Re: Charge of particels.

From: I. G. Bearden (bearden@hehi03.nbi.dk)
Date: Thu Jun 22 2000 - 11:07:46 EDT

  • Next message: Konstantin Olchanski: "Re: Charge of particels."

    Flemming Videbaek wrote:
    
    > Just one (trivial) comment of the charge discussion.
    >
    > The BrModuleMatch class that is used multiple places in the tracking
    > evaluates p/q as a signed value for each match. Thus the sign of the charge
    > is determined tough not the actual value of course. One may refit the value
    > of momenta later by other methods but one should not re-do the sign later.
    >
    
    Of course it evaluates p/q, that is what magnets do.  I was only making the
    (trivial) point that
    there will be particles for which TMath::Abs(charge)>1.  Sadly, there will not
    be many such
    particles, but the few we get are interesting (to me, anyway) and we should
    not eliminate the
    possibility of looking at them by non-optimally clever decisions.
    The refitting is actually just a multiplication, though, isn't it?  i.e. if
    q=2, p_correct = 2*p_reconstructed.
    
    Also, I think I have sorted out the geometry problems I mentioned earlier, but
    now
    I'm a bit dizzy from playing with the 3D stuff in root.
    
    
    >
    > Flemming
    
    Cheers,
    
    --
    Ian--------------------------------------------------------------------
    | I.G. Bearden                                                         |
    | Niels Bohr Institute Tb 3    email:      bearden@nbi.dk              |
    | Blegdamsvej 17               phone:      (+45) 35 32 53 23           |
    | København Ø                    FAX:      (+45) 31 42 10 16           |
    | Danmark                                                              |
     ----------------------------------------------------------------------
    



    This archive was generated by hypermail 2b29 : Thu Jun 22 2000 - 11:11:52 EDT