[[snowmass2013:montecarlo| <<back]]

==== Higgs plus ttbar  ====


Here are samples of [[https://cp3.irmp.ucl.ac.be/projects/delphes | Delphes 3.08]] events generated for the **14 TeV** center-of-mass energy (pp collisions). The events are generated for 0, 50 and 140 pileup scenarios. All data  are stored in the  ROOT format  using the standard [[https://cp3.irmp.ucl.ac.be/projects/delphes | Delphes]] output.
Therefore, it is recommended to install [[https://cp3.irmp.ucl.ac.be/projects/delphes | Delphes]] and look at the example explaining how to read such ROOT files (see the directory "Examples" inside the Delphes package).
The samples use the "Snowmass" detector geometry. 
See [[http://www.snowmass2013.org/tiki-index.php?page=Energy_Frontier_FastSimulation| this wiki]] for details. 

 
==== How to download ====

Please read the Section [[snowmass2013:download| How to download]]. You need a python script "download.py"



==== Higgs plus ttbar ====


The samples are generated for Higgs to ttbar, all decays, using PYTHIA8 (14 TeV collisions).
In total, there are 96 files per sample (mu=0,50,140), with 1000 ttbar  events in each. Thus the total number of events is  96000 signal events per sample. Processes included:

<code>
 g g -> H t tbar (SM)
 q qbar -> H t tbar (SM)
</code>

For 1000 generated events, the log file:
<code>
== Cross section for this run=2.369e-01 pb
== Events for this run=1000
== Luminosity for this run=4.222e+00 fb-1
</code>
(total lumi is 403 fb-1 for 96000 events)
Look at PYTHIA8 [[http://mc.hep.anl.gov/asc/snowmass2013/delphes36/httbar/log/A_RUN_signal.log.gz | log file]] used to generate such files. This is [[http://mc.hep.anl.gov/asc/snowmass2013/delphes36/httbar/log/analysis.ini | PYTHIA8 settings]].


=====  No pileup =====

Get the generated ROOT files from  [[http://mc.hep.anl.gov/asc/snowmass2013/delphes36/?dir=httbar | this  download link]]. Here is an example for downloading 5 files: 
<code>
python download.py 5  delphes36/httbar/mu0  pythia8_httbar_delphes306
</code>
(set 5 to 96 to download all)


=====   <mu>=50 =====

Get the ROOT files from  [[ http://mc.hep.anl.gov/asc/snowmass2013/delphes36/?dir=httbar/mu50| this  download link]].
Here is an example for downloading 5 files: 
<code>
python download.py 5  delphes36/httbar/mu50  pythia8_httbar_delphes306_mu50 
</code>
(set 5 to 96 to download all)


===== <mu>=140 =====

Get the ROOT files from  [[http://mc.hep.anl.gov/asc/snowmass2013/delphes36/?dir=httbar/mu140 | this  download link]].
Here is an example for downloading 5 files: 
<code>
python download.py 5  delphes36/httbar/mu140  pythia8_httbar_delphes306_mu140
</code>
(set 5 to 96 to download all)

==== How to analyze using ROOT ====

If you need to find the effect of pileup on top reconstruction or a jet measurement, you need to  run the analysis code over signal MC and then over the signal+pileup MC files.
Read [[snowmass2013:analyse_d3]]

==== How to analyze without ROOT ====

In some cases, you may not have ROOT installed to read the Delphes files. In this case, you can use
ROOT files converted to the ProMC format which can be read without ROOT (using C++, Java, Python). Read 
[[snowmass2013:analyse_d36_promc| how to read Delphes3 output without ROOT]].


 --- //[[chekanov@anl.gov|Sergei Chekanov]] 2013/03/06 20:48//