Some photos of the elements in the last part of the beam line
during Takechi run.

After the chamber that includes the F11 plastic detector
there are 2 GSI-MUSIC chambers.

In between the MUSIC chambers there is a sample changer 
with 2 Carbon targets of 6mm and 3mm thickness and also
an empty position.

After the 2nd MUSIC there is a plastic detector for testing 
(could be removed at any time)

Afterwards there is the degrader mounted on a separate table.
In the same table there is a 10cm thick lead wall
to protect AIDA during Takechi run.

Mounted on the shielding are from the beam side the top and bottom 
plastic veto detectors.

On the back side the Si detector is mounted.

The hole in the shielding is covered with
a 2cm thick Al plate to protect AIDA during Takechi run. 

Behind AIDA there is a thin plastic detector
to veto the passing through particles.

Beam tuning in BigRIPS

At 19:00 access to Exp. Area was closed and the tuning
of BigRips started.

Unfortunately the 252Cf was left on the table close
to the stairs and cannot be removed until 23:00.

We did a background measurement
Start: 19:00
Stop: 22:18

File: 161104_2218_BeamTuning.root

In the attached figure 1 one can see a plot of the rate
(neutrons/10s) in the BRIKEN detector during this time
The rate was at high as 150n/s during this period.
We estimate that the influence of the 252Cf source is about 15n/s
(corresponds to the lowest rates)

Also attached are pictures of the Top and Bottom plastic veto detectors
mounted just above and below the hole in the shielding.
Interestingly the bottom sees less counts at high energy
and this could be related to the 10cm lead wall raised
before the degrader to protect AIDA that covers only partially 
the top detector.

Also attached is the neutron spectrum for the different rings superposed.
(ROOT color code)

Energy calibration for clovers, 152Eu



The Eu source positioned in the center roughly. 
File name: 161103_1426_152Eu.root

Energy Calibration: See attached pdf

Detector Slope Offset
V2A7C1 0.00155643 0.0842245
V2A7C2 0.000658962 0.78685
V2A7C3 0.00153391 1.198
V2A7C4 0.00157933 0.483094
V2A7C5 0.000704268 0.31553
V2A7C6 NOT THERE
V2A7C7 0.00066837 0.465225
V2A7C8 0.000695872 0.678058





> Energy calibration for clovers, 152Eu
> 
> 
> 
> The Eu source positioned in the center roughly. 
> File name: 161103_1426_152Eu.root

Measurement over night with a 152Eu source inside

Start: 22:48 (03/11/2016)
Stop: 08:26

File: 161104_0826_152Eu.root

Neutron background rate: 0.82 n/s

Geant4 BRIKEN Neutron efficiency calculations as a function of neutron energy and for some spectra: Ga84-vandle, Br88-endf71, Rb94-endf71, Rb95-endf71, I137-endf71, Cf252-MCNPX
  

Calculations for the current BRIKEN detector configuration:

Hybrid mode, 140 counters, assembled in July16.


Summary of files:

BRIKEN_hybrid140.svg  ---> Scheme for the current tube configuration. 

BRIKEN_hybrid140_efficiency.xlsx  ---> Sheet with results of the calculations.

Efficiency_vs_Energy_HybridConf_140b.svg ---> Plot of the neutron efficiency by Ring (see BRIKEN_hybrid140.svg) and total.

We used the laser to align the degrader (see attached photos)

According to the LISE calculation, equivalent effective thickness for 6 mm of Carbon target is 4.5 mm thick Aluminum.

Therefore, we've set the degrader system as follow:

Background measurement for threshold determination



Started at 14:45
Stopped: 16:35

Root file: 161103_1635_bck.root

Check of BRIKEN calibration and thresholds

Source more or less at the center

Online File: 161103_1319_252Cf.root

Start of commissioning preparation


Working directory:
/data/1611Commissioning/161031Preparation/


DACQ configuration file:
161103Conf_BrikenFull.xlsx

Efficiency calibration

File "cloversEff.ods" and "cloversEff.xls" contains the experimental efficiency from different measurements
during July and October
(G7 broke before Eu-152 measurement). We can assume the efficiency didn't change from July measurements to
October measurements. 

Efficiency calibration for the G7 clover (data acquired in July).
The attached plots show the parameters for the Jackel function (E[i]=Energy) using the points of a 152Eu source.

Roger





> Efficiency calibration
> 
> File "cloversEff.ods" and "cloversEff.xls" contains the experimental efficiency from different measurements
> during July and October
> (G7 broke before Eu-152 measurement). We can assume the efficiency didn't change from July measurements to
> October measurements. 

Efficiency calibration for the D4 clover (data acquired in October).
The attached plots show the parameters for the Jackel function (E[i]=Energy) using the points of 152Eu, 60Co and 137Cs sources.

Roger





> Efficiency calibration
> 
> File "cloversEff.ods" and "cloversEff.xls" contains the experimental efficiency from different measurements
> during July and October
> (G7 broke before Eu-152 measurement). We can assume the efficiency didn't change from July measurements to
> October measurements. 

Attached the updated excel file. In the first sheet there is the calculator to calculate the efficiency from an given energy.

The Jackel function used is:
Double_t fun=TMath::Exp((par[0]+par[1]*TMath::Log(x[0])+par[2]*TMath::Log(x[0])*TMath::Log(x[0]))*2/TMath::Pi()*
(TMath::ATan(TMath::Exp(par[3]+par[4]*TMath::Log(x[0])+par[5]*TMath::Log(x[0])*TMath::Log(x[0]))))-25.);




> Efficiency calibration
> 
> File "cloversEff.ods" and "cloversEff.xls" contains the experimental efficiency from different measurements
> during July and October
> (G7 broke before Eu-152 measurement). We can assume the efficiency didn't change from July measurements to
> October measurements. 

From the 252Cf data.

Paper logbook for July-2016
For correct visualization, 
please download it.

Paper logbook for October-2016
For correct visualization, 
please download it.

dE detector is mounted onto the back side of the shielding (attached photo: dE_position.JPG)

The detector consists of 26 strips. In this setup, the detector is devided into 2 parts corresponding to 2 readout channels. Each part consists of 13 strips joint together.

Output signal from a high gain channel of preamplifier with 137Cs source is shown in attachment 137CsTest_ac.JPG.;

The white noise is about 2 mV for high gain mode.

We will switch to low gain mode during the experiment.

* note:there is a 200 mV offset due to the characteristic of the preamplifier (see attachment dc.JPG)

... and sashimi (see photo)

The detectors (BRIKEN tubes, CLOVER, VETO detectors, AIDA) 
are mounted, tested and ready for November commissioning,
except beam detectors a Plastic TOF and a Si detector which
will be attached to the PE shielding.
DACQs (BRIKEN, AIDA) are running. The synchronization monitoring
program which was working in June, for some reason is not functioning
properly now and is being worked on (desirable but not required).
The data merger and near-line analysis programs are being worked on.

Installation of BRIKEN PE shielding for beam
related neutrons

The missing metallic pieces needed to mount
the forward PE shielding finally arrive and
we mount it with help of the crane.

The shielding (4 PE slabs + 1Cd-PE slab) has attached 
the support for VETO detectors on the beam side
and for and additional ancillary detector
a large Si detector on the BRIKEN side.
See attached photos.

The distance between shielding and BRIKEN is 40 cm.

Friday, October 14, 2016 21:50
AIDA and BRIKEN-CLOVER run with a common clock.

After installing the shielding and checking electronics
(See next entry)

252Cf source 7.5cm from the center.
AIDA nose aligned with the edge of the clovers hole.

start: 21:50 run number: BRIKEN:15 AIDA:0 
stop : 22:18 run number: BRIKEN:16 AIDA:9

BRIKEN dlt file:252CfWithAida75mmcenter_15 to _16
AIDA file: aidas1:/TapeDate/Sept2016/R41_0 to _9 

Online analyzed data around 30%
Online spec: 252CfWithAida75mmcenter_15_16.root
Configuration file attached.

As previously recorded (81), on Thur Oct 13th, A NIM crate failure caused preamp power loss to the HPGe's. While D4 recovered with nominally the same resolution as before. G7 would not recieve power to the preamps without an alarm from the NIM crate.

It was determined that there was a short along the lines of +12V and Ground , -12V and Ground, and between +-12V.

After removing the Red preamp ribbon cable, the remaining channels (K,G,B) were able to be powered on and found to have a nice resolution of near ~2.3 keV for 661 (137Cs).

During the course of testing, the preamp power distribution box (supplied from ORNL) was seen to have a fault in the +12V light and supply. This was seen by placing this supply in a new NIM bin and seeing that it would also not properly supply preamp power to clover D4 (which had recovered fully).

The consistency in this fault is seen as cause to be suspicious of this preamp power supply. It has been replaced by putting two ORTEC TSA's into a seperate NIM bin and using the standard power supply for D4 and G7.

There was no appreciable effect on noise in any other detector.

Change of main power line for MPOD and CLOVER preamp


Because the incident yesterday with the NIM crate,
we try to separate the CLOVER from the rest of 
the equipment.

So we put the MPOD, which powers the CLOVER but also
the 3He tubes and the VETO detectors, and the preamp
power supply in a different line.

We check if this has an impact on the noise in either
CLOVER or 3He tubes.

We measure with the 137Cs-60Co source:
File: 161014_1241_137Cs60Co.root

After inspecting the spectra we conclude that the impact
is not appreciable.

See figures 

662keV resolution:
D4Black: 3.16keV
D4Red: 2.49keV
D4Green: 3.57keV
D4Blue: 3.40keV

New configuration file: 
161014Conf_BrikenFull.xlsx