Operating Modes

The OXS will normally be operated in conjunction with the LEPC. During observations with the OXS, the source will be located $\sim90^{\circ}$from the pointing direction of the telescope. To ensure coverage of the full angular extent of diffuse sources over the range of Bragg angles of interest, the telescope will be repositioned several times during the observation. Current expectations are that a typical OXS observation will consist of $\sim10$ successive pointings, separated by $\mathrel{\copy\simlessbox}10^{\prime}$, each of 10⁴ seconds duration. For observations of point sources, both the telescope pointing direction and the angle between the crystal panel and telescope will be adjusted to keep the source on-axis for the entire observation.