5.3 Science Data

The science data will be output at a rate of 24 kbs while ACIS is at the focus of the HRMA. While the HRC is in the focus, 0.5 kbs of data will be telemetered.

There are 17 possible modes, but the most commonly used scientific mode will be the Timed Exposure, Faint Mode. In this mode, an event will be transmitted as a 9-pixel neighborhood of 12 bits/pixel to fully describe the pulse-height spectrum and allow the ground-processing system to balance the trade between resolution and quantum-efficiency. Positions are given to 18 bits. Each frame additionally contains its identification, time designation and rejected counts. Occasionally, there will be diagnostic histograms from the calibration mode.