J/ApJ/687/78 FeII emission in quasars (Hu+, 2008)
A systematic analysis of Fe II emission in quasars: evidence for inflow to the
central black hole.
Hu C., Wang J.-M., Ho L.C., Chen Y.-M., Zhang H.-T., Bian W.-H., Xue S.-J.
<Astrophys. J., 687, 78-96 (2008)>
=2008ApJ...687...78H 2008ApJ...687...78H
ADC_Keywords: Line Profiles ; Redshifts ; QSOs ; Equivalent widths
Keywords: galaxies: nuclei - line: profiles - quasars: emission lines -
quasars: general - galaxies: Seyfert
Abstract:
Broad FeII emission is a prominent feature of the optical and
ultraviolet spectra of quasars. We report on a systematical
investigation of optical FeII emission in a large sample of 4037 z<0.8
quasars selected from the SDSS-DR5 quasar catalog (Cat. VII/252). We
have developed and tested a detailed line-fitting technique, taking
into account the complex continuum and narrow and broad emission-line
spectra. Our primary goal is to quantify the velocity broadening and
velocity shift of the FeII spectrum in order to constrain the location
of the FeII-emitting region and its relation to the broad-line region.
We find that the majority of quasars show FeII emission that is
redshifted, typically by ∼400km/s, but up to 2000km/s, with respect to
the systemic velocity of the narrow-line region or of the conventional
broad-line region as traced by the Hβ line. Moreover, the line
width of FeII is significantly narrower than that of the broad
component of Hβ. We show that the magnitude of the FeII redshift
correlates inversely with the Eddington ratio, and that there is a
tendency for sources with redshifted FeII emission to show red
asymmetry in the Hβ line. These characteristics strongly suggest
that FeII originates from a location different from, and most likely
exterior to, the region that produces most of Hβ. The
FeII-emitting zone traces a portion of the broad-line region of
intermediate velocities whose dynamics may be dominated by infall.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 433 4037 Spectrophotometric measurements
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See also:
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
J/ApJ/674/668 : SDSS J102839.11+450009.4 Fe II emission lines (Wang+, 2008)
J/ApJ/683/L115 : Intermediate-line region in quasars (Hu+, 2008)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- SDSS SDSS DR5 designation (HHMMSS.ss+DDMMSS.s)
20- 26 F7.4 --- z Redshift determined using peak of [OIII]5007
28- 38 E11.4 10-7W L(Fe) Luminosity of FeII emission between
4434 & 4686 Angstroms
40- 50 E11.4 10-7W e_L(Fe) Error in L(Fe)
52- 58 F7.1 km/s W(Fe) FeII FWHM
60- 66 F7.1 km/s e_W(Fe) Error in FWHM(Fe)
68- 74 F7.1 km/s v(Fe) FeII velocity shift (1)
76- 82 F7.1 km/s e_v(Fe) Error in v(Fe) (1)
84- 94 E11.4 10-7W L(HbB) Broad Hβ component luminosity
96-106 E11.4 10-7W e_L(HbB) Error in L(HbB)
108-114 F7.1 km/s W(HbB) Broad Hβ component FWHM
116-122 F7.1 km/s e_W(HbB) Error in W(HbB)
124-130 F7.1 km/s v(HbB) Broad Hβ component velocity shift (1)
132-138 F7.1 km/s e_v(HbB) Error in v(HbB) (1)
140-150 E11.4 uW/nm L5100 Specific continuum luminosity at 5100Å
(in erg/s/Å)
152-162 E11.4 uW/nm e_L5100 Error in L5100
164-169 F6.3 --- alpha Power law spectral index of continuum
[F(λ)∝λα)
171-176 F6.3 --- e_alpha Error in alpha
178 A1 --- l_L6cm Upper limit flag on L6cm
179-188 E10.3 10-7W/Hz L6cm ?=-1 Specific luminosity at 6cm (2)
190-199 E10.3 10-7W/Hz L2kev ?=0 Specific luminosity at 2kev (3)
201-211 E11.4 10-7W L(Mg) ?=-9999 MgII luminosity
213-223 E11.4 10-7W e_L(Mg) ?=-9999 Error in L(Mg)
225-231 F7.1 km/s W(Mg) ?=-9999 MgII FWHM
233-239 F7.1 km/s e_W(Mg) ?=-9999 Error in W(Mg)
241-247 F7.1 km/s v(Mg) ?=-9999 MgII velocity shift (1)
249-255 F7.1 km/s e_v(Mg) ?=-9999 Error in v(Mg) (1)
257-267 E11.4 10-7W L(OIII) OIIIλ5007 luminosity
269-279 E11.4 10-7W e_L(OIII) Error in L(OIII)
281-287 F7.1 km/s W(OIII) OIIIλ5007 FWHM
289-295 F7.1 km/s e_W(OIII) Error in W(OIII)
297-307 E11.4 --- HbN/OIII Ratio of HβNC to OIIIλ5007
309-319 E11.4 --- e_HbN/OIII Error in HbN/OIII
321-327 F7.1 km/s v(HbN) HbNC velocity shift (1)
329-335 F7.1 km/s e_v(HbN) Error in v(HbN) (1)
337-347 E11.4 10-7W L(OII) ?=-9999 OII luminosity
349-359 E11.4 10-7W e_L(OII) ?=-9999 Error in L(OII)
361-367 F7.1 km/s W(OII) ?=-9999 OII FWHM
369-375 F7.1 km/s e_W(OII) ?=-9999 Error in W(OII)
377-383 F7.1 km/s v(OII) ?=-9999 OII velocity shift (1)
385-391 F7.1 km/s e_v(OII) ?=-9999 Error in v(OII) (1)
393-399 F7.1 km/s sigHb Square root of second moment of HβBC
401-410 E10.3 solMass MBH Mass of the central Black Hole
412-421 E10.3 --- Lb/LEd Ratio of bolometric to Eddtington luminosity
423-433 E11.4 --- FeII/HbB Ratio of FeII to HβBC
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Note (1): All emission line velocity shifts are with respect to [OIII]5007,
and a positive velocity indicates a red ward shift.
Note (2): Derived from Peak flux density measured in FIRST, assuming a radio
spectral index =-0.5; the upper limits are derived from the FIRST
flux limits. -1.000 indicates not in FIRST survey area.
Note (3): Derived from ROSAT PSPC count rate.
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History:
From electronic version of the journal
References:
Hu et al. Paper II. 2008ApJ...683L.115H 2008ApJ...683L.115H Cat J/ApJ/683/L115.
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 25-Nov-2010