J/MNRAS/410/860 Redshift dependence of BAL QSOs (Allen+, 2011)
A strong redshift dependence of the broad absorption line quasar fraction.
Allen J.T., Hewett P.C., Maddox N., Richards G.T., Belokurov V.
<Mon. Not. R. Astron. Soc., 410, 860-884 (2011)>
=2011MNRAS.410..860A 2011MNRAS.410..860A
ADC_Keywords: QSOs ; Spectroscopy
Keywords: methods: data analysis - galaxies: active - galaxies: nuclei -
quasars: absorption lines - galaxies: statistics
Abstract:
We describe the application of non-negative matrix factorization to
generate compact reconstructions of quasar spectra from the Sloan
Digital Sky Survey (SDSS), with particular reference to broad
absorption line quasars (BALQSOs). BAL properties are measured for
SiIVλ1400, CIVλ1550, AlIIIλ1860 and
MgIIλ2800, resulting in a catalogue of 3547 BALQSOs. Two
corrections, based on extensive testing of synthetic BALQSO spectra,
are applied in order to estimate the intrinsic fraction of CIV
BALQSOs. First, the probability of an observed BALQSO spectrum being
identified as such by our algorithm is calculated as a function of
redshift, signal-to-noise ratio and BAL properties. Secondly, the
different completenesses of the SDSS target selection algorithm for
BALQSOs and non-BAL quasars are quantified.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 387 93400 Properties of the NMF reconstructions
(non-negative matrix factorization) and the
resulting broad absorption properties
--------------------------------------------------------------------------------
See also:
http://www.sdss.org : SDSS Home Page
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- SDSS SDSS name (HHMMSS.ss+DDMMSS.s)
20- 29 F10.6 deg RAdeg Right ascension in decimal degrees (J2000)
31- 40 F10.6 deg DEdeg Declination in decimal degrees (J2000)
42- 46 I5 d MJD SDSS MJD number
48- 51 I4 --- Plate SDSS plate number
53- 55 I3 --- Fiber SDSS fiber number
57- 62 F6.4 --- z Redshift
64- 69 F6.3 mag imag ?=9.999 SDSS i magnitude
72- 77 F6.3 --- S/N Signal-to-noise ratio at 1700Å (170nm)
79- 85 F7.3 [10mW/m2/nm] logF1700 ?=0.0 Flux density at 1700Å
(erg/s/cm2/Å)
87- 92 F6.3 [10-7W] logL1700 ?=0.0 Luminosity at 1700Å
[λLλ]
94 I1 --- HiZ [0/1] 1 if targeted as HIZ quasar in SDSS
96 I1 --- LowZ [0/1] 1 if targeted as LOWZ quasar in SDSS
98 I1 --- Prim [0/1] 1 if primary spectrum for an object
100 I1 --- Gen [0/1] 1 if object was used to generate
NMF components
102-103 I2 --- Nc Number of components used
105 I1 --- n_Nc [0/1] 1 if Nc is a reduction from the
number available
108-113 F6.3 --- chi2 ?=- Reduced chi2 value of the fit
115-118 I4 --- Npix Number of pixels retained after masking
120-125 F6.3 --- Slope ?=- Index of the power-law slope fitted to
identify red objects
127 I1 --- n_Slope [0/1] 1 if a slope correction was applied
129 I1 --- dip [0/1] 1 if an additional mask was applied
to cover a dip in the reconstruction
131 I1 --- man [0/1] 1 if defined manually
133-139 F7.1 km/s Si4BI ?=0 SiIV Balnicity index
141-145 F5.3 --- Si4d ?=0 SiIV Mean depth
147-152 I6 km/s Si4Vm ?=0 SiIV Minimum velocity
154-159 I6 km/s Si4VM ?=0 SiIV Maximum velocity
162-166 I5 km/s Si4Vcm ?=0 SiIV Minimum velocity covered by both
the SDSS spectra and NMF components
168-173 I6 km/s Si4VcM ?=0 SiIV Maximum velocity covered by both
the SDSS spectra and NMF components
175-177 I3 --- Si4BR ?=0 SiIV Number of bad pixels within the
BI integration range
180-181 I2 --- Si4BT ?=0 SiIV Number of bad pixels within any
BAL troughs
183-184 I2 --- Si4SR ?=0 SiIV Number of pixels affected by sky
lines within the BI integration range
186-187 I2 --- Si4ST ?=0 SiIV Number of pixels affected by
sky lines within any BAL troughs
189 I1 --- Si4Inc [0/1] 1 if the coverage of the BI region
is incomplete for SiIV
191 I1 --- Si4CBP [0/1] 1 if manual change has been made to
the measured BI and associated properties
because of bad pixels in the originally
identified trough for SiIV
193 I1 --- Si4CPF [0/1] 1 if manual change has been made
because of a poor NMF fit for SiIV
195 I1 --- Si4BBP [0/1] 1 if here is a broad region of bad
pixels that could be concealing a BAL
trough for SiIV
197-203 F7.1 km/s C4BI ?=0 CIV Balnicity index
205-209 F5.3 --- C4d ?=0 CIV Mean depth
211-216 I6 km/s C4Vm ?=0 CIV Minimum velocity
218-223 I6 km/s C4VM ?=0 CIV Maximum velocity
225-230 I6 km/s C4Vcm ?=0 CIV Minimum velocity covered by both
the SDSS spectra and NMF components
232-237 I6 km/s C4VcM ?=0 CIV Maximum velocity covered by both
the SDSS spectra and NMF components
239-241 I3 --- C4BR ?=0 CIV Number of bad pixels within the
BI integration range
244-245 I2 --- C4BT ?=0 CIV Number of bad pixels within any
BAL troughs
247-248 I2 --- C4SR ?=0 CIV Number of pixels affected by sky
lines within the BI integration range
250-251 I2 --- C4ST ?=0 CIV Number of pixels affected by
sky lines within any BAL troughs
253 I1 --- C4Inc [0/1] 1 if the coverage of the BI region
is incomplete for CIV
255 I1 --- C4CBP [0/1] 1 if manual change has been made to
the measured BI and associated properties
because of bad pixels in the originally
identified trough for CIV
257 I1 --- C4CPF [0/1] 1 if manual change has been made
because of a poor NMF fit for CIV
259 I1 --- C4BBP [0/1] 1 if here is a broad region of bad
pixels that could be concealing a BAL
trough for CIV
261-267 F7.1 km/s Al3BI ?=0 AlIII Balnicity index
269-273 F5.3 --- Al3d ?=0 AlIII Mean depth
275-280 I6 km/s Al3Vm ?=0 AlIII Minimum velocity
282-287 I6 km/s Al3VM ?=0 AlIII Maximum velocity
289-294 I6 km/s Al3Vcm ?=0 AlIII Minimum velocity covered by both
the SDSS spectra and NMF components
296-301 I6 km/s Al3VcM ?=0 AlIII Maximum velocity covered by both
the SDSS spectra and NMF components
303-305 I3 --- Al3BR ?=0 AlIII Number of bad pixels within the
BI integration range
309 I1 --- Al3BT ?=0 AlIII Number of bad pixels within any
BAL troughs
311-312 I2 --- Al3SR ?=0 AlIII Number of pixels affected by sky
lines within the BI integration range
314-315 I2 --- Al3ST ?=0 AlIII Number of pixels affected by
sky lines within any BAL troughs
317 I1 --- Al3Inc [0/1] 1 if the coverage of the BI region
is incomplete for AlIII
319 I1 --- Al3CBP [0/1] 1 if manual change has been made to
the measured BI and associated properties
because of bad pixels in the originally
identified trough for AlIII
321 I1 --- Al3CPF [0/1] 1 if manual change has been made
because of a poor NMF fit for AlIII
323 I1 --- Al3BBP [0/1] 1 if here is a broad region of bad
pixels that could be concealing a BAL
trough for AlIII
325-331 F7.1 km/s Mg2BI ?=0 MgII Balnicity index
333-337 F5.3 --- Mg2d ?=0 MgII Mean depth
339-344 I6 km/s Mg2Vm ?=0 MgII Minimum velocity
346-351 I6 km/s Mg2VM ?=0 MgII Maximum velocity
353-358 I6 km/s Mg2Vcm ?=0 MgII Minimum velocity covered by both
the SDSS spectra and NMF components
360-365 I6 km/s Mg2VcM ?=0 MgII Maximum velocity covered by both
the SDSS spectra and NMF components
367-369 I3 --- Mg2BR ?=0 MgII Number of bad pixels within the
BI integration range
373 I1 --- Mg2BT ?=0 MgII Number of bad pixels within any
BAL troughs
375-376 I2 --- Mg2SR ?=0 MgII Number of pixels affected by sky
lines within the BI integration range
378-379 I2 --- Mg2ST ?=0 MgII Number of pixels affected by
sky lines within any BAL troughs
381 I1 --- Mg2Inc [0/1] 1 if the coverage of the BI region
is incomplete for MgII
383 I1 --- Mg2CBP [0/1] 1 if manual change has been made to
the measured BI and associated properties
because of bad pixels in the originally
identified trough for MgII
385 I1 --- Mg2CPF [0/1] 1 if manual change has been made
because of a poor NMF fit for MgII
387 I1 --- Mg2BBP [0/1] 1 if here is a broad region of bad
pixels that could be concealing a
BAL trough for M gII
--------------------------------------------------------------------------------
History:
16-Sep-2011: From electronic version of the journal
20-Jul-2012: imag around -9. set to -9.999
(End) Patricia Vannier [CDS] 16-Aug-2011