J/ApJS/148/275 ASCA AGN optical identifications (Akiyama+, 2003)
Optical identification of the ASCA medium sensitivity survey in the
northern sky: nature of hard X-Ray-Selected luminous active galactic nuclei.
Akiyama M., Ueda Y., Ohta K., Takahashi T., Yamada T.
<Astrophys. J. Suppl. Ser. 148, 275 (2003)>
=2003ApJS..148..275A 2003ApJS..148..275A
ADC_Keywords: X-ray sources ; Active gal. nuclei ; Photometry, infrared ;
Equivalent widths
Keywords: diffuse radiation - galaxies: active - quasars: general - surveys -
X-rays: diffuse background
Abstract:
We present the results of optical spectroscopic identifications of a
bright subsample of 2-10keV hard X-ray-selected sources from the ASCA
Medium Sensitivity Survey in the northern sky (AMSSn). The flux limit
of the subsample is 3x10-13erg/s/cm2 in the 2-10keV band. All but
one of the 87 hard X-ray-selected sources are optically identified,
with AGNs (including broad-line AGNs, narrow-line AGNs, and three BL
Lac objects), seven clusters of galaxies, and one galactic star. It is
the largest complete sample of hard X-ray-selected AGNs at the bright
flux limit. Amounts of absorption to their nuclei are estimated to be
hydrogen column densities (NH) of up to 3x1023cm-2 from their
X-ray spectra. Optical properties of X-ray absorbed AGNs with
NH>1x1022cm-2 indicate the effects of dust absorption: at
redshifts z<0.6, AGNs without broad Hβ emission lines have
significantly larger NH-values than AGNs with broad Hβ emission
lines. At z>0.6, the X-ray absorbed AGNs have a large hard X-ray to
optical flux ratio (logf2-10keV/fR>+1). However, three X-ray
absorbed z>0.6 AGNs show strong broad lines. In combination with hard
X-ray-selected AGN samples from the ASCA Large Sky Survey, the ASCA
Deep Survey in the Lockman Hole, and Chandra Deep Field North, the
luminosity distributions of absorbed (NH>1x1022cm-2) and
less-absorbed (NH<1x1022cm-2) AGNs are compared.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 131 132 Candidates of optical counterparts and
results of identifications
table2.dat 103 87 Apparent properties of identified objects
table3.dat 63 86 Physical properties of identified objects or
absolute properties of identified objects
table4.dat 131 63 Optical emission-line properties of
identified objects
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See also:
J/PASJ/53/445 : ASCA Deep survey in Lockman Hole Field (Ishisaki+, 2001)
J/AJ/126/632 : UBVRIz'HK' photometry of 2Ms CDFN X-ray sources (Barger+, 2003)
J/AJ/126/539 : The Chandra Deep Fields North and South (Alexander+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [1AXG]
6- 17 A12 --- 1AXG 1AXG designation (JHHMMSS+DDMM)
19- 22 A4 --- ID Identification number
24- 27 F4.1 --- Det Detection significance in the GIS 2-10keV band
29- 30 I2 h RAh X-ray Right ascension (J2000.0)
32- 33 I2 min RAm X-ray Right ascension (J2000.0)
35- 39 F5.2 s RAs X-ray Right ascension (J2000.0)
41 A1 --- DE- X-ray Declination sign (J2000.0)
42- 43 I2 deg DEd X-ray Declination (J2000.0)
45- 46 I2 arcmin DEm X-ray Declination (J2000.0)
48- 52 F5.2 arcsec DEs X-ray Declination (J2000.0)
54- 57 F4.2 arcmin errPos Uncertainty of the X-ray source position
59- 63 A5 --- Nopt Identification number of the optical object
65- 66 I2 h RAoh Optical Right ascension (J2000.0)
68- 69 I2 min RAom Optical Right ascension (J2000.0)
71- 75 F5.2 s RAos Optical Right ascension (J2000.0)
77 A1 --- DEo- Optical Declination sign (J2000.0)
78- 79 I2 deg DEod Optical Declination (J2000.0)
81- 82 I2 arcmin DEom Optical Declination (J2000.0)
84- 87 F4.1 arcsec DEos Optical Declination (J2000.0)
89- 92 F4.2 arcmin Offset Distance between X-ray and optical sources
94- 97 F4.1 mag Rmag ? R magnitude from APM catalog,
unless otherwise noted
98 A1 --- n_Rmag [lm] Note on Rmag (3)
100-106 A7 --- Select Selection mode of candidates of optical
counterparts (4)
108 A1 --- --- [*] * for the optical object identified with
the X-ray source
110-124 A15 --- Class Classification of the optical object
126-130 F5.3 --- z ? Redshift of the optical objects
131 A1 --- u_z [?] Uncertainty flag on z
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Note (3): Note on Rmag:
l: magnitude determined by photometric observations with a CCD
camera on the UH 88 inch telescope
m: magnitude determined from the spectrophotometric data with
a correction of +0.6 mag
Note (4): Selection modes:
N: NVSS (Cat. VIII/65)
F: FIRST (Cat. VIII/71)
RH: ROSAT HRI (Cat. IX/28)
CH: Chandra follow-up observation (B/chandra)
XM: XMM-Newton follow-up observation. (B/xmm)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [1AXG]
6- 17 A12 --- 1AXG 1AXG designation (JHHMMSS+DDMM)
19- 22 A4 --- ID Identification number
24- 30 A7 --- Class Classification of the optical counterpart
32- 35 F4.1 10+20cm-2 NH Galactic hydrogen column density estimated
from the H I map by Dickey & Lockman,
1990ARA&A..28..215D 1990ARA&A..28..215D
37- 40 F4.1 ct/ks HCR Hard (2-10keV) band count rate (1)
42- 44 F3.1 ct/ks e_HCR rms uncertainty on HCR
46- 50 F5.1 ct/ks SCR Soft (0.7-2keV) band count rate (1)
52- 54 F3.1 ct/ks e_SCR rms uncertainty on SCR
56- 60 F5.2 --- Gamma 0.7-10keV band apparent photon index
determined from hardness ratio,
HR=(H-S)/(H+S)
62- 65 F4.2 --- e_Gamma rms uncertainty on Gamma
67- 70 F4.1 mag Rmag ? R magnitude of optical counterpart
72 A1 --- l_Jmag Limit flag on Jmag
73- 76 F4.1 mag Jmag ? J magnitude of optical counterpart
77- 78 A2 --- n_Jmag [NC ] NC: position is not covered in the
second incremental 2MASS catalog
80 A1 --- l_Hmag Limit flag on Jmag
81- 84 F4.1 mag Hmag ? H magnitude of optical counterpart
85- 86 A2 --- n_Hmag [NC ] NC: position is not covered in the
second incremental 2MASS catalog
88 A1 --- l_Ksmag Limit flag on Jmag
89- 92 F4.1 mag Ksmag ? Ks magnitude of optical counterpart
93- 94 A2 --- n_Ksmag [NC ] NC: position is not covered in the
second incremental 2MASS catalog
96-102 F7.2 mJy F1.4GHz ? Radio flux in the 1.4GHz from NVSS,
unless otherwise noted
103 A1 --- n_F1.4GHz [hij] Note on radio flux (3)
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Note (1): Count rate corrected for vignetting and Galactic absorption
Note (3): Note on radio flux:
h: Radio flux from FIRST catalog (Cat. VIII/71)
i: Radio flux from sum of two radio sources
j: Radio flux from sum of tree radio sources
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [1AXG]
6- 17 A12 --- 1AXG 1AXG designation (JHHMMSS+DDMM)
19- 22 A4 --- ID Identification number
24- 30 A7 --- Class Classification of the optical counterpart
32- 36 F5.2 [10-7W] logLHX ? Object-frame absorption-corrected 2-10keV
logarithmic luminosity (1)
38- 42 F5.2 [cm-2] logNH ? Best-fit object-frame logarithmic hydrogen
column density of absorbed power-law model
44- 49 F6.2 mag VMAG ? Absolute V magnitude
51 A1 --- l_logL1.4GHz Limit flag on logL1.4GHz
52- 56 F5.2 [W/Hz] logL1.4GHz Radio luminosity at 1.4GHz
58 A1 --- l_logR8.4GHz Limit flag on logP8.4GHz
59- 63 F5.2 --- logR8.4GHz Radio-to-optical luminosity ratio (2)
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Note (1): Object-frame absorption-corrected 2-10keV logarithmic luminosity
determined from the count rate in the hard X-ray band and the best-fit
absorbed power-law model.
Note (2): We use 8.4GHz radio luminosity and B-band optical absolute
magnitude. 8.4GHz radio luminosity and B-band absolute magnitude are
derived with power-law index of -0.5.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [1AXG]
6- 17 A12 --- 1AXG 1AXG designation (JHHMMSS+DDMM)
19- 22 A4 --- ID Identification number
24 A1 --- l_EW[OIII] Limit flag on EW[OIII] (1)
25- 30 F6.2 0.1nm EW[OIII] ? Equivalent width of [O III] λ5007
line
32- 35 F4.2 0.1nm e_EW[OIII] ? rms uncertainty on EW[OIII]
37 A1 --- l_EWHbN Limit flag on l_EWHbN (1)
38- 42 F5.2 0.1nm EWHbN Equivalent width of narrow Hβ line
44- 47 F4.2 0.1nm e_EWHbN ? rms uncertainty on EWHbN
49 A1 --- l_EWHbB Limit flag on EWHbB (1)
50- 54 F5.2 0.1nm EWHbB Equivalent width of broad Hβ line
56- 60 F5.2 0.1nm e_EWHbB ? rms uncertainty on EWHbB
62 A1 --- l_EW[NII] Limit flag on EW[NII] (1)
63- 67 F5.2 0.1nm EW[NII] ? Equivalent width of [N II] λ6583
line
69- 73 F5.2 0.1nm e_EW[NII] ? rms uncertainty on EW[NII]
75 A1 --- l_EWHaN Limit flag on EWHaN (1)
76- 80 F5.2 0.1nm EWHaN ? Equivalent width of narrow Hα line
82- 86 F5.2 0.1nm e_EWHaN ? rms uncertainty on EWHaN
88 A1 --- l_EWHaB ? Limit flag on l_EWHaB (1)
89- 94 F6.2 0.1nm EWHaB ? Equivalent width of broad Hα line
96-100 F5.2 0.1nm e_EWHaB ? rms uncertainty on EWHaB
103 A1 --- l_Rab Limit flag on Rab
104-107 F4.2 --- Rab ? Hα to Hβ broad emission-line
equivalent width ratio
109-112 F4.2 --- e_Rab ? rms uncertainty on Rab
114 A1 --- l_FWHM[OIII] Limit flag on FWHM[OIII] λ5007
115-118 I4 km/s FWHM[OIII] FWHM of [O III] line
120-124 I5 km/s FWHMHbB ? FWHM of Hβ line
127-131 I5 km/s FWHMHaB ? FWHM of Hα line
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Note (1): One σ upper limit is shown for object in which the
emission line is not detected.
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History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 24-Oct-2003