J/ApJ/769/95 [NeV] or [NeIII] double peaked SDSS quasars (Barrows+, 2013)
Identification of outflows and candidate dual active galactic nuclei in
SDSS quasars at z = 0.8-1.6.
Barrows R.S., Lacy C.H.S., Kennefick J., Comerford J.M., Kennefick D.,
Berrier J.C.
<Astrophys. J., 769, 95 (2013)>
=2013ApJ...769...95B 2013ApJ...769...95B
ADC_Keywords: Spectroscopy ; QSOs ; Redshifts ; Active gal. nuclei
Keywords: galaxies: active; galaxies: high-redshift; galaxies: jets;
galaxies: nuclei; quasars: emission lines
Abstract:
We present a sample of 131 quasars from the Sloan Digital Sky Survey
at redshifts 0.8<z<1.6 with double peaks in either of the
high-ionization narrow emission lines [NeV]λ3426 or
[NeIII]λ3869. These sources were selected with the intention of
identifying high-redshift analogs of the z<0.8 active galactic nuclei
(AGNs) with double-peaked [OIII]λ5007 lines, which might
represent AGN outflows or dual AGNs. Lines of high ionization
potential are believed to originate in the inner, highly photoionized
portion of the narrow line region, and we exploit this assumption to
investigate the possible kinematic origins of the double-peaked lines.
For comparison, we measure the [NeV]λ3426 and
[NeIII]λ3869 double peaks in low-redshift (z<0.8)
[OIII]-selected sources. We find that [NeV]λ3426 and
[NeIII]λ3869 show a correlation between line splitting and line
width similar to that of [OIII]λ5007 in other studies, and the
velocity splittings are correlated with the quasar Eddington ratio.
These results suggest an outflow origin for at least a subset of the
double peaks, allowing us to study the high-ionization gas kinematics
around quasars. However, we find that a non-negligible fraction of our
sample show no evidence for an ionization stratification. For these
sources, the outflow scenario is less compelling, leaving the dual AGN
scenario as a viable possibility. Finally, we find that our sample
shows an anti-correlation between the velocity-offset ratio and
luminosity ratio of the components, which is a potential dynamical
argument for the presence of dual AGNs. Therefore, this study serves
as a first attempt at extending the selection of candidate dual AGNs
to higher redshifts.
Description:
Our parent sample consists of archival spectra drawn from the quasar
catalog of the SDSS Data Release 7 (DR7) which is described in detail
in Schneider et al. (2010, Cat. VII/260). The typical resolution of
the SDSS spectra is λ/Δλ∼2000.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 85 80 Emission line properties for double-peaked
[Ne V] λ3426
table2.dat 85 89 Emission line properties for double-peaked
[Ne III] λ3869
table3.dat 75 131 General quasar properties for our sample
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See also:
VII/270 : SDSS quasar catalog: tenth data release (Paris+, 2014)
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
J/ApJS/201/31 : Emission-line galaxies from SDSS. I. (Ge+, 2012)
J/AJ/144/125 : Phot. and spectro. of Markarian 266 (Mazzarella+, 2012)
J/ApJ/753/42 : Double-peaked AGN. I. Dual AGN candidates (Comerford+, 2012)
J/ApJ/737/101 : AGN pairs from SDSS-DR7. I. (Liu+, 2011)
J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)
J/ApJ/716/866 : SDSS search for binary AGN (Smith+, 2010)
J/ApJ/708/427 : Type 2 AGNs with double-peaked [OIII] lines (Liu+, 2010)
J/MNRAS/405/2302 : Improved redshifts for SDSS quasar spectra (Hewett+, 2010)
J/ApJ/705/L76 : AGNs with double-peaked [OIII] lines (Wang+, 2009)
J/ApJS/166/470 : SDSS-Spitzer type I QSOs IR photometry (Richards+, 2006)
J/A+A/417/515 : I Zw 1 unusual emission line spectrum (Veron-Cetty+, 2004)
J/AJ/126/1720 : ugriz and Hα of double-peaked AGN (Strateva+, 2003)
J/AJ/126/1183 : Major galaxy mergers at z≲3 (Conselice+, 2003)
J/ApJ/599/886 : Emission lines of radio-loud AGN (Eracleous+, 2003)
Byte-by-byte Description of file: table[12].dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- SDSS SDSS name
21- 25 F5.1 10-19W/m2/nm Fb [4/150] Flux density; blue component (1)
27- 29 I3 10-19W/m2/nm e_Fb The 1σ uncertainty in Fluxb (1)
31- 34 I4 km/s dVb [-47/2387] Velocity offset from the
quasar redshift; blue component
36- 38 I3 km/s e_dVb [0/327] The 1σ uncertainty in dVb
40- 43 I4 km/s FWHMb Full Width at Half Maximum; blue component
45- 47 I3 km/s e_FWHMb The 1σ uncertainty in FWHMb
49- 53 F5.1 10-19W/m2/nm Fr [5/245] Flux density; red component (1)
55- 57 I3 10-19W/m2/nm e_Fr The 1σ uncertainty in Fluxr (1)
59- 62 I4 km/s dVr [-831/721] Velocity offset from the
quasar redshift; red component
64- 66 I3 km/s e_dVr The 1σ uncertainty in dVr
68- 71 I4 km/s FWHMr Full Width at Half Maximum; red component
73- 75 I3 km/s e_FWHMr The 1σ uncertainty in FWHMr
77 I1 --- Br Broad component? 0='no', 1='yes'
79- 82 F4.2 --- chi2 [0.3/2.5] Reduced χ-squared
84- 85 I2 --- dof [10/92] Number of degrees of freedom
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Note (1): In units of 10-17 erg/s/cm2/Å.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- SDSS SDSS quasar name
21- 26 F6.4 --- zsdss [0.8/1.6] SDSS redshift
28- 33 F6.4 --- e_zsdss [0.0009/0.006] Error in zsdss
35- 40 F6.4 --- zmgii [0.8/1.6] MgII redshift
42- 47 F6.4 --- e_zmgii [0.001/0.02] Error in zmgii
49- 52 I4 km/s FWHMfeii Fe II Full Width at Half Maximum
54- 60 F7.2 km/s FWHMmgii [1460/9828] Mg II FWHM (1)
62- 69 F8.2 km/s e_FWHMmgii Error in FWHMmgii
71- 75 F5.3 --- fedd Eddington Ratio as described in Section 5.2
(fEdd=Lbol/LEdd)
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Note (1): From the SDSS DR7 Catalog of Quasar Properties
(Shen et al. 2011, J/ApJS/194/45).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 15-Dec-2014