• Zhen Ding

      Articles written in Journal of Astrophysics and Astronomy

    • Radio Observation of the 11-Month Fermi-AGN at Urumqi Observatory

      Zhen Ding Xiang Liu Jun Liu Lang Cui H. G. Song

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      We carry out flux observation at 5 GHz for 124 sources from the ‘clean’ sample of Fermi catalog 1LAC (The First LAT AGN Catalog) with Urumqi 25 m telescope. We find that it is obvious that there is a correlation between the 𝛾-ray and the radio flux density for blazars. For the subclasses, the correlation for FSRQs is strong, but the correlation for BL Lacs is weak.

    • Variability Study of the S5 Sample

      Jun Liu Lang Cui Xiang Liu Zhen Ding Hua-Gang Song

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      We present the results of flux density monitoring of the S5 sample at 5GHz with the Urumqi 25-m radio telescope during Dec. 2008 and Nov. 2009. Most sources exhibited > 2% rms variation in our one-year monitoring. Twenty-five highly variable sources were detected at a confidence level of 99%. Weaker sources show larger amplitude of variability. Sources that have a steep spectral index are not as variable in flux density as the flat spectrum objects. No galactic dependent variability was found. Supplemental IDV observations for several strong variables were performed in order to search for possible rapid variability, and to compare variability on different time-scales. The absence of short time-scale variability in S5 0633+73 indicates that mid time-scale variability is a main source of intrinsic origin.

  • Journal of Astrophysics and Astronomy | News

    • Continuous Article Publication

      Posted on January 27, 2016

      Since January 2016, the Journal of Astrophysics and Astronomy has moved to Continuous Article Publishing (CAP) mode. This means that each accepted article is being published immediately online with DOI and article citation ID with starting page number 1. Articles are also visible in Web of Science immediately. All these have helped shorten the publication time and have improved the visibility of the articles.

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