Chandra detection of a parsec scale wind in the Broad Line Radio Galaxy 3C 382

TL;DR

This paper reports the first detection of a parsec-scale wind in a radio-loud AGN, 3C 382, using Chandra X-ray spectroscopy to identify high-ionization outflows at several parsecs from the nucleus.

Contribution

It provides the first evidence of a parsec-scale wind in a radio-loud AGN, expanding understanding of AGN outflows beyond radio-quiet sources.

Findings

Detected high-ionization absorption lines in X-ray spectrum

Measured outflow velocity of -840 km/s

Estimated outflow origin within 10-1000 parsecs

Abstract

We present unambiguous evidence for a parsec scale wind in the Broad-Line Radio Galaxy (BLRG) 3C 382, the first radio-loud AGN, with $R_{\rm L} = \log_{10}(f_{\rm 5GHz}/f_{4400})>1$, whereby an outflow has been measured with X-ray grating spectroscopy. A 118 ks Chandra grating (HETG) observation of 3C 382 has revealed the presence of several high ionization absorption lines in the soft X-ray band, from Fe, Ne, Mg and Si. The absorption lines are blue-shifted with respect to the systemic velocity of 3C 382 by -840\pm60 km/s and are resolved by Chandra with a velocity width of 340\pm70 km/s. The outflow appears to originate from a single zone of gas of column density $N_{\rm H} = 1.3 \times 10^{21}$ cm$^{-2}$ and ionization parameter $\log \xi = 2.45$. From the above measurements we calculate that the outflow is observed on parsec scales, within the likely range from 10-1000 pc, i.e., consistent with an origin in the Narrow Line Region.