We observed 1938-155, a broad line radio galaxy (BLRG), with the Very Large Array (VLA) at 90cm with an angular resolution of 6.8' × 4.0'. The source consists of two components separated by 4 arcsec (- 20...We observed 1938-155, a broad line radio galaxy (BLRG), with the Very Large Array (VLA) at 90cm with an angular resolution of 6.8' × 4.0'. The source consists of two components separated by 4 arcsec (- 20kpc, for H0 = 65km s-1 Mpc-1, q0 = 0.5) along the SE-NW direction. Both components show steep-spectra with a similar spectral index α - 0.83 ± 0.07 (Sv ∝ v-α). The bright double components are surrounded by a low-brightness cocoon. The radio properties of the two bright components are consistent with the hot spots produced by twin jets. An upper limit of - 0.0008 for the core dominance parameter (R) is inferred, suggesting there is no prominent radio core in the source. Assuming a modest viewing angle 30f77, a jet velocity is estimated - 0.07 c, based on the jet to counter-jet brightness ratio (J). The lower limit in jet speed inferred is consistent with no Doppler beaming effect on the jet. The radio galaxy 1938-155 could be an exceptional BLRG with no prominent radio core or jet.展开更多
The gamma-ray blazar 1611+343 was observed with polarization VLBI mode at 5 GHz in February 1999. The total intensity (I) VLBI image of the source shows a core-jet structure. The jet bends eastward at - 3 mas south of...The gamma-ray blazar 1611+343 was observed with polarization VLBI mode at 5 GHz in February 1999. The total intensity (I) VLBI image of the source shows a core-jet structure. The jet bends eastward at - 3 mas south of the core. Four components have been detected from results of fitting, with apparent speeds estimated at 6.7 ±0.7, 2.5 ±0.3, 4.5 ±0.5 h-1c for three jet components (taking H0 = 100 h km s-1 Mpc-1, q0 = 0.5). The polarization (P) VLBI image of 1611+343 displays the polarized configuration in the jet. The mechanism of the curved jet is discussed.展开更多
基金the National Natural Science Foundation of China.
文摘We observed 1938-155, a broad line radio galaxy (BLRG), with the Very Large Array (VLA) at 90cm with an angular resolution of 6.8' × 4.0'. The source consists of two components separated by 4 arcsec (- 20kpc, for H0 = 65km s-1 Mpc-1, q0 = 0.5) along the SE-NW direction. Both components show steep-spectra with a similar spectral index α - 0.83 ± 0.07 (Sv ∝ v-α). The bright double components are surrounded by a low-brightness cocoon. The radio properties of the two bright components are consistent with the hot spots produced by twin jets. An upper limit of - 0.0008 for the core dominance parameter (R) is inferred, suggesting there is no prominent radio core in the source. Assuming a modest viewing angle 30f77, a jet velocity is estimated - 0.07 c, based on the jet to counter-jet brightness ratio (J). The lower limit in jet speed inferred is consistent with no Doppler beaming effect on the jet. The radio galaxy 1938-155 could be an exceptional BLRG with no prominent radio core or jet.
基金the National Natural Science Foundation of China(19973103)the National Climbing Program.The authors are grateful to the staf of the EVN for the support of the observing projects
文摘The gamma-ray blazar 1611+343 was observed with polarization VLBI mode at 5 GHz in February 1999. The total intensity (I) VLBI image of the source shows a core-jet structure. The jet bends eastward at - 3 mas south of the core. Four components have been detected from results of fitting, with apparent speeds estimated at 6.7 ±0.7, 2.5 ±0.3, 4.5 ±0.5 h-1c for three jet components (taking H0 = 100 h km s-1 Mpc-1, q0 = 0.5). The polarization (P) VLBI image of 1611+343 displays the polarized configuration in the jet. The mechanism of the curved jet is discussed.
