کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1772041 1020916 2009 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A VLBI Study of Compact Steep Spectrum Sources 3C43, 3C48 and 3C454
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم نجوم و فیزیک نجومی
پیش نمایش صفحه اول مقاله
A VLBI Study of Compact Steep Spectrum Sources 3C43, 3C48 and 3C454
چکیده انگلیسی

We used the VLBA(NRAO, USA) and made VLBI observations towards the compact steep spectrum sources 3C43, 3C48 and 3C454 at the central frequency 1.6 GHz, and obtained their total flux density maps and information on the structures of their components. By comparison with the previous data, we analyzed the variations of their flux densities as well as the displacements of their components. It is found that the total flux density of the source 3C43, as well as the flux densities and relative positions of its components are quite stable in 14 years. For the source 3C454, the total flux density and the flux densities of its components are also relatively stable, but two of the components moved away from the central core with superluminal velocities of 21.6c and 17.7c. Fitted to their flux densities at 4 L-band frequencies, the spectral indexes of the sources 3C43 and 3C454 were obtained to be 0.63 and 0.86, respectively, in good agreement with previous results, and consistent with the definition of α ≥0.5 for compact steep spectrum sources.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chinese Astronomy and Astrophysics - Volume 33, Issue 2, April–June 2009, Pages 133-138