Spectroscopy of spatially extended material around high-redshift radio-loud quasars

Heckman, Timothy M.; Lehnert, M. D.; Miley, G. K.; Breugel, van

doi:10.1086/170660

Cited by 109 publications

(94 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Extended Lyman-α emission has been observed around high-redshift radio galaxies (Heckman et al 1991;van Ojik et al 1996), as well as around radio-quiet quasars (Bunker et al 2003;Christensen et al 2006). For radio-loud quasars or radio-galaxies, the Lyman-α flux of the nebula is an order of magnitude higher (Christensen et al 2006), presumably because the emission of radio-loud quasar gaseous envelopes is enhanced by interactions with the radio jets.…”

Section: The Quasar Nlrmentioning

confidence: 99%

A coronagraphic absorbing cloud reveals the narrow-line region and extended Lyman α emission of QSO J0823+0529

Fathivavsari

Petitjean

Noterdaeme

et al. 2015

Mon. Not. R. Astron. Soc.

View full text Add to dashboard Cite

We report long-slit spectroscopic observations of the quasar SDSS J082303.22+052907.6 (z CIV ∼3.1875), whose Broad Line Region (BLR) is partly eclipsed by a strong damped Lyman-α (DLA; logN (HI)=21.7) cloud. This allows us to study the Narrow Line Region (NLR) of the quasar and the Lyman-α emission from the host galaxy. Using cloudy models that explain the presence of strong NV and PV absorption together with the detection of SiII * and OI * * absorption in the DLA, we show that the density and the distance of the cloud to the quasar are in the ranges 180 < n H < 710 cm −3 and 580 > r 0 >230 pc, respectively. Sizes of the neutral(∼2-9pc) and highly ionized phases (∼3-80pc) are consistent with the partial coverage of the CIV broad line region by the CIV absorption from the DLA (covering factor of ∼0.85). We show that the residuals are consistent with emission from the NLR with CIV/Lyman-α ratios varying from 0 to 0.29 through the profile. Remarkably, we detect extended Lyman-α emission up to 25kpc to the North and West directions and 15kpc to the South and East. We interpret the emission as the superposition of strong emission in the plane of the galaxy up to 10kpc with emission in a wind of projected velocity ∼500km s −1 which is seen up to 25kpc. The low metallicity of the DLA (0.27 solar) argues for at least part of this gas being in-falling towards the AGN and possibly being located where accretion from cold streams ends up.

show abstract

Section: The Quasar Nlrmentioning

confidence: 99%

A coronagraphic absorbing cloud reveals the narrow-line region and extended Lyman α emission of QSO J0823+0529

Fathivavsari

Petitjean

Noterdaeme

et al. 2015

Mon. Not. R. Astron. Soc.

View full text Add to dashboard Cite

show abstract

“…Extended Lyα emission has also been observed around highredshift radio galaxies (Heckman et al 1991a;van Ojik et al 1996), as well as around radio-quiet quasars (Christensen et al 2006;Bunker et al 2003). The Lyα flux from the nebula is about 0.5% of the flux in the integrated broad Lyα line of the QSO, in the case of radio-quiet quasars (RQQs).…”

Section: Introductionmentioning

confidence: 95%

Spectroscopy of extended Lyαenvelopes aroundz = 4.5 quasars

North¹,

Courbin²,

Eigenbrod³

et al. 2012

A&A

View full text Add to dashboard Cite

What are the frequency, shape, kinematics, and luminosity of Lyα envelopes surrounding radio-quiet quasars at high redshift, and is the luminosity of these envelopes related to that of the quasar or not? As a first step towards answering these questions, we have searched for Lyα envelopes around six radio-quiet quasars at z ∼ 4.5, using deep spectra taken with the FORS2 spectrograph attached to the UT1 of the Very Large Telescope (VLT). Using the multi-slit mode allows us to observe several point spread function stars simultaneously with the quasar, and to remove the point-like emission from the quasar, unveiling the faint underlying Lyα envelope with unprecedented depth. An envelope is detected around four of the six quasars, which suggests that these envelopes are very frequent. Their diameter varies in the range 26 < ∼ d < ∼ 64 kpc, their surface brightness in the range 3 × 10 −19 < ∼ μ < ∼ 2 × 10 −17 erg s −1 cm −2 arcsec −2 , and their luminosity in the range 10 42 < ∼ L(Lyα) < ∼ 10 44 erg s −1 . Their shape may be strongly asymmetric. The Lyα emission line full width at half maximum (FWHM) is 900 < FWHM < 2200 km s −1 and its luminosity correlates with that of the broad line region (BLR) of the quasar, with the notable exception of BR2237-0607, the brightest object in our sample. The same holds for the relation between the envelope Lyα luminosity and the ionizing luminosity of the quasar. While the deep slit spectroscopy presented in this paper is very efficient at detecting very faint Lyα envelopes, narrow-band imaging is now needed to measure accurately their spatial extent, radial luminosity profile, and total luminosity. These observables are crucial to help us discriminate between the three possible radiation processes responsible for the envelope emission: (i) cold accretion, (ii) fluorescence induced by the quasar, and (iii) scattering of the BLR photons by cool gas.

show abstract

“…The Heckman et al (1991b) optical spectroscopy of 5 of the H91 QSOs included two of our sample, Q0758+120 and Q0805+046. Using parallel apertures, they extract separate spectra (with a relatively low resolution R ≃ 450) for both AGN and the associated nebulae.…”

Section: Samplementioning

confidence: 99%

“…The blue edge of the nebular emission is near the wavelength of the strong absorption line, but on Figure 8 there is still some nebular flux at the line centre, so the absorber likely has a smaller covering factor for the nebula than for the AGN. Heckman et al (1991b) obtained a spectrum for this nebula and measured a Lyman-α flux 2.5 × 10 −15 ergs cm −2 s −1 , FWHM = 1100 ± 200 and a velocity offset ∆(v) = 200 ± 200 km s −1 . They also detect a weak (7% strength of Lyman-α) narrow CIV emission line, which cannot be verified here as it falls redward of our spectrograph range.…”

Section: Q0805+046mentioning

confidence: 99%

Spectroscopy of 7 radio-loud QSOs at 2 < z < 6: giant Lyman α emission nebulae accreting on to host galaxies

Roche

Humphrey

Binette

2014

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We performed long-slit optical spectroscopy (Gran Telescopio Canarias -Optical System for Imaging and low Resolution Integrated Spectroscopy) of 6 radio-loud QSOs at redshifts 2 < z < 3, known to have giant (∼ 50-100 kpc) Lyman-α emitting nebulae, and detect extended Lyman-α emission for 4, with surface brightness ∼ 10 −16 ergs cm −2 s −1 arcsec −2 and line full width at half-maximum 400-1100 (mean 863) km s −1 . We also observed the z ≃ 5.9 radio-loud QSO, SDSS J2228+0110, and find evidence of a ≥ 10 kpc extended Lyman-α emission nebula, a new discovery for this high-redshift object.Spatially-resolved kinematics of the 5 nebulae are examined by fitting the Lyman-α wavelength at a series of positions along the slit. We found the line-of-sight velocity ∆(v) profiles to be relatively flat. However, 3 of the nebulae appear systematically redshifted by 250-460 km s −1 relative to the Lyman-α 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.

show abstract

Spectroscopy of spatially extended material around high-redshift radio-loud quasars

Cited by 109 publications

References 0 publications

A coronagraphic absorbing cloud reveals the narrow-line region and extended Lyman α emission of QSO J0823+0529

A coronagraphic absorbing cloud reveals the narrow-line region and extended Lyman α emission of QSO J0823+0529

Spectroscopy of extended Lyαenvelopes aroundz = 4.5 quasars

Spectroscopy of 7 radio-loud QSOs at 2 < z < 6: giant Lyman α emission nebulae accreting on to host galaxies

Contact Info

Product

Resources

About