[ Previous | Next | ADS ]

Detection of AXP 4U 0142+614 with INTEGRAL

ATel #293; P. R. den Hartog(1), L. Kuiper(1), W. Hermsen(1, 2), J. Vink (1) (1 SRON - National Institute for Space Research, Utrecht, The Netherlands; 2 Astronomical Institute, University of Amsterdam, The Netherlands)
on 28 Jun 2004; 11:34 UT
Credential Certification: P.R. den Hartog (Hartog@sron.nl)

Subjects: X-ray, Gamma Ray, Neutron Star, Pulsar

We report the detection of the Anomalous X-ray Pulsar 4U 0142+614 at energies between 20 keV and 100 keV with IBIS/ISGRI aboard INTEGRAL. The source was detected in the field of view of the observations of the Cassiopeia region in December 2003. In the energy bands 20-50 keV and 50-100 keV it showed up with 4.8 sigma and 6.1 sigma detection significances, respectively, corresponding with 1.5 +/- 0.3 mcrab and 3.7 +/- 0.6 mcrab. This is the third AXP detected as a hard X-ray/ soft gamma-ray source with INTEGRAL. The previous two are 1E 1841-045 (Molkov et al. 2004, Bassani et al. ATEL #232) and 1RXS J170849-400910 (Revnivtsev et al. 2004). All three AXPs are unambiguously identified as AXPs by their timing signatures. Follow up timing analysis of archival RXTE-PCA and HEXTE data revealed for all three AXPs pulsed emission up to about 100 keV with similar very hard power-law spectra above 20 keV with photon indices of about 1 (for 1E 1841-045 see Kuiper et al. 2004 (APJ in press, astro-ph/0404582); for the other two sources see Kuiper et al. 2004 (A&A in prep)).

The nearby (24') source RX J0146.9+6121 is also detected by INTEGRAL in the 20-50 keV band as a 2.6 +/- 0.3 mcrab source. 4U 0142+614 and RX J0146.9+6121 are clearly resolved and therefore there is no source confusion.