Minutes of INDRA Monitoring Discussion
Purpose of Meeting
Discussion of requirements, not of the implementation details.
- To survey, as a function of time, the state of the different parameters
of the INDRA detector and to fill a time oriented data-base.
- To fill a run number oriented data base reflecting this state. This
data base would serve for the making of the data Summary Tapes and will
also allow for a reliable estimate of the data reduction tasks.
- To allow alarming and trending functions during the detector
preparation and the data taking.
- The links between, or the separation of, these two data bases is an open
question.
The INDRA parameters to be monitored are (the number of parameters are in
parenthesis):
- 1. General:
- SIS setup, Target, Comments, ect.
- 2. J. Ropert's slow control system:
- Preasures, target position/angle/voltage, temperatures, ect. (64)
- 3. CAMAC, VXI, Caen:
- In particular bias and current for each detector (70+336=406)
- 4. Physical Data:
- Mean value, width & skewness for PG,GG,Rapid,Lent parameters
(3*1280=3840)
Note: separate for physics trigger and pulser/laser
- 5. Analysis Data:
-
- a. Overlapp coefficients (1280)
- calculate ring average, determine shift parameters
- b. Linearity coefficients (3*70=210)
- determined for PG and GG pulser in dedicated runs
- c. Pedestals (1280)
- determined in dedicated runs
- d. Energy calibration parameters (1280)
- from analysing Alpha source runs
Each parameter should have a name and a number. The frequency of read out
time could be of the order of 10 min for the more frequent ones (2,3),
an hour for others (4), several days for some others (5 a-d) and
variable for the rest (1).
- Notes:
-
on 1.: There should be a mechanism to enter general comments
on 3.: Currently it takes several minutes to read full Caen
system status.
on 4.: There is one trigger which fires the Pulser (IC, Si)
and the Laser (CsI).
on 4.: It takes several runs to have meaningful statistics for
detectors at backward angles
on 5.: Those parameters can be determined nearline (few
hours delay).
on 1-5.: A quality flag (good,bad,doubtfull) could be helpful.
System Layout (W.M.)
As outlined above, the INDRA Monitoring System serves
a dual purpose:
- Online: Monitor system parameters,
log them in a database, give alarms on predefined
conditions and display the time dependence of parameters (trending).
- Offline: Provide information from the database in the most useful
form for the initial stages of the quality control and the
calibration of the experiment.
In other words, the INDRA Monitoring System consists of two segments which
are logically connected by a database.
Clearly, the online segment must be available at GSI and should be
transferable to GANIL for later campaigns. The offline segment
must be available at least at GSI, GANIL and the Lyon computer center and
should allow data access from all sites of the INDRA collaboration.
The two segments exhibit different requirement profiles, the online segment
is a typical process control task, even though only passive monitoring
and no active control is done, while the offline segment is a typical
data mining task.
The software tools used to implement the two segments could thus be quite
different. A possible solution is the usage of a commercial process control
system for the online segment and of relational database queries
(implemented in plain SQL or with some other tool) for the offline segment.
We will have a more detailed discussion on implementation and the tools to
be used after all user and system requirements are known. Too aid this
discussion I have evaluated several process control software systems, with
emphasis on a commercial off-the-shelf (COTS) solution. For details
see Process Control Software for INDRA
Monitoring.
Timelines
- Meeting on user and system requirements in mid December in Paris.
- System decision in mid January.
Created: November 18th, 1997
Walter F.J. Müller