- ID:
- ivo://xaovo/liujun/liujun/q
- Title:
- XAO AGN Flux Monitoring Data
- Short Name:
- liujun_web
- Date:
- 04 Feb 2024 13:22:02
- Publisher:
- Xinjiang Astronomical Observatory,CAS
- Description:
- Active Galactic Nuclei (AGNs) are extragalactic objects characterized by extremely complex physical processes and strong temporal flux variability over almost the whole electromagnetic spectrum, which play a very important role in studying the formation and evolution of galaxies, cosmology and many other astrophysical problems. Flux variability is one of the most remarkable observational characteristics of AGNs and the variability time scales are from minutes to dozens of years. Multi-wavelength flux monitoring is the main means to study the nature of AGN flux variability. In order to systematically study the total flux variability of AGNs in radio band, we launched a long-term program, which is called the quasi- Simultaneous Multiwavelength Monitoring of AGNs with the Nanshan 26-m radio telescope of Xinjiang Astronomical Observatory (XAO), namely SMMAN program. The monitoring data were acquired monthly with the cross-scan mode at C-band (4.8 GHz) and K-band (23.6 GHz) for a sample of about 100 AGNs selected from Fermi-LAT suvery. Additionally, we also conducted weekly monitoring observations or Intra-Day Vairibility (IDV) observations for some of flaring Blazars to reveal their more complex variability time scales.
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- ID:
- ivo://xaovo/__system__/services/registry
- Title:
- XAO Data Center Registry
- Short Name:
- XAO DC Reg
- Date:
- 10 Oct 2018 04:13:56
- Publisher:
- The staff at the XAO Data Center
- Description:
- The publishing registry for the XAO Data Center.
- ID:
- ivo://xaovo/pul/pulsar/q
- Title:
- XAO Pulsar Data Query
- Short Name:
- Pulsar_web
- Date:
- 25 Mar 2024 03:01:22
- Publisher:
- Xinjiang Astronomical Observatory,CAS
- Description:
- The pulsar timing data were obtained with the Nanshan 25M radio telescope. Our observations, which commenced in January 2000, have been made using a dual-channel room-temperature receiver with a bandwidth of 320 MHz centered at 1540 MHz before June 2002. The de-dispersion was provided by a 2X128X2.5 MHz analog filter-bank. A cryogenic receiver was mounted in July 2002, which increases the sensitivity to 0.5 mJy. In January 2010, a digital filter-bank (DFB) system came into operation. The higher time resolution allows us to monitor about 280 pulsars, including ten millisecond-pulsars (MSP). The format of the DFB data is "Psrfit". The "psrchive" program could reads and analyzes the data. Timing observations of 74 pulsars have been regularly carried out between 2002 July to 2009 December. These 74 pulsars have been monitored approximately once every 9d using a dual-channel cryogenic system that receives orthogonal linear polarizations at the central observing frequency of 1540 MHz. The folded profiles obtained are released in format PSRFITS for timing analysis, the file name extension is .FTp. Users can enter "~*.FTp*" in "Product key" filed to search and download it. Non-public data could be used with the permission of Dr. Shengnan Sun (sunshengnan@xao.ac.cn), please send an email for your request.
394. XAO SF Data Query
- ID:
- ivo://xaovo/wugang/wugang/q
- Title:
- XAO SF Data Query
- Short Name:
- wugang_web
- Date:
- 04 Feb 2024 00:50:07
- Publisher:
- Xinjiang Astronomical Observatory,CAS
- Description:
- The molecular spectrum lines data include mainly ammonia and water masers lines at 1.3cm band, as well as formaldehyde and recombination lines at 6cm band observed towards both our Galactic plane and nearby molecular clouds and star-forming regions.
- ID:
- ivo://wfau.roe.ac.uk/xmm_dsa
- Title:
- XMM-Newton Serendipitous Source Catalogue (2XMM)
- Short Name:
- 2XMM
- Date:
- 23 Jan 2024 09:36:54
- Publisher:
- WFAU, Institute for Astronomy, University of Edinburgh
- Description:
- XMM is the second comprehensive catalogue of serendipitous X-ray sources from the European Space Agency's (ESA) XMM-Newton observatory. The 2XMM catalogue is the largest X-ray source catalogue ever produced, containing almost twice as many discrete sources as either the ROSAT survey or pointed catalogues. 2XMM complements deeper Chandra and XMM-Newton small area surveys, probing a much larger sky area.
396. XMM SUSS
- ID:
- ivo://mssl.ucl.ac.uk/xmmsuss_dsa/XMMSUSS
- Title:
- XMM SUSS
- Date:
- 25 Apr 2012 11:27:46
- Publisher:
- XMM at MSSL
- Description:
- The XMM-OM Serendipitous Ultra-violet Source Survey (SUSS) is a catalog of UV sources detected serendipitously by the Optical Monitor (OM) on-board the European Space Agency's (ESA's) XMM-Newton observatory. It has been created at the University College London's (UCL's) Mullard Space Science Laboratory (MSSL) on behalf of ESA and is a partner resource to the 2XMM serendipitous X-ray source catalogue. The catalog contains source detections drawn from 2,417 XMM-OM observations in up to three broad band UV filters made between 2000 February 24 and 2007 March 29. All datasets included were publicly available by 2007 May 01 but note that, due to screening criteria, not all public observations are included in this catalog. Taking account of substantial overlaps between observations, the net sky area covered independently is 29 - 54 square degreees, depending on UV filter. The primary content of the catalog is filter-dependent source positions and magnitudes, and these are accompanied by profile diagnostics and variability statistics. The XMM-OM SUSS catalog contains 753,578 UV source detections above a signal-to-noise threshold limit of 3-sigma which relate to 624,049 unique objects. A significant fraction of sources (12% - UVW2, 11% - UVM2, 11.% - UVW1) are visited more than once during XMM operation, and a large fraction of sources (38% - UVW2, 23% - UVM2, 22% - UVW1) are observed more than once per filter during an individual visit. UVW2, UVM2 and UVW1 refer to the filter bandpasses defined in the Source Properties: Filter Set section of the MSSL documentation for this catalog: <a href="http://www.mssl.ucl.ac.uk/~mds/XMM-OM-SUSS/SourcePropertiesFilters.shtml">http://www.mssl.ucl.ac.uk/~mds/XMM-OM-SUSS/SourcePropertiesFilters.shtml</a>. Consequently, the scope for science based on temporal source variability on timescales of hours to years is broad. The positional accuracy of the catalog detections is typically 1.0 arcsec (1-sigma confidence radius) with a median positional error of 0.67 arcsec. The median AB magnitude of the catalog detections in the three UV bands is 19.56 (UVW2), 20.23 (UVM2) and 20.69 (UVW1). 20% of sources have AB magnitudes fainter than 20.28 (UVW2), 20.97 (UVM2) and 21.54 (UVW1). As part of quality evaluation for the catalog, each field has been tested for astrometric accuracy and visually screened for cosmetic problems, compromising aspect anomalies, stray light, large extended sources and telemetry dropouts. Observations affected by these issues (11.2%) have been removed from the catalog sample. Furthermore, 2% of all observations were selected at random where each source in this sample was tested for falsehood, spuriousness and accuracy of quality flagging. The results of this detailed screening are included in the full documentation. The processing used to generate the catalog is based on the SAS8.0 pipeline developed for the pipeline reduction of all XMM observations. This version includes a number of significant improvements over the previous data processing system (as used by the SSC in routine processing of XMM-Newton data on behalf of ESA). These improvements include a more robust detection scheme for sources close to the limit of sky background, refined quality flagging and a higher success rate (90%) for refined aspect corrections.
- ID:
- ivo://org.gavo.dc/spm4/q/cone
- Title:
- Yale/San Juan SPM4 Catalog
- Short Name:
- SPM4 CS
- Date:
- 23 Mar 2022 13:13:05
- Publisher:
- The GAVO DC team
- Description:
- The SPM4 Catalog contains absolute proper motions, celestial coordinates, and B,V photometry for 103,319,647 stars and galaxies between the south celestial pole and -20 degrees declination. The catalog is roughly complete to V=17.5. It is based on photographic and CCD observations taken with the Yale Southern Observatory's double-astrograph at Cesco Observatory in El Leoncito, Argentina.
- ID:
- ivo://org.gavo.dc/zcosmos/q/ssa
- Title:
- zCosmos Bright Spectroscopic Observations DR2
- Short Name:
- zCosmos SSAP
- Date:
- 23 Mar 2022 13:13:07
- Publisher:
- The GAVO DC team
- Description:
- The zCOSMOS redshift survey used 600h on the VIMOS spectrograph spread over five observing seasons (2005-2009) to obtain spectra of about 20,000 galaxies selected to have Iab < 22.5 across the full 1.7 deg2 of the COSMOS field. This part, "zCOSMOS-bright", was designed to yield a high and fairly uniform sampling rate (about 70%), with a high success rate in measuring redshifts (approaching 100% at 0.5 < z < 0.8), and with sufficient velocity accuracy (about 100 km/s) to efficiently map the environments of galaxies down to the scale of galaxy groups out to redshifts z ~ 1.
- ID:
- ivo://lam.cesam.aspic/zcosmos_20k/q/ssa
- Title:
- zCOSMOS 20k Bright - Simple Spectrum Access
- Short Name:
- zCOSMOS SSAP
- Date:
- 25 Aug 2021 00:22:43
- Publisher:
- The CeSAM VO team
- Description:
- Spectra from the third data release (DR3) of zCOSMOS 20k bright.
