We present new results on the recently discovered 69 ms X-ray pulsar AXS J161730 - 505505 , the sixth youngest sample of all known pulsars .
We have undertaken a comprehensive X-ray observing campaign of AXS J161730 - 505505 with the ASCA , SAX , and XTE observatories and follow its long term spin-down history between 1989 and 1999 , using these , archival GINGA and ASCA data sets , and the radio ephemeris .
The spin-down is not simply described by a linear function as originally thought , but instead we find evidence of a giant glitch ( | \Delta P / P| \stackrel { > } { { } _ { \sim } } 10 ^ { -6 } ) between 1993 August and 1997 September , perhaps the largest yet observed from a young pulsar .
The glitch is well described by steps in P and { \dot { P } } accompanied by a persistent { \ddot { P } } similar to those in the Vela pulsar .
The pulse profile of AXS J161730 - 505505 presents a single asymmetric peak which is maintained over all observation epochs .
The energy spectrum is also steady over time , characterized by a highly absorbed power-law with a photon index \Gamma = 1.4 \pm 0.2 , consistent with that found for other young rotation powered pulsars .