Re: 22GeV update

From: Stephen J. Sanders (ssanders@ku.edu)
Date: Tue Dec 04 2001 - 11:59:23 EST

  • Next message: Flemming Videbaek: "pii cluster"

    Hi Bjorn,
    Now that the paper is out of the way I hope to start getting the calibration
    files for some of the later runs, but for now you may want to check that the
    si pedestals all look OK.  I would expect the gains to be OK since we 
    have not
    seen evidence of these changing significantly. 
    
    I am surprised that the sum energy of the tiles doesn't give the "best"
    measure--if the tiles look strange I would again suspect the pedestals since
    these are known to drift significantly.
    
    ...steve
    
    Bjorn H Samset wrote:
    
    > In the interest of keeping this discussion going, here is a very brief
    > update on 22GeV dNdEta from TPM1. All this is still _very_ preliminary.
    > 
    > I've looked at the different responses of the global detectors using what
    > calibrations I have (for run 4640, mostly), and the only one that looks
    > more or less reasonable at first glance is the Si array hits:
    > 
    > http://folk.uio.no/bjornhs/brahms/22GeV/SiArrayHits_22GeV.ps
    > 
    > I use this response "blindly" to select "most central" events - if this is
    > a very bad thing to do I'd appreciate some feedback.
    > 
    > Again using the geant BB response (assuming 100% tube efficiency) to
    > normalize the number of events, but now doing a much better job of the
    > background subtraction:
    > 
    > http://folk.uio.no/bjornhs/brahms/22GeV/dvf_z_fit.ps
    > 
    > ...I get the following:
    > 
    > dNdEta (eta=0) = 313
    > 
    > Getting closer. There are still some parts of the TPC-specific code that I
    > need to look into more closely, but I'd very much like to hear from
    > Steve/Hiro on the Si response - is this curve usable the way I'm doing -
    > i.e. just using the 200GeV calib blindly?
    > 
    > Ping :-)
    > 
    > --
    > Bjorn H. Samset                           Phone: 22856465/92051998
    > PhD student, heavy ion physics            Adr:   Schouterrassen 6
    > Inst. of Physics, University of Oslo             0573 Oslo
    >                               \|/
    > ----------------------------> -*- <-----------------------------
    >                               /|\
    



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