Dear collegues,
 
here is the  summary of the Test Beam Analysis Meeting
held on 30 September 2000.
This summary as well as links to presentations given 
at the meeting can be found on the web through the official
Testbeam Analysis home page 

http://troncon.home.cern.ch/troncon/testbeamhome.html

Presentations are also put in EDMS.

Best regards,

Clara Troncon
=======================================================================

           Summary of the Test Beam Analysis Meeting
           held on Saturday 30 September 2000.   

     
     Depletion depth for oxygenated sensors           Mario Aleppo
     --------------------------------------           ------------
Analyzed  data of irradiated prototype2 sensors 
collected during June (Oxy1, Oxy2, Oxy3, Notoxy1, Notoxy2) 
and July (GE_b_15) test beams. 
Quality of data was poor: front-end chips (running out of specs)
were randomly loosing hits, affecting cluster multiplicity.
In order to perform a measurement of depletion depth, (which is 
exactly based on cluster multiplicity), he developed a tecnique 
to verify whether a run was affected by the above mentioned loss
of hits. In positive case, he measured the rate of missing
hits in that run and corrected for. This procedure was verified 
with an ad hoc written MonteCarlo. 
As a result:
-not all the data can be used to obtain sensible results.
-after irradiation of e15, oxygenated sensors are fully depleted at 400-430 V.
-after irradiation of 5e14, oxygenated sensors are fully depleted at ~300 V.
-present data don't allow to see difference between oxygenated and 
 not oxygenated after irradiation of 5e14.      
     
Comment: data are in agreement with calculations performed in sensors group.
Unfortunately, data quality did not allow to test the validity
of the model used to perform these calculations (for example: measurement
of charge trapping as we did for not oxigenated ST2 sensors).  


     Modules studies              Attilio Andreazza
     ---------------              -----------------
Analysed data of FE-B flex modules taken in full MCC mode
in May and July 1999 (LBL FEB flex IZM bumps) and 
           July 2000 (Bonn FEB flex IZM bumps) and
tried to cross check with measurements in laboratory.
As already reported (June meeting), this year data 
show that bad TOT setting  gave reduced efficiency. 
Neverthless, seen an effect present also in M2 module:
found large chip to chip variation in 
the on-time efficiency, due to late hits.
Laboratory tests on the BONN flex module
-did not show a significant difference in time-walk
-showed a timing difference, but not enough to explain the effect.
Still open the question if this effect comes from FE chips or MCC or flex ...

Comment: 
Some of the results found could better be studied in lab, then
more tests and characterization should be done in lab before the test beams,
in order to optimize the use of the beam.
 
     Modules studies              Chiara Meroni
     ---------------              -------------
Analysed data of flex modules 
FH_Ge2 and FH_Ge3 (Genova, Alenia Bumps and thinned electronic FE_B chips)
taken in May (run 9252-9295)  and June 2000 (run 9393-9415  only FH_Ge3).
Studying the on-time efficiency for both modules read in transparent mode 
some chips showed an effect that can be explained only
as a jump of the "true" LVL1 (mainly a bit lost in the LVL1 word, 
inducing a jump from LVL1 6 to LVL1 4). 
If a correction for this effect is applied the ontime efficiency is
recovered to be >95% in most cases.
(To exclude external sources, checked that the corrisponding distributions 
for the single chip assembly taking data at the same time were normal.) 
A much worse situation was found for both modules operated in full MCC mode.
In that case the LVL1 distribution doesn't show any peak.

Comment: 
Problem could be due to both FE chips and MCC operating out of specs.
Anyway, this problem should be looked for when testing the new electronics.


     Updates on resolution studies                    Tommaso Lari
     -----------------------------                    ------------
Has completed a detailed study of spatial resolution vs. angle,
measuring the :
- resolution in a magnetic field
- resolution of oxigenated prototype 2 sensors after irradiation.
He applied a severe chi2 cut on tracks, in order to improve telescope 
resolution from 6 um to 4.5 um, keeping ~ 20% of the statistics.
We have now a clear picture of the behaviour of resolution as a function of:
- the sensor designs (ST1, ST2, SSG, SSG1b, Prot.2)
- irradiation
- thickness  
- magnetic field
as well as a coherent interpretation of the results.
      

     Updates on MCMD analysis                       Cristof Linder
     ------------------------                       --------------
Shows occupancy and resolution at 0 deg. of MCMD data taken in May 2000.


     Simulation of Lorentz angle                    Dirk Lipka
     ---------------------------                    ----------
Has written a simulation to evaluate the Lorentz angle.
His results confirm the measurements done in Milano and agree with
the simulation developed by Tommaso and Mario: 
the contribution of holes is small, the shifts in coordinate 
depend on the threshold.


     Priorities for 2001                                   all
     -------------------                                    
Next year test beams will start very late : at the end of June and will last
till end of October, with 2 weeks of 25 ns beam.
Major priority is to test the rad-hard electronics (FED2,DSM). 
A detailed program will be defined when the new electronics will be available.