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.
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.
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.
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.
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.