IPUs of CTF3: Formulae for position and current calculation

 

 

Position calculation (alignment errors not included)

 

 

 

AH, BH, AV, BV - pick-up slopes and offsets for horizontal and vertical planes measured on a lab test bench, they are listed in the table below

 

DHCAL+, DHCAL-, DVCAL+, DVCAL-, SCAL+, SCAL - - signal amplitudes from the calibration with the Calibration Current Generator pulses; the values are from both, positive and negative calibration

 

DH, DV, S - signal amplitude measured

 

Error [mm] (0.1 + 1 %) for positions < 5 mm

 

 

Beam current calculation

 

 

Calibration current ICAL = 0.3 A 0.1%, 1.5 or 150 ms

 

 

Pick-Up coefficients

 

BPM

AH

BH

AV

BV

402

15.23

-0.08

15.27

0.10

502

15.34

-0.03

15.33

0.04

590

 

 

 

 

690

15.14

0.02

15.28

0.06

790

15.34

0.08

15.25

0.03

825

 

 

 

 

890

15.04

-0.07

15.02

0.16

 

The coefficients are believed to be measured with the error not larger than some 20 mm

 

 

Amplifier gains

 

Gain

GD

[V/V]

GS

[V/V]

Low gain (beam current < 10 A)

5.8

1.85

3.1

High gain (beam current < 1 A)

58

18.5

3.1

 

The exact gain values are measured during the online calibration and they are expected to not differ by more than 2 % from the table values.

 

 

 

(c) M.Gasior, AB/BDI/PI. Last updated: 22/10/03.