Search found 130 matches

by Bruce Meagher
Thu Feb 14, 2019 6:09 pm
Forum: Vacuum Technology (& FAQs)
Topic: Cleaning/Repairing Edwards E2M5
Replies: 20
Views: 1417

Re: Cleaning/Repairing Edwards E2M5

Before you disassemble your pump are your sure you don't have a leak around the BSP threads on the intake flange? I know I steered you to the inexpensive intake flange, and as I mentioned this cheap version does not have a proper o-ring seal. The BSP threads are straight making it a little more diff...
by Bruce Meagher
Thu Feb 07, 2019 7:13 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Construction of Neutron Grade Fusor
Replies: 45
Views: 3275

Re: Construction of Neutron Grade Fusor

Congratulations Enzo! It’s great seeing you working closely with your dad to create and run some cool science experiments. I believe you are the first person to use the GS Neutron detector to claim fusion. It seemed like you went through some issues, and it would be a good separate post to describe ...
by Bruce Meagher
Thu Feb 07, 2019 6:24 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Reaching Out
Replies: 1
Views: 213

Re: Reaching Out

Hi Jack,

I'm in San Diego and can meet up if you're willing to make the drive down from OC. PM or email me.

Bruce
by Bruce Meagher
Tue Jan 22, 2019 8:39 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Construction of Neutron Grade Fusor
Replies: 45
Views: 3275

Re: Construction of Neutron Grade Fusor

It’s great you’re continuing to gather data. From the video it would appear you are producing lots of neutrons, but running the test mentioned previously should help your case. My inverse square law comment was about the impact of moving the detector farther from the core, but as you noted it also a...
by Bruce Meagher
Mon Jan 21, 2019 5:11 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Construction of Neutron Grade Fusor
Replies: 45
Views: 3275

Re: Construction of Neutron Grade Fusor

Excellent job Enzo and dad! You guys have created a very nice setup. Couple comments: In the video when you were doing the unmoderated runs you sometimes drop the tube slightly behind the moderator. Leaving the moderator there will still present some thermal neutrons to the tube (explaining a few of...
by Bruce Meagher
Tue Jan 15, 2019 7:54 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: How to figure out the specs of old Rigaku scintillation tube probe?
Replies: 24
Views: 1890

Re: How to figure out the specs of old Rigaku scintillation tube probe?

I believe an NaI scintillator is the wrong device for optimizing a low energy ion beam. IMO, the very first step would be measuring the beam current with a faraday cup and an electrometer. Alpha’s from #1 will not make it through your window (edit: I assume you mean helium ions from an ion source no...
by Bruce Meagher
Fri Jan 11, 2019 6:19 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: How to figure out the specs of old Rigaku scintillation tube probe?
Replies: 24
Views: 1890

Re: How to figure out the specs of old Rigaku scintillation tube probe?

Harald, I’ll be following your efforts with much interest. I would imagine you’ll have to do a complete teardown to really understand what you have purchased. There is no way of knowing the signals on the connectors unless you reverse engineer the electronics inside (or get a schematic from Rigaku)....
by Bruce Meagher
Fri Jan 11, 2019 7:49 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Neutron Test Sources Po210+Be or U238+Be?
Replies: 15
Views: 1239

Re: Neutron Test Sources Po210+Be or U238+Be?

Great job trying to answer my questions. The specific activities you found are accurate, and you correctly observed the huge difference. One thing you might not fully understand yet is what the units mean. A becquerel (Bq) is the unit of radioactivity. 1 Bq = one radioactive disintegration (decay) p...
by Bruce Meagher
Wed Jan 09, 2019 3:58 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Neutron Test Sources Po210+Be or U238+Be?
Replies: 15
Views: 1239

Re: Neutron Test Sources Po210+Be or U238+Be?

Yes. Look up the specific activity of U238 and Po210. What does this tell us about the two substances? How much U238 would you need to create 1 million alphas/second? Can you find out approximately how many 4 - 5 MeV alphas/second are needed to create one neutron/second with the type of beryllium yo...
by Bruce Meagher
Mon Jan 07, 2019 8:32 pm
Forum: Vacuum Technology (& FAQs)
Topic: Cleaning/Repairing Edwards E2M5
Replies: 20
Views: 1417

Re: Cleaning/Repairing Edwards E2M5

... I still need to find a proper inlet valve for gauging. I can't find anything so far for a good price. I need it to be a KF flange which is the biggest problem. Any recommendations? You could try <https://www.ebay.com/itm/292158415411> for $12.50 shipped. The image below is what I received. It d...