GCN Circular 1438
V. M. Kaspi (McGill University/Massachusetts Institute of Technology), J. Jensen (Gemini), F. Rigaut (Gemini), A. Hatakeyama (Gemini), P. M. Woods (USRA/NSSTC) report Gemini North 8-m near-IR observations of the anomalous X-ray pulsar 1E 2259+586 field. K_s band data were obtained on June 21, 2002 at 14:44 UT using the NIRI instrument and a 30-min exposure with seeing 0.7". The reported possible IR counterpart to the pulsar (Hulleman et al. 2000, A&A, 358, 605) was detected with preliminary magnitude 20.36 +/- 0.15, 1.34 mag brighter than the quiescent value, indicating the source was 3.4 times brighter (5.4 sigma c.l.) 3 days following the SGR-like X-ray bursts detected with RXTE/PCA (IAUC 7924). This confirms the IR identification. Further IR/optical monitoring is advised. A preliminary Gemini/NIRI image can be found at http://www.physics.mcgill.ca/~vkaspi/1E2259+586/Gemini.html Note that the relative brightnesses of the pulsar counterpart and star 3 in the Hulleman et al. K_s Keck image are reversed in the Gemini image, demonstrating that the pulsar brightened.