ML19332G110
| ML19332G110 | |
| Person / Time | |
|---|---|
| Site: | 07000938 |
| Issue date: | 11/30/1989 |
| From: | Masse F MASSACHUSETTS INSTITUTE OF TECHNOLOGY, CAMBRIDGE |
| To: | Soong A NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| 26131, NUDOCS 8912200176 | |
| Download: ML19332G110 (3) | |
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RETURN TO $96 SS-MASSACHUSETTS INSTITUTE oF TECHNOLOGY MEDICAL DEPARTMENT i
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$8[c$k November 30, 1989 D
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q Uranium Fuel Licensing Branch
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Division of Fuel Cycle and Material Safety J:
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NMSS NWgf Washington DC 20555 Y
,n Attention:
Dr. A.L. Soong 4
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Dear Dr. Soong:
MIT hereby requests amendment to SNM-986 to cover the planned l
purchase of 5 Reuter-stokes RS-C3-2510-114 Fission Counter / Chambers for use as neutron detectors in our proposed ALCATOR C-MOD fusion installation.
Attached is a two-page manufacgrer's descriptgn of these devices.
Each contains 1.3 gm of 2g in the 93%
U enriched uranium present.
The total amount of U present in the 5 detectors will be 6.5 gm.
The Fission Counter / Chambers will be stored and used under the direct supervision of Dr. Catherino Fiore in our Plasma Fusion Center.
They will be used to detect and quantitate neutrons in the vicinity of the ALCATOR C-MOD currently under construction.
They will be housed in secure areas and guarded against unauthorized removal. They will be included in our inventory control monitoring program.
All uses of these detectors will be subject to l
authorization and control by the MIT Radiation Protection l
Committee.
All current conditions of the SNM-986 license will be adhered to.
Please don't hesitate to contact the undersigned at (617) 245-g 6600 if further information is required.
j Yours truly, 4dde/
1 Frank Masse, CHP MIT Radiation Protection Officer
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RS-03-2510-114 F..issionCounter i
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1 For Reactor Control i.
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The RS-C3-2510-114 has proven itself as the standard high sensitivity fission counter / chamber
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for wide range reactor instrumentation 11 is designed for measurement of the neutron flux
i levels from shutdown to f ull power of a nuclear reactor.
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The detector can be used to detect individual neutrons t
(counting mode) to 106 nv in the presence of incident gamma flux of 106 Rlhr O-It can also be used as a wide-range neutron sensor in conjunction with mean square voltage (MSV) type circuitry over a range of 104 to 1010 nv in the presence of incident gamma flux of 106 R/hr Operation, as specified here, is greatly dependent g.
on associated electronics All data presented here is I
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basrd on measurements using a wide band J'.
pre amplifier.
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Concentnc cylinders with uranium coatings provicie c
k the neutron sensitive area Aluminum alloy is used in
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construction to mmimize neutron absorption and g4 s
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g'g residual activity All seals are directly bonded ceramic to metal Insulators are high purity alumina ceramic and are designed to assure stable, long-term, noise-
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free operation of the chambers even at elevated
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temperatures 4
A version of tnis chamber has a 40" sensitive fg length for core flux averaging in power reactors and is designated model RS-C3-2540-102.
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Specifications
. Q MECHANICAL
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y Maximum dianeter 8 02 cm t.
s lu'.atimum ovelall length 3318 cm L,
Connectors Ty;e HN Net weight 24k0
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h MATERIAL Outer shell and inner electrodes 1100 Aluminum L.
WMWG8W10aWil#91NhlE Conrector 6061 Aluminum Insulation Detector Alumina ceramiv i
Connector Alum $na ceramic
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Neutron sensitive matenal Uranium enriched > 93% in U 235 I
Total Quantity U 235 = 13 gm j*
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CAPACITANCE (3ue NoN. *)
Signal electrode to shell.
150 pl i
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HV electrode to shell.
250 pf
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RESISTANCE @ 25' C k
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l Signal electrode to shell 10') ohms iminimum)
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HV electrode to shell.
10'2 ohms (minimM p
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~.3 MAXIMUM RATINGS
,s Inter electrode voltage.
1000 volts i
V'4 Temperature.
300 C l i-j
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Bum up life:
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3 x 10'o yt (thermal) tot 10% decrease in sensitivity.
TYPICAL OPER ATING CH AR ACTE RISTICS
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(See Note 2)
DC thermat neutron sensitrvity.
12 x 10 0 amp /nv 120% -(
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I Counting sensitivity @ alp'la cutoff.
1 cps /nv 1.
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< 5 x 10 " amp /R/hr DC alpha current.
' 8 x 103 amp g
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.s AC alpha and noise component.
.10' nv eaulvalent
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400 to 700 volts k.
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Thermal neutron flux range c
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i in counting mode.
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In MSV mode.
10' to 10'o nv f,
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NOTE 1: With other electrode grounded i
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NOTE 2 Operating charactenstics are greatly dependent on electronics nl
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All data presented here is based on measurement using a wide ( ' ' ~ - - - - ~ - --T---
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