ECAL Shifting Notes
Before an ECAL Shift
There are several things to do before your first DGL/DoC shift. First of all, ensure that you have a way to get to the run meeting at P5. The CERN
Carshare service
may be of use for this. Note they only provide manual transmission vehicles. The meeting is at 9:30AM Monday-Thursday, and 10:00AM on Friday-Sunday, and takes place in building xxx. Go in the main door and turn right. You need to be at the first meeting to exchange phones. As a DGL, you can get away with connecting to the meetings by
EVO
, but it may be easier to connect with the
DoC if you are there in person. You can find the meeting by searching for "CMS Run Meeting." It is password protected, so you should ask the
DoC what the latest password is a few days ahead of time.
In addition, the control room at P5 requires EDH access. The first thing to do is complete the
safety training
. To access P5 and the control room, you need basic safety (levels 1 and 2), as well as level 3 and 4C (4C is specific to
CMS). Note that it can take some time to go through the safety information and take the tests, so be sure to do this before your first shift.
Once you complete the training, go to
EDH
and, click the "Access Request" tab. Request access to LHC/LEP P5, then select
CMS control room.
You also need a security certificate to get access to the DQM plots. It is recommended that you use Firefox. Follow these
instructions for a CERN CA certificate. You can also get a grid certificate
here
from the DOE. Then follow the procedures listed on the
USCMS page
. For accessing DQM plots, a CERN CA certificate seems to be enough (?).
Subscribe to ECAL
e-log
by clicking the Config button, and checking off "ECAL," and "Shift Leader," then click save on the top left. The page does not automatically refresh, so it's helpful to get automatic updates when there is an entry.
Helpful Links
Summary of what is going on at P5 can be found here:
http://cms-project-ecal-p5.web.cern.ch/cms-project-ECAL-P5/
Most of the links (left side of the page) you need to can be found from here. The first thing to look at is the RFM (
DoC used to be called RFM)
manual.
One of the main things the DGL is supposed to do is look at the Data Quality Management (DQM) plots, which can be found
here
. At least for Ecal Barrel (EB)/Ecal Endcap (EE), there is also the "Describe" button, which gives you info for each histogram.
Instructions for examining DQM plots
These are some basic instructions given to me by the
DoC which describe which plots to look at:
DQM Shifter view:
Workspace Summary & then double-click on EB or EE.... => histogram Set & then also Layouts 00 Shift
ES ==> Standard "complete" set
DQM: Workspace
EcalBarrel ==> Layouts: 01 ECAL Shift
Normally check all the Folders: 01-09
At least for the 1-D plots, you should find References (Green) - albeit at lower Lumi/Pile-Up...
EcalEndcap ==> Layouts: 01 ECAL Shift
Normally check all the Folders: 01-09
At least for the 1-D plots, you should find References (Green) - albeit at lower Lumi/Pile-Up...
EcalCalibration ==> Layout:
EcalCalibration: 3 folders - supposed to be "obvious" - occasional Red bits OK...!
EcalPrershower ==> I think ALL the histograms immediately appear on the "top" Page... - supposed to be "obvious"
There are two main categories of 2D plots: integrity plots and occupancy plots, and these involve different color schemes to see whether things are working correctly, described below:
- Most things should go RED when they go wrong, Yellow means poor statistics, and White means empty (no events in that bin) - but this MAY be OK, in some circumstances.
- Some "occupancy" plots are "just" in Blue, so you should look for localised dark (High occupancy) regions, or extensive regions too pale...
Some plots display quanitites such as the energy, and these plots may be "temperature" plots where the z axis is color scaled, in which case red doesn't necessarily mean bad, so look at the description carefully.
It's a good idea to "practice" on known good runs. Ask the
DoC for a recent good run to look at.
Note that the green reference lines just come from a good previous run.
There are two DQM pages that can help understand the plots. This
page is somewhat out of date however. This
page has some complementary information.
Pedestal Runs
Every week, when we don't have beam we need to calibrate ECAL with pedestal runs.
Ask shift leader if we can have local control of ECAL.
Run Control Monitoring system
user:***
psswd: ****
check to make sure that there is no one else using ECAL. So go to Running Configurations
go to Configuration Chooser/
LocalReadout/Default/ECAL/CH4 ==>Create
Unlock
Initialize
Take Pedestal_TTCci run
Choose subdetector, so for example EE+ / EE-, so that the DQM job can finish, click apply ==> Configure. Then start.
Next do EB+ pedestal, same set of instructions.
Test Pulse_TTCci
When finished click destroy
Check ECAL private DQM.
Update ECAL Log. Use WMB to check run numbers.
Tell shift leader we are done and that he can put ECAL back into global.
Abreviations
There are lots of abreviations to learn, and
CMS has a page with lots of helpful abreviations and acroynms
here. I have listed a few that will be useful for ECAL shifiting below.
EB - ECAL barrel
EE - ECAL endcap
ES - ECAL pre-shower
IT - Integrity task, used for examining data quality (example EBIT stands for ECAL barrel integrity task)
OT - Occupancy task used for determing whether there is data in a given channel (example EBOT stands for ECAL barrel occupancy task)
APD - Avalanche photodiodes
PN - Another kind of diode used for looking at LASER calibration signal, more stable than APDs
Rechit - Reconstructed hit
Digi - Digitized raw data
DCC - Data Concentration Card
DCS - Detector Control System
DQM - Data Quality Management
TP - Trigger primitives
ZS - Zero Supression
FED - Front End Driver
CCS - Clock Control System
TCC - Trigger Concentration Card
ttcci (?)