JME POG CMS Data Analysis School (CMSDAS) exercise

(also used for HATs@LPC)

DAS

Directions for CMSDAS 2018

cmsrel CMSSW_8_0_25
cd CMSSW_8_0_25/src
git clone https://github.com/cms-jet/JMEDAS.git Analysis/JMEDAS
git clone https://github.com/cms-jet/JetToolbox Analysis/JetToolbox -b jetToolbox_80X
cd Analysis/JMEDAS
scram b -j 10
cd test
voms-proxy-init
python jmedas_fwlite.py --files qcdflat.txt  --outname qcdflat.root

Later in the exercise we will do:

cr ClusterWithToolboxAndMakeHistos.py

Pileup & Jet Energy Correction HATS@LPC

Introduction

This Hands on Tutorial Session (HATS) is intended to provide you with basic familiarity with jet energy corrections (JEC) as they relate to CMS. Pretty much all analyses which use jets will need to make use of JECs in some way. Additionally, analyes will probably use the systematic uncertainties for those corrections as well as the jet energy resolution (JER) scale factors and their uncertainties. A general description of the JEC and JER will be provided, as well as several example of how to apply these corrections/scale factors.

More details about pileup and its removal from jets will be given as pileup presents a large issue for current and future analyses. There are several ways to mitigate the effects of pileup and this tutorial will cover the most common of those methods.

Getting Started (Setup)

This tutorial uses Jupyter Notebooks as a browser-based development environment at Vanderbilt. These Jupyter-based tutorials use a pre-configured Jupyter service usable by all CMS members.

Connect to Jupyter

To log in, access the login page and login using your CERN credentials. Once you successfully connect, you should see the following front page

The two most important buttons are

• The new button, which lets you open a terminal or start a new Jupyter notebook.
• The control panel button, which lets you shut down your notebook once you're done. It's helpful to do this to free up resources for other users.

Upload Grid Certificates

We will copy your grid certificates from the LPC cluster, to do this, open the front page (shown above), and click the New box at the top right, then the Terminal option.

This will open a new tab with a bash terminal. Execute the following commands (following the appropriate prompts) to copy your certificate from the LPC to Jupyter (note: replace username with your FNAL username!)

The following command will prompt you for your FNAL password

kinit username@FNAL.GOV
rsync -rLv username@cmslpc-sl6.fnal.gov:.globus/ ~/.globus/
chmod 755 ~/.globus
chmod 600 ~/.globus/*
kdestroy

Initialize Your Proxy at every Login!

If you have a password on your grid certificate, you'll need to remember to execute the following in a terminal each time you log in to Jupyter. Similar to the LPC cluster, you will get a new host at each logon, and the new host won't have your old credentials.

Each time you log in, open a terminal and execute:

voms-proxy-init -voms cms -valid 192:00

Checkout the code

Open up a terminal and run the following command from your home area:

wget https://raw.githubusercontent.com/cms-jet/JMEDAS/master/setup-libraries.ipynb

Go back to your Jupyter browser page and open/run the newly downloaded notebook (there is only one cell to run). This will cehckout the code and setup your environment for future use. At this point you can continue on to the Tutorial section.

Note: If you'd like to set this code up to be used without Jupyter, follow the directions below. This is not necessary for the HATS exercises.

Standalone directions without Jupyter

cmsrel CMSSW_9_4_8
cd CMSSW_9_4_8/src
git clone https://github.com/cms-jet/JMEDAS.git Analysis/JMEDAS
git clone https://github.com/cms-jet/JetToolbox Analysis/JetToolbox -b jetToolbox_94X
cd Analysis/JMEDAS
scram b -j 4
cd test
voms-proxy-init

Tutorial

Once you've completed the setup instructions, information on the separate tutorial can be found in the test subdirectory.