LPC Computing

Muon Tutorial

This Tutorial is obsolete! It was developed with older versions of the
CMS software. In addition the computing system was upgraded several times
since the tutorial was given early in 2004. You might still want to browse
the pages to get an overview but the hands on examples will not work anymore.

We are in the process of developing a new tutorial that works in the new
software and computing environment and that will utilize more up to date CMS
software.This is currently work in progress:

New Tutorial Scripts

Muon Physics Tutorial

Introduction

The tutorial described here was part of the "Joint CDF/D0/CMS Muon Workshop."
The agenda of this workshop can be found here:
http://agenda.cern.ch/fullAgenda.php?ida=a041040

The tutorial on the second day of this workshop consisted of presentations in the morning and hands on exercises in the afternoon.

Introduction to the FNAL UAF (pdf, 1.6 mb)
Muon Reconstruction Tutorial (pdf, 6.0 mb)
Introduction to Analysis with DSTs (pdf, 367 kb)

Disclaimer: this is only an example to get going! Remember that OSCAR and ORCA are works in progress! We want to demonstrate how to work within the CMS environment setup on the UAF farm at FNAL. All examples were created and tested on Redhat 7 based systems (don't forget the PROC_RESOURCES=RH7 statement in the jdf file) and will not!! work on the RedHat 6 systems. We will use some simple physics analysis to demonstrate how:

- Monte-Carlo events are generated and stored (CMKIN)
- The CMS detector is described and its interaction with particles are simulated (OSCAR)
- Simulated events are digitized (ORCA)
- To create DST's starting from the digitized events

In addition we will learn how to:

- Setup the CMS software environment here at Fermilab
- Use the farm for a small MC production
- Generate a MC sample, convert the ntuple with h2root into a root file,...
- Use root to make a few plots on generator level
- Run the generated events through OSCAR the GEANT4 base detector simulation.
- Run the digitization step using ORCA
- Run some ntuple makers on the ORCA output
- Do some simple analysis

Click the links below to start the exercise. The physics analysis we will use is a Z' with a mass of 700 GeV that we force to decay into 2 muons. (This actually might be one of the first discoveries at the LHC). The scope here is to learn about the computing environment and to do a very simple analysis. In this exercise we don't mix in pile up (yet)!

Be aware that you have to do the exercise in sequence! (with the exception of the last bullet which can be executed without whenever)

The figure below shows the simple and robust processing model we will use in all the examples involving the farm to process events in parallel. When the process starts all the input data is staged in from Mass Storage.

Then all the libraries are loaded and all necessary database constants (geometry ...) are read in. During the processing the nodes are completely independent all the output is to local disk. In the end the results are stored in Mass storage. This is very robust all nodes are completely independent. In case a process fails we just have to resubmit that process.

For Tutorials concerning CMKIN and the CMS OO software have a look at the Tutotials given at CERN :

The Tutorial main page: http://cmsdoc.cern.ch/cms/software/tutorials/
Absolute beginner: http://cmsdoc.cern.ch/orca/Tutorials/20031114-CERN/NewUser/
Full analysis chain: http://cmsdoc.cern.ch/orca/Tutorials/20031128-CERN/FullChain/Contents.html
COBRA: http://cobra.web.cern.ch/cobra/Tutorial743/index.html
Tracking: http://cmsdoc.cern.ch/orca/Tutorials/20040109-CERN/index.html

Other good web pages to find information are:

http://cobra.web.cern.ch/cobra/Tutorial743/index.html
http://cmsdoc.cern.ch/cmsoo/cmsoo.html