Patent US1729065A successfully refreshed from Google Patents.
Patent US3612872A successfully refreshed from Google Patents.
US3612872A
Expired / Lapsed
US
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Selective detector for fission neutrons
Assignee: United States Department of the Navy
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Filing: 1969-05-26
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Granted: 1971-10-12
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Expires: 1989-05-26
Abstract
Abstract The invention distinguishes fissionable neutron sources from nonfissionable sources by utilizing the principle that only a fissionable source emits simultaneously a plurality of neutrons during a single fission event. The simultaneously emitted neutrons are counted in a first coincidence circuit together with random pulses from neutrons emitted by Alpha ,n reactions. A second coincidence circuit counts only those neutrons which were emitted separately at spaced intervals of time by Alpha ,n reactions and does so by including a delay device in one leg of the coincidence circuit to throw out of coincidence the pulses from the simultaneously emitted neutrons.
Inventors
- 👤 Robert J Omohundro
- 👤 Frank A Marchetti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:33
CPC Classifications
G; G01; G01T; G01T3/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
173 words
A selective detector for fission neutrons comprising: neutron detector means for producing an electrical pulse in response to irradiation by a neutron; a first pulse counting circuit coupled to said detector means and including a first counter for counting every pulse produced by said detector means, wherein said first circuit includes a first AND gate having first and second inputs coupled to said detector means and an output coupled to said first counter; and a second pulse counting circuit coupled to said detector means and including a second counter and a pulse delay device coupled between said detector means and said second counter to permit the second counter to count only those pulses produced by neutrons which are emitted separately at spaced intervals of time, wherein said second circuit includes a second AND gate having a first and second inputs coupled to said detector means and an output coupled to said second counter, and wherein said delay device is coupled between said detector means and one of the inputs of said second gate.
Claim 2
Dependent Claim
173 words
A selective detector for fission neutrons comprising: neutron detector means for producing an electrical pulse in response to irradiation by a neutron; a first pulse counting circuit coupled to said detector means and including a first counter for counting every pulse produced by said detector means, wherein said first circuit includes a first AND gate having first and second inputs coupled to said detector means and an output coupled to said first counter; and a second pulse counting circuit coupled to said detector means and including a second counter and a pulse delay device coupled between said detector means and said second counter to permit the second counter to count only those pulses produced by neutrons which are emitted separately at spaced intervals of time, wherein said second circuit includes a second AND gate having a first and second inputs coupled to said detector means and an output coupled to said second counter, and wherein said delay device is coupled between said detector means and one of the inputs of said second gate.
Claim 3
Dependent Claim
34 words
The device of claim 1 further comprising: gate width generator means coupled to one of said inputs of said first AND gate and to the other of said inputs to said second AND gate.
Claim 4
Dependent Claim
33 words
The device of claim 2 further comprising: a pulse amplifier and shaper coupled to the output of said detector means for shaping and amplifying the signals to said first and second counting circuits.
Claim 5
Dependent Claim
41 words
The device of claim 1 further comprising: gate width generator means coupled to each input of both AND gateS for enabling the AND gates for a preselected interval of time following arrival of a pulse at said gate width generator means.
Claim 6
Dependent Claim
23 words
The device of claim 4 further comprising: a pulse amplifier and shaper coupled between said detector means and said gate width generator means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-11 | 1975-04-12 | 1975-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-11 | 1979-04-12 | 1979-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-11 | 1983-04-12 | 1983-10-12 | $7700.00 | Window Closed / Lapsed |