J/ApJ/679/962 Quasars with strong nitrogen emission lines (Jiang+, 2008)
A sample of quasars with strong nitrogen emission lines from the Sloan
Digital Sky Survey.
Jiang L., Fan X., Vestergaard M.
<Astrophys. J., 679, 962-966 (2008)>
=2008ApJ...679..962J 2008ApJ...679..962J
ADC_Keywords: QSOs ; Line Profiles
Keywords: galaxies: active - quasars: emission lines - quasars: general
Abstract:
We report on 293 quasars with strong NIV] λ1486 or NIII]
λ1750 emission lines (rest-frame equivalent width >3Å) at
1.7<z<4.0 selected from the Sloan Digital Sky Survey (SDSS) Fifth Data
Release (Cat. VII/252). These nitrogen-rich (N-rich) objects comprise
∼1.1% of the SDSS quasars. The comparison between the N-rich quasars
and other quasars shows that the two quasar subsets share many common
properties. We also confirm previous results that N-rich quasars have
much stronger Lyα and NV λ1240 emission lines. Strong
nitrogen emission in all ionization states indicates high overall
nitrogen abundances in these objects. We find evidence that the
nitrogen abundance is closely related to quasar radio properties.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 90 293 SDSS DR5 N-rich quasar catalog
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See also:
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
J/ApJ/613/129 : Equivalent widths of QSOs (Wise+, 2004)
J/MNRAS/354/L31 : SDSS DR2 QSO and DLA properties (Murphy+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SDSS]
6- 24 A19 --- SDSS Quasar identification (JHHMMSS.ss+DDMMSS.s)
26- 30 F5.3 --- z SDSS redshift
32- 36 F5.2 mag imag SDSS i band magnitude, corrected for Galactic
extinction.
38- 42 F5.2 --- alpha Power-law continuum slope
44- 46 F3.1 0.1nm [NIV] ? [NIV] (1486) equivalent width
48- 51 F4.1 0.1nm [NIII] ? [NIII] (1750) equivalent width
53- 56 F4.1 0.1nm SiIV ? SiIV (1396) equivalent width
58- 62 F5.1 0.1nm CIV ? CIV (1549) equivalent width
64- 67 F4.1 0.1nm [CIII] ? [CIII] (1909) equivalent width
69- 72 F4.1 0.1nm MgII ? MgII (2800) equivalent width
74- 76 F3.1 --- Fe/Mg ? The FeII/MgII ratio
78- 83 F6.2 mag 2500MAG Absolute AB mag at rest-frame 2500Å
85- 90 F6.1 --- R ? Radio loudness (2)
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Note (2): Defined by f(6cm)/f(2500), where f(6cm) is the observed flux
density at rest-frame 6cm derived from FIRST (if detected) assuming a
power-law slope of -0.5 and f(2500) is the monochromatic flux density
at rest-frame 2500Å.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 11-Oct-2010