J/A+A/656/A117 Chandra J1030 Redshift identification (Marchesi+, 2021)
Redshift identification of X-ray selected active galactic nuclei in the J1030
field: searching for large-scale structures and high-redshift sources.
Marchesi S., Mignoli M., Gilli R., Peca A., Bolzonella M., Nanni R.,
Annunziatella M., Balmaverde B., Brusa M., Calura F., Cassara L.P.,
Chiaberge M., Comastri A., Cusano F., D'Amato Q., Iwasawa K., Lanzuisi G.,
Marchesini D., Morishita T., Prandoni I., Rossi A., Tozzi P., Vignali C.,
Vito F., Zamorani G., Norman C.
<Astron. Astrophys. 656, A117 (2021)>
=2021A&A...656A.117M 2021A&A...656A.117M (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Active gal. nuclei ; X-ray sources
Keywords: galaxies: Seyfert - large-scale structure of Universe -
galaxies: high-redshift - quasars: supermassive black holes -
X-rays: galaxies
Abstract:
We publicly release the spectroscopic and photometric redshift catalog
of the sources detected with Chandra in the field of the z=6.3 quasar
SDSS J1030+0525. This is currently the fifth deepest X-ray field, and
reaches a 0.5-2keV flux limit f0.5-2=6x10-17erg/s/cm2. By using
two independent methods, we measure a photometric redshift for 243
objects, while 123 (51%) sources also have a spectroscopic redshift,
110 of which coming from an INAF-Large Binocular Telescope (LBT)
Strategic Program. We use the spectroscopic redshifts to determine the
quality of the photometric ones, and find it in agreement with that of
other X-ray surveys which used a similar number of photometric
data-points. In particular, we measure a sample normalized median
absolute deviation
sigmaNMAD=1.48xmedia(||zphot-zspec||/(1+zspec)=0.065.
We use these new spectroscopic and photometric redshifts to study the
properties of the Chandra J1030 field. We observe several peaks in our
spectroscopic redshift distribution between z=0.15 and z=1.5, and find
that the sources in each peak are often distributed across the whole
Chandra field of view. This evidence confirms that X-ray selected AGN
can efficiently track large-scale structures over physical scales of
several Mpc. Finally, we computed the Chandra J1030 z>3 number counts:
while the spectroscopic completeness at high-redshift of our sample is
limited, our results point towards a potential source excess at z≥4,
which we plan to either confirm or reject in the near future with
dedicated spectroscopic campaigns.
Description:
We present the spectroscopic and photometric redshift catalog for the
Chandra J1030 survey, the fifth-deepest Xray survey currently
available.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 256 256 Chandra J1030 multi-wavelength catalog
splist.dat 23 149 List of fits spectra
sp/* . 149 Individual spectra in fits
sedmod/* . 243 Best-fit model
sedsrc/* . 243 Photometric points
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See also:
J/A+A/637/A52 : Deep Chandra survey in J1030+0524 field (Nanni+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 A1 --- SED [*] * for sources with SED
3- 5 I03 --- XID Chandra J1030 ID (from Nanni et al.,
2020A&A...637A..52N 2020A&A...637A..52N, Cat. J/A+A/637/A52)
(XID)
7- 8 I2 h RAh Right Ascension, X-ray source (J2000)
(RACORRX)
10- 11 I2 min RAm Right Ascension, X-ray source (J2000)
(RACORRX)
13- 17 F5.2 s RAs Right Ascension, X-ray source (J2000)
(RACORRX)
19 A1 --- DE- Declination sign, X-ray source (J2000)
(DECCORRX)
20- 21 I2 deg DEd Declination, X-ray source (J2000)
(DECCORRX)
23- 24 I2 arcmin DEm Declination, X-ray source (J2000)
(DECCORRX)
26- 30 F5.2 arcsec DEs Declination, X-ray source (J2000)
(DECCORRX)
32- 38 A7 --- ID-LBT ID from the z-detected LBC catalog
(Morselli et al., 2014A&A...568A...1M 2014A&A...568A...1M)
(ID_LBT) (1)
40- 41 I2 h RAOh Right Ascension, optical/IR counterpart
(J2000) (RA_cpt)
43- 44 I2 min RAOm Right Ascension, optical/IR counterpart
(J2000) (RA_cpt)
46- 50 F5.2 s RAOs Right Ascension, optical/IR counterpart
(J2000) (RA_cpt)
52 A1 --- DEO- Declination sign, optical/IR counterpart
(J2000) (RA_cpt)
53- 54 I2 deg DEOd Declination, optical/IR counterpart (J2000)
(RA_cpt)
56- 57 I2 arcmin DEOm Declination, optical/IR counterpart (J2000)
(RA_cpt)
59- 63 F5.2 arcsec DEOs Declination, optical/IR counterpart (J2000)
(RA_cpt)
65- 69 F5.2 mag rmag r-band AUTO magnitude [AB] (mag_r)
71- 75 F5.2 mag zmag z-band AUTO magnitude [AB] (mag_z)
77- 81 F5.2 mag Jmag J-band AUTO magnitude [AB] (mag_J)
83- 87 F5.2 mag [4.5um] IRAC 4.5 micron AUTO magnitude [AB]
(magIRACCH2)
89- 97 F9.5 --- zbest ?=-99 Source redshift: spectroscopic when
available, photometric otherwise (z_best)
99-107 F9.5 --- zspec ?=-99 Source spectroscopic redshift
(z_spec) (2)
109-113 F5.1 --- specFlag [0/2]?=-99 Spectrum flag (spec_flag) (3)
115-125 A11 --- specType ?=-99 Spectral type (spec_type)
127-130 A4 --- specInst Spectral origin (spec_instrument) (4)
132-138 F7.3 --- zphotbest ?=0 Photometric redshift (zphotbest)
140-145 F6.2 --- b_zphotbest ?=0 Photometric redshift 68% lower boundary
(from the PDZ) (zphotPdz68_lo)
147-152 F6.2 --- B_zphotbest ?=0 Photometric redshift 68% upper boundary
(from the PDZ) (zphotpdz68_up)
154-160 F7.3 --- chiphot ?=0 Reduced chi square of the photometric
redshift SED fit (chi_phot)
162-167 A6 --- SEDtemp SED template type (SED_template)
169-173 A5 --- Morph Source morphology (Morphology)
175-176 I2 --- Nband Number of bands in which the source is
detected (N_band)
178-184 F7.3 --- F0.5-2 0.5-2keV band flux (Flux_05-2)
186-192 F7.3 --- F2-7 2-7keV band flux (Flux_2-7)
194-199 F6.3 --- HR Hardness ratio (from Nanni et al., 2020,
Cat. J/A+A/637/A52) (HR)
201-206 F6.3 --- b_HR Hardness ratio lower boundary (from Nanni
et al. 2020, Cat. Cat. J/A+A/637/A52)
(HR_lo)
208-213 F6.3 --- B_HR Hardness ratio upper boundary (from Nanni
et al. 2020, Cat. Cat. J/A+A/637/A52)
(HR_up)
215-220 F6.2 --- logNH ?=0 Hydrogen column density (logNH)
222-227 F6.2 --- b_logNH ?=0 Hydrogen column density lower boundary
(logNH_lo)
229-234 F6.2 --- B_logNH ?=0 Hydrogen column density upper boundary
(logNH_up)
236-242 F7.3 --- LXdeabs0.5-2 ?=0 Logarithm of the rest-frame,
absorption-corrected 0.5-2keV luminosity
(Lxdeabs05-2)
244-250 F7.3 --- Lxdeabs2-7 ?=0 Logarithm of the rest-frame,
absorption-corrected 2-7 keV luminosity
(Lxdeabs2-7)
252-253 I2 --- FlagdetS ?=-1 "1": Source detected in the 0.5-2keV
band in Nanni et al. (2020,
Cat. J/A+A/637/A52) (FlagdetS)
255-256 I2 --- FlagdetH ?=-1 "1": Source detected in the 2-7keV
band in Nanni et al. (2020,
Cat. J/A+A/637/A52) (FlagdetH)
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Note (1): Sources detected in the r-deep catalog only are flagged with a r,
and sources detected only in the IRAC band are identified as "IRAC NNN",
where NNN is a numerical ID.
Note (2): Sources with a spectrum lacking clearly identifiable features are
flagged with -9.99;
sources with no detection in a slit are flagged with -8.88; and
sources for which no spectroscopic observations were performed are
flagged with -99.
Note (3): Spectral quality flag as follows:
0.0 = Sources without zspec
1.0 = Sources with uncertain redshift
2.0 = Sources with secure redshift
Note (4): Spectral origin as follows:
D = DEIMOS on Keck II
F = FORS2 on VLT
L = LUCI on LBT
M = MODS on LBT
Mu = MUSE on VLT
S = SDSS
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Byte-by-byte Description of file: splist.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- XID Chandra J1030 ID (from Nanni et al.,
2020A&A...637A..52N 2020A&A...637A..52N, Cat. J/A+A/637/A52)
5- 23 A19 --- FileName Name of the spectrum fits file
in subdirectory sp
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Byte-by-byte Description of file (#): sedmod/*
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 E7.6 0.1nm lambda Wavelength
14- 19 E6.4 mag mag Model magnitude (AB)
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Byte-by-byte Description of file (#): sedsrc/*
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Bytes Format Units Label Explanations
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1- 7 E7.6 0.1nm lambda Wavelength
14- 20 E7.5 mag mag Source magnitude (AB)
21- 27 E7.5 mag e_mag ?=-1 rms uncertainty on mag
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Acknowledgements:
Stefano Marchesi, stefano.marchesi(at)inaf.it
(End) Patricia Vannier [CDS] 18-Nov-2021