SIMBAD references

A ∼50 ks XMM-Newton observation of SGR 1900+14 has been carried out in 2005 September, after almost 3 yr during which no bursts were detected from this soft gamma-ray repeater. The 0.8-10 keV spectrum was well fit by a power law plus blackbody model with photon index Γ=1.9±0.1, temperature kT=0.47±0.02 keV, and N_H=(2.12±0.08)x10²²/cm2, similar to previous observations of this source. The flux was ∼5x10^–12 ergs/cm2/s, a factor 2 dimmer than the typical value and the smallest ever seen from SGR 1900+14. The long-term fading of the persistent emission has been interrupted by the recent burst reactivation of the source. A Target of Opportunity XMM-Newton observation performed in 2006 April showed a flux ∼15% higher. This variation was not accompanied by significant changes in the spectrum, pulsed fraction, and light-curve profile. We searched for emission and absorption lines in the spectra of the two observations, with negative results and setting tight upper limits of 50-200 eV (3 σ), depending on the assumed line energy and width, on the equivalent width of lines in the 1-9 keV range.