<acis-fluence_P3pscaling.pl> script documentation

1. Introduction:
   acis-fluence_P3pscaling.pl is a perl script that reads in the output file produced by ace-flux.pl, ACE-flux.dat, as well as reading in the instrument focal plane and OTG history files (FPHIST-2001.txt and GRATHIST-2001.txt, respectively) produced by acis-backstop.pl. It multiplies the latest ACE/EPAM flux measurement found in ACE-flux.dat by the following "attenuation factors": 0 if the HRC is in the focal plane, 1 if ACIS is in the focal plane, 0.2 if the HETG are deployed, 0.5 if the LETG are deployed, and 1 if neither gratings are deployed. This script is run every 5 minutes via CRON so it, therefore, keeps a running sum of the "ACIS" fluence as determined by the ACE/EPAM fluxes for each orbit. Specifically, this script monitors the ACE/EPAM P3 channel. If the fluence (ie, the "running sum") in this channel exceeds 1E9, alerts are issued to various distribution lists depending upon which "version" is in violation. There are three versions currently in operation. The "primary" version, run out of /export/acis-flight/FLU-MON/ and is only visible on rhodes, sends alerts to "sot_red_alert" and "acisdude". The "back-up" versions, run out of /proj/sot/acis/FLU-MON/ and visible from any HEAD LAN machine, and out of /home/acisdude/FLU-MON on colossus sends their alerts to only "acisdude". Thus, the latter are truly "back-up" processes to make sure we are not susceptible to a single-point failure in the event of a network going down, disk crashes, etc. Moreover, this script reads in the Chandra ephemeris file located in /proj/rac/ops/ephem/gephem.dat which is produced and maintained by Tom Aldcroft. It reads this file to determine the transition from "descending" to "ascending" (via the log file cxodirect.dat) -- ie, to determine when Chandra has crossed perigee. When it has, the script resets all fluences to zero and writes the fluence for all EPAM channels to a fluence archive (ACIS-fluence.arc) file. The script also reads in the DSN schedule located in /proj/rac/ops/ephem/dsn_summary.dat which is also produced and maintained by Tom Aldcroft. If an alert is issued, the text message includes the times for next 3 DSN passes. The script keeps track of alerts spawned in an orbit by keeping a log in falert.dat. This file also gets reset at perigee. Lastly, the ACIS fluences for all the ACE/EPAM channels are output to a txt file -- ACIS-FLUENCE.dat.
2. Execution dependencies:
   Requires access to the Chandra ephemeris file located at /proj/rac/ops/ephem/gephem.dat and the DSN schedule in /proj/rac/ops/ephem/dsn_summary.dat.
3. Script dependencies:
   

   Scripts used by acis-fluence_P3pscaling.pl

   none

   Scripts that depend on the outputs

   ace-fluence.pl

   File dependancies:
   

   Input files:

   ACE-flux.dat (created by ace-flux.pl)

   FPHIST-2001.txt (created by ACE-update.ksh)

   GRATHIST-2001.txt (created by ACE-update.ksh)

   /proj/rac/ops/ephem/DSN.sch (produced and maintained by Tom Aldcroft)

   /proj/rac/ops/ephem/gephem.dat (produced and maintained by Tom Aldcroft)

   Output files:

   ACIS-FLUENCE.dat (used by ace-fluence.pl)

   ACIS-fluence.arc (used by ace-fluence.pl)

   ACE-fluence.arc (see ace-flux.pl)

   falert.dat

   cxodirect.dat

4. Code Location and execution
5. Problems and Issues
6. Notes