• Veto plateauing instructions are here



• Results of Sep. 25, 2004 plateau:
• Hycal set to center position.
• Beam current = 5nA.
• Radiator B and target 5% Pb in place.
• Thresholds set to 100mV
• Plots for Left Top, Left Bottom, and Right Top.



• Results of Oct. 3, 2004 plateau:



• Specifications for plateau of top of HYCAL:
• Beam current = 80pA.
• Radiator = D (1x10^-5)
• Target = 5% Pb.
• Plots for beam on top of HYCAL:

Threshold=30mV	Left Top	Left Bottom	Right Top	Right Bottom
Threshold=50mV	Left Top	Left Bottom	Right Top	Right Bottom
Threshold=75mV	Left Top	Left Bottom	Right Top	Right Bottom




• Specifications for plateau of center of HYCAL:
• Beam current = 2nA.
• Radiator = B (1x10^-4)
• Target = 0.5% Be.
• Plots for beam on center of HYCAL:

Threshold=30mV	Left Top	Left Bottom	Right Top	Right Bottom
Threshold=50mV	Left Top	Left Bottom	Right Top	Right Bottom
Threshold=75mV	Left Top	Left Bottom	Right Top	Right Bottom




• Specifications for plateau of bottom of HYCAL:
• Beam current = 80pA.
• Radiator = D (1x10^-5)
• Target = 5% Pb.
• Plots for beam on bottom of HYCAL:

Threshold=30mV	Left Top	Left Bottom	Right Top	Right Bottom
Threshold=50mV	Left Top	Left Bottom	Right Top	Right Bottom
Threshold=75mV	Left Top	Left Bottom	Right Top	Right Bottom




• HV settings for 50mV threshold picked by M. Wood



• Analysis of run 4309

This run was taken to tune up the veto counter analysis. The goal was to measure e+e- pairs with the veto and HYCAL. Here are some pertinent information:

• Target = 5% Pb
• Trigger = single strip of hycal
• Tagger T-counter range = 1 -61
• PS magentic field = 1.5kG
• Radiator = B
• Beam current = 5nA

ADC spectra

Top Left	1	2	3	4	5	6
Bottom Left	1	2	3	4	5	6
Top Right	1	2	3	4	5	6
Bottom Right	1	2	3	4	5	6

TDC spectra

Top Left	1	2	3	4	5	6
Bottom Left	1	2	3	4	5	6
Top Right	1	2	3	4	5	6
Bottom Right	1	2	3	4	5	6




• Analysis of run 4285

This run was taken to measure the y-position dependence of the veto counters. The HYCAL was placed with the beam on the ultimate or penultimate row of PbW04. The x-position of HYCAL was 0.0. During the run , HYCAL was moved down so the beam moved up in effect. Here are some pertinent information:

• Target = 5% Pb
• Trigger = single strip of hycal
• Tagger T-counter range = 1 -61
• PS magentic field = 1.5kG
• Radiator = D
• Beam current = 80pA

Below are plots of TDC difference for related top and bottom veto pmts versus cluster y-position from the HYCALCLUSTER bank. The timing has NOT been calibrated. The numbering scheme for the veto counters is 1 is closest to the beampipe, and 6 is farthest. Also, I made a plot of the HYCAL cluster x versus y positions.

HYCAL x vs y



Left Counters	1	2	3	4	5	6
Right Counters	1	2	3	4	5	6

The statistics die out for counters #6, but the trend is apparent. There is some extra noise in the counters #1. This could be due to fact that the beam was directly on these counters or that the center hole cut-outs are causing some wierd reflections. These are just guesses.

Here are the Left and Right time difference (Top-Bottom) versus HYCAL cluster y-position plots for the 12 counters after the TDCs were calibrated. The calibrations were done with respect to the HYCAL&MOR trigger TDCs 1 and 2.