Intra-Day Variability Observations of Two Dozens of Blazars at 4.8 GHz
نویسندگان
چکیده
Two dozens of radio loud active galactic nuclei (AGNs) have been observed with Urumqi 25 m telescope in order to search for intra-day variability (IDV). The target sources are blazars (namely flat spectrum quasars and BL Lac objects) which mostly selected from the observing list RadioAstron AGN monitoring campaigns. observations were carried out at 4.8 GHz two sessions 8-12 February 2014 7-9 March respectively. We report data reduction first results observations. show that majority exhibit IDV 99.9% confidence level, some them quite strong IDV. find blazar 1357 + 769 time. centimeter-wavelength is believed be predominately caused by scintillation emission through local interstellar medium a few hundreds parsecs away Sun. No significant correlation between strength either redshift or Galactic latitude found our sample. timescale along source structure brightness temperature analysis will presented forthcoming paper.
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ژورنال
عنوان ژورنال: Universe
سال: 2021
ISSN: ['2218-1997']
DOI: https://doi.org/10.3390/universe7010015