ACS Status

Linda Smith,, and David Golimowski,

The Wide Field Channel (WFC) of the Advanced Camera for Surveys (ACS) is continuing to perform well, but the Solar Blind Channel (SBC) is currently suspended. After an electronic upset in Hubble’s Science Instrument Control and Data Handling Unit (SI C&DH) in September 2010, we learned that we cannot turn off the high-voltage power supply of the SBC during such an event.  Under certain circumstances, such a failure could result in damage to the Multi-Anode Micro-channel Array detector.  Consequently, we have suspended all SBC observations until the installation of corrective updates to the flight software. We expect SBC science operations to resume toward the end of March 2011.

The ACS team has recently released two software items to mitigate the effects of charge transfer inefficiency (CTI) and the faint horizontal bias stripes seen in post-SM4 data. (See accompanying articles by J. Anderson and N. Grogin.) The software forms part of the Space Telescope Science Data Analysis System release in January 2011; downloads are also available from the ACS software web page.  The ACS team is working to incorporate the pixel-level CTI correction code in the ACS data-reduction pipeline, CALACS. We welcome any comments that users may have on these software tasks.