IGR J20187+4041

Other name = IGR J20186+4043, 2MASX J20183871+4041003, 3EG J2020+4017 (?), GeV J2020+4023 (?)

Type Redshift Radio Counterpart Infrared/Optical Counterpart
R.A. (J2000) Dec. (J2000) References R.A. (J2000) Dec. (J2000) References
AGN, Sey 2(?) z = 0.0144 20h 18m 38.7374s (±2e-3 arcsec) +40o 40' 59.984" (±2e-3 arcsec) Trejo et al. 2008 ATel 1597 20h 18m 38.73s +40o 41' 00.1"
Miscellaneous :

Kennea et al. 2006: ATel 788
  • Absorbed powerlaw fit to Swift data yields Gamma = 0.7(+2.2,-0.2) and NH = 4(+6/-3)x1022 cm-2.
  • Possible NIR counterpart in 2MASS catalog is only 2.6 arcseconds away with magnitudes J=14.9, H=12.7, Ks=12.1.
Bykov et al. 2006:
  • Absorbed powerlaw fit to Swift/ISGRI data yields Gamma = 1.3(+-0.2) and NH = 6.1x1022 cm-2.
  • J=13.0, H=11.5, Ks=10.7, Red=18.1, Blue>22.5
  • Possible extended radio counterparty but association not so clear
  • Couterpart to 3EG J2020+4023
Ajello et al. 2008: Atel 1497
  • IGR J20187+4041 positionnaly coincident with recently detected variable AGILE source, and also BAT source.
  • XRT-BAT spectra well fitted with absorbed power-law NH=12.4x1022 cm-2, and Γ=1.6(±0.2).
  • Jan. 2005-Mar. 2007 BAT lightcurve consistent with constant
Halpern 2008: Atel 1498
  • 2MASX J20183871+4041003 outside the EGRET error box
  • 2MASX source has blazar-like characteristics not based on any physical property of the galaxy (as e.g. the absence of a compact radio source).
  • Relationship of the AGILE source to 2MASX J20183871+4041003 is problematic for similar reasons.
  • I-band image of 2MASX J20183871+4041003 from the MDM 2.4m telescope=> bulge and disk are clearly resolved
  • Nearby (z<0.1) Seyfert galaxy
  • Contrast with the fact that blazars are normally found in elliptical galaxies.
Pandel et al. 2008: Atel 1595
  • XMM observations=> spectrum well fitted by an absorbed power law with NH=8 x1022 cm-2 and Γ=1.2
  • 0.5-10 keV flux =4.3 x10-12 erg/cm2/s.
  • Flux and spectral parameters are consistent with Swift observation performed in 2006=>no variability between those two observations.
Trejo et al. 2008: Atel 1597
  • E-VLBI observations of 2MASX J20183871+4041003 => peak brightness of 0.72 +/- 0.05 mJy and an integrated flux density of 2.3 +/- 0.2 mJy.
  • Presence of a compact radio component => eligible candidate for being the counterpart to the variable gamma source in the Cygnus region
  • Low density of the flux does not suggest recent flaring activity in the source.
Goncalves et al. 2008: Atel 1623
  • Spectroscopic observations of 2MASX J20183871+4041003
  • They report the detection of narrow emission lines of Hα, N II, a doublet S II, and S III, stellar photospheric absorption in Ca II (3 lines)
  • z = 0.0144
  • Near-IR continuum dominated by starlight.
  • Low luminosity Sey. Tentative classification as a Sey 2.
  • Refute the association with EG J2020+4017 or AGL2021+4029.

Last updated. 30 Nov 2011

Jerome Rodriguez