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arXiv · 0907.4348

A Possible Period for the K-band Brightening Episodes of GX 17+2

Jillian Bornak·Bernard J McNamara·Thomas E Harrison·Michael P Rupen·Reba M Bandyopadhyay·Stefanie Wachter
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Abstract

The low mass X-ray binary and Z source GX 17+2 undergoes infrared K-band brightening episodes of at least 3.5 magnitudes. The source of these episodes is not known. Prior published K-band magnitudes and new K-band measurements acquired between 2006 and 2008 suggest that the episodes last at least 4 hours and have a period of 3.01254 $\pm$ 0.00002 days. Future bright episodes can be predicted using the ephemeris JD_{max} (n) = 2454550.79829 + (3.01254 $\pm$ 0.00002)(n) days. A growing body of evidence suggests that the GX 17+2 could have a synchrotron jet, which could cause this activity.

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Jillian Bornak, Bernard J McNamara, Thomas E Harrison, Michael P Rupen, Reba M Bandyopadhyay, Stefanie Wachter. 2009-07-24. A Possible Period for the K-band Brightening Episodes of GX 17+2. https://doi.org/10.1088/0004-637x%2F701%2F2%2Fl110

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