GCN Circular 10534
Ersin Gogus (Sabanci Univ), Tod Strohmayer (NASA/GSFC), Chryssa Kouveliotou (NASA/MSFC), Peter Woods (Dynetics) Discovery of the Spin Period of SGR 1833-0832 Following the Swift detection of a burst from the new Soft Gamma Repeater SGR 1833-0832 (Gelbord, J. et al. 2010, GCN #10526) we triggered our SGR ToO Program with RXTE. A 1.3 ks RXTE observation started on 2010 March 19, 21:49:52UT. We detect coherent pulsations from the new SGR in the 2-20 keV PCA data at 0.1321 Hz, corresponding to a spin period of 7.57 sec. We then performed timing analysis on 22.5 ks Swift/XRT data in PC mode and confirmed the period detection as 7.5654(1) s. We note that there is no previously known X-ray source in the RXTE field of view with such periodicity. The detected coherent pulsations likely indicate the spin period of the newly discovered, burst-active SGR. We thank the RXTE planner, Divya Pereira for the prompt scheduling of the RXTE observations and Scott Barthelmy, Jonathan Gelbord and Neil Gehrels from the Swift team for valuable and prompt information exchange on this new source.