22/09/2004 1

PM and shoebox tests

Hamamatsu 19 and 16 dynodes compared to

FEU 187 15 dynodes Jyväskylä’s shoebox (T0)

V0A

V0C

22/09/2004 2

Electronics for MIP measurements

FA

V0 counter

op

tical fi

bers

TDC1

PM

HT 30 ns

gate

QDC

THR1

5 m

anode

FI/FO

FI/FOTHR2

THR3

THR4

TDC2

TDC3

TDC4

start

25 m

25 m

17 p.e./MIPthr4

thr3

thr2

thr1

pedqdc

peddisc

22/09/2004 3

FEU

18

7 g

ain 18 14

21

20

19

15

22/09/2004 4

Hamamatsu and FEU 187 gain

19 dynodes

16 dynodes

15 dynodes

Hamamatsu

FEU 187

22/09/2004 5

Hamamatsu / FEU 187

17

16

15

MIP measurement at equal gain• 17 p.e. for the most probable charge• 12 pC / 60 mV • charge = MIP / 4 for Hamamatsu PMT• charge = MIP / 2 for Russian PMT• time (Ham.) = 1.5 time (FEU 187)• a threshold at 2 charge (98%) - MIP / 2 mV for Hamamatsu (30 mV) - 0 for FEU 187 Hamamatsu will be selected for V0

22/09/2004 6

time versus discriminator threshold

17 p.e.

2 > 0 mV

2 > 30 mVdynamics: 3 mV-3 V

MIP amplitude > 60 mVHam.

FEU 187

22/09/2004 7

MIP versus discriminator threshold

17 p.e.

Maximum efficiency

2 MIP efficiency

22/09/2004 8

H6153-70 = R5946 + HV divider (+)

PMT and divider in in a common cylinder• makes the mounting easy• simplifies the mechanics•

22/09/2004 9

Electronics for tests with the schoebox

A10/A25

V0 counter

op

tical fi

bers

TDC1

PM

HT 30 ns

gate

QDC

THR1

5 m

anode

FI/FOTHR2

THR3

THR4

TDC2

TDC3

TDC4

start

25 m

25 m

17 p.e./MIPthr4

thr3

thr2

thr1

pedqdc

peddisc

shoeboxA1

CFD

TDC4

thr

22/09/2004 10

Measurement with the shoebox

16 dynodes Hamamatsu tube• Charge distributions as a function of - high voltage: 1400, 1600, 1750, 1800, 2000, 2200 - amplification factor: 1, 10, 25• Time resolution with amplification 10 and threshold / constant

fraction discriminators as a function of - high voltage: 1400, 1600, 1800, 2000, 2200 Extraction of the time resolution values still to be carried out

22/09/2004 11

Charge distributions at 1400 V from 16 dynodes Hamamatsu PMT

Without shoebox

HT= 1400 V, A=1

HT= 1400 V, A=25HT= 1400 V, A=10

HT= 1400 V, A=1

22/09/2004 12

T0 schoebox as described in TDR

PM Anodesignal

100 ohms

50 ohms

50 ohms

G=3.2

G=3.2

To TRDwake-up

To T0 FEEthreshold disri.

and QDC

To T0 FEECFD

G=3.2

22/09/2004 13

V0 pulse treatment

shaperNINO

(0.1 – 2 pC) 2 ns

ORPM Anode

signal

100 ohms

50 ohms

50 ohms

G=3.2

G=3.2

Signal amplitude3 mV – 3 V

(5 mV – 5 V)

Signal amplitude3 mV – 3 V

(5 mV – 5 V)

Signal amplitude9.5 mV – 300 mV

(16 mV – 300 mV)

Signal amplitude30 mV – 1. V

(50 mV – 1. V)

To TRDwake-up

To V0 FEEthreshold disri.

To V0 FEEQDC

G=3.2

G=1

Signal charge0.6 pC - 600 pC(1 pC - 1000 pC)

Signal charge6 pC - >200 pC

(10 pC - >200 pC)

Signal charge6 pC - >200 pC

(10 pC - >200 pC)

22/09/2004 14

15/10/2004

CIU PCB prototype

22/09/2004 15

16/11/2004

Tests in progress

22/09/2004 16

Conclusion

Choice of the Hamamatsu PMT 16 dynodes• gain = 3 106 at 2000 V (FEU = 3 105)• charge resolution = MIP/4 (FEU = MIP/2)• time resolution (MIP = 17 p.e.) < 1 ns at 1750 V (FEU #

1.4 ns) Choice of the T0 shoebox with an amplification of 10• direct signal to QDC • amplified (clamped) signal to discriminator

22/09/2004 17

Quota

tion f

rom

Ham

am

ats

u

France

22/09/2004 18

V0 cost for 64 channels (R5946-70)label unit spare unit price total price

H6153-70 (R5946-70) 64 6 1500 105000

HV SY2527/A1733P 1/6 - 8812/2929 26386

VME 1 - 6000 6000

Electronics 64 2 70000

Mechanics PM + boxes 2 - 1000 2000

Scint. V0A/V0C (m2) 2 x .6 - 1500 1500

WLS F. V0A/V0C (m) 2 x 346 - 3.3 2284

Clear F. V0A/V0C (m) 2 x 3456 - 1.0 6912

Total in € 220082

Total in SF 330123

HV cab. V0A/V0C (m) 270 - 5.8 1566

HV con. V0A/V0C (448) - 4756

Sig. cab. V0A/V0C (m) 2 x 1600 - 2.0 6400

Sig. con. V0A/V0C (2 x 576) - 11136

Total in SF 353981

22/09/2004 19

Present programme Order of:• VME crate: 15/12/2004• 70 systems H6153-70 (PM5946-70 + HT divider): 15/12/2004 - delivery: 10 (06/2005), 20 (07/2005), 20 (08/2005), 20 (09/2005)• scintillator BC404: 15/12/2004• shifting fibers: 15/12/2004• optical fibers: 15/12/2004 Sector  ’’0’’:• available: 03/2005• tested: 04/2005• design review: 04/2005 Sectors ’’1’’ - ’’7’’ + V0C box + V0C fiber cables• available: 11/2005• tested: 12/2005 PM characterisation:• gain curves: 12/2005 V0C ready end of 2005 V0A ready in June 2006 Electronics R&D: follows the time-table (TDR)• CIU prototype tested: end 2004

22/09/2004 20

Hamamatsu mesh PMT performances (I)

22/09/2004 21

Spectral response

Hamamatsu

Hamamatsu / FEU 187

22/09/2004 22

Hamamatsu mesh PMT performances (II)

22/09/2004 23

Hamamatsu mesh PMT performances (III)

22/09/2004 24

Recommendation for the HV sign

1) The R5505-70 and the R5946-70 are for +HV operation.>> We usually recommend +HV operation for all of the Fine Mesh PMTs. The> reason is as follows:>> Basically, there is no difference in PMT itself between -HV model and> +HV model. When a fine mesh PMT is operated at -HV, it sometimes> generates large noises. This is due to discharge between electrodes> (former stages of dynodes), the bulb and supporting materials outside.> Fine mesh PMT has proximity configuration, the electrodes are set> close to the window and the bulb. When -HV is used, potential of these> electrodes become -HV. There could be large potential difference> somewhere around window. In case of +HV operation, as cathode is> grounded, there is less potential difference between electrodes, the> bulb and supporting materials. Therefore noise becomes less. We would> like to recommend +HV operation for all customers.

22/09/2004 25

1. Here is the anode dark current stability data of the R5946 (1.5«  Fine Mesh PMT). The horizontal axis is operating time and the vertical axis is the anode dark current recorded by ampere meter and recorder (10 mV = 100 nA). The upper data was measured at -HV operation and the lower one was measured at +HV operation. The PMT was supported by its socket, and there was nothing around the PMT bulbs. Spike noises appeared at -HV operation. However, when it was used at +HV operation, the noise became less.

22/09/2004 26

Waveform of the pulse

2. We checked the waveform of the R5505(1 inch Fine Mesh PMT) and the following is its data. Blue curve is at -HV operation and pink one is at +HV operation. Although the overshoot was rather seen at +HV, it's not so much.

Therefore, we would like to recommend +HV operation.

22/09/2004 27

Ham

am

ats

u /

FEU

18

7

com

pari

son

17

16

15 28

29

27

60 m

V pul

se