2nCor Equipment

Detectors

PMTs

http://www.hamamatsu.com/resources/pdf/etd/R580_TPMH1100E.pdf

DAQ electronics

Signal Processing

Discriminator

CAEN N841

The pulse forming stage of the discriminator produces an output pulse whose width is adjustable in a range from 5 ns to 40 ns. Each channel can work both in Updating and Non-Updating mode according to on-board jumpers position. The discriminator thresholds are individually settable in a range from -1 mV to -255 mV (1 mV step), via an 8-bit DAC. The minimum detectable signal is -5 mV. The back panel houses VETO and TEST inputs, the OR output and the Current Sum output, which generates a current proportional to the input multiplicity, i. e. to the number of channels over threshold, at a rate of -1.0 mA per hit (-50 mV per hit into a 50 Ohm load) ±20%.

File:CAEN N841 Manual.pdf

LED output pulse width [arb. units]	Pulse width seen by the oscscope [ns]
10	6.3
20	6.6
40	7.1
60	7.6
90	8.5
120	9.5
160	12.0
190	15.1
230	24.8
250	43.5

NIM-ECL converter

Phillips Model 726

File:Phillip 726 Nim2ECL.pdf

TDC

Detector name convention

BLUT = Beam Left Upstream Top pmt

3/19/15

TDC channel Map (Thursday)

Detector	Angle	TDC channel	NIM-ECL channel	Patch Pannel #	ROOT vaiable
BLUT	135	TDC 16	in B ch 0	223A6	evt.TDC[16]
BLUB	135	TDC 17	in B ch 1	223A7	evt.TDC[17]
BRT	270	TDC 24	in A ch 0	223A14	evt.TDC[24]
BRB	270	TDC 25	in A ch 1	223A15	evt.TDC[25]
BLDT	45	TDC 26	in A ch 2	223A16	evt.TDC[26]
BLDB	45	TDC 27	in A ch 3	223A17	evt.TDC[27]
Trig Delay		TDC 30	in A ch 6		evt.TDC[30]
Photon flux monitor	90	TDC 29	in A ch 5	223A10	evt.TDC[29]

3/24/15

TDC channel Map 3/24/15

Detector	Angle	Single hit TDC channel	LED channel	NIM-ECL channel	Patch Pannel #	ROOT vaiable	MultiHit TDC channel
1 top (BRT)	270	24	0	in A ch 0	223A5	evt.TDC[24]	8
1 bottom (BRB)	270	25	1	in A ch 1	223A6	evt.TDC[25]	9
2 top BLDT	45	16	2	in B ch 0	223A7	evt.TDC[16]	0
2 bottom BLDB	45	17	3	in B ch 1	223A8	evt.TDC[17]	1
3 top	60	26	4	in A ch 2	223A9	evt.TDC[26]	10
3 bottom	60	27	5	in A ch 3	223A10	evt.TDC[27]
4 top BLUT	135	18	6	in B ch 2	223A11	evt.TDC[18]
4 bottom BLUB	135	19	7	in B ch 3	223A12	evt.TDC[19]
5 upstream	135	20	10	in B ch 4	223A15	evt.TDC[20]
5 downstream	135	21	11	in B ch 5	223A16	evt.TDC[21]
6 upstream	135	30	12	in A ch 6	223A17	evt.TDC[30]
6 downstream	135	31	13	in A ch 7	223A18	evt.TDC[31]
e+ spect		29	9	in A ch 5	223A14	evt.TDC[29]
Trig Delay		22	14	in B ch 6		evt.TDC[22]

TDC calibration

03/25/15

Multi hit TDC timing

Wiring Work

• 3/25/2015
  • Sean and Glen examined all of the signals from detectors 1 through 6
  • We used the signal from the LEMO cables that go directly into the discriminator
  • We also used the scope's Acquire->Average option and set the average to 512; This allowed for a more reliable comparison between signals
    • Note that the threshold can be adjusted and that the average will be biased toward smaller pulse heights if there is a lot of noise
  • Found an RG-62 cable connected between the bottom PMT of Det 3 and the patch panel A10
    • Replaced with RG-58 cable
  • A10 cable also found to be RG-58 from the experiment room to the counting room; Signal on 3B was degraded in the control room
    • Changed to A19 (RG-223 the whole length) and the signal looked similar to the others
  • Found that detector 5 top and bottom both were small and have the ~12 ns ringing
    • Increased voltage to 1500V
    • The non-extending gates from the discriminator will help with this
    • Recommend a gate width of 20 to 25 ns from the discriminator to eliminate double pulsing from ringing on Det 5
    • Should not matter for other detectors
    • Will also not affect high energy neutrons since 6 MeV neutrons are 30 ns ToF at 1 meter
  • When testing was complete, verified that all cables are associated with the appropriate detector
  • Top/Bottom, Upstream/Downstream should not have been reversed for any detectors in the process but that has not been confirmed; this should be correctable in software

Software

Ntuple maker

To make the Tree containing the TDC, QDC, and PDC data run the following command

source ~/CODA/setup

/home/daq/CODA/CODAreader/ROOT_V5.30/v775v792v785/evio2nt -fr8735.dat >/dev/null

rename the output file to a root file

mv r8735 r8735.root

root -l r8735.root

to draw a histogram for TDC channel 16

DAQ->Draw("evt.TDC[17]>>(4096,0,4096)");

for the multihit TDC data taken with daq2

CODA/CODAreader/ROOT_V5.30/R1DC/evio2nt -fr4516.dat > /dev/null

R1DC->Draw("(evt.TDC1190[1][3])");

R1DC->Draw("(evt.TDC1190[1][6]-evt.TDC1190[2][6])/10>>(4096,-4096,4096));

On 4/9/2015 the above should be 4000 channel = 400 ns

2nCor_44