3 research outputs found
Lyman- emission from a WISE-selected optically faint powerful radio galaxy M151304.72-252439.7 at = 3.132
We report the detection of a large ( kpc) and luminous
nebula [ = ] around an optically faint (r mag) radio
galaxy M1513-2524 at =3.132. The double-lobed radio emission
has an extent of 184 kpc, but the radio core, i.e., emission associated with
the active galactic nucleus (AGN) itself, is barely detected. This object was
found as part of our survey to identify high- quasars based on Wide-field
Infrared Survey Explorer (WISE) colors. The optical spectrum has revealed
, NV, CIV and HeII emission lines with a very weak
continuum. Based on long-slit spectroscopy and narrow band imaging centered on
the emission, we identify two spatial components: a
"compact component" with high velocity dispersion () seen in all three lines, and an "extended component",
having low velocity dispersion (i.e., 700-1000). The
emission line ratios are consistent with the compact component being in
photoionization equilibrium with an AGN. We also detect spatially extended
associated absorption, which is blue-shifted within
250-400 of the peak. The probability of
absorption detection in such large radio sources is found
to be low (10%) in the literature. M1513-2524 belongs to the top few
percent of the population in terms of and radio
luminosities. Deep integral field spectroscopy is essential for probing this
interesting source and its surroundings in more detail.Comment: 19 pages, 15 figures, Accepted for publication in MNRA
Spatially resolved Lyman-α emission around radio bright quasars
International audienceWe use Southern African Large Telescope (SALT) to perform long-slit spectroscopic observations of 23 newly discovered radio-loud quasars (RLQs) at 2.7 1000 km/s in all, except one). Using the samples of high-z radio-loud quasars and galaxies from literature, we confirm the correlation between the Lyα halo luminosity and its size with L 420MHz. The same quantities are found to be correlating weakly with the projected linear size of the radio emission. Our sample is the second largest sample of RLQs being studied for the presence of diffuse Lyα emission and fills in a redshift gap between previous such studies. Integral Field Spectroscopy is required to fully understand the relationship between the large scale radio emission and the overall distribution, kinematics and over density of Lyα emission in the field of these RLQs