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MARANOXMM - Marano Field XMM-Newton X-Ray Source Optical Counterparts


This table contains some of the results from a medium deep XMM-Newton survey of the Marano Field and optical follow-up observations. The mosaicked XMM-Newton pointings in this optical quasar survey field cover 0.6 deg^2 with a total of 120 ks good observation time. 328 X-ray sources were detected in total with detection likelihoods ML >= 5. The X-ray fluxes are in the range f_X = (0.16 - 54) x 10^-14 erg cm^-2 s^-1 (0.2 - 10 keV). The turnover flux of this sample is f_X_ ~ 5 x 10^-15 erg/cm^2/s in this same energy band. With VLT FORS1 and FORS2 spectroscopy 96 new X-ray counterparts have been classified.

The central 0.28 deg^2 region, where detailed optical follow-up observations were performed, contains ~ 170 X-ray sources (detection likelihood ML > 10), out of which 48 had already been detected by ROSAT. In this region 23 out of 29 optically selected quasars have been recovered. With a total of 110 classifications in their core sample, the authors have reached a completeness of ~65%. About one-third of the XMM-Newton sources are classified as type II AGN with redshifts mostly below 1.0. Furthermore, five high redshift type II AGN (2.2 <= z <= 2.8) have been detected.

This table contains the list of the 195 optical counterparts for 172 of the XMM-Newton X-ray sources given in Table 8 of the reference paper. It does not contain the full list of 328 X-ray sources given in Table A1 of the reference paper, nor the lists of marginal X-ray sources given in Appendix B of the reference paper.

Catalog Bibcode



The XMM-Newton survey in the Marano Field.
I. The X-ray data and optical follow-up.
    Krumpe M., Lamer G., Schwope A.D., Wagner S., Zamorani G., Mignoli M.,
    Staubert R., Wisotzki L., Hasinger G
    <Astron. Astrophys. 466, 41 (2007)>
    =2007A&A...466...41K        (SIMBAD/NED BibCode)


This table was created by the HEASARC in May 2007 based on CDS catalog J/A+A/466/41 file table8.dat.


A running source number which uniquely identifies the counterpart object to the XMM-Newton X-ray source, consisting of the sequence number from the X-ray source list and a suffix (A, B) to discriminate between different optical candidates..

The name of the X-ray source optical counterpart using the '[KLS2007]' prefix (where KLS2007 refers to Krumpe, Lamer, Schwope 2007), together with the source number, in the style recommended by the CDS Dictionary of Nomenclature of Celestial Objects (although, as of May 2007, this designation had not been officially adopted by the CDS).

The Right Ascension of the optical candidate counterpart in the selected equinox. This was given in J2000.0 coordinates to a precision of 0.1 seconds of time in the original table.

The Declination of the optical candidate counterpart in the selected equinox. This was given in J2000.0 coordinates to a precision of 1 arcsecond in the original table.

The Galactic Longitude of the optical counterpart.

The Galactic Latitude of the optical counterpart.

The spatial offset between the X-ray source position and that of the optical counterpart, in arcseconds.

The SOFI K-band magnitude of the spectroscopically classified candidate, whenever available.

The WFI R-band magnitude of the spectroscopically classified candidate, whenever available.

A crude spectroscopic classification of the identified object:

    S - star,
    G - normal galaxy (no emission lines),
    N - narrow emission line galaxy with unresolved emission lines (at 6000
        Angstroms, the spectral resolution of 21 A  corresponds to 1050 km s^-1),
    B - broad emission line object (all measured line widths have FWHM} > 2500
        km s^-1), and
    ? - undefined.

The spectroscopic redshift z of the identified object. The redshift is taken from the literature for objects which have xray_id_flag values of 0 or 1, and null values of the redshift_flag and source_type_flag parameters. In such cases, the remark_flag parameter contains codes identifying the source(s) of the redshift determination and the classification.

This parameter contains the X-ray identification flag which indicates whether or not a spectroscopically classified object was accepted as the 'true' counterpart to the X-ray source. Objects which the authors consider to be the correct identification of the X-ray source are flagged by 1, while values of 0 mark objects which are not considered to be the X-ray source counterparts.

This parameter contains the redshift reliability flag, where a value of 1 means a reliable, well-established redshift determined by several spectral features, while 0 marks objects where the redshift determination relies on a single but reasonable spectral feature.

This parameter contains the classification reliability flag, where a value of 1 indicates that the object source type is well established and reliable, while a value of 0 indicates an uncertain classification of the object type: either high-SNR spectral features of the object do not allow a proper classification, or the optical spectra do not permit a reliable classification of the object type because of a low SNR and/or insufficient wavelength coverage of the optical spectra.

The observed rest-frame X-ray luminosity L_X (logarithmic units) in the 0.2 - 10 keV energy band calculated by using Eq. (1) in the reference paper [L_X = 4 pi x d_L^2 x f_X/(z + 1)^(alpha + 1)]. The k-correction vanishes since the authors assume an energy index alpha = -1 with F_nu ~ nu^alpha ~ nu^(1- Gamma), where Gamma is the photon index. The luminosity distance d_L was computed by the analytical fit for flat cosmologies with Omega_m =0.3, Omega_Lambda =0.7, and H_0 = 70 km s^-1 Mpc^-1.

The absolute Johnson B magnitude, M_B, estimated only for type I AGN, using the relation M_B = R + 5 - 5 log (d_L/pc) + K(z), where d_L is the luminosity distance and K(z) is the customary k-correction term. In this case, this term includes the transition from observed-frame R-band to rest-frame B-band, assuming a mean spectral energy distribution for all sources, and also the (1+z) bandwidth stretching factor. For the type I AGN the authors computed K(z) from the composite SDSS quasar spectrum (Vanden Berk et al. 2001, AJ, 122, 549).

The broad-band spectral index alpha _OX. This parameter roughly characterises the UV-X-ray spectral energy distribution by connecting the rest-frame points at 2500 Angstroms and 1 keV with a simple power-law, F_nu ~ nu^(-alpha_OX). Full details on the procedure for calculating alpha _OX are given in Section 3 of the reference paper.

The X-ray absorbing hydrogen column density, N_H, in units of H atoms cm^-2 (see Section 4.4 of the reference paper for more details).

The negative error in N_H, in units of H atoms cm^-2.

The positive error in N_H, in units of H atoms cm^-2.

The intrinsic rest-frame X-ray luminosity (logarithmic units) in the 0.2 - 10 keV energy band after X-ray flux correction for the absorbing hydrogen column density. The calculation uses Eq. (1) of the reference paper [L_X = 4 pi x d_L^2 x f_X/(z + 1)^(alpha + 1)].

This parameter contains codes for remarks on individual objects, as follows:

    1 - optically selected and spectroscopically classified quasar by Marano et
        al. (1988, MNRAS, 232, 111);
    2 - optically selected and spectroscopically classified quasar by Zitelli et
        al. (1992, MNRAS, 256, 349);
    3 - ROSAT X-ray source with spectroscopic classification and redshift
        determination by Zamorani et al. (1999, A&A, 346, 731);
    4 - ROSAT X-ray source with no or wrong identification by Zamorani et al.
        (1999, A&A, 346, 731);
    5 - unclassified radio objects within  5.0 arcseconds, Gruppioni et al.
        (1999, MNRAS, 304, 199);
    6 - spectroscopic classification and redshift taken from Teplitz et al.
        (2003, ApJS, 146, 209);
    7 - radio source, spectroscopic classification and redshift taken from
         Gruppioni et al. (1999, MNRAS, 304, 199).

This parameter contains a value of 'Y' if there is an individual comment about an object given in Sect. 3.1 of the reference paper (also available in the file ftp://cdsarc.u-strasbg.fr/pub/cats/J/A+A/466/41/notes.dat ).

The HEASARC Browse object classification based on the value of the source_type parameter.

Contact Person

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If you have any problems, please consult the help page or mail ledas-help@star.le.ac.uk