What is the difference between radio-loud and radio-quiet quasi-stellar objects?

Hutchings, J. B.; Janson, Thomas; Neff, Susan G.

doi:10.1086/167626

Cited by 43 publications

(63 citation statements)

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“…The closest pair (''a'') at $12 00 to the east consists of two large elliptical galaxies (one galaxy at 10 00 [P:A: ' 153 ] and one galaxy at 15 00 [P:A: ' 161 ] to the southeast). Hutchings et al (1989) speculated that the QSO may be interacting with these. The northern galaxy of this pair shows a shell-like structure.…”

Section: A3 Pg 0923+201mentioning

confidence: 99%

Evidence for Merger Remnants in Early‐Type Host Galaxies of Low‐Redshift QSOs1

Bennert

Canalizo

Jungwiert

et al. 2008

ApJ

167

206

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We present results from a pilot HST ACS deep imaging study in broadband Vof five low-redshift QSO host galaxies classified in the literature as ellipticals. The aim of our study is to determine whether these early-type hosts formed at high redshift and have since evolved passively, or whether they have undergone relatively recent mergers that may be related to the triggering of the nuclear activity. We perform two-dimensional modeling of the light distributions to analyze the host galaxies' morphology. We find that, while each host galaxy is reasonably well fitted by a de Vaucouleurs profile, the majority of them (4/5) reveal significant fine structure such as shells and tidal tails. These structures contribute between $5% and 10% to the total V-band luminosity of each host galaxy within a region of r $ 3r eA and are indicative of merger events that occurred between a few hundred Myr and a Gyr ago. These timescales are comparable to starburst ages in the QSO hosts previously inferred from Keck spectroscopy. Our results thus support a consistent scenario in which most of the QSO host galaxies suffered mergers with accompanying starbursts that likely also triggered the QSO activity in some way, but we are also left with considerable uncertainty on physical mechanisms that might have delayed this triggering for several hundred Myr after the merger.

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Section: A3 Pg 0923+201mentioning

confidence: 99%

Evidence for Merger Remnants in Early‐Type Host Galaxies of Low‐Redshift QSOs1

Bennert

Canalizo

Jungwiert

et al. 2008

ApJ

167

206

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“…The FR IÏs and IIÏs shown are from the 2 Jy sample (Wall & Peacock 1985), with morphological classiÐcations from Morganti et al (1993). The quasar data are from Taylor et al (1996), Bahcall et al (1997), Boyce et al (1998), andHutchings et al (1989). The lines dividing FR I and FR II sources are from the models of Bicknell (1995 ; avoid luminosity-redshift biases.…”

Section: Comparison To Radio Galaxiesmentioning

confidence: 99%

“…1999). Several studies have reported that the host galaxies of radio-quiet AGNs are systematically less luminous than those of radio-loud AGNs (Smith & Heckman 1986 ;Hutchings et al 1989 ;& Ve ron-Cetty Woltjer 1990 ;Lowenthal et al 1995), although this e †ect was not found in other samples matched for redshift and luminosity (Taylor et al 1996 ;Hooper et al 1997). It has also been suggested that radio-quiet AGNs have less disturbed morphologies (Hutchings et al 1989), and certainly dust, tidal tails, and/or close companion galaxies are prevalent in radio-loud AGNs (Smith & Heckman 1986 ;Yee & Green 1987 ;Bahcall et al 1997 ;Canalizo & Stockton 1997 ;Martel et al 1997 ;Pentericci et al 1999).…”

Section: Introductionmentioning

confidence: 99%

TheHubble Space TelescopeSurvey of BL Lacertae Objects. II. Host Galaxies

Urry

Scarpa

O’Dowd

et al. 2000

ApJ

255

352

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We have used the Hubble Space T elescope (HST ) WFPC2 camera to survey 132 BL Lac objects comprising seven complete radio-, X-rayÈ, and optically selected samples. We obtained useful images for 110 targets spanning the redshift range These represent an unbiased subsample of the original 0 [ z [ 1.3. 132 since they were snapshots selected to Ðll random holes in the HST schedule. The exposure times ranged from a few hundred to D1000 s, increasing with redshift. Most images were taken in the F702W Ðlter ; those already observed in F814W during Cycle 5 were reobserved in F606W to give broader wavelength coverage. The data were analyzed uniformly, and both statistical and systematic errors were estimated (the latter dominate). In of the BL Lac images, host galaxies are detected, including nearly all 2 3 for z \ 0.5 (58 of 63). In contrast, only one-quarter of the BL Lac objects with z [ 0.5 (six of 22) were resolved because of the relatively short exposure times, and these tend to be very luminous host galaxies. The highest redshift host galaxy detected is in a BL Lac object at z \ 0.664. HST data add critical morphological information in the range a few tenths to a few arcseconds. In 58 of the 72 resolved host galaxies, a de Vaucouleurs proÐle is signiÐcantly preferred, at conÐdence, over a pure exponential Z99% disk ; the two Ðts are comparable in the remaining 14 cases because of their generally lower signal-tonoise ratios. These results limit the number of disk systems to at most 8% of BL Lac objects (at 99% conÐdence) and are consistent with all BL Lac host galaxies being ellipticals. The detected host galaxies are luminous ellipticals with a median absolute K-corrected magnitude of mag (rms M R D [23.7^0.6 dispersion), at least 1 mag brighter than M* and comparable to brightest cluster galaxies. The galaxy morphologies are generally smooth and undisturbed, with small or negligible ellipticities The (v [ 0.2). half-light surface brightness is anticorrelated with half-light radius in quantitatively the same way as other elliptical galaxies, indicating that apart from their highly active nuclei, BL Lac objects appear to be absolutely normal ellipticals. There is no correlation between host galaxy and observed nuclear magnitude or estimated jet power corrected for beaming. If black hole mass is correlated linearly with bulge mass in general, this implies a large range in Eddington ratio. The host galaxies of the radio-selected and X-rayÈselected BL Lac objects are comparable in both morphology and luminosity, strongly suggesting that nuclear properties do not have a dramatic e †ect on large-scale host galaxy properties, or vice versa. BL Lac objects have extended radio powers and host galaxy magnitudes very much like those of FR I galaxies, and quite distinct from FR IIÏs, which instead are more similar to quasars. Thus the present data strongly support the uniÐcation picture with FR I galaxies constituting the bulk of the parent population of BL Lac objects.

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“…Extended nebulosities around quasars were investigated by several groups using various facilities from the ground (e.g., Hutchings, Janson, & Neff 1989;Veron-Cetty & Woltjer 1990;McLeod & Rieke 1995;Taylor et al 1996;Kotilainen & Falomo 2000). Altogether, these works have confirmed the presence of the host galaxies.…”

Section: Introductionmentioning

confidence: 96%

Host Galaxies of Low‐zRadio‐loud Quasars: A Search ofHubble Space TelescopeArchives

Pagani¹,

Falomo²,

Treves³

2003

ApJ

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We searched the Hubble Space Telescope (HST) archives for unpublished Wide Field Planetary Camera 2 images of low-redshift (z < 0:5) radio-loud quasars (RLQs). This led to the identification of 11 objects. Here we present the results of the analysis of these images from which we derive the properties of their host galaxies. All objects are clearly resolved, and their surrounding nebulosity is consistent with an elliptical galaxy model. These new data, together with previous published HST observations, form a sample of 34 sources that significantly expand all previous studies of low-redshift RLQs based on HST data. For this full sample we derive the average absolute magnitude of the host galaxies M R h i ¼ À24:01 AE 0:48 and the effective radius R e h i ¼ 10:5 AE 3:7 kpc. No significant correlation is found between the nucleus and the host galaxy luminosity. Using the relationship between black hole mass (M BH ) and bulge luminosity we investigate the relation between M BH and total radio power for RLQs and compare it with other classes of radio sources. The overall distribution of active galactic nuclei in the M BH -P radio plane exhibits a trend for increasing M BH with increasing P radio but with a substantial spread. RLQs occupy the region of the most powerful sources and the most massive black hole. The quasars appear to emit over a wide range of power with respect to their Eddington luminosity, as deduced by the estimated M BH .

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What is the difference between radio-loud and radio-quiet quasi-stellar objects?

Cited by 43 publications

References 0 publications

Evidence for Merger Remnants in Early‐Type Host Galaxies of Low‐Redshift QSOs1

Evidence for Merger Remnants in Early‐Type Host Galaxies of Low‐Redshift QSOs1

TheHubble Space TelescopeSurvey of BL Lacertae Objects. II. Host Galaxies

Host Galaxies of Low‐zRadio‐loud Quasars: A Search ofHubble Space TelescopeArchives

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