J/A+A/620/A118 Highly Accreting Quasars: SDSS Low z Catalog (Negrete+, 2018)
Highly accreting quasars: The SDSS low-redshift catalog.
Negrete C.A., Dultzin D., Marziani P., Esparza D., Sulentic J. W.,
del Olmo A., Martinez-Aldama M. L., Garcia-Lopez A., D'Onofrio M, Bon N.
Bon E.
<Astron. Astrophys. 620, A118 (2018)>
=2018A&A...620A.118N 2018A&A...620A.118N (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; QSOs ; Redshifts ; Spectroscopy
Keywords: catalogs - galaxies: active - galaxies: distances and redshifts -
galaxies: nuclei - quasars: emission lines - quasars: general
Abstract:
The most highly accreting quasars are of special interest in studies
of the physics of active galactic nuclei (AGNs) and host galaxy
evolution. Quasars accreting at high rates (L/LEdd∼1) hold promise for
use as "standard candles": distance indicators detectable at very high
redshift. However, their observational properties are still largely
unknown.
We seek to identify a significant number of extreme accretors. A large
sample can clarify the main properties of quasars radiating near
L/LEdd∼1 (in this paper they are designated as extreme Population A
quasars or simply as extreme accretors) in the Hβ spectral range
for redshift ≲0.8.
We use selection criteria derived from four-dimensional Eigenvector 1
(4DE1) studies to identify and analyze spectra for a sample of 334
candidate sources identified from the SDSS DR7 database. The source
spectra were chosen to show a ratio RFeII between the FeII emission
blend at λ4570 and Hβ, RFeII > 1. Composite spectra were
analyzed for systematic trends as a function of FeII strength, line
width, and [OIII] strength. We introduced tighter constraints on the
signal-to-noise ratio (S/N) and RFeII values that allowed us to
isolate sources most likely to be extreme accretors.
We provide a database of detailed measurements. Analysis of the data
allows us to confirm that Hβ shows a Lorentzian function with a
full width at half maximum (FWHM) of Hβ≤4000km/s. We
find no evidence for a discontinuity at 2000km/s in the 4DE1,
which could mean that the sources below this FWHM value do not belong
to a different AGN class. Systematic [OIII] blue shifts, as well as a
blueshifted component in Hβ are revealed. We interpret the
blueshifts as related to the signature of outflowing gas from the
quasar central engine. The FWHM of Hβ is still affected by the
blueshifted emission; however, the effect is non-negligible if the
FWHM Hβ is used as a "virial broadening estimator" (VBE). We
emphasize a strong effect of the viewing angle on Hβ broadening,
deriving a correction for those sources that shows major disagreement
between virial and concordance cosmology luminosity values.
The relatively large scatter between concordance cosmology and virial
luminosity estimates can be reduced (by an order of magnitude) if a
correction for orientation effects is included in the FWHM Hβ
value; outflow and sample definition yield relatively minor effects.
Description:
Table 4: contains 103 spectra with an erroneous z identification.
The redshift values are given by: the SDSS database (erroneous
values), Shen et al. (2011, Cat. J/ApJS/194/45) and Hewett & Wilde
(2010, Cat. J/MNRAS/405/2302) (correct values).
Table 5: Contains the data described in the Table 2, which are the
measurements of the individual spectral fits and derived computations.
A detailed description of this table is in Sec. 4.2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 51 101 Objects with an erroneous z identification
table2.dat 543 302 Measurements of the individual spectral fits
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See also:
J/MNRAS/405/2302 : Improved redshifts for SDSS quasar spectra (Hewett+, 2010)
J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- SDSS SDSS Name
21- 27 F7.5 --- zSDSS SDSS DR7 redshift
29- 35 F7.5 --- e_zSDSS SDSS redshift error
37- 43 F7.5 --- zShen Shen et al. (2011, Cat. J/ApJS/194/45) redshift
45- 51 F7.5 --- zHW Hewitt & Wilde (2010, Cat. J/MNRAS/405/2302)
redshift
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- SDSS SDSS DR7 designation
21- 27 F7.5 --- z Redshift considered in this work (1)
29- 35 F7.5 --- e_z Redshift error
37- 43 F7.5 --- zSDSS Redshift SDSS DR7
45- 51 F7.5 --- e_zSDSS Redshift SDSS DR7 error
53- 57 F5.2 --- S/N S/N ratio measured around 5100Å
59- 62 F4.2 10-19W/m2/nm C5100 Continuum flux at 5100Å
in 10-17erg/cm2/s/Å
64- 67 F4.2 10-19W/m2/nm e_C5100 Continuum flux at 5100Å error
69- 73 F5.1 --- N5100 Continuum normalization at 5100Å
75- 79 F5.2 --- e_N5100 Continuum normalization at 5100Å
error
81- 85 F5.2 --- alpha Power law index
87- 90 F4.2 --- e_alpha Power law index error
92 I1 --- FaintHG Faint contribution of the HG
94-101 F8.2 10-20W/m2 FHbBC HβBC line flux
in 10-17erg/cm2/s
103-109 F7.2 10-20W/m2 e_FHbBC HβBC line flux error
111-115 F5.2 0.1nm EWHbBC HβBC rest-frame equivalent
width
117-121 F5.2 0.1nm e_EWHbBC HβBC rest-frame equivalent
width error
123-127 I5 km/s ShiftHbBC HβBC shift with respect to
the rest-frame
129-133 F5.1 km/s e_ShiftHbBC HβBC shift with respect to
the rest-frame error
135-142 F8.3 km/s FWHMHbBC HβBC FWHM
144-151 F8.3 km/s e_FWHMHbBC HβBC FWHM error
153 A1 --- Hbprofile [GL] G = Gaussian, L = Lorentzian
155-161 F7.2 10-20W/m2 FHbblue HβBLUE Line Flux
163-168 F6.2 10-20W/m2 e_FHbblue HβBLUE Line Flux error
170-174 F5.2 0.1nm EWHbblue HβBLUE rest-frame equivalent
width
176-179 F4.2 0.1nm e_EWHbblue HβBLUE rest-frame equivalent
width error
181-188 F8.2 km/s ShiftHbblue HβBLUE shift
190-196 F7.2 km/s e_ShiftHbblue HβBLUE shift error
198-201 I4 km/s FWHMHbblue HβBLUE FWHM
203-206 I4 km/s e_FWHMHbblue HβBLUE FWHM error
208-215 F8.2 10-20W/m2 FFeII FeII flux
217-223 F7.2 10-20W/m2 e_FFeII FeII flux error
225-230 F6.2 0.1nm EWFeII FeII rest-frame equivalent width
232-235 F4.1 0.1nm e_EWFeII FeII rest-frame equivalent width
error
237-240 A4 --- Pop Population designation
242-246 F5.3 --- RFeII Ratio between the FeII emission blend
at λ4570 and Hβ
248-252 F5.3 --- e_RFeII RFeII error
254-259 F6.3 --- AIHb Hβ asymetry (only objects with
Hbblue)
261-265 F5.3 --- e_AIHb Hβ asymetry error
267-270 F4.2 --- Kurt Kurtosis
272-275 F4.2 --- e_Kurt Kurtosis error
277-281 I5 km/s C010 Hβ centroid at 0.10 of the
line intensity
283-286 I4 km/s e_C010 Hβ centroid at 0.10 of the
line intensity error
288-291 I4 km/s C025 Hβ centroid at 0.25 of the
line intensity
293-295 I3 km/s e_C025 Hβ centroid at 0.25 of the
line intensity error
297-300 I4 km/s C050 Hβ centroid at 0.50 of the
line intensity
302-304 I3 km/s e_C050 Hβ centroid at 0.50 of the
line intensity error
306-309 I4 km/s C075 Hβ centroid at 0.75 of the
line intensity
311-313 I3 km/s e_C075 Hβ centroid at 0.75 of the
line intensity error
315-318 I4 km/s C090 Hβ centroid at 0.90 of the
line intensity
320-322 I3 km/s e_C090 Hβ centroid at 0.90 of the
line intensity error
324-329 F6.2 10-20W/m2 FHeII HeII line flux
331-335 F5.2 10-20W/m2 e_FHeII HeII line flux error
337-344 F8.2 km/s ShiftHeII HeII shift with respect to the
rest frame
346-352 F7.2 km/s e_ShiftHeII HeII shift with respect to the
rest frame error
354-357 I4 km/s FWHMHeII HeII FWHM
359-362 I4 km/s e_FWHMHeII HeII FWHM error
364-369 F6.2 10-20W/m2 FHbNC HβNC Line Flux
371-375 F5.2 10-20W/m2 e_FHbNC HβNC Line Flux error
377-380 F4.2 0.1nm EWHbNC HβNC rest-frame equivalent
width
382-385 F4.2 0.1nm e_EWHbNC HβNC rest-frame equivalent
width error
387-388 I2 km/s ShiftHbNC HβNC shift with respect to
the rest-frame
390-394 F5.1 km/s e_ShiftHbNC HβNC shift with respect to
the rest-frame error
396-399 I4 km/s FWHMHbNC HβNC FWHM
401-403 I3 km/s e_FWHMHbNC HβNC FWHM error
405-411 F7.2 10-20W/m2 FOIII Line flux of [OIII] 5007
413-419 F7.2 10-20W/m2 e_FOIII Line flux error of [OIII] 5007
421-425 F5.2 0.1nm EWOIII Line [OIII] 5007 rest-frame
equivalent width
427-431 F5.2 0.1nm e_EWOIII Line [OIII] 5007 rest-frame
equivalent width error
433-440 F8.2 km/s ShiftOIII Line [OIII] 5007 shift with respect
to the rest-frame
442-447 F6.2 km/s e_ShiftOIII Line [OIII] 5007 shift with respect
to the rest-frame error
449-452 I4 km/s FWHMOIII Line [OIII] 5007 FWHM
454-457 I4 km/s e_FWHMOIII Line [OIII] 5007 FWHM error
459-465 F7.2 10-20W/m2 FOIIISB Semi broad line [OIII] 5007 flux
467-473 F7.2 10-20W/m2 e_FOIIISB Semi broad line [OIII] 5007 flux
error
475-479 F5.2 0.1nm EWOIIISB Semi broad line [OIII] 5007
rest-frame equivalent width
481-485 F5.2 0.1nm e_EWOIIISB Semi broad line [OIII] 5007
rest-frame equivalent width error
487-494 F8.2 km/s ShiftOIIISB Semi broad line [OIII] 5007 shift
with respect to the rest frame
496-501 F6.2 km/s e_ShiftOIIISB Semi broad line [OIII] 5007 shift
with respect to the rest frame error
503-506 I4 km/s FWHMOIIISB Semi broad line [OIII] 5007 FWHM
508-511 I4 km/s e_FWHMOIIISB Semi broad line [OIII] 5007 FWHM
error
513-516 F4.2 [Msun] logMBH Black hole mass
518-521 F4.2 [Msun] e_logMBH Black hole mass error
523-527 F5.2 [Lsun] logLBol Bolometric luminosity
529-532 F4.2 [Lsun] e_logLBol Bolometric luminosity error
534-538 F5.2 --- L/LEdd Eddington ratio
540-543 F4.2 --- e_L/LEdd Eddington ratio error
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Note (1): measured using the HβNC or [OIII]λ5007 line (see text).
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Acknowledgements:
Alenka Negrete, alenka(at)astro.unam.mx
(End) Patricia Vannier [CDS] 10-Sep-2018