A \sim 50 ks XMM-Newton observation of SGR 1900 + 14 has been carried out in September 2005 , after almost three years 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 \Gamma =1.9 \pm 0.1 , temperature kT=0.47 \pm 0.02 keV and N _ { H } = ( 2.12 \pm 0.08 ) \times 10 ^ { 22 } cm ^ { -2 } , similar to previous observations of this source .
The flux was \sim 5 \times 10 ^ { -12 } erg cm ^ { -2 } s ^ { -1 } , 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 April 2006 showed a flux \sim 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 \sigma ) , depending on the assumed line energy and width , on the equivalent width of lines in the 1-9 keV range .