J/ApJS/175/116 SNU bright quasar survey (SNUQSO) (Lee+, 2008)
Seoul national university bright quasar survey in optical (SNUQSO).
I. First phase observations and results.
Lee I., Im M., Kim M., Kang E., Shim H., Richards G.T., Edge A.C.,
Lee M.G., Park C., Park M.-G.
<Astrophys. J. Suppl. Ser., 175, 116-127 (2008)>
=2008ApJS..175..116L 2008ApJS..175..116L
ADC_Keywords: QSOs ; Spectroscopy ; Redshifts
Keywords: galaxies: active - galaxies: nuclei - quasars: emission lines
quasars: individual (SNUQSO J003236.59-091026.2) - surveys
techniques: spectroscopic
Abstract:
We present results from the first phase of the Seoul National
University Bright Quasar Survey in Optical (SNUQSO) as well as its
basic observational setup. Previous and current large-area surveys
have been successful in identifying many quasars, but they could have
missed bright quasars due to their survey design. In order to help
complete the census of bright quasars, we have performed spectroscopic
observations of new bright quasar candidates selected from various
methods based on optical colors, near-infrared colors, radio, and
X-ray data. In 2005/2006, we observed 55 bright quasar candidates
using the Bohyunsan Optical Echelle Spectrograph (BOES) on the 1.8m
telescope at the Bohyunsan Optical Astronomy Observatory in Korea. We
identify 14 quasars/Seyferts from our observation, including an
optically bright quasar with i=14.98mag at z=0.092 (SDSS
J003236.59-091026.2). Non-quasar/Seyfert objects are found to be
mostly stars, among which there are five M-type stars and one
cataclysmic variable. Our result shows that there still exist bright
quasars to be discovered. However, at the same time, we conclude that
finding new bright quasars in high Galactic latitude regions is very
challenging and that the existing compilation of optically bright
quasars is nearly complete in the northern hemisphere.
Description:
We observed quasar candidates with the long-slit, low-resolution mode
of Bohyunsan Optical Echelle Spectrograph (LSS; Kim et al. 2003, Publ.
Korean Astron. Soc., 18, 81) on the 1.8m telescope at the Bohyunsan
Optical Astronomy Observatory (BOAO), Korea, over four observing runs
spanning from 2005 January to 2006 December.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 75 55 Target summary
table3.dat 123 14 Properties of quasars
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See also:
J/AJ/130/873 : Properties of BQS objects in the SDSS DR3 area (Jester+, 2005)
J/A+A/427/387 : QORG catalog of radio/X-ray sources (Flesch+, 2004)
J/A+A/358/77 : Hamburg/ESO survey for bright QSOs. III. (Wisotzki+, 2000)
J/A+AS/112/347 : A Homogeneous Bright QSO Survey (Cristiani+, 1995)
J/AJ/109/1498 : Large Bright Quasar Survey VI (LBQS) (Hewett+, 1995)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- Name Name (JHHMMSS.ss+DDMMSS.s) (1)
21 A1 --- f_Name [d] Note on QORG J043737.4-022928 (4)
23- 37 A15 --- Type Type (3)
39 A1 --- f_Type [fg] Flag on Type (4)
41- 52 A12 --- Meth Candidates selection methods (5)
54 A1 --- f_Meth [h] Flag for SDSS J145426.43+181951.8 (4)
56- 60 F5.2 mag imag ? SDSS (AB) i band magnitude (7)
61 A1 --- f_imag [e] means extended source (7)
63- 66 F4.2 mag J-K ? 2MASS J-K color index
68- 71 A4 --- Group SDSS quasar selection method belonging (8)
73- 75 A3 --- Com Yes or No for objects also selected as a
quasar candidate in SDSS DR3 or DR4
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Note (1): Objects with a filled "Com" column are SDSS JHHMMSS.ss+DDMMSS.s
(note that the format is sometimes JHHMMSS.s+DDMMSS), others (4
objects) are 1RXS JHHMMSS.s+DDMMSS in Simbad.
Note (3): Classification is based on FWHM of the Hα line (>1000km/s
for quasar) and the i-band absolute magnitude (Mi←22.0 for quasars;
Schneider et al. 2003, Cat. J/AJ/126/2579, SDSS quasar catalog II,
obsoleted by Cat. VII/243).
Note (4): Note as follows:
d = QORG J043737.4-022928 A et B are different from each other.
We could not identify which one is the target since they are
located very close to each other.
f = Cataclysmic variable
g = The classification may represent that of a nearby bright star. See text.
h = For SDSS J145426.43+181951.8, a galaxy is located 12.06" from this
object. It is possible that this galaxy is the X-ray source since
the position accuracy of ROSAT is worse than 13".
Note (5): Selection methods are:
QORG = candidates selected from the Quasars.Org catalog by Flesch
& Hardcastle (2004, Cat. J/A+A/427/387)
x-ray source = candidates selected form ROSAT Bright Source Catalog (1RXS-B)
matched against 2MASS-PSC (Cat. II/246)
Optical = from SDSS DR3 (Cat. II/259, obsoleted by Cat. II/282)
Opt.+NIR = SDSS matched against 2MASS-PSC
Radio+NIR = NVSS (Condon et al. 1998, Cat. VIII/75) matched against
2MASS-PSC
Note (7): We use PSF magnitude for point sources and Petrosian magnitude
for extended sources. Photometric data are not corrected for Galactic
extinction.
Note (8): Group is:
A = quasar candidates selected via the "kernel density method" on the
SDSS DR3 (Richards et al., 2004, Cat. J/ApJS/155/257)
B = additional quasar candidates selected at i>14mag
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- Name Name (JHHMMSS.ss+DDMMSS.s) (1)
21- 25 F5.3 --- z Redshift
27- 31 F5.3 --- e_z ? Error on redshift
33- 36 I4 km/s WHa ? Full width at half-maximum in Hα
38- 41 I4 km/s e_WHa ? Error on FWHMHa
43- 46 I4 km/s WHb ? Full width at half-maximum in Hβ
48- 51 I4 km/s e_WHb ? Error on FWHMHb
53- 58 F6.2 aW/m2 F(Ha) ? Flux in Hα band (10-15erg/s/cm2)
60- 64 F5.2 aW/m2 e_F(Ha) ? Error on Hα luminosity flux
66- 71 F6.2 aW/m2 F(Hb) ? Flux in Hβ band
73- 77 F5.2 aW/m2 e_F(Hb) ? Error on Hβ luminosity flux
79- 85 F7.2 10+6solMass MBH ? Mass of Black Holes
87- 92 F6.2 10+6solMass E_MBH ? Positive error on BH mass
94- 99 F6.2 10+6solMass e_MBH ? Negative error on BH mass
101 A1 --- Com [YN] Yes = also noted as quasar in SDSS
103-104 A2 --- f_Rad Limit flag on Rad
105-108 F4.1 --- Rad Radio loudness (3)
110-115 F6.2 mag gMAG Absolute magnitude in SDSS g-band
116 A1 --- f_gMAG [c] indicates B-band magnitude
118-123 F6.2 mag iMAG ? Absolute magnitude in SDSS i-band
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Note (1): SNUQSO JHHMMSS.ss+DDMMSS.s in Simbad
Note (3): the radio loudness parameter is taken as the ratio of flux in
radio at 6cm versus optical flux at 4400Å
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 17-Jun-2009