Analysis of Endstation A setup

Josef Uher

Quartz bar Start counter

Configuration with ADC gives possibility to correct measured time on pulse height off-line.

=> better control than in case of CFD

Quartz bar start counter

4 pad MCP TDC

ADC

LeadingEdge Disc.

PiLas laser

Start Counter – resolution vs. light intensity

Before ADC correction After ADC correction

Raw TDC/ADC ADC correction ADC slices Resolution vs.Light intensity

Analysis procedure:

Start Counter – resolution vs. light intensity

Time resolution vs. number of electrons, Quartz bar start counterGate set to 30 ns (measurement from 12-16-2004)

10

100

1000

0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00

ADC signal [photoelectrons]

Sig

ma

[ps]

Sigma (FWHM) - new data (narrow gate)

Narrower sigma - old data (wide gate)

1 over square root

~50 ps

~50 photons

Each point is sigma obtained from double Gaussian fit of TDC spectrum.

Quartz start counter in multiphoton mode

Pad

0P

ad

1P

ad

2P

ad

3

Light intensity: from 200 to 700 photons

=44 ps

=29.5 ps

=76 ps

=28.5 ps

0 1

2 3

The laser si not 100% centered

TDC spectrum Raw ADC/TDC Corrected ADC/TDC

Prototype

Slot tests

Slot 2 Slot 3 Slot 4

Slot 5 Slot 6

All slots tested with the same set of Philips TDCs

Tested 320 pads in 5 slots. 301 pads were OK.

56 pads OK 60 pads OK 58 pads OK

64 pads OK 62 pads OK

Note: “pad” includes MCP, amplifier and CFD

Timing resolutions in single photon mode

  Best [ps] Worst [ps] Average [ps] Median [ps]

Slot 2 181 393 253 230

Slot 3 194 419 250 237

Slot 4 157 416 259 264

Slot 5 164 385 221 211

Slot 6 168 353 228 211

Table of resolutions

Table of hit probabilitiesPilas frequency 1kHzSlot Hit probability* Multiple hits** DAQ [Hz]

2 1.8% 1 99

3 1.0% 2 109

4 5.8% 8 102

5 3.5% 4 102

6 0.6% 1 102

**number of pads hit by photons per event

MA

*hit probability for single pad

MC

PM

CP

MC

PM

CP

MA PMT connected to SLAC ADCs and Phillips TDSs

Phillips(common start)

SLAC(common stop)

Log

scale

Log

scale

Log

scale

Majority ofevents

System stability

System stability

TDC spectrum (the whole run)

Peak position asa function of time

The aim is to determine stability of channel delay calibrations over time. Discover systematic effects.

10 hours

Counts [-]

2.6

2 c

ou

nts

~0

.34

Online monitoring

Example of online monitoring histograms

Hodoscope window

Cherenkov ring window

Histograms in the window:

•horizontal fingers•horizontal hit multiplicity•vertical fingers•vertical hit multiplicity•horizontal profile•vertical profile•raw hit map•corrected hit map

Data of any module in the system can be visualized online.

(including start counters, MAs and MCPs in the prototype and other)

(+ Timing windows)

Software status

What we need to see online:

• Hodoscope• 2D beam position histogram• x and y profiles• hit multiplicity

• Startcounters timing

• Preview of Cherenkov rings

(The first version of software documentation is ready.)