From kinyip@fnal.gov Tue Jun 6 12:00:53 2000 Date: Tue, 6 Jun 2000 11:36:23 -0500 From: Kin Yip To: Gustaaf Brooijmans Cc: Oleg Kouznetsov , Rick Jesik , Daniela Bauer , vj@bnl.gov, Serban Protopopescu Subject: Re: Bs MC file history? Hi, Actually, thinking a bit harder, in the particular case of Oleg, we don't need to introduce our OWN Psi and Phi. Oleg's or Gustaaf's user.dec file only wants to decay Bs and Bs_bar in certain way and not even other B particles. QQ is only used when you stop a particle such as Bs from being decayed by Pythia. So, if Psi or Phi is from elsewhere (ie. not from Bs or Bs_bar), it will be decayed by Pythia already and QQ will not be used. In this particular case, I think we don't actually need to create OUR OWN particle. Kin +++++++++++ +++++++++++++ ++++++++++++ ++++++++++++ ++++++++++++ +++++ From gusbroo@fnal.gov Tue Jun 6 11:12:37 2000 Date: Tue, 06 Jun 2000 09:54:35 -0500 From: Gustaaf Brooijmans To: Oleg Kouznetsov Cc: Rick Jesik , Daniela Bauer , Kin Yip , vj@bnl.gov, Serban Protopopescu Subject: Re: Bs MC file history? Hi- Looking at the files used to produce these events, the explanation for the problem we saw is fairly simple. (For those who may not be aware of it, in the files Oleg produced, the B_s decays to two particle with ID=0 in the MCKineChunks, these particles then decay to mumu/ee and KK respectively, indicating they are j/psi and phi respectively). In the custom qq decay table Oleg used, he redefines two particles: PARTICLE MYPHI 393 -1 1.019413 0.0 1.0 0.000000 0.0044 0.999 1.039 PARTICLE MYPSI 394 -1 3.096880 0.0 1.0 0.000000 with arbitrary ID's 393 and 394, which are unknown to our translation programs. I suppose the reason Oleg did this is to be able to change the phi and j/psi decays only for those that were produced in the B_s decays. So if you want to do this, you also _need_ to define the PDG code for your "custom particles": PARTICLE MYPHI 393 -1 1.019413 0.0 1.0 0.000000 0.0044 0.999 1.039 PARTICLE MYPSI 394 -1 3.096880 0.0 1.0 0.000000 PDG MYPHI 333 PDG MYPSI 443 Otherwise, the program has no way of knowing what your custom particles are. With that in, everything works fine. You can find a corrected user.dec file at /prj_root/811/tauid_2/gusbroo/bspsi/test/user.dec Cheers- Gustaaf On Tue, 6 Jun 2000, Oleg Kouznetsov wrote: > > Hi Rick, > I put on the RunIIB disk the files which were used > to generate bs_psi_phi537.evt sample. > > ** Pythia **** > /projects/786/mub_3/RunIIB/kuznets/user.dec > /projects/786/mub_3/RunIIB/kuznets/pythia.cards > > ** D0gstar *** > /projects/786/mub_3/RunIIB/kuznets/framework_mckine.rcp > /projects/786/mub_3/RunIIB/kuznets/run.test_mckine.csh > > Let me know if something wrong will be found in these > files. > > It seems to me that I used t00.82.00 release: > /d0dist/dist/releases/t00.82.00/bin/IRIX6-KCC_3_3/MCpythia.x > and so on.... > Regards. Oleg > > > On Mon, 5 Jun 2000, Rick Jesik wrote: > > > Hi Oleg, > > > > There have been some quastions about the Bs->J/psi+phi MC events you > > generated. Can you please give us the answers as soon as possible? > > > > thanks, Rick > > > > > > Gustaaf Brooijmans wrote: > > > > > > Hi Rick- > > > > > > I have received some email stating that there was a problem with some lost > > > particle IDs in B_s->j/psi phi events > > > (/prj_root/786/mub_3/RunIIB/kuznets/bs_psi_phi537.evt) > > > > > > Looking at that file, that appears to be true indeed, but when I generate > > > b_s -> phi j/psi (or any other fun decay like psi(2s) f0, ...), everything > > > is fine. > > > > > > So, since I can't reproduce this by myself, could you give me the details > > > on how this file was produced (generator version, release, cards, etc.)? > > > > > > Thanks > > > > > > Gustaaf > > > > > > --------------------------------------------------------- > > > Gustaaf Brooijmans > > > Fermilab, MS # 357 Tel: +1 (630) 840 4269 > > > P.O. Box 500 Fax: +1 (630) 840 8481 > > > Batavia, IL 60510 > > > --------------------------------------------------------- > > > > Vivek Jain wrote: > > > > > > Hi Rick, > > > > > > I am looking at this file called > > > /prj_root/786/mub_3/RunIIB/kuznets/bs_psi_phi537.evt > > > > > > Some of the information in the MCKineChunk is messed up. Specifically, > > > the links to parents (and daughters) of particles is screwy. > > > For instance, the daughters of Bs, which should be Phi and Psi, seem to be > > > called Color. Their daughters are mu+mu- and K+K-. > > > > > > Were these events generated using Pythia? Serban thinks that somehow the > > > translation routine (which translates Isajet ID <-> Pythia (or PDG) ID) > > > got messed up for Phi's and Psi's! > > > > > > I noticed this because my code is set up to look at ID's of parents and > > > daughters of particles. > > > > > > Vivek > > > > > > p.s. If you are interested you can look at the dump (on d0mino) > > > > > > /projects/736/mc_3/vj/development/t91/bin/IRIX6-KCC_3_3/reco_Bs.dump > > > > > --------------------------------------------------------- Gustaaf Brooijmans Fermilab, MS # 357 Tel: +1 (630) 840 4269 P.O. Box 500 Fax: +1 (630) 840 8481 Batavia, IL 60510 ---------------------------------------------------------