J/ApJ/703/2160 The OPTX project. III. (Trouille+, 2009)
The OPTX project.
III. X-ray versus optical spectral type for active galactic nuclei.
Trouille L., Barger A.J., Cowie L.L., Yang Y., Mushotzky R.F.
<Astrophys. J., 703, 2160-2170 (2009)>
=2009ApJ...703.2160T 2009ApJ...703.2160T
ADC_Keywords: X-ray sources ; Surveys ; Redshifts ; Active gal. nuclei
Keywords: cosmology: observations - galaxies: active
Abstract:
We compare the optical spectral types with the X-ray spectral
properties for a uniformly selected (sources with fluxes greater
than the 3σ level and above a flux limit of
f(2-8keV)>3.5x10-15erg/cm2/s), highly spectroscopically complete
(>80% for f(2-8keV)>10-14erg/cm2/s and >60% below) 2-8keV X-ray
sample observed in three Chandra fields (CLANS, CLASXS, and the CDF-N)
that cover ∼1.2deg2. For our sample of 645 spectroscopically
observed sources, we confirm that there is significant overlap of the
X-ray spectral properties, as determined by the effective photon
indices, Γeff, obtained from the ratios of the 0.5-2keV to
2-8keV counts, for the different optical spectral types. Thus, one
cannot use the X-ray spectral classifications and the optical spectral
classifications equivalently. Since it is not understood how X-ray and
optical classifications relate to the obscuration of the central
engine, we strongly advise against a mixed classification scheme, as
it can only complicate the interpretation of X-ray AGN samples.
Description:
Trouille et al. (2008, Cat. J/ApJS/179/1) present the details of our
spectroscopic observations of the X-ray sources in the CLANS, CLASXS,
and CDF-N fields, including how the observations were made, the data
reduction process, and the latest redshift catalogs. We provide a
catalog of only updated values for the CLANS field.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 120 53 CLANS (Chandra Lockman Area North Survey) catalog,
updated sources
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-)
J/ApJS/179/1 : The OPTX project: CLANS, CLASXS and CDF-N (Trouille+, 2008)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- CLANS Object identification (1)
5- 12 F8.4 deg RAdeg Right ascension in decimal degrees (J2000)
14- 20 F7.4 deg DEdeg Declination in decimal degrees (J2000)
22- 27 F6.2 ct Scts Net soft counts in the 0.5-2keV band
29- 33 F5.2 ct E_Scts 1σ positive error in Scts (2)
35- 39 F5.2 ct e_Scts 1σ negative error in Scts (2)
41- 46 F6.2 ct Hcts Net hard counts in the 2-8keV band
48- 52 F5.2 ct E_Hcts 1σ positive error in Hcts (2)
54- 58 F5.2 ct e_Hcts 1σ negative error in Hcts (2)
60- 64 F5.2 aW/m2 Fsoft X-ray flux in the 0.5-2keV in units of
10-15erg/cm2/s = 10-18W/m2
66- 69 F4.2 aW/m2 E_Fsoft 1σ positive error in Fsoft (2)
71- 74 F4.2 aW/m2 e_Fsoft 1σ negative error in Fsoft (2)
76- 80 F5.2 aW/m2 Fhard X-ray flux in the 2-8keV in units of
10-15erg/cm2/s = 10-18W/m2
82- 87 F6.2 aW/m2 E_Fhard 1σ positive error in Fhard (2)
89- 93 F5.2 aW/m2 e_Fhard 1σ negative error in Fhard (2)
95-100 F6.2 aW/m2 Ftot X-ray flux in the 0.5-8keV in units of
10-15erg/cm2/s = 10-18W/m2
102-105 F4.2 aW/m2 E_Ftot 1σ positive error in Ftot (2)
107-110 F4.2 aW/m2 e_Ftot 1σ negative error in Ftot (2)
112-116 F5.2 --- zsp ?=0 Spectroscopic redshift
118-120 I3 --- Class Optical spectral classification (3)
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Note (1): We ordered the sources by increasing right ascension and labeled
each with the same source number as in Trouille et al. (2008, Cat.
J/ApJS/179/1). CLANS No. 761 through No. 789 were inadvertently not
included in the original Trouille et al. (2008, Cat. J/ApJS/179/1)
CLANS catalog and so are included here. CLANS Nos. 80, 150, and 404 in
the Trouille et al. (2008, Cat. J/ApJS/179/1) catalog had incorrect
2-8keV fluxes as a result of their anomalously high HR values. Here,
we list their corrected fluxes determined using the HEASARC WebPIMMS
tool and assuming Γ=1.4. The remaining sources are included as
a result of our spectroscopic observations with DEIMOS on Keck II in
Spring 2009.
Note (2): The errors quoted are the 1σ Poisson errors, using the
approximations from Gehrels (1986ApJ...303..336G 1986ApJ...303..336G). The flux errors do
not include the uncertainty in the flux conversion factor; however,
the errors are generally dominated by the Poisson errors.
Note (3): Class as follows:
-99 = source spectroscopically observed but neither the redshift nor the class
could be identified
-1 = source not yet spectroscopically observed
-2 = source is a star
0 = absorber;
1 = star former;
3 = high-excitation source;
4 = BLAGN (broad-line active galactic nucleus).
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History:
From electronic version of the journal
References:
Trouille et al. Paper I. 2008ApJS..179....1T 2008ApJS..179....1T Cat. J/ApJS/179/1
Yencho et al. Paper II. 2009ApJ...698..380Y 2009ApJ...698..380Y
Trouille & Barger Paper IV. 2010ApJ...722..212T 2010ApJ...722..212T
(End) Emmanuelle Perret [CDS] 03-Nov-2011