1. Program Name: LockLoss 2. Authors: David Chin <dwchin@umich.edu> Keith Riles <kriles@umich.edu> University of Michigan 3. Purpose: Watch for acquisition and loss of lock. Based on thresholds in normalized transmitted light through the ends of the X and Y arms. 4. Outputs: A. Log and status web page Base directory: $GDSAPACHE/monitor_reports/LockLoss_XX browsable as http://server/gds/monitor_reports/LockLoss_XX where XX is one of {H1, H2, L1}, server is one of blue.ligo-wa.caltech.edu london.ligo-la.caltech.edu Let the base directory path or URL be assigned to BASEDIR. Log file: $BASEDIR/LockLoss_Log.txt Status file: $BASEDIR/LockLoss_Uptime.html B. Graphical output i) Time series data (DMTviewer) LockLoss produces several time series of data of the lock state of the interferometer. The time series also includes different values based on the value of particular sets of bits in the State Vector. These time series data are viewable using the DMTviewer. There are time series of different durations, the most useful (and most used) one being the 12 hour time series. ii) Lock segment histogram (DMTviewer) LockLoss also produces a histogram of lock stretches. Again, these are viewable using DMTviewer. iii) Trends (Data Viewer) Minute trends of the same time series data are generated, as well. Data Viewer is used to plot these in almost real time. Trend channel names are: XX:DMT-LOCKLOSS_XarmLOCK XX:DMT-LOCKLOSS_YarmLOCK XX:DMT-LOCKLOSS_BOTHarmsLOCK XX:DMT-LOCKLOSS_StateVEC The XarmLOCK, YarmLOCK, and BOTHarmsLOCK trends are self-descriptive. The StateVEC trend is a trend of the StateVector data as displayed in the Control Room. C. Alarms LockLoss generates one alarm: Lock_lost (See http://server/gds/Alarms/) D. Meta-db triggers Triggers are generated in the meta-database. The triggers are: Trigger type: "Lock transition" Trigger subtypes: i) X_arm_lock_acquired ii) X_arm_lock_lost iii) Y_arm_lock_acquired iv) Y_arm_lock_lost v) Both_arms_lock_acquired vi) Both_arms_lock_lost 5. Usage Notes: Not meant to be run stand-alone by general users. $Id: lockloss_desc.html,v 1.4 2003/09/15 00:51:07 dwchin Exp $