Swift/XMM-Newton refined timing solution for SGR0501+4516

The Swift satellite observed SGR 0501+4516 several times during the last two weeks (ATEL #1676, #1677, #1678, #1682, #1683), and XMM-Newton observed the source on August 23rd (ATEL #1688). By merging the two datasets we were able to obtain a phase-coherent timing solution. According to our analysis the preliminary period and period derivative of SGR 0501+4516 are P = 5.7620699(4) s and Pdot = 5(1) x 10<SUP>-12</SUP> s/s (1 sigma uncertainties).