Spectroscopy of 7 Radio-Loud QSOs at 2<z<6: Giant Lyman-alpha Nebulae
Accreting onto Host Galaxies
N. Roche, A. Humphrey, and L. Binette. (2014)cite arxiv:1407.4046Comment: 16 pages, 15 figures, accepted for publication in MNRAS.
Abstract
We performed long-slit optical spectroscopy (GTC-OSIRIS) of 6 radio-loud QSOs
at redshifts $2<z<3$, known to have giant ($50$-100 kpc) Lyman-$\alpha$
emitting nebulae, and detect extended Lyman-$\alpha$ emission for 4, with
surface brightness $\sim10^-16$ ergs $cm^-2s^-1arcsec^-2$ and line
width FWHM 400-1100 (mean 863) km $s^-1$. We also observed the $z\simeq
5.9$ radio-loud QSO, SDSS J2228+0110, and find evidence of a $10$ kpc
extended Lyman-$\alpha$ emission nebula, a new discovery for this high-redshift
object.
Spatially-resolved kinematics of the 5 nebulae are examined by fitting the
Lyman-$\alpha$ wavelength at a series of positions along the slit. We found the
line-of-sight velocity $\Delta(v)$ profiles to be relatively flat. However, 3
of the nebulae appear systematically redshifted by 250-460 km $s^-1$
relative to the Lyman-$\alpha$ line of the QSO (with no offset for the other
two), which we argue is evidence for infall. One of these (Q0805+046) had a
small ($100$ km $s^-1$) velocity shift across its diameter and a
steep gradient at the centre. Differences in line-of-sight kinematics between
these 5 giant nebulae and similar nebulae associated with high-redshift radio
galaxies (which can show steep velocity gradients) may be due to an orientation
effect, which brings infall/outflow rather than rotation into greater
prominence for the sources observed `on-axis' as QSOs.
Description
[1407.4046] Spectroscopy of 7 Radio-Loud QSOs at 2<z<6: Giant Lyman-alpha Nebulae Accreting onto Host Galaxies
%0 Generic
%1 roche2014spectroscopy
%A Roche, Nathan
%A Humphrey, Andrew
%A Binette, Luc
%D 2014
%K emission nebular qso radio
%T Spectroscopy of 7 Radio-Loud QSOs at 2<z<6: Giant Lyman-alpha Nebulae
Accreting onto Host Galaxies
%U http://arxiv.org/abs/1407.4046
%X We performed long-slit optical spectroscopy (GTC-OSIRIS) of 6 radio-loud QSOs
at redshifts $2<z<3$, known to have giant ($50$-100 kpc) Lyman-$\alpha$
emitting nebulae, and detect extended Lyman-$\alpha$ emission for 4, with
surface brightness $\sim10^-16$ ergs $cm^-2s^-1arcsec^-2$ and line
width FWHM 400-1100 (mean 863) km $s^-1$. We also observed the $z\simeq
5.9$ radio-loud QSO, SDSS J2228+0110, and find evidence of a $10$ kpc
extended Lyman-$\alpha$ emission nebula, a new discovery for this high-redshift
object.
Spatially-resolved kinematics of the 5 nebulae are examined by fitting the
Lyman-$\alpha$ wavelength at a series of positions along the slit. We found the
line-of-sight velocity $\Delta(v)$ profiles to be relatively flat. However, 3
of the nebulae appear systematically redshifted by 250-460 km $s^-1$
relative to the Lyman-$\alpha$ line of the QSO (with no offset for the other
two), which we argue is evidence for infall. One of these (Q0805+046) had a
small ($100$ km $s^-1$) velocity shift across its diameter and a
steep gradient at the centre. Differences in line-of-sight kinematics between
these 5 giant nebulae and similar nebulae associated with high-redshift radio
galaxies (which can show steep velocity gradients) may be due to an orientation
effect, which brings infall/outflow rather than rotation into greater
prominence for the sources observed `on-axis' as QSOs.
@misc{roche2014spectroscopy,
abstract = {We performed long-slit optical spectroscopy (GTC-OSIRIS) of 6 radio-loud QSOs
at redshifts $2<z<3$, known to have giant ($\sim 50$-100 kpc) Lyman-$\alpha$
emitting nebulae, and detect extended Lyman-$\alpha$ emission for 4, with
surface brightness $\sim10^{-16}$ ergs $\rm cm^{-2}s^{-1}arcsec^{-2}$ and line
width FWHM 400-1100 (mean 863) km $\rm s^{-1}$. We also observed the $z\simeq
5.9$ radio-loud QSO, SDSS J2228+0110, and find evidence of a $\geq 10$ kpc
extended Lyman-$\alpha$ emission nebula, a new discovery for this high-redshift
object.
Spatially-resolved kinematics of the 5 nebulae are examined by fitting the
Lyman-$\alpha$ wavelength at a series of positions along the slit. We found the
line-of-sight velocity $\Delta(v)$ profiles to be relatively flat. However, 3
of the nebulae appear systematically redshifted by 250-460 km $\rm s^{-1}$
relative to the Lyman-$\alpha$ line of the QSO (with no offset for the other
two), which we argue is evidence for infall. One of these (Q0805+046) had a
small ($\sim 100$ km $\rm s^{-1}$) velocity shift across its diameter and a
steep gradient at the centre. Differences in line-of-sight kinematics between
these 5 giant nebulae and similar nebulae associated with high-redshift radio
galaxies (which can show steep velocity gradients) may be due to an orientation
effect, which brings infall/outflow rather than rotation into greater
prominence for the sources observed `on-axis' as QSOs.},
added-at = {2014-07-16T09:21:15.000+0200},
author = {Roche, Nathan and Humphrey, Andrew and Binette, Luc},
biburl = {https://www.bibsonomy.org/bibtex/21fafacf4a9037bc5556a33295626bf2a/miki},
description = {[1407.4046] Spectroscopy of 7 Radio-Loud QSOs at 2<z<6: Giant Lyman-alpha Nebulae Accreting onto Host Galaxies},
interhash = {c3437f4a100d77b1e85d3e7c7345fbcd},
intrahash = {1fafacf4a9037bc5556a33295626bf2a},
keywords = {emission nebular qso radio},
note = {cite arxiv:1407.4046Comment: 16 pages, 15 figures, accepted for publication in MNRAS},
timestamp = {2014-07-16T09:21:15.000+0200},
title = {Spectroscopy of 7 Radio-Loud QSOs at 2<z<6: Giant Lyman-alpha Nebulae
Accreting onto Host Galaxies},
url = {http://arxiv.org/abs/1407.4046},
year = 2014
}