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 $