1 IST layer
Updated on Fri, 2007-11-16 12:33. Originally created by nieuwhzs on 2007-11-16 12:32.Speaker : Gerrit van Nieuwenhuizen ( MIT )
Talk time : 13:40, Duration : 00:10
AOB
Updated on Fri, 2007-11-16 12:34 by nieuwhzs. Originally created by margetis on 2007-11-16 11:30.Single track efficiencies
Updated on Fri, 2007-11-16 11:28. Originally created by margetis on 2007-11-16 11:28.QA on 0.5x luminocity
Updated on Fri, 2007-11-16 12:55 by kapitan. Originally created by margetis on 2007-11-16 11:28.Speaker : Jan
Talk time : 13:00, Duration : 00:20
See hypernews for his web links
Autobuild & Code Sanity
Updated on Wed, 2024-12-11 13:11 by genevb. Originally created by jeromel on 2007-11-16 10:58. Under:This page will contain results from code-sanity tools i.e. tools checking for code syntax, memory leak, profiling etc ... and tips on how to correct those problems.
Comparing Pion-Kaon correlations from data and Therminator
Updated on Fri, 2007-11-16 09:31. Originally created by kisiel on 2007-11-16 09:31.Reference
Talk time : 00:00, Duration : 00:20
www.star.bnl.gov/protected/hbt/kisiel/071116/PionKaonYlms3Therminator.php
A Brief Overview of the New Pixel Fast Simulator
Updated on Thu, 2007-11-15 13:32. Originally created by wleight on 2007-11-15 13:24.The new StPixelFastSimMaker imposes the pixel structure on the PXL detector and the strip structure on the IST detector. For each event the simulator loops over StMcPixelHits, determines which p
g-g suppression in Pythia
I'm concerned about an apparent deficit of g-g scattering events in our CDF Tune A Pythia samples. I first noticed this deficit when I was looking at MC asymmetries for pi-minus production, where the difference between asymmetries from g-g and q-g events is extreme. For reference, here is Vogelsang's prediction for the subprocess mixture for inclusive pi0 production:
Compare that to the following plot from Pythia for pi-plus production after combining partonic samples starting at 3_4:
If I add 2_3 GeV the gg contribution at low pT gets a boost, but I'm still seeing ~zero pions from g-g scattering at 8 GeV, where Vogelsang predicts 20% g-g.
Renee suggested skipping the observables and just plotting the event partonic pT. The turnover from gg to qg occurs at 3 GeV ... seems too low to me. On the other hand, the mixture is ~20% g-g at 16 GeV, which seems about right.
One other tidbit for any Pythia tuners out there. When I was running standalone Pythia to get the various partonic xsections for weighting purposes I saw a number of advisory warnings like
Advisory warning: maximum violated by 1.120D+00 in event 625
XSEC(28,1) increased to 5.982D-01
in this case, I was running the 5_7 sample. The initial max value for the q-g xsec was 5.3392D-01, and the final measured xsec was 1.515D-01. Not sure if it's significant.
Update 11-19-2007
I looked into the relationship between charged pion p_{T} and event partonic p_{T} in more detail. Here are plot of charged pion multiplicity and mean pion p_{T} versus event p_{T}:
so g-g events actually produce more charged pions per event, but these pions are all at low p_{T}. The second conclusion is reinforced by the PDF I've linked at the bottom of the page, which shows pion p_{T} spectra split by subprocess for a range of partonic p_{T} bins. The g-g events have a much steeper slope. Those plots are not normalized by the # of events per subprocess, so the conclusion about the number of pions per event is not immediately evident.
Update 11-27-2007
I tried manually rescaling the g-g scattering contribution to the PYTHIA asymmetries; it looks like increasing the g-g by a factor of 5 does a decent job of reproducing the NLO theoretical predictions:
References
Agreement Between "Polarized" Pythia and NLO pQCD
Updated Charged Pion A_{LL} predictions
Parallel Photon Studies
Updated on Thu, 2007-11-15 11:39. Originally created by rcorliss on 2007-11-15 11:13.In working toward a prompt photon cross section measurement, we are using two analyses in parallel. The first is a two dimensional fit using parameters identified in the earlier OPAL and ZE
FAQs and Tips
Updated on Wed, 2007-11-14 20:01 by testadmin. Originally created by wbetts on 2007-11-14 19:58. Under:Software Site Licenses
Do we have a site license for software package XYZ?The answer is (almost) always: No!
nodeaccess: Access settings by a user for a specific node
Updated on Wed, 2007-11-14 14:39. Originally created by chajecki on 2007-11-14 14:39.Nodeaccess: settings for a specific node type (admin settings)
Updated on Wed, 2007-11-14 14:35. Originally created by chajecki on 2007-11-14 14:35.Updated look at Electrons in BEMC for 2007
Updated on Mon, 2007-11-19 15:20. Originally created by mattheww on 2007-11-14 14:27.Nodeaccess: allowed roles (admin settings)
Updated on Wed, 2007-11-14 14:31. Originally created by chajecki on 2007-11-14 14:22. Under:Nodeaccess: allowed roles (admin settings)
Updated on Wed, 2007-11-14 14:19. Originally created by chajecki on 2007-11-14 14:19.AOB
Updated on Tue, 2007-11-13 17:04. Originally created by matis on 2007-11-13 17:04.Reference
Talk time : 00:40, Duration : 00:20
Software Status
Updated on Tue, 2007-11-13 17:03. Originally created by matis on 2007-11-13 17:03.Reference
Talk time : 00:20, Duration : 00:20
Response to Tim's E-mail
Updated on Tue, 2007-11-13 17:05. Originally created by matis on 2007-11-13 17:03.Reference
Speaker : All
Talk time : 00:00, Duration : 00:20
(If you have not received, it send a message to HM.)
Comparison between Normal and Test Runs (TPC Drift Problems)
Updated on Tue, 2007-11-13 14:19. Originally created by trent on 2007-11-13 14:19.This is my first post to drupal so I will limit it to two graphs
of the multiplicities for nTracks and nPoints for jets, comparing
New polarized gluon distributions in Pythia
Updated on Tue, 2007-11-13 16:19. Originally created by kocolosk on 2007-11-13 11:29.So we now have access to a wide variety of gluon polarization parameterizations in our Pythia afterburner covering the regions between GRSV -std and -max and between GRSV -zero and -min. Dave Staszak documents the details of the new distributions at
http://www.star.bnl.gov/protected/spin/staszak/2006/Sims/trigBias/trigBias.html
Here are plots of the raw charged pion asymmetries obtained from these grids (p070 excluded because of a bug on my part):
I suspect the problem with the pi-minus asymmetries can be traced to a lack of gg contributions. For more information see Agreement Between "Polarized" Pythia and NLO pQCD. In the remainder of this document I'll stick to analyzing pi-plus data.
I've attached multi-page PDF at the bottom of the page. Each page of the PDF plots, for a give input gluon polarization distribution A_{LL}(trigger) - A_{LL}(no trigger) as a function of pion p_T. There are six plots on each page; one for each trigger in (minbias, HT1, HT2, JP1, JP2) and then the raw A_{LL}(no trigger) distribution itself in the bottom right. I believe one way we can obtain a systematic uncertainty from plots such as these is to calculate a double-sided max( delta A_{LL}, uncertainty on triggered A_{LL} ) for each pT bin we use to make our measurement.
One question is which grids are appropriate ones to use for calculating the systematic. GRSV-max has been excluded in other measurements, so I don't think it's appropriate. All other grids are fair game, which means the systematic will likely be derived from GRSV-min and p070 (once I rerun; use p060 for now).