Index of /experiment/E94-107/Optics

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	README	03-Jun-2005 15:45	3.2K
	septum-plan-2005-v1	03-Jun-2005 15:45	3.2K

Septum Commissioning Plan
-------------------------

Goal: Establish that the beam quality is acceptable by checking the size
      of an elastic peak from a single sieve hole on the focal-plane.
      Next take high quality optics data to improve the present septum
      optics database which is presently only good to the 1.5E-4 level.

Intial Conditions: 	Beam Energy 1850 GeV
			Septa at 6 Degrees 
			Raster Off
			Thin Sieve Slit In
                        No Target

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Once beam has been sent back to the Hall, request 5uA and do a harp
scan to make sure the beam size at the second harp 1H04B is still
apprx. 50 um in width.  Fast feedbacks MUST be on and working.

Verify that SLI and OTR energy devices are giving good values.  Take OTR out 
(both target and arc!) before taking optics data.

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Before beginning a measurement in any kinematics, the shift workers must log
the Hall main screen and the magnet strip tool!  Waiting for the dipole 
magnets to settle is one of the key parts taking good optics data.

Start with  delta=0% with the spectrometers at 1850 MeV/c.

Take two 500k data runs with this setup for thick carbon, carbon thin, Ta, H20. 

   Once all this is done, we will proceed with collecting optics
   data.  All points should be done with 12C and Ta.  For simplicity
   the raster can be left OFF since we will only be using less than 5 uA. 

   Perform elastic delta scan with two runs at each point.  Each file 
   should have AT LEAST 500k.  Rates in both arm should be about equal, 
   but make sure to get AT LEAST 250k with each
   arm.  Also remember  to cycle the quadripoles when increasing momentum.  
   Quality of this test is very important.  Please check all runs with the analyzer.  
   (central momentums are for 12C elastic)

           (Momentum = 1.924 GeV for +4.0%) 
           (Momentum = 1.887 GeV for +2.0%) 
           (Momentum = 1.850 GeV for  0.0%) (one run with raster on w/12C and H20)
           (Momentum = 1.813 GeV for -2.0%) 
           (Momentum = 1.776 GeV for -4.0%)

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To check for the effects of cross talk between the HRS's and while 
the sieve is in, we should also:

(0) return left HRS to delta = 0 and take a run
(1) turn RHRS  septum off and take a run
(2) turn RHRS Q1 off and take a run
(3) turn RHRS Q1 50% positive and take a run
(4) turn RHRS Q1 100% positive and take a run
(5) return Q1 to negative and turn on septum and take a run

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Leaving the spectrometers in negative polarity, take an access and rotate the sieve 
slits to the out position.

Repeat delta scan.  Take data with the thin carbon foil and possibly with the Ta foil.
Again two runs with 500k each.

           (Momentum = 1.924 GeV for +4.0%) 
           (Momentum = 1.906 GeV for +3.0%)*  
           (Momentum = 1.887 GeV for +2.0%) 
           (Momentum = 1.867 GeV for +1.0%)*
           (Momentum = 1.850 GeV for  0.0%) (one run with raster on w/12C and H20)
           (Momentum = 1.832 GeV for -1.0%)*
           (Momentum = 1.813 GeV for -2.0%) 
           (Momentum = 1.795 GeV for -3.0%)*
           (Momentum = 1.776 GeV for -4.0%)

If we are short on time, the (*)'ed points could be left out, but we should really try to
get the data if we can.

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