2n Neutron signal attenuation

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Cf-252 source attenuation test

Cf-252 source was used to define the attenuation of a signal produced by neutrons in plastic scintillator. Cf-252 source was placed in different positions along the detector surface shielded with 2" of lead and counting rate of the two PMTs was observed via dual counter ORTEC 778. Cf-252 source was surrounded by borated poly to provide collimation of about 5 cm in diameter.

File:Data attenuation.pdf

Would you add to the plot the sum of the rate from each end of the PMT.

In order to get it on the same scale you could divide by 2 or use a scale on the right side of the graph

Data with the counting rate from each tube added together.


Detector E(1,2) neutron signal attenuation data sheet:

File:Detector E data.pdf

Det E pic.jpg

Detector M(1,2) neutron signal attenuation data sheet:

File:Detector M data.pdf

Det M pic.jpg

Detector F(1,2) neutron signal attenuation data sheet:

File:Detector F data.pdf

Det F pic.jpg

Detector G(1,2) neutron signal attenuation data sheet:

File:Detector G data.pdf

Det G pic.jpg

Detector H(1,2) neutron signal attenuation data sheet:

File:Detector H data.pdf

Det H pic.jpg

Detector K(1,2) neutron signal attenuation data sheet:

File:Detector K data.pdf

Det K pic.jpg

Detector I(1,2) neutron signal attenuation data sheet:

File:Detector I data.pdf

Det I pic.jpg

Na-22 source timing rest

Raw spectra

BKG timing.jpg

Left close timing.jpg

Middle timing.jpg

Right close timing.jpg

Normalized and BKG subtracted data

For all the timing spectra it was calculated K1(left)-K2(right).

The source is close to the left PMT (13.86 cm away):

Leftest minus bkg.png

The source is a bit further from the left PMT (17.64 cm away):

Left minus bkg.png

The source is at the center of the detector:

Center minus bkg.png

The source is close to the right PMT (13.86 cm away):

Rightest minus bkg.png

Calibration curve

Finally, using the mean values of the fitted Na-22 peaks the calibration curve can be plotted:

Calibration line.jpg