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File:Comp time 8857 4481.png

2015-03-26T21:17:59Z

Stave:

Analysis 03-26-2015

2015-03-26T21:17:39Z

Stave: Created page with "=TDC comparison= * Comparison of run 8857 (single hit TDC) and 4481 (multihit TDC) for the same beam and electronic settings: ** 500 ps pulse width, 800 mA peak current, 200 Hz …"

=TDC comparison=

* Comparison of run 8857 (single hit TDC) and 4481 (multihit TDC) for the same beam and electronic settings:
** 500 ps pulse width, 800 mA peak current, 200 Hz rep. rate, DU cyl. target in, 10 mV LED (all), 40 ns LED (all), 1" Al radiator, 3/4" Pb collimator/Pb shielding wall on the accelerator side. Slits are at 350. Pb brick is removed.
* Normalized 4481 to the same number of beam bursts
* The single- and multi-hit TDC plots look very similar
* Note that Det 2T was not in the ROOT tree for 4481 at the time of analysis.

[[File:comp_time_8857_4481.png | 200 px]]

2nCor 44

2015-03-26T21:14:22Z

Stave: /* Analysis */

=Physics=
A large body of experimental work has established the strong kinematical correlation between fission fragments and fission neutrons. Here, we investigate the potential for strong two neutron correlations arising from the nearly back-to-back nature of the two fission fragments which emit these neutrons in the photo-fission process. In initial measurements, a pulsed electron linear accelerator was used to generate bremsstrahlung photons which impinged upon an actinide target, and the energy and opening angle distributions of coincident neutrons was measured using a large acceptance neutron detector array. A comprehensive set of measurements of two neutron correlations in the photo-fission of actinides is expected to shed light on several fundamental aspects of the fission process including the multiplicity distributions associated with the light and heavy fission fragments, the nuclear temperatures of the fission fragments, and the mass distribution of the fission fragments as a function of energy released. In addition to these measurements providing important nuclear data, the unique kinematics of fission and the resulting two neutron correlations have the potential to be the basis for a new tool for the detection of fissionable materials. A key technical challenge of this program arises from the need to perform coincidence measurements with a low duty factor, pulsed electron accelerator. This has motivated the construction of a large acceptance neutron detector array, and the development of data analysis techniques to directly measure uncorrelated two neutron backgrounds.

=Equipment=

[[2nCor_Equipment]]

=Run Plan=

[[03-19-2015]]

[[03-24-2015]]

[[03-26-2015]]

=Analysis=
[[Analysis_03-26-2015]]

Go back [[Neutron_Corr]]

2nCor 44

2015-03-26T21:14:06Z

Stave: /* Run Plan */

2nCor 44

2015-03-26T21:13:56Z

Stave: /* Run Plan */

2nCor Equipment

2015-03-25T21:38:02Z

Stave: /* Wiring Work */

=Detectors=
==PMTs==

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

==Scintillators==

==e+e- spectrometer==

=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]]

===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)
{| border="1"
| 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
{| border="1"
| Detector || Angle ||TDC channel ||LED channel || NIM-ECL channel|| Patch Pannel # || ROOT vaiable
|-
| 1 top (BRT)|| 270|| 24|| 0 ||in A ch 0 ||223A5|| evt.TDC[24]
|-
| 1 bottom (BRB)|| 270|| 25|| 1 ||in A ch 1 ||223A6|| evt.TDC[25]
|-
| 2 top BLDT || 45 ||16 || 2|| in B ch 0 || 223A7 || evt.TDC[16]
|-
| 2 bottom BLDB || 45 || 17 || 3|| in B ch 1|| 223A8|| evt.TDC[17]
|-
| 3 top || 60 ||26 ||4 || in A ch 2 || 223A9 || evt.TDC[26]
|-
| 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]]

==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

==ADC==

[[2nCor_44]]

=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)");

2nCor Equipment

2015-03-25T21:33:11Z

Stave: /* Wiring Work */

=Detectors=
==PMTs==

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

==Scintillators==

==e+e- spectrometer==

=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]]

===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)
{| border="1"
| 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
{| border="1"
| Detector || Angle ||TDC channel ||LED channel || NIM-ECL channel|| Patch Pannel # || ROOT vaiable
|-
| 1 top (BRT)|| 270|| 24|| 0 ||in A ch 0 ||223A5|| evt.TDC[24]
|-
| 1 bottom (BRB)|| 270|| 25|| 1 ||in A ch 1 ||223A6|| evt.TDC[25]
|-
| 2 top BLDT || 45 ||16 || 2|| in B ch 0 || 223A7 || evt.TDC[16]
|-
| 2 bottom BLDB || 45 || 17 || 3|| in B ch 1|| 223A8|| evt.TDC[17]
|-
| 3 top || 60 ||26 ||4 || in A ch 2 || 223A9 || evt.TDC[26]
|-
| 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]]

==Wiring Work==

* 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

==ADC==

[[2nCor_44]]

=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)");

2nCor Equipment

2015-03-25T21:23:00Z

Stave: /* ADC */