2006A&A...447..863N


C.D.S. - SIMBAD4 rel 1.7 - 2020.01.27CET04:26:48

2006A&A...447..863N - Astronomy and Astrophysics, volume 447, 863-876 (2006/3-1)

Gas metallicity in the narrow-line regions of high-redshift active galactic nuclei.

NAGAO T., MAIOLINO R. and MARCONI A.

Abstract (from CDS):

We analyze optical (UV rest-frame) spectra of X-ray selected narrow-line QSOs at redshift 1.5≲z≲3.7 found in the Chandra Deep Field South and of narrow-line radio galaxies at redshift 1.2≲z≲3.8 to investigate the gas metallicity of the narrow-line regions and their evolution in this redshift range. Such spectra are also compared with UV spectra of local Seyfert 2 galaxies. The observational data are inconsistent with the predictions of shock models, suggesting that the narrow-line regions are mainly photoionized. The photoionization models with dust grains predict line flux ratios which are also in disagreement with most of the observed values, suggesting that the high-ionization part of the narrow-line regions (which is sampled by the available spectra) is dust-free. The photoionization dust-free models provide two possible scenarios which are consistent with the observed data: low-density gas clouds (nH≲103cm–3) with a sub-solar metallicity (0.2≲Zgas/Z≲1.0), or high-density gas clouds (nH∼105cm–3) with a wide range of gas metallicity (0.2≲Zgas/Z≲5.0). Regardless of the specific interpretation, the observational data do not show any evidence for a significant evolution of the gas metallicity in the narrow-line regions within the redshift range 1.2≲z≲3.8. Instead, we find a trend for more luminous active galactic nuclei to have more metal-rich gas clouds (luminosity-metallicity relation), which is in agreement with the same finding in the studies of the broad-line regions. The lack of evolution for the gas metallicity of the narrow-line regions implies that the major epoch of star formation in the host galaxies of these active galactic nuclei is at z>4.

Abstract Copyright:

Journal keyword(s): galaxies: active - galaxies: evolution - galaxies: nuclei - quasars: emission lines - quasars: general

Simbad objects: 21

goto Full paper

goto View the reference in ADS

Number of rows : 21

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 Mrk 573 Sy2 01 43 57.7763654544 +02 20 59.525472345   14.90 14.07     ~ 471 0
2 M 77 GiP 02 42 40.771 -00 00 47.84 9.70 9.61 8.87 10.1 9.9 ~ 4018 2
3 [LBX2017] 42 Sy2 03 31 51.94 -27 53 27.2 26.57 25.14 25.38 24.74   ~ 54 0
4 [LBX2017] 236 Sy2 03 32 12.9426 -27 52 36.886       24.040 23.899 ~ 42 0
5 [SWM2014] GOODS-S 12741 Sy2 03 32 14.42141 -27 51 10.7305   23.906   24.246 23.38 ~ 45 0
6 [SWM2014] GOODS-S 13628 Sy2 03 32 18.3389 -27 50 55.176   24.89 24.190 23.82 23.039 ~ 69 0
7 [LBX2017] 337 QSO 03 32 18.8321 -27 51 35.476   25.15   24.51 25.128 ~ 64 0
8 NAME Chandra Deep Field-South reg 03 32 28.0 -27 48 30           ~ 1774 1
9 [VV2006] J033229.9-275106 Sy2 03 32 29.8487 -27 51 05.879   27.6 25.05 23.970 24.54 ~ 83 0
10 NAME BzK 4892 AGN 03 32 35.7111 -27 49 16.022   25.681 27.798 25.00 24.645 ~ 63 0
11 2XMM J033237.7-275211 Sy2 03 32 37.76746 -27 52 12.2617   24.651 24.717 24.68 23.885 ~ 68 0
12 [SWM2014] GOODS-S 20788 Sy2 03 32 39.670 -27 48 50.60   27.3148   25.18 24.512 ~ 78 0
13 Mrk 3 Sy2 06 15 36.458 +71 02 15.24 14.21 14.03 12.97     ~ 832 3
14 [STS2002] 52 AGN 08 48 38.0 +44 53 53       24.220   ~ 30 0
15 NGC 4507 Sy2 12 35 36.6328010225 -39 54 33.661858548   12.95 13.54 11.70 12.4 ~ 431 0
16 MCG-03-34-064 Sy2 13 22 24.485 -16 43 42.09   14   13.16   ~ 257 2
17 NGC 5135 Sy2 13 25 44.059 -29 50 01.24   12.58 13.35 11.53 12.2 ~ 417 1
18 NGC 5506 AGN 14 13 14.901 -03 12 27.22   15.25 14.38     ~ 975 0
19 Mrk 1388 Sy1 14 50 37.8519979305 +22 44 03.602995342   15.7       ~ 71 0
20 NGC 7130 AGN 21 48 19.490 -34 57 04.73   12.86 13.87 11.57   ~ 376 0
21 NGC 7674 Sy2 23 27 56.6974755223 +08 46 44.238278540 13.84 13.92 13.23 12.64   ~ 625 4

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2006A&A...447..863N and select 'bookmark this link' or equivalent in the popup menu


2020.01.27-04:26:48

© Université de Strasbourg/CNRS

    • Contact