Документ взят из кэша поисковой машины. Адрес
оригинального документа
: http://theory.sinp.msu.ru/pipermail/comphep-common/2004/000113.html
Дата изменения: Thu Apr 18 22:50:41 2013 Дата индексирования: Fri Feb 28 06:31:27 2014 Кодировка: |
Dear David! I think that we fix the bug. Please take last version of CompHEP from the Web: http://theory.sinp.msu.ru/comphep Many thanks for report! If you wish to receive regular information about CompHEP project, please sign on the mail list: http://theory.sinp.msu.ru/mailman/listinfo/comphep-common Best wishes, Alexander On Mon, 2004-04-26 at 23:20, David C. Papencordt wrote: > Dear Alexander! > Some time ago, I wrote you about my problems with a special compHEP > process (see below). Now I'd like to know if you already analysed it? > > Looking forward to an answer and best wishes, David > > > > Am Die, 2004-02-10 um 10.45 schrieb Alexander Kryukov: > > Dear David! > > > > Thanks a lot of the report. We investigate the problem and report about results > > as soon as possible. > > > > Best wishes, Alexander > > > > p11y001 at public.uni-hamburg.de wrote: > > > Dear Alexander Kryukov! > > > > > > I'm using compHEP to simulate the process pb,pb->m,M and I have the problem of > > > an unexplainable Cross Section. Perhaps you can help me with this. > > > > > > I will specify my settings first: > > > > > > compHEP version: 4.2.0 > > > model: SM, Feynman gauge > > > pb consist of: u,U,d,D,s,S,c,C,b,B,G > > > CMS energy: 14000 GeV > > > structure function: both cteq6l1 > > > cuts: T3 6 7000 > > > T4 6 7000 > > > A13 5 175 > > > A14 5 175 > > > Distributions: T3 0 7000 > > > T4 0 7000 > > > C13 -1 1 > > > C14 -1 1 > > > > > > > > > After generating events, I have the following Cross Sections: > > > uU->mM: 7.28159E+02 > > > dD->mM: 3.21322E+02 > > > cC->mM: 6.35663E+03 (<- much to high?) > > > sS->mM: 1.73509E+02 > > > > > > It seems to me, that the CS from the subprocess cC->mM is much to high, while > > > the others seem to be ok. > > > The same problem occurs, when I try to estimate the number of events (N) per > > > sec. For this I use the vegas integration and display T3 with 2 bins. While the > > > the second bin is negligible, I take the CS from the first one and calculate N > > > with an expected Luminosity (L) of 10^34 (N=CS*L). > > > Here are my results: > > > uU->mM: 28,8 events per sec > > > dD->mM: 12.8 e.p.s. > > > cC->mM: 447 e.p.s. (!) > > > sS->mM: 7 e.p.s. > > > > > > As you can see, because of the very high CS of the cC subprocess, I have even > > > more events than from the uU one, althouhg I consider a proton - proton collision! > > > > > > I have no explanation for that. > > > > > > Perhaps you can help me with this? Is there a known bug in the program? > > > > > > Thanks a lot! > > > Yours sincerely, > > > > > > David Papencordt > > > > -- > > Dr. Alexander Kryukov > > Inst. of Nucl. Phys, Moscow State Univ,| INFN, Padua (until 11/02/2004) > > Leninskie gory-1, 119992, Moscow,RUSSIA| Via Marzolo 8, 35131 Padova-Italy > > +7(095)939-2875, bld. KFVE, room 404 | Phone: +39(049)827-7099, Off. 139 > > > > -- Alexander Kryukov <kryukov at theory.sinp.msu.ru> SINP MSU