Energy of fission fragments of U²³⁵, U²³⁸, Pu²³⁹

MISSING IMAGE

Material Information

Title:
Energy of fission fragments of U²³⁵, U²³⁸, Pu²³⁹
Series Title:
United States. Atomic Energy Commission. MDDC ;
Physical Description:
1 p. : ill. ; 27 cm.
Language:
English
Creator:
Snyder, T
U.S. Atomic Energy Commission
Publisher:
Atomic Energy Commission
Place of Publication:
Oak Ridge, Tenn
Publication Date:

Subjects

Subjects / Keywords:
Nuclear fission   ( lcsh )
Fission products   ( lcsh )
Uranium   ( lcsh )
Plutonium   ( lcsh )
Genre:
federal government publication   ( marcgt )
bibliography   ( marcgt )
technical report   ( marcgt )
non-fiction   ( marcgt )

Notes

Bibliography:
Includes bibliographical references.
Restriction:
Date Declassified: May 9, 1947
Statement of Responsibility:
T. Snyder.
General Note:
Manhattan District Declassified Code
General Note:
Date of Manuscript: October 25, 1945

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 005023576
oclc - 465256580
System ID:
AA00008519:00001

Full Text
7"U4P~


UNITED


30i)un'4B


STATES


ATOMIC ENERGY COMMISSION
OAK RIDGE
TENNESSEE


ENERGY OF FISSION FRAGMENTS OF U235


U238


pU239


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T, ,


T. Snyder










Published for use within the Atomic Energy Commission. Inquiries for additional copies


anid any questions


to the Technical Information Division, Atomic Energy Commission, P. O. Box E,


Oak Ridge,


Tennessee.


Inasmuch as a declassified document may differ materially from the original classified


* document by reason of deletions necessary to accomplish declassification, this
not constitute authority for declassification of classified copies of a similar do
Smay bear the same title and authors.


copy does
cument which


Date of Manuscript


October 25


Document Declassified: May 9,


, 1945

1947


- ~I~pm


. a


'i;1.This document consists of 1 page.
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MDDC
LADC


-959
- 254


regarding reproduction by recipients of this document may be referred





MDDC
LADC


- 959
- 254


ENERGY OF FISSION FRAGMENTS OF U235


U238


pU239


By T. Snyder


A foil containing 50 micrograms of U235 per square centimeter was mounted
parallel-plate pressure ionization chamber with a guard ring. A long-time-cons
fier fed fission pulses from this chamber into two discriminator circuits with a


output.


Pulses from a standard pulse generator fed onto the high voltage electro


chamber were used to calibrate the discriminator settings for ion chamber input


The response was quite linear over the region of fission pulses.


The fission pu.


curve obtained for thermal neutrons from the graphite block incident on the U23


of two peaks


The sum of the energies of the two peaks was 170 Mev, the same


perimental error as that found by Kanner and Barschall* for U238


. The striking


however, was that the minimum between the two peaks in this case went to zero
for U238 Barschall -found it only goes down to about half the peak heights.


To study Pu239


, electron collection was necessary to eliminate a pile-ups.


was rebuilt with a grid fot this purpose between the plates.


Visually the particle pulse heights looked extremely uniform.


Instead of the i


.l i : '

in a
tant ampli-
different-ial4

pulse s ie.1
se
se distribution~
5.consisteM

differene,
whereas K
<


Thec ber
iged*
Tigj di?-
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N 2^^ *^ ^ ^ W ^ 1 ^ ^ ^ *" *^ ^ ^ / K K
N' .:* .I ^!!^^' .*'
whe f%^


.= S^^ .y ... fti..i'5 .5
tangle dif-


ferential channel used for U235,
easily in one channel However,


a ten channel discriminator was employed.
this circuit was not yet entirely debugged a


limits tended to jump around thereby smearing out the pulse size resolution


amount. A trial run with U235 showed this clearly.


The interpeak minimum


Th4
ndt
by
wa;


the peak height instead of zero as before.

A U2a8 foil gave similar total energy of fragment when bombarded by fast n
through a cadmium box. This time the minimum-maximum ratio was .5 and the
closer together than those of U235.


Finally,
used again.


a one-gamma foil of Pu239 was put in the chamber and thermal


neul


he
anundfine
S one-t~hid
< *



peaos were


to~ns were


The total energy obtained was again the same within 5 Mev but the peak t 'r


much broader than in either of the other cases and the minimum-maximum ratio w
.75. In conclusion, the following sketches show the general nature of the results .
in the four measurements.


U235, Ion collection


U235


ectio


Pu239


ron collection


* M, Hf, Kanner and H. H. Barschall, Phys.


57, 372 (1940)


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