten other pulsars discovered in this survey are reported in the companion paper Lynch et al. (2013ApJ...763...81L).
- ID:
- ivo://CDS.VizieR/J/ApJS/177/255
- Title:
- GBT multiwavelength survey of Galactic center
- Short Name:
- J/ApJS/177/255
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the results of a radio continuum survey of the central 4{deg}x1{deg} with the 100m Green Bank Telescope (GBT) at wavelengths of 3.5, 6, 20, and 90cm. The 3.5 and 6cm surveys are the most sensitive and highest resolution single-dish surveys made of the central degrees of our Galaxy. We present catalogs of compact and extended sources in the central 4{deg} of our Galaxy, including detailed spectral index studies of all sources. The analysis covers star-forming regions such as Sgr B and Sgr C, where we find evidence of a mixture of thermal and nonthermal emission. The analysis quantifies the relative contribution of thermal and nonthermal processes to the radio continuum flux density toward the Galactic center (GC) region. In the central 4{deg}x1{deg} of the GC, the thermal and nonthermal flux fractions for all compact and diffuse sources are 28%/72% at 3.5cm and 19%/81% at 6cm. The total flux densities from these sources are 783+/-52 and 1063+/-93Jy at 3.5 and 6cm, respectively, excluding the contribution of Galactic synchrotron emission.
- ID:
- ivo://CDS.VizieR/J/A+A/627/A34
- Title:
- GC hot UV-bright stars model spectra
- Short Name:
- J/A+A/627/A34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed a census of the UV-bright population in 78 globular clusters using wide-field UV telescopes. This population includes a variety of phases of post-horizontal branch (HB) evolution, including hot post-asymptotic giant branch (AGB) stars, and post-early AGB stars. There are indications that old stellar systems like globular clusters produce fewer post-(early) AGB stars than currently predicted by evolutionary models, but observations are still scarce. We wish to derive effective temperatures, surface gravities, and helium abundances of the luminous hot UV-bright stars in these clusters to determine their evolutionary status and compare the observed numbers to predictions from evolutionary theory. We obtained FORS2 spectroscopy of 11 of these UV-selected objects (covering a range of -2.3<[Fe/H]<-1.0), which we (re-)analysed together with previously observed data. We used model atmospheres of different metallicities, including super-solar ones. Where possible, we verified our atmospheric parameters using UV spectrophotometry and searched for metal lines in the optical spectra. We calculated evolutionary sequences for four metallicity regimes and used them together with information about the HB morphology of the globular clusters to estimate the expected numbers of post-AGB stars. We find that metal-rich model spectra are required to analyse stars hotter than 40000 K. Seven of the eleven new luminous UV-bright stars are post-AGB or post-early AGB stars, two are evolving away from the HB, one is a foreground white dwarf, and another is a white dwarf merger. Taking into account published information on other hot UV-bright stars in globular clusters, we find that the number of observed hot post-AGB stars generally agrees with the predicted values, although the numbers are still low. Spectroscopy is clearly required to identify the evolutionary status of hot UV-bright stars. For hotter stars, metal-rich model spectra are required to reproduce their optical and UV spectra, which may affect the flux contribution of hot post-AGB stars to the UV spectra of evolved populations. Adding published information on other hot UV-bright stars in globular clusters, we find that the number of observed hot post-AGB stars generally agrees with the predicted values, although the numbers are still low.