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J/A+A/490/879       XMM-LSS field optical identifications    (Tasse+, 2008)

Radio-loud AGN in the XMM-LSS field. I. Optical identification and sample selection. Tasse C., Le Borgne D., Roettgering H., Best P.N., Pierre M., Rocca-Volmerange B. <Astron. Astrophys., 490, 879-891 (2008)> =2008A&A...490..879T
ADC_Keywords: Radio sources ; Cross identifications ; Photometry, SDSS ; Photometry, millimetric/submm Keywords: methods: observational - techniques: photometric - galaxies: active - galaxies: fundamental parameters - cosmology: observations - radio continuum: galaxies Abstract: The XMM-Large Scale Structure survey field (XMM-LSS) is an extragalactic window surveyed in the X-ray with the XMM-Newton satellite. It has also been observed in the optical with the Canada-France Hawaii Telescope (CFHTLS survey), and in the infrared with the Spitzer Space Telescope (SWIRE survey). These surveys have been carried out to study the structure and evolution of both baryonic and dark matter on cosmological scales. In two previous papers, we presented deep low frequency radio surveys of the XMM-LSS field, with limiting flux density levels of ∼4 and ∼1.5mJy/beam at 325 and 610MHz respectively (5σ). These radio surveys were motivated by the need to understand the various connections between the host galaxies of radio sources and their environments. In this paper, we identify optical counterparts to the low frequency radio sources, using the CFHTLS optical catalogue and images, that have an i-band limiting magnitude of iAB∼25. Description: We use the radio data described in detail in Tasse et al. (2006, Cat. J/A+A/456/791). The observations were carried out using the Very Large Array (VLA) at 74 and 325MHz simultaneously (4P mode). The radio survey consists of four pointings, observed in June, July and August 2003 in the A configuration and in June and July 2002 in the B configuration Low-frequency radio observations of the XMM-LSS have been carried out with the Giant Meterwave Radio Telescope (GMRT) at 230 and 610MHz (Tasse et al., 2007, Cat. J/A+A/471/1105). These data provide two additional flux density measurements for 41% of the radio sources detected at 325MHz with the VLA. Observations with the CFHTLS-W1 were carried out between June 1, 2003 and Sept. 12, 2005. Throughout this paper we have used the SWIRE data release 2 band-merged catalog available online (, containing the flux density measurements at 3.6, 4.5, 5.8, 8.0 and 24um for a total of ∼2.5x105 objects. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tabled2.dat 164 761 Sample and optical identification table1.dat 14 25 The distribution of the original SWIRE template name (Polletta et al. 2007, Cat. J/ApJ/663/81) through our classification (see Sect. 4.2)
See also: J/A+A/456/791 : XMM-LSS field at 74 and 325MHz (Tasse+, 2006) J/A+A/471/1105 : XMM-LSS at 240MHz and 610MHz (Tasse+, 2007) Byte-by-byte Description of file: tabled2.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Name Radio source name (JHHMM.m+DDMM), [TLR2008] Rad JHHMM.m+DDMMa in Simbad 13 A1 --- m_Name [ab] Multiplicity index on Name 14- 15 A2 --- n_Name [* ] Note on Name (1) 17 I1 --- Cl [1,5] Radio source class (7) 19- 20 I2 h RAh ?=- Optical counterpart right ascension (J2000) 22- 23 I2 min RAm ?=- Optical counterpart right ascension (J2000) 25- 29 F5.2 s RAs ?=- Optical counterpart right ascension (J2000) 31 A1 --- DE- Optical counterpart declination sign (J2000) 32- 33 I2 deg DEd ?=- Optical counterpart declination (J2000) 35- 36 I2 arcmin DEm ?=- Optical counterpart declination (J2000) 38- 42 F5.2 arcsec DEs ?=- Optical counterpart declination (J2000) 44 A1 --- l_umag Limit flag on umag 45- 49 F5.2 mag umag ? u-band magnitude 50 A1 --- n_umag [N] N : field not observed in that band 52 A1 --- l_gmag Limit flag on gmag 53- 57 F5.2 mag gmag ? g-band magnitude 58 A1 --- n_gmag [N] N : field not observed in that band 60 A1 --- l_rmag Limit flag on rmag 61- 65 F5.2 mag rmag ? r-band magnitude 66 A1 --- n_rmag [N] N : field not observed in that band 68 A1 --- l_imag Limit flag on imag 69- 73 F5.2 mag imag ? i-band magnitude 74 A1 --- n_imag [N] N : field not observed in that band 76 A1 --- l_zmag Limit flag on zmag 77- 81 F5.2 mag zmag ? z-band magnitude 82 A1 --- n_zmag [N] N : field not observed in that band 84 I1 --- f1 ? Flag = star+2*mask+4*sat (2) 86- 90 F5.1 % Pr ? Probability of identification (3) 92 A1 --- l_3.6mag Limit flag on 3.6um 93- 97 F5.2 mag 3.6mag ? 3.6um magnitude (AB) 98 A1 --- n_3.6mag [N] N standing for "Not Covered" (4) 100 A1 --- l_4.5mag Limit flag on 4.5um 101-105 F5.2 mag 4.5mag ? 4.5um magnitude (AB) 106 A1 --- n_4.5mag [N] N standing for "Not Covered" (4) 108 A1 --- l_5.8mag Limit flag on 5.8um 109-113 F5.2 mag 5.8mag ? 5.8um magnitude (AB) 114 A1 --- n_5.8mag [N] N standing for "Not Covered" (4) 116 A1 --- l_8.0mag Limit flag on 8.0um 117-121 F5.2 mag 8.0mag ? 8.0um magnitude (AB) 122 A1 --- n_8.0mag [N] N standing for "Not Covered" (4) 124-125 I2 --- SpT ? Spectral type of the best fit SWIRE template (see table1.dat) 126 A1 --- f_SpT [NF] Spectral type not fitted (5) 128-132 F5.1 % PT1 ? Probability of the true underlying SED object to be of contamining type-1 AGN 133 A1 --- f_PT1 [NF] SED not fitted (5) 135-138 F4.2 --- z ? Photometric redshift as estimated by ZPEG 140-144 F5.2 [solMass] logMass ? Stellar mass as estimated by ZPEG (log scale) 146-151 F6.2 [yr-1] logSFR ? Specific SFR0.5 averaged over 0.5Gyr as estimated by ZPEG (log scale) 152-153 A2 --- n_logSFR [-i ] -i for logSFR=-∞ 155-160 F6.2 % P' ? Probability of association corrected for misidentification (see Sect. 3.5) 161 A1 --- n_P' [*] Note on P' (when 100%) 163-164 I2 --- f2 ? Flag = S2+2*C+4*T1+8*SB (6)
Note (1): Notes as follows: * = the source is detected at 610MHz, but not at 325MHz (Fig. E1). In such cases, the radio contours overlaid with the optical images are presented in Fig. E2. ** = the radio contours overlaid with the optical images are presented in Fig. E3, because the source is classified as class 4. Note (2): Flag = star+2*mask+4*sat, where defaults parameters are 0: star = 1 if the optical object is point-like, mask = 1 if the object is in a masked region, and sat = 1 if the objects is saturated. Note (3): When a source has its likelihood ratio above the chosen LRcut, that value indicates the probability of identification that has been computed using the information on the i-band magnitude only (see Sect. 3.2). Note (4): Used when the location of the object does not overlap with the SWIRE field. Note (5): F = fitting procedure failed (see discussion in Sect. 4.2) N = Not analysed Note (6): Flag = S2+2*C+4*T1+8*SB, where S2 = 1 if the object belong to the S2 sample, C = 1 if the object satisfies the selection criteria of Sect. 5, T1 = 1 if the object is flagged as being type-1 AGN (Sect. 5.1), and SB = 1 if the radio luminosity of the object has a significant contribution from a starburst (Sect. 5.2). Note (7): Classes detailed in Appendix 1; a summary is: 1 = radio emission is assumed to be produced at the physical location of optical emission (detected or not), e.g. starbursts 2 = no radio core identified 3 = the environment has a large effect on the radio morphology (the radio centroid can be very far from the optical host) 4 = radio sources for which the morphology does not suggest the presence of jets, e.g. radio halos and relics. 5 = the radio source overlaps a bright saturated source (no identification is possible)
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 4 A4 --- Type Type (N/T2 or T1) (1) 6- 7 I2 --- SpT Spectral type code 9- 14 A6 --- Def Type of galaxy for the SpT code
Note (1): Type as follows: N/T2 = Normal/Type-2, for the SEDs in which there is either no contribution, or moderate contribution from an AGN T1 = Type-1, for templates with strong AGN contribution such as the QSOs
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 18-Mar-2010
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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