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21732. The GAVO VO Puzzlers
- ID:
- ivo://edu.gavo.org/hd/puzzlers
- Title:
- The GAVO VO Puzzlers
- Date:
- 03 Apr 2025 09:45:51
- Publisher:
- The GAVO DC team
- Description:
- The GAVO puzzlers are little training problems solvable by standard VO techniques (data discovery, SIAP, Cone Search, TAP). They assume some familiarity with common astronomical concepts (they were originally given out during meetings of the German Astronomische Gesellschaft) but are designed to be solvable using common, standard tools and in reasonable time. Solutions are also given.
- ID:
- ivo://CDS.VizieR/J/ApJ/892/76
- Title:
- The GBNCC pulsar survey. V. Pulsar census
- Short Name:
- J/ApJ/892/76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Green Bank North Celestial Cap (GBNCC) pulsar survey will cover the entire northern sky ({delta}>-40{deg}) at 350MHz, and is one of the most uniform and sensitive all-sky pulsar surveys to date. We have created a pipeline to reanalyze GBNCC survey data to take a 350MHz census of all pulsars detected by the survey, regardless of their discovery survey. Of the 1413 pulsars in the survey region, we were able to recover 670. For these we present measured signal-to-noise ratios (S/N), flux densities, pulse widths, profiles, and where appropriate, refined measurements of dispersion measures (DMs) (656 out of 670) and new or improved spectral indices (339 out of 670 total, 47 new, 292 improved). We also measure the period-pulse width relation at 350MHz to scale as W{propto}P^-0.27^. Detection scans for several hundred sources were reanalyzed in order to inspect pulsars' single pulse behavior and 223 were found to exhibit evidence of nulling. With a detailed analysis of measured and expected S/N values and the evolving radio frequency interference environment at 350MHz, we assess the GBNCC survey's sensitivity as a function of spin period, DM, and sky position. We find the sky-averaged limiting flux density of the survey to be 0.74mJy. Combining this analysis with PsrPopPy pulsar population simulations, we predict 60/5 nonrecycled/MSP discoveries in the survey's remaining 21000 pointings, and we begin to place constraints on population model parameters.
- ID:
- ivo://CDS.VizieR/J/AJ/149/162
- Title:
- The GBT 67-93.6GHz spectral line survey of Orion-KL
- Short Name:
- J/AJ/149/162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 67-93.6GHz spectral line survey of Orion-KL with the new 4mm Receiver on the Green Bank Telescope (GBT). The survey reaches unprecedented depths and covers the low-frequency end of the 3mm atmospheric window which has been relatively unexplored previously. The entire spectral-line survey is published electronically for general use by the astronomical community. The calibration and performance of the 4mm Receiver on the GBT is also summarized.
21735. The Gemini Observation Log
- ID:
- ivo://CDS.VizieR/B/gemini
- Title:
- The Gemini Observation Log
- Short Name:
- B/gemini
- Date:
- 20 Feb 2022
- Publisher:
- CDS
- Description:
- This database contains a log of the Gemini Telescope observations since 2001, managed by the Canadian Astronomical Data Center (CADC). The data are regularly updated (see the date of the last version at the end of this file). The Gemini Observatory consists of twin 8.1-meter diameter optical/infrared telescopes located on two of the best observing sites on the planet. From their locations on mountains in Hawai'i and Chile, Gemini Observatory's telescopes can collectively access the entire sky. Gemini is operated by a partnership of five countries including the United States, Canada, Brazil, Argentina and Chile. Any astronomer in these countries can apply for time on Gemini, which is allocated in proportion to each partner's financial stake.
- ID:
- ivo://CDS.VizieR/J/A+A/556/A1
- Title:
- The 2.3GHz continuum survey of the GEM project
- Short Name:
- J/A+A/556/A1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Determining the spectral and spatial characteristics of the radio continuum of our Galaxy is an experimentally challenging endeavour for improving our understanding of the astrophysics of the interstellar medium. This knowledge has also become of paramount significance for cosmology, since Galactic emission is the main source of astrophysical contamination in measurements of the Cosmic Microwave Background radiation. In this paper we present the scope of the Galactic Emission Mapping (GEM) project and its results at 2.3GHz. Its observational program was conceived and developed to reveal the large scale properties of Galactic synchrotron radiation in total intensity and polarisation through a self-consistent set of radio continuum surveys between 408MHz and 10GHz. GEM's unique observational strategy and experimental design aim at the production of foreground templates in order to address the mutual inconsistencies between existing surveys.
21737. The GLEAM 4-Jy (G4Jy) Sample
- ID:
- ivo://CDS.VizieR/VIII/105
- Title:
- The GLEAM 4-Jy (G4Jy) Sample
- Short Name:
- VIII/105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Murchison Widefield Array (MWA) has observed the entire southern sky (Declination, {delta}<30{deg}) at low radio-frequencies, over the range 72-231MHz. These observations constitute the GaLactic and Extragalactic All-sky MWA (GLEAM) Survey, and we use the extragalactic catalogue (Galactic latitude, |b|>10{deg}) to define the GLEAM 4-Jy (G4Jy) Sample. This is a complete sample of the 'brightest' radio-sources (S_151MHz_>4Jy), the majority of which are active galactic nuclei with powerful radio-jets. Crucially, low-frequency observations allow the selection of such sources in an orientation-independent way (i.e. minimising the bias caused by Doppler boosting, inherent in high-frequency surveys). We then use higher-resolution radio images, and information at other wavelengths, to morphologically classify the brightest components in GLEAM. We also conduct cross-checks against the literature, and perform internal matching, in order to improve sample completeness (which is estimated to be >95.5%). This results in a catalogue of 1,863 sources, making the G4Jy Sample over 10 times larger than that of the revised Third Cambridge Catalogue of Radio Sources (3CRR; S_178MHz_>10.9Jy). Of these G4Jy sources, 78 are resolved by the MWA (Phase-I) synthesised beam (~2' at 200MHz), and we label 67% of the sample as 'single', 26% as 'double', 4% as 'triple', and 3% as having 'complex' morphology at ~1GHz (45" resolution). We characterise the spectral behaviour of these objects in the radio, and find that the median spectral-index is {alpha}=-0.740+/-0.012 between 151MHz and 843MHz, and {alpha}=-0.786+/-0.006 between 151MHz and 1400MHz (assuming a power-law description, S_{nu}_{prop.to}{nu}^{alpha}^), compared to {alpha}=-0.829+/-0.006 within the GLEAM band. Alongside this, our value-added catalogue provides mid-infrared source associations (subject to 6" resolution at 3.4um) for the radio emission, as identified through visual inspection and thorough checks against the literature. As such, the G4Jy Sample can be used as a reliable training set for cross-identification via machine-learning algorithms. We also estimate the angular size of the sources, based on their associated components at ~1GHz, and perform a flux-density comparison for 67 G4Jy sources that overlap with 3CRR. Analysis of multi-wavelength data, and spectral curvature between 72MHz and 20GHz, will be presented in subsequent papers, and details for accessing all G4Jy overlays are provided at https://github.com/svw26/G4Jy.
21738. The Global TAP Schema GloTS
- ID:
- ivo://org.gavo.dc/std/glots
- Title:
- The Global TAP Schema GloTS
- Date:
- 20 Apr 2023 00:19:19
- Publisher:
- The GAVO DC team
- Description:
- The Global TAP schema is an attempt at a simple way to present a union of all TAP_SCHEMA instances globally, where right now GloTS only contains tables and columns. It is primarily intended as a quick (and relatively dirty) way for data collection discovery until other means are ready.
- ID:
- ivo://CDS.VizieR/J/AJ/155/116
- Title:
- The globular cluster M14.II. Variable stars
- Short Name:
- J/AJ/155/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present time-series BVI photometry for the Galactic globular cluster NGC 6402 (M14). The data consist of ~137 images per filter, obtained using the 0.9 and 1.0 m SMARTS telescopes at the Cerro Tololo Inter-American Observatory. The images were obtained during two observing runs in 2006-2007. The image-subtraction package ISIS, along with DAOPHOT II/ALLFRAME, was used to perform crowded-field photometry and search for variable stars. We identified 130 variables, eight of which are new discoveries. The variable star population is comprised of 56 ab-type RR Lyrae stars, 54 c-type RR Lyrae, 6 type II Cepheids, 1 W UMa star, 1 detached eclipsing binary, and 12 long-period variables. We provide Fourier decomposition parameters for the RR Lyrae, and discuss the physical parameters and photometric metallicity derived therefrom. The M14 distance modulus is also discussed, based on different approaches for the calibration of the absolute magnitudes of RR Lyrae stars. The possible presence of second-overtone RR Lyrae in M14 is critically addressed, with our results arguing against this possibility. By considering all of the RR Lyrae stars as members of the cluster, we derive <P_ab_>=0.589 days. This, together with the position of the RR Lyrae stars of both Bailey types in the period-amplitude diagram, suggests an Oosterhoff-intermediate classification for the cluster. Such an intermediate Oosterhoff type is much more commonly found in nearby extragalactic systems, and we critically discuss several other possible indications that may point to an extragalactic origin for this cluster.
- ID:
- ivo://CDS.VizieR/J/A+AS/125/1
- Title:
- The globular cluster NGC 1904
- Short Name:
- J/A+AS/125/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 2 contains CCD UBV photometry of 2451 stars in the globular cluster NGC 1904. In the printed version, only the first 30 lines of the table were presented for guidance.
