INTIBISAG2 - INTEGRAL IBIS AGN Catalog Update

Overview

In the most recent IBIS survey based on observations performed during the first 1000 orbits of INTEGRAL, there are listed 363 high-energy emitters firmly associated with AGN, 107 of which are reported here for the first time. The authors have used X-ray data to image the IBIS 90% error circle of all the AGN in the sample of 107, in order to obtain the correct X-ray counterparts, locate them with arcsecond accuracy and therefore pinpoint the correct optical counterparts. This procedure has led to the optical and spectral characterization of the entire sample. This new set consists of 34 broad line or type 1 AGN, 47 narrow line or type 2 AGN, 18 blazars and 8 sources of unknown class. These eight sources have been associated with AGN from their positional coincidence with 2MASX/Radio/X-ray sources. Seven high-energy emitters have also been included since they are considered to be good AGN candidates. Spectral analysis has been already performed on 55 objects and the results from the most recent and/or best statistical measurements have been collected. For the remaining 52 sources, the authors report the spectral analysis for the first time in this work. They have been able to obtain full X-ray coverage of the sample making use of data from Swift/XRT, XMM-Newton and NuSTAR. In addition to the spectral characterization of the entire sample, this analysis has enabled the authors to identify peculiar sources and by comparing different data sets, highlight flux variability in the 2-10 keV and 20-40 keV bands.

In the reference paper, the authors present the X-ray and optical follow-up work on 107 new AGN recently detected by INTEGRAL. Fortunately, they have been able to obtain full X-ray coverage of the entire sample making use of data from the Swift/XRT, Newton-XMM, and NuSTAR archives or through Swift/XRT follow-up observations that they triggered.

The HEASARC notes that this table of AGN newly detected by INTEGRAL and not included in the original INTEGRAL IBIS AGN Catalog (Malizia et al. 2012, MNRAS, 426, 1750, available at the HEASARC as the INTIBISAGN table) actually contains 108 AGN plus 8 candidate AGN, for a total of 116 objects, rather than the 107 plus 7 candidate AGN totalling 114 objects that are quoted in the abstract of the reference paper (and stated above). The reason for this discrepancy is not known to the HEASARC.

Catalog Bibcode

2016MNRAS.460...19M

References

The INTEGRAL/IBIS AGN catalogue: an update.
    Malizia A., Landi R., Molina M., Bassani L., Bazzano A., Bird A.J.,
    Ubertini P.
   <Mon. Not. R. Astron. Soc., 460, 19-29 (2016)>
   =2016MNRAS.460...19M    (SIMBAD/NED BibCode)
The INTEGRAL/IBIS AGN catalogue.
I. X-ray absorption properties versus optical classification.
    Malizia A., Bassani L., Bazzano A., Bird A.J., Masetti N., Panessa F.,
    Stephen J.B., Ubertini P.
   <Mon. Not. R. Astron. Soc., 426, 1750-1766 (2012)>
   =2012MNRAS.426.1750M

Provenance

This table was created by the HEASARC in November 2017 based on CDS Catalog J/MNRAS/460/19 files tablea1.dat and refs.dat.

Parameters

Candidate_Flag
This flag parameter is set to 'c' to indicate that the object is an AGN candidate and not a confirmed AGN.

Name
A commonly used name for the AGN or candidate AGN.

Source_Flags
This flag parameter can contain notes about the source, coded as follows:

     f = the source was already present in previous IBIS catalogs but was only
          recently identified as an AGN, and hence it is reported here as a new
          INTEGRAL AGN;
     i = there are 2 X-ray sources, 1 identified as a Sy 1.2 and 1 an AGN
          candidate, present in the IBIS error box.

Alt_Name
An alternative name for the source present in previous catalogs.

RA
The Right Ascension of the source in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.1 seconds of time in the original table.

Dec
The Declination of the source in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 1 arcsecond in the original table.

LII
The Galactic Longitude of the source.

BII
The Galactic Latitude of the source.

Redshift
The redshift of the source.

Source_Type
The classification of the AGN using the following types for confirmed examples: AGN, BL Lac, Cluster/blazar, LINER, QSO/Blazar, RG (for radio galaxy), Sy 1, Sy1.2, Sy1.5, Sy1.8, Sy1.9 and Sy2, and 'cand' for candidate AGN.

Source_Type_Flags
This flag parameter can contain notes about the source, coded as follows:

     e = new classification from Masetti et al. (in preparation);
     h = the blazar object is blended with a CV but Bassani et al.
          (2014, A&A, 561, A108) have estimated that 90% of the hard X-ray
          flux comes from the AGN.

Data_Source
The satellite or instrument used to acquire the X-ray data for the 55 sources already known in the literature.

Exposure
The exposure time, in seconds, for sources whose X-ray data were analyzed in this work, i.e., in the reference paper. The satellite or instrument used is specified in the exposure_flag parameter.

Exposure_Flag
This parameter indicates which satellite or instrument was used for those sources whose soft X-ray data were analyzed as part of the present study, i.e., those entries in which the length of the exposure is specified (in the exposure parameter), coded as follows:

  (blank) = Swift/XRT data
        d = XMM data
        g = NuSTAR data

XRT_Significance
The significance of the XRT source detection in the 0.3-10 keV band, i.e., the number of sigma, for those sources whose X-ray data were analyzed in this work, i.e., in the reference paper.

NH_Limit
This limit flag is set to '<' if the quoted intrinsic column density is an upper limit, else is blank.

NH
The measured intrinsic column density towards the AGN, in units of H atoms cm^-2.

NH_Pos_Err
The upper error in the intrinsic column density towards the AGN, in units of H atoms cm^-2.

NH_Neg_Err
The lower error in the intrinsic column density towards the AGN, in units of H atoms cm^-2.

Photon_Index
The power-law photon index (Gamma) of the XRT spectrum of the source in the best energy range depending on the detection significance of the source.

Photon_Index_Pos_Err
The upper error in the power-law photon index (Gamma) of the XRT spectrum of the source.

Photon_Index_Neg_Err
The lower error in the power-law photon index (Gamma) of the XRT spectrum of the source.

Photon_Index_Flag
This flag parameter is set to 'f' to indicates that the value of the photon index (Gamma) was fixed rather than fitted. The authors did not always have sufficient statistics to investigate the spectral behavior in the 2-10 keV energy range in depth. Therefore, in order to characterize the X-ray spectra they employed a simple power-law model absorbed by the Galactic column density and, if required, by intrinsic absorption. In a number of cases (11 sources) it was necessary to fix the photon index at the canonical value of Gamma = 1.7 in order to estimate the absorption and the 2-10 keV flux.

SB_Flux
The soft-band (2-10 keV) flux of the source, in erg s^-1 cm^-2.

SB_Flux_Max
The upper value of the soft-band (2-10 keV) flux of the source, in erg s^-1 cm^-2, if the source was found to be significantly variable in this band (indicated by a value of the sb_flux_flag parameter of '(var)'.

SB_Flux_Flag
If the source was found to be significantly variable in this band, this parameter is set to '(var)'.

HB_Flux_Limit
This limit flag is set to '<' if the quoted hard-band flux is an upper limit, else is blank.

HB_Flux
The hard-band (20-100 keV) flux of the source measured by INTEGRAL/IBIS, in erg s^-1 cm^-2.

Ref_Bibcode
The bibliographic code ('bibcode') of the reference from which the quoted soft X-ray information on the source was taken.

Ref_Authors
The authors of the reference from which the quoted soft X-ray information on the source was taken.

Ref_Comments
Some comments regarding the reference from which the quoted soft X-ray information on the source was taken.

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

Contact Person

Questions regarding the INTIBISAG2 database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:29:13 EDT