My Data Samples


The first two digits of the 6 digit code after mc08 (for example) implies the COM energy of the sample:

10 = 10 TeV 00 = 14 TeV





Z Boson




How To Make a MC Production Request

To Start & Overview

This might vary slightly depending what group you are in. But having gone through the process now, I think a guide would be very useful, hope it helps!

On your groups home Twiki page, there should be a page dedicated to how to make Monte Carlo requests, but in general you can go to the Monte Carlo Working Group page, where they list the relevant contacts for every group:

The General List of Pre-requisites for a MC Production Request are:

Note, before any of the below steps, you should contact your group convenors, and the MC Production Contact for your group, to let them know of your intentions, and ask if it would be okay to go ahead and start making the request.

  • Provide a joboptions file
  • Provide relevant cross-sections, evgen efficiencies, and number of events requested, along with centre of mass energy, and code version you are setup in, also the event generator version you are using.
  • Make Validation Plots, from a small sample you make with your joboptions file. I.e. Provide relevant plots that show the joboptions file produces what you would expect.
  • Put the Joboptions files, Validation plots, and all information so far on your groups relevant "Validation Plot" page under the process for which you are asking for samples, if there isn't one, create a new twiki page that is for your process.
  • Contact your groups Monte Carlo Production Contact, sending them the link to the Twiki page, along with the joboptions files attached to the e-mail, and all the information so far requested (even though it is already on the Twiki). They will take the request from here, and let you know the outcome.

Setup Area

First of all, you need to setup your work area, this is best done on lxplus. Make your cmthome area and download a package to work in such as UserAnalysis. This is explained how to do so on the coding tips and tricks page.

Get joboptions files to use/modify

You can find the joboptions files for all of the Official Monte Carlo Samples here:

All I did, was find the Particle and Decay I was interested in, take the joboptions file, and modify it for my own needs. Most of the time this just involves changing the Mass or some Coupling, that is well documented in the joboptions file itself. If you want to do something more drastic however, like make a new sample that has not even been roughly coded before, then I have not done this, but I would suggest you start by looking at multiple joboptions files, such as if you wanted to simulate G->ee and G->mumu, where currently there are only seperate files that do this; Take the two seperate files, and copy the lines which correspond to the decaying of each process into a new file, start building your joboptions that way, and after testing with a well known joboptions to see what you would expect, test yours and see if it makes sense.

Making a Test Sample

Once you have your area setup, sourced, and have made your joboptions file:

Go to your run directory such as:

> cd testarea/15.3.0
> cd PhysicsAnalysis/AnalysisCommon/UserAnalysis/run

You need to obtain the following four files via, although the latter most is really just an example file:

> get_files PDGTABLE.!MeV
> get_files
> get_files
> get_files

Then you are ready to make your first sample, how first you have a choice. If you want truth, jet, and missing et information in your sample you should use:

> 1 1 5000 1 evgen.pool.root sampleB.AOD.pool.root

However if you only need the normal information (which is all that is generally needed for validation plots, and I recommend), use:

> 1 1 5000 1 evgen.pool.root atlfast.AOD.pool.root genfast.NTUP.pool.root

Note here, that is your joboptions file, and 5000, is the number of events you are going to make in your sample. The other file names are your output. I would recommend redirecting these to your tmp directory on lxplus as they can be 100mb big or so. Just remember to send them to linappserv1 or somewhere before you next log off so they don't disappear!

Making Validation Plots & Collecting Information

The next step is to take one of your no doubt already existing analysis programs, and strip it down so all it does it create plots of basic things like the, et spectrum, eta spectrum, and invariant mass, as an example. Apply no cuts, as you just want to see what the sample looks like. Save these plots, and include them with all the other information that you will eventually upload.

Important! When the job finishes running, you will be left with a number of log files, namely csc_evgen08.log and csc_genAtlfast.log, you will want to keep these files as they contain all of your cross section information!!! Also remember to take note of the event generator efficiency, which is usually set to about 0.90, and can be found on the last line of your joboptions file usually. You will also want to look through them to see exactly what version of Pythia you are using, if you haven't taken note of it before now.

Finishing up

Now you have all your relevant information, go to the Validation Plot Twiki Page, and upload all of your information, this looks best in a table, you can just do what I did and look at a previous request, and take their format. The basic format you want though would be something like this:


Joboption for generation under Pythia 6.420 :

Release E CM G* Mass k/Mpl N Evts xsec x BR Validation plotsSorted ascending
15.2.0 10 TeV 500 GeV 0.01 5 000 79.5 fb Electron pt, electron eta, G Mass
15.2.0 10 TeV 1000 GeV 0.01 5 000 2.17 fb Electron pt, electron eta, G Mass
15.2.0 10 TeV 1000 GeV 0.1 5 000 214.2 fb Electron pt, electron eta, G Mass

Generator Efficiency = 0.90

Now all that's left to do is send all of this information, along with the joboptions file(s), and a link to the Twiki page along to your MC Production representative, and everything should be taken out of your hands from there!


This topic: PP/Public > TWikiUsers > DanielHayden > DanielHaydenDataSamples
Topic revision: r8 - 24 Jan 2010 - DanielHayden
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