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Dear John, actually we are still working on it since we noticed that met collection was directly taken by the main collection. We plan to define good objects for met calculation. In principle we define good jets and leptons for our selection. Therefore we did not observe such discrepancy for HT calculation and jet multiplicity cases. However, met and also met related variables show sensitivities for different pu`s. Let us work on met a little bit more and let you know for details, Altan. On May 7, 2013, at 6:05 PM, John Stupak <[log in to unmask]<mailto:[log in to unmask]>> wrote: Jim et al, Altan Cakir, showed yesterday that even calculating the MET from reconstructed objects is very sensitive to pileup, so there may not be much we can do about this (on the snowmass timescale). See slide 6 of the attached talk. That being said, his results contradict what was shown in our meeting, so its unclear what the real story is. John On May 7, 2013, at 10:53 AM, James F Hirschauer wrote: > Hi Sasha, > > Thanks for your nice slides from last week's April 30 meeting: > https://indico.cern.ch/getFile.py/access?contribId=7&resId=0&materialId=slides&confId=249529 > > You show an obvious difference between MET and HT computed by Delphes > and MET and HT computed from selected leptons and jets with pT>25 GeV > and |eta|<2.4. Have you tried loosening the jet selection? Your eta > and pT requirements are removing much of the neutral pileup energy that > is going into the MET sum on slide 3. > > Delphes is not applying any neutral PU correction to the MET sum (I am talking > to the authors about testing this), but Delphes does correct for clustered > neutral PU in the HT sum. > > Best, > > Jim > > > On Apr 29, 2013, at 8:40 AM, Meenakshi Narain wrote: > >> Hi Sasha, >> >> Can you also look at some of the ttbar files at >> http://red-gridftp11.unl.edu/Snowmass/Delphes-3.0.6.1/ >> >> there are 13 and 33 TeV samples, with 0, 50 and 140 Pileup. >> I believe in these samples, the pileup files are different from those which >> Sergei used. If would be a good to have feedback. For the 0 and 50 PU, the >> ttbar are about a few Million events. 140 PU the stats is much lower. >> >> in addition to ttbar there are also many other background samples. >> >> Regards, >> Meenakshi >> >> >> >> >> >> On Apr 29, 2013, at 1:13 AM, Alexandre Khanov <[log in to unmask]<mailto:[log in to unmask]>> wrote: >> >>> Hi Sergei, >>> >>> thanks, it's working now. I looked at available ttbar samples and made some plots: >>> >>> http://hep0.okstate.edu/khanov/snowmass/ttbar/ >>> >>> Could you please take a look and see if they make sense to you? I'm particularly concered about the MET and HT distributions. MET (second column) changes a lot from 0 to 50 to 140 PU. HT (third column) is almost the same for 0 and 50 PU but changes dramatically from 50 to 140 PU. What particularly worries me is that if I just calculate the sum of selected leptons and jets' transverse momenta (columns 4,5) I don't see any big PU dependence. Is it expected? >>> >>> -- Regards, Sasha >>> >>> >>> On Mon, 29 Apr 2013, Sergei Chekanov wrote: >>> >>>> >>>> Hi, Sasha >>>> >>>> Today I was copying new Delphes files, this could case this glitch. It works now. >>>> >>>> Here are recent updates for: >>>> >>>> >>>> https://atlaswww.hep.anl.gov/asc/wikidoc/doku.php?id=snowmass2013:montecarlo >>>> >>>> 1) Corrected truth particles for all top samples (now we store all muons, electrons, taus, bosons and exotic particles, i.e. Z') >>>> >>>> 2) New Pythia8 sample for Higgs+ttbar >>>> >>>> 3) Explained how to read Delphes output without installing ROOT >>>> >>>> best, Sergei >>>> >>>> Sergei Chekanov | WWW : www.hep.anl.gov/chakanau<http://www.hep.anl.gov/chakanau> >>>> =============== | Email: [log in to unmask]<mailto:[log in to unmask]> >>>> HEP Division, ANL | Tel : +01-630-252 6541 >>>> 9700 S.Cass,Argonne,IL 60439,USA | Fax : +01-630-252-5782 >>>> >>>> On 04/28/2013 06:25 PM, Alexandre Khanov wrote: >>>>> Hi Sergei, >>>>> the samples were there this morning but now I'm not able to access them: >>>>> http://atlaswww1.hep.anl.gov/asc/snowmass2013/delphes36/ttbar/mu0/ >>>>> Not Found >>>>> The requested URL /asc/snowmass2013/delphes36/ttbar/mu0/ was not found >>>>> on this server. >>>>> Are you moving the samples around or there is a problem with the server? >>>>> -- Regards, Sasha >>>>> Sergei Chekanov wrote: >>>>> Dear all, >>>>> >>>>> There are a few MC samples with ttbar available for testing: >>>>> https://atlaswww.hep.anl.gov/asc/wikidoc/doku.php?id=snowmass2013:montecarlo#monte_carlo_samples_using_the_snowmass_detector >>>>> >>>>> (low pT ttbar, high pT ttbar and Zprime(3TeV)->ttbar for mu=0,50,140). >>>>> >>>>> The samples were generated using the Snowmass Combined LHC detector: >>>>> http://www.snowmass2013.org/tiki-index.php?page=Energy_Frontier_FastSimulation#Fast_Simulation_and_Pileup_strategy_-_the_Snowmass_detector >>>>> >>>>> best, Sergei >>>> >>> >>> ######################################################################## >>> Use REPLY-ALL to reply to list >>> >>> To unsubscribe from the SNOWMASS-TOP list, click the following link: >>> https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SNOWMASS-TOP&A=1 >> > <cakir_snowmass (1).pdf> --------------------------------------------------------------- Altan Cakir Phone: +49-40-8998-2835 DESY Mobile: +49-151-47074306 Notkestr. 85 Office: Bldg. 1b/1O.215 22607 HH Email: [log in to unmask]<mailto:[log in to unmask]> --------------------------------------------------------------- ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the SNOWMASS-TOP list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=SNOWMASS-TOP&A=1