J/AJ/127/646 Unbiased census of AGN in 2MASS (Francis+, 2004)
An unbiased census of active galactic nuclei in the Two Micron All Sky Survey.
Francis P.J., Nelson B.O., Cutri R.M.
<Astron. J., 127, 646-655 (2004)>
=2004AJ....127..646F 2004AJ....127..646F
ADC_Keywords: Active gal. nuclei ; QSOs ; Surveys ; Redshifts ;
Equivalent widths
Keywords: galaxies: active - quasars: general - surveys
Abstract:
We present an unbiased near-IR-selected AGN sample, covering
12.56deg2 down to Ks∼15.5, selected from the Two Micron All Sky
Survey (2MASS). Our only selection effect is a moderate color cut
(J-Ks>1.2) designed to reduce contamination from Galactic stars. We
observed both pointlike and extended sources.
Description:
We observed spectra of sources in four fields on the nights of 2002
March 5-7. Each field was circular and 1° in radius. The fields
were centered at 09:44+00:00, 12:44+00:00, 13:00-25:00, and
14:15-26:00 (J2000.0).
Observations were carried out with the Two Degree Field (2dF)
spectrograph on the Anglo-Australian Telescope.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table5.dat 74 968 All Galaxies with Secure Redshifts
--------------------------------------------------------------------------------
See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 h RAh 2MASS hour of right ascension (J2000)
4- 5 I2 min RAm 2MASS minute of right ascension (J2000)
7- 11 F5.2 s RAs 2MASS second of right ascension (J2000)
13 A1 --- DE- Sign of the 2MASS declination (J2000)
14- 15 I2 deg DEd 2MASS degree of declination (J2000)
17- 18 I2 arcmin DEm 2MASS arcminute of declination (J2000)
20- 23 F4.1 arcsec DEs 2MASS arcsecond of declination (J2000)
25- 30 F6.4 --- z Redshift
32 A1 --- q_z Quality flag on z (1)
34- 37 A4 --- Class Spectral classification (2)
39- 42 F4.1 mag Ksmag The 2MASS Ks band magnitude
44- 47 F4.2 mag J-K The 2MASS (J-Ks) color
49- 53 F5.1 nm Ha ? Rest-frame Hα equivalent width (3)
55- 58 F4.1 nm Hb ? Rest-frame Hβ equivalent width (3)
60- 64 F5.1 nm [OIII] ? Rest-frame [OIII] equivalent width (3)
66- 69 F4.1 nm NII ? Rest-frame NII equivalent width (3)
71- 74 F4.1 nm SII ? Rest-frame SII equivalent width (3)
--------------------------------------------------------------------------------
Note (1): Values of 4 or higher are considered reliable.
Only galaxies with reliable redshifts are shown.
Note (2): Spectral classification:
gal = Galaxy without noticable emission lines.
sb = Galaxy with emission-line ratios typical of a starburst. A question
mark indicates a classification based on lines near Hα only.
sy1 = Galaxy with broad (>1000km/s FHWM) emission lines.
sy2 = Galaxy with narrow emission lines, with ratios typical of an AGN.
A question mark indicates a classification based on lines near
Hα only.
gem = Galaxy with narrow emission lines that could not be classified
as a starburst or AGN.
Note (3): Wavelength regions used in emission-line measurements:
----------------------------------------------------------------
Line Continuum Integration Limits Line Integration Limits
(nm) (nm)
----------------------------------------------------------------
Hβ 474.0-484.0, 488.0-494.0 484.5-488.0
[OIII] 488.0-494.0, 503.0-510.0 499.0-502.5
Hα 640.0-652.0, 663.0-670.0 655.0-657.2
NII 640.0-652.0, 663.0-670.0 657.2-659.4
[SII] 663.0-670.0, 674.5-684.5 670.0-674.5
----------------------------------------------------------------
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 02-Jul-2004