j.nima.2018.09.076 Errors?

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Joe Gayo
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j.nima.2018.09.076 Errors?

Post by Joe Gayo »

A study on neutron emission from a cylindrical inertial electrostatic confinement device
Authors: N.Buzarbaruah, S.R.Mohanty, E.Hotta
Nuclear Inst. and Methods in Physics Research, A Volume 911, 11 December 2018, Pages 66-73
https://doi.org/10.1016/j.nima.2018.09.076

A less than a stellar research paper, but I wanted the community's comments on Figure 6. My interpretation is that there was a thermal hotspot on the viewport and that's what formed the closely packed bubbles. The bubbles also all seem fairly large in size (but potentially OK).
1-s2.0-S0168900218312208-gr6.jpg
Also in Figure 7, they claim the He-3 tube pulse height spectrum confirms 2.45MeV neutrons, but my understanding is that the 764keV peak is from capturing thermal neutrons and contains no energy information from the original neutron. Furthermore, the number of counts seems very low for a device producing 6E6 n/sec.
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Andrew Seltzman
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Re: j.nima.2018.09.076 Errors?

Post by Andrew Seltzman »

Bubbles from heating are small and well localized:
viewtopic.php?t=11056

This is more likely non homogeneous response of the jell. I would trust BTI to have compensated for this when binning/calibrating their dosimeter sensitivities, we have seen this effect before.
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Richard Hull
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Re: j.nima.2018.09.076 Errors?

Post by Richard Hull »

Wish I could read the whole paper. Pay to play is a no-no for me. They could have had the detector at a grid beam point If so, I would never tape it to a window where heat was. I always put my bubble detector below the chamber and a few centimeters way with a small fan making sure thermal air currents from the hot fusor shell would not affect the BTI bubble count. I do find the bubble count far too low. I do not know the binning or the length of exposure of the operating point for the specific image. This may have been in the paper, however.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
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