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THE RESPONSE OF SOME ORGANIC SCINTILLATORS TO PAST NEUTRONS*
FEB 11
V. V. Verbinski, J. C. Courtney, ** W. R. Burrus, and T. A. Love
Oak Ridge Narional laboratory
Daik Ridge, Tennessee
INTRODUCTION
INTRODUCTION ***
OR COP
A program of calibrating organic scintillators was undertaken to
make possible accurate fast-neutron spectroscopy at ORNL. Using these
calibrations, neutron spectra have been measured both with time-of-flight
techniques and by unfolding pulse-height distributions obtained from
complex spectra. Examples of the latter method were given in the preceding
paper of this session. An example of three detailed spectra obtained by
time-of-flight spectrometry is shown in Fig. 1. These represent photo-
neutron spectra from "ºo at three angles with respect to the photons. The
energy resolution in time-of-flight spectroscopy is almost limitless as
compared to the method of unfolding pulse-height spectra (assuming source
strength is no limitation) but pulsed neutron sources are of course not
always available, nor are they always best suited for studying nuclear
reactions and neutror transport problems.
For unfolding complex neutron spectra, a family of pulse-height dis-
tributions is required for monoenergetic neutrons; each normalized to one
incident neutron. The family of curves should extend beyond the range of
*Research sponsored by U. S. Atomic Energy Commission under contract
with the Union Carbide Corporation anä partially funded by U. S. Army
Muclear Defense Laboratory under order of NDL-23-63.
**Oak Ridge Graduate Fellow, Catholic University of America, Washington,
D. C.
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UNCLASSIFIED
2-C1-058-961

SE-
--
55 deo
93 deg!
RELATIVE FLUX ( neutrons.steradion". Mevº,
e
tc.-
141 deg
°
2
4
6 8 10 12
NEUTRON ENERGY (meV)
14
16
Fig. 1. Photoneutron spectra from the 9017,n)'yo reaction produced
by 34 MeV end-point bremsstrahlung. Time of flight spectrometry was used,
with a gamma pulse width of li ns and a flight path of 55 meters.
energies that is to be covered by the meusurements.
One such curve for a neutron of energy E, when integrated from maxi-
mum pulse height, Lmay down to a pulse height be the bius setting, yields
the efficiency of the detector for neutron energy E. An efficiency curve
developed from such monoenergetic neutron response functions is used di-
rectly in time-of-flight work. This efficiency factor places ne of the
greatest limitations on the accuracy of time-of-flight measurements.
The encapsulated NE-2134 scintillator (factory deoxygenated) was
chosen because it can be used very well with pulse shape discrimination
circuitry to eliminate gamma counts. When gamınas are no problem, as in
some time-of-flight applications, the NE-21l scintillator can be used if
the slow component of light einission from NE-213 should prove undesirable
(as in some LINAC time-of-flight applications).
The total (fast plus sluw)
light output of the two materials is nearly identical, as referenced to
the light produced by "co, so that the response functions presented here
are suitable also for NE-211.
Stilbene is a superior scintillator in resolution
rly a factor of
two better at 14 MeV but only slightly better ut 3 MeV for scintillators
about 1" in size), in pulse-shape discrimination properties (larger fruc-
tion of slow-component of photoemission), and in light output (~20%
higher). But stilbene has a slightly lower hydrogen density than NE-213,
is easily damaged by mechanical or thermal shock, cannot be obtained in
large sizes as a monocrystal, has too long a slow component for many LINAC
type time-of-flight measurements, and it gives a recoil-proton light output,
In, that varies with crystal orientation by perhaps 15% (this was observed
several years ago and confirmed by one of us, vvv), while it does not do
ho
S for it gaina source used for calibrating the light scale. Îne would have
to determine the crystal axes for the stilbene used in the calibrations,
have all successive crystals cut accordingly, and subsequently irradiate
along one particular axis before accepting, calibrating and utilizing stil-
bene for precision measure.nents.
Two sizes of NE-213 scintillutors were cullbrated; 2" x 2" diam and
5" x 5" dium. In time-of-flight work, these can be used directly or as
stundurds to calibrate large tanks of scintillators. In pulse-height
striping, one cannot in pructice use one scintillator type or size to
cross calibrate a different size or type; only cross comparison of final
spectral shape and intensity is practical.
II.
THE INITIAL MONTE CARLO CALCULATIONS
The response of the scintillator to monoenergetic neutrons of energy
E was obtained by a Monte Carlo calculation in which a plane parallel beam
n
of neutrons "irradiates" the scintillator uniformly. The 05R system of
Coveyou et al.,' of ORNL was applied to this problem. Individual neutron
histories are developed, and each neutron is followed until it escapes, is
absorbed, or is reduced in energy below .020 MeV.
The 05R program was run
for each neutron energy E until 25,000 collisions were recorded (N =
25,000). This yielded a calculated pulse-height distribution containing
25,000 "counts" as produced by a total of N. incident neutrons. The re-
sulting pulse-height distribution was divided by the total number of in-
cident neutrons, Nm, which converts the pulse-height distribution to
absolute efficiency. The "zero-bias efficiency" is then equal to N/N.
The zero bias efficiency for each value of E agrees with an exact analytic
.
.
t
i
_:
-50
calculation [l-exp(-£2. T)] within the Monte Car. statistics.
The cross sections for scattering of neutrons by the hydrogen was
taken from BNL-325 and for the carbon of the scintillutor the NDA library
of cross sections was used. This source provided both the elastic and
inelastic [ 12c(n,n')2c] differential cross sections for carbon. These
appear to be adequate up to an energy of about 10 MeV, above which (n,a),
(n,p) and (r1, pn) cross sections (in order of increasing energy of "impor-
tance") become important.
These reaction cross sections and their con-
tribution to the response functions are discussed in detail later in this
communication. Hydrogen scattering and carbon inelastic scattering are
assumed to be isotropic in the center of mass system. The differential
elastic scattering cross-section from carbon was accurate to a P-8 angular
approximation.
A rumber of experimental measurements were made in order to provide
additional inputs required for the Monte Cario calculations and to check
the accuracy of these calculations.
III.
PULSE-HEIGHT DISTRIBUTIONS BELOW 10 MeV
First, pulse-height distributions were obtained for a series of mono-
energetic neutrons varying in energy from 0.2 MeV to 14.7 MeV.
These were
mostly reliable only at the upper end of the pulse-height spectrum. The
ORNL 5.5 MeV Van de Graaff was used with the 'H(p,n) He reaction to obtain
monoenergetic neutrons from 0.2 MeV to 4 MeV.
The Ch(a,n) He reaction was
used to obtain monoenergetic neutrons to about 8 MeV, and the 'H(d, n) He
reaction to produce 12-15 MeV neutrons.
A 300 keV electrostatic accel-
erator was also used for additional measurements at 3.1 MeV and 14.7 MeV.
-6-
In all these measurements, T-Zr and D-Zr targets were used. Dummy (blank)
Zr targets were also used to determine the background due to gammas and
neutrons from contaminating reactions, such as c(a,n)?C (Q = +.29 MeV)
due to carbon (from pump oil) contamination of the Zr target. Above
1.5 MeV, pulse-shape discrimination was used to reject gamma counts. În
this first series of measurements, the detector was placed near the Zr
target, the pulse-height distribution was measured, and the dumury target
was then put in place and the background determined for the same integrated
beam current. A sample of such measurements is shown in Fig. 2, along with
the pulse-height distribution from £. 6°co source which is used as a stan-
shown as the extrapolated end point of the Compton edge from the 1.17 MeV
and 1.33 MeV gammas of
co. For our arrangement of scintillators, (en-
capsulated, deoxygenated NE-213 scintillators, vertical mounting, painted
with a white reflector by Nuclear Enterprises Corporation of Canada and
optically coupled to the photomultiplier tube with Dow Corning 100 cs
grease.), photomultiplier, and amplifier, one "cobalt" is equal to the light
produced by a 1.27 + 0.02 MeV electron, as determined by the relationship
:
between pulse-height distribution and Compton-edge energy given by Flynn
et al.?
These pulse-height distributions were used to cbtain a trial function
for L (E), the light iroduced by a recoil proton. For the trial function,
plotted against the maximum proton-recoil energy, E. (max) = En, for about
fifteen values of E, from 0.3 to ~15 MeV. This curve was then fitted by
8
adjusting the parameters A and B of Birk's formula
UNCLASSIFIED
ORNL DWG 64-10761
2400

2000
oyoo.. INCIDENT E, -- 4.95 MeV
INCIDENT En = 4.91 MeV
COUNTS PER CHANNEL
%-
6°CO CALIBRATION
SPECTRUM
wool como globoacide
Poproszony
0
40
80
120
160 200 240
CHANNEL NUMBER
280
320
360
400
Fig. 2. Typical experimental pulse height distributions from a 2" x 2" diam
NE-213 scintillator exposed to 1.91 MeV and 4.9 MeV neutrons and co gammas.
App A dE
p" Jo It B(AE/dx)
with values
9-12
derived from the literature
for the scintillator
with values dE/dx derived from the literature 9-12 for the
NE-213 !CH,). Fitting with Birk's formula was valuanle in extrapolating
the L (E) function between measured points, and to both higher and lower
energies. This function was then used in the initial set of Monte Carlo
calculations.
These initial calculations produced pulse-height distribu-
tions that had a sharp dropoff at the right, so that these distributions
had to be smeared to match the smearing due to photomultiplier statistics,
nonuniformity of light collection, nonuniformity of the photocathode, and
amplifier noise. Individual log-log plots of both the measured and cal-
culated pulse-height distributions were made on tracirig paper to help check
the proper smearing of the calculated response. Once the proper shape was
obtained for the right-hand part of the curve (these early experimental
data were, in general, reliable only at the right-hand half of the curve),
the overlaid plots generally resulted in a mismatch of the abscissa for
the measured and calculated plots. This mismatch provided a correction to
the initial experimental light curve, a correction that arose from assuming
the light produced by E (max) = E could be correctly obtained from the
half-height of the recoil proton pulse-height distribution. This error
is large for small values of neutron energy E. (Ref. 13).
In Fig. 3 is shown an 'I (E) curve for NE-213 obtained with the pro-
cedure outlined above. All curves in Fig. 3 are also correct for NE-211.
As a result of this initial effort, we obtained pulse-height distri-
butions that were reliable below 10 Mev, ignoring the smaller pulses
UNCLASSIFIED
ORNL-DWG 64-10753R

PROTONS
.
LIGHT OUTPUT (COBALT UNITS)
ALPHA PARTICLES
12C NUCLEI
0.01
0.4
10
ENERGY OF PARTICLE (MeV)
Fig. 3. Light response of NE-213 lo proluns, alphus, and carton
recoils. The light unit was taken as the 60Cu extrapolated end point
of Fig. 2.
-10-
produced by carbon recoils.
Therefore, the next task was to obtain the
light r'unction for carbon recoils, L., so that the low pulse-height end of
the spectrum could be accurately computed.
For neutron energies above 10 MeV, production of alphas from --
becomes important.
Therefore the L. (E) function also had to be determined.
IV. RECOIL CARBON AND ALPHA LIGHT FUNCTIONS
The L. (E) and L. (E) functions cunnot be obtained by use of Birk's
formula with the constants A and B derived from the above curve-fitting
for Ln, because of the large uncertainty in the electron excitation cross
section (2E/dx) for a's and recoil carbon nuclei. Only the total dE/dx
is accurately known. It also contains a part due to collisions with
nuclei, (aE/ax)mune which does not contribute to the light producing
process. 14
The carbon light function was derived from three sources. First some
preliminary information was available on work by Steuer und Wenzel" who
reported that for carbon recoils from about 1-5 MeV, the light produced in
NE-213 was 0.006 + 0.002 of that produced by electrons of the same energy,
and for the NE-102 plastic scintillator, the corresponding figure was
0.016 + 0.002. This, incidentally, suggests that NE-213 is the more de-
sirable for many applications, because one can bias down to say 1/3 the
pulse height without interference from carbon recoils which are difficult
to calculate accurately.
We obtained a pulse-height distribution for carbon recoils by 110"
scattering of 14.4 MeV neutrons off carbon.
The experimental arrangement,
shown in Fig. 4, utilizes a deuteron beam from a 0 keV to 300 keV positive
UNCLASSIFIED
ORNL - OWG 64-10719

AMP
DYNODE 10
PRE
AMP
ANTICOINCIDENCE
CIRCUIT
OYNODE 14
2-in. DIAM * 2-in. HIGH
NE-213-
L.L. DISC
IN VACUO
U.L. DISC
U.L. DISC]
DEUTERON
BEAM
T TARGET
~90cm
HE VIMET
SHADOW
SHIELD
FAST
AMPLIFIER
COLLIMATOR
ABSORBER FOIL
5-in. DIAM
2/2-in HIGH
NE -213 ON
58 AVP
INPUT
-TT-
DYNODE 14
OYNODE 14
ON
TRIGGER
RIDI
400-CHANNEL
ANALYZER
LL DISC
U.L. DISC
L.L. DISC
ANODE
U....DISC
ANTICONCIDENCE
ANTICOINCIDENCE
CIRCUIT
ANTICOINCIDENCE
CIRCUIT
COINCIDENCE
CIRCUIT
Fig. 4. Block diagram of apparatus for measurement of pulse-height
spectrum of recoil carbon nuclei.
-1.2-
ion accelerator, a thin tritium target and an alpha detector (with colli-
mator and absorner foil) chat detects the alpha particle associated with
the 14.4 MeV neutron in the 'H(d, n) *He reaction. A 2" x 2" NE-213
detector is placed in the cone of neutrons associated with the detected
alphas, and a large (2" x 5" dian) NE-21% scintillator is placed so üs to
detect neutrons scattered at 110° from the thin neutron detector. The ulphu
counter is biased (:1pper and lower bias) to accept only alphas from the
He(a,n)*He reaction, the thin neutron counter is biased to a very low
level, and the thick neutron counter is biased ut ubout y MeV so as to
count mostly neutrons singly scattered off curbor. at 110°. A triple
coincidence between alpha, thin neutron-detector und lurge neutron-detector
allows a pulse from the thin detector to be stored in an analyzer running
in the coincidence mode,
The resulting pulse-height distribution is shown
in Fig. 5.
The spread in pulse height is, of course, large due to the poor
photomultiplier statistics at a light output of 0.018 "cobalts". This is
equal to 0.008 + 0.002 of the light produced by an electron with energy
equal to the 2.85 MeV carbon recoil (assuming I "cobalt" = 1.27 MeV-
electron light output), which is in agreement with the work of Steuer und
Wenzel.15
The third check on L. (E), the carbon-recoil light function, was ob-
tained by matching the measured pulse-height distribution, in the pre-
cision experiments described below, with a Monte Carlo calculation in
which the L. (E) curve and the smearing width were adjustable constants.
The response of the NE-213 scintillator to ulpha particles was ob-
tained at energies of 6.1 MeV and 4.76 MeV by measuring the pulse height
from <*cm and <34U alphas plated on a platinuin foil placed inside in
UNCLASSIFIED
ORNL DWG 64-10762

0.018 COBALTS
COUNTS PER CHANNEL
-13-
1
10
20
50
60
70
30 40
CHANNEL NUMBER
Fig. 5. Carbon-12 recoil pulse height spectrum from 14.43 Me V
neutrons scattered at 110°.
-3.4 -
NE-213 scintillator and calibrating the light scale of these scintillators
with gammas or known energies. This yielded the two corresponding points
(with error bars) on the L, curve of Fig. 3. The square points shown on
the same curve of F. 3 were inferred from the precision 14.43 MeV pulse-
height distribution obtained with the ?ssociated particle technique as
described below.
V. PRECISION EXPERIMENTS
It was possible for us to obtain accurate pulse-height distributions
for two neutron energies, 2.66 MeV and 14.43 MeV by means of the associated
particle technique. The experimental arrangement is shown in Fig. 6. A
2" x 2" NE-213 scintillator and 56 AVP photomultiplier tube were used at
14.43 MeV, and I" x 5" diam NE-213 and 58 AVP at 2.66 MeV. The 14.43 MeV
distribution was obtained by demanding coincidences between the 14.43 MeV
neutron and the associated alpha particle in the 'h(a, n)*He reaction, and
the 2.66 MeV distribution by demanding coincidences between the 2.66 MeV
neutron and the associated 'He particle from the ?h(a, n ) He reaction. A
coincidence gates on the analyzer, which then scores a pulse from the
neutron detector.
In this way, photomultiplier noise pulses and back-
grcund counts are almost completely eliminated.
In Fig. 7 are shown two pulse-height distributions, one for 2.66 MeV
neutrons and one for 14.43 MeV neutrons. The one at 2.66 MeV fits the
calculated curve quite well.
The pulse height distribution for the 14.43 MeV neutrons covered a
range of light output from 14.43 MeV recoil protons down to <0.01 "cobalt".
The lowest bump in the 14.43 MeV pulse-height distribution (.01-.04 cobalts
UNCLASSIFIED
ORNL - DWG 64- 10720R

TO INPUT
DYNODE 10
PRE - AMP
AMP
-
-
-
OYNODE 14
ANTICOINCIDENCE
ANTICOINCIDENCE
DYNODE 14
L.L.
DISC
58 AVP
COINCI-
DENCE
CIRCUIT
ANODE
U.L.
-15-
DISC
NE-
213
INPUT
NEUTRON CONE –
?H OR 3H TARGET
RIDL
DEUTERON
BEAM
TRIGGER
COLLIMATOR
TARGET - DETECTOR
HOLDER (IN VACUO)
400- CHANNEL
ANALYZER
ABSORBER
FOIL -
3HE OR “HE
DETECTOR
U.L.
DISC
FAST AMP
L.L.
DISC
-ANTICOINCIDENCE
Fig. 6. Block diagram for measurements of absolute efficiency and
low-bias pulse-height distributions.
UNCLASSIFIED
ORNL-DWG 64-10755R
A
6°CO CALIBRATION
SPECTRUM
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bococco
-
-
"
Somo
V
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.
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r
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-
.
.
poco conos.com
PROBABILITY OF EVENT PER LIGHT UNIT
"!
.
HO
T-
-
= 14.45-MeV NEUTRONS INCI-
E DENT ON CURVED SURFACE O
2-in-diam x 2-in. NE-213--
.....
- -
-
-
-
-
-
-
-
-
-
.-
-
-
0.01
..
.
:
.:
:
:
2.66-MeV NEUTRONS INCIDENT
E ON CENTER OF FLAT SURFACE
OF 5-in.-diam x 1-in. NE-213-
......
----..... .....
.
.
0.001
0.01
0.1
PULSE HEIGHT (LIGHT UNITS)
Fig. 7.
Comparison of measured and calculated pulse height distributions.
in Fig. 7) arises from carbon recuils alich is l'epruced iirly *:11 by the
Munte Carlo Calculati.". Cae rexi tai bus 'il'e cientifici C(:.,:.'; e)
14
reactions proceeding by way uf
12 cin, nit?
22 ct
8 Be
The lower of these twj burnps is nos ciaüed with alpha missi:!! via excit:i-
tion of towu the 12.73 MeV level by neutrud elastic sca:tering, and the
higher of the two buips is assziated with excitatiit. if
to the 9.63 !!@V
level. The Monte Carlo calculation fits these bumps rather well, except
trat it indicutes that an additional 5% alpha decay via +2C+(~11.1 tev) is
of 257 mb with a 40%, branching 12cm 19.63 kev) und 60% for 12C+(12.75 MeV).
The two prwiinient bumps helped extrupulate the L, (E) curve i luw energies,
in that small adjustments of L, (E) nud to be made to properly locate ine
170 (n, n'ou) bumps.
The shoulder at about 0.9 "cobalts" which is due to the cín, c) BE
(ground state reaction) was reproduced in the Monte Carlo calculation by
using the angular distribution measured by Chatterjee and Ser
for id:14:
particles emitted by 24.5 MeV neutrons. The calculation reproduced this
measured detail rather well, and this verifies the extrapolation f the
L (E) curve of Fig. 3 from the 6.). MeV point (directly measured with the
24-Cm alphas ) to about 9 MeV alpha energy.
-18.
VI. OUTPUT
The plotted values , Lo, , and L. f Fig. 3 are also given in
Table I t: eliminate the error associated with making, and reading the plot.
dis result of the experimental inerisurements of L (E), L (E), und L. (E),
f
btaining the pr per smearing as a functiun ut light output (or pulse
height), und f btaining the prper (n,u) kinematics for ?.eutrons un
tec, we obtained response functions for values of E up to 11.43 MeV.
These üre shown in Figs. 8 und
for the glass-encapsulated 2" x 2" dian
NE-213 scintillator, vertical mounting und with the white reflector paint
:: 5 t?plied by the ranuructurer, ünü atticheù tu un RCA 6810-A phot:multi-
vlier with Dow Corning 10° centistokes silicone compound.
In Figs. 10 and
ll
re shuwn the response functions of u 5" x 5" diaineter gliss-encapsu-
lated liquid scintillutor. The encapsulation was for horizontal mounting,
and was painted ith white reflector paint by the manufacturer. The tube
was coupled in a Phillips XP-10149 flat-faced photomultiplier tube with
General Electric LTV 602 potting compound.
The initial Gaussian smearing widths applied to the Monte Carlo re-
sults were plutted ind fitte with the following functions. Fir the 5"
scintillátor, AL./L = 0.253 10.for 1 2 0.15 "cobalts", and 0 L/L =
2.374 L-0.25 for 1 <0.15. For the 2" scintillator, AL/L = 0.180 1-0.5
für L = 0.12 und AL/L = 0.35 L-Oots für < 0.12. Here AL is the full
width at half maximum of the Gaussian sinearing function.
As was indicated several times above, the efficiency of either the
2" or 5" detectors for an arbitrary bius setting Lg und for an energy En
can be obtained by simply integrating the curves of Figs. 8 and 9 (for the
2" detector) »r Figs. 10 and 11 (5" detector) from Lay down to Lg. Such
Table 1. Light Output in "Cobalts" us in Functio. f Particle
Energy for Protons, Alphas, and Carbon-12 Recoils.
Energy (MeV)
Pritons
Alphus
Cirbon
20.Co
17.80
15.80
ll.10
12.60
11.20
10.0
6.4000
5.0000
3.96000
3.0500
2.3000
1.8000
1,3800
1.0300
.8000
.5900
1500
.1900
.1620
.1380
.1170
.1010
.0900
.0780
.0670
.0570
.0500
10.55380
4.06570
7.74480
6.65230
5.71570
4.86900
4.16520
3.54600
3.08000
2.65000
2.25000
1.92000
1.61000
1.40000
1.18000
.98000
.82000
.70000
:5000
.48500
.40000
.33400
.01130
.34650
.2780
.2220
.1850
5.62
5.01
4.47
3.98
3.55
3.16
2.82
2.51
.0390
.0312
.0310
.02744
.02443
.0223
.019
.11175
.1200
.1000
.0820
.001:0
.0180
2.24
1.78
.0162
.0148
.0134
.0120
.0108
.0100
.0480
.0103
.0340
.0290
.0248
1.58
1.41
1.26
1.12
1.00
0.891
0.794
0.708
0.631
0.562
0.501
.0181
.0156
.01344
.0115
.0101
.23080
.19000
.15900
.19000
.10820
.09070
.07650
.06460
.051470
.014660
.03970
.03390
.02920
.02520
.02190
.01910
.01680
.01475
.01301
.01148
.01022
0.355
0.316
0.282
0.251
0.224
0.200
0.178
0.158
0.141
UNCLASSIFIED
ORNL-DWG 64-10756R

- 60CO CALIBRATION
SPECTRUM
0.2 MeV -
w
: 0.6 MeV
1.56 MeV
PROBABILITY OF EVENT PER LIGHT UNIT
.
-20-
| 3.96 MeV -
- 14.43 Mev
0.01
0.01
0.1
PULSE HEIGHT (LIGHT UNITS)
Fig. 8. Absolute differential efficiency for a 2" x 2" diam NE-213
scintillator for neutron energies shown.
UNCLASSIFIED
ORNL-OWG 64-10757R
100

0.335 MeV
60CO CALIBRATION SPECTRUM
0.946 MeV
1.94 MeV
PROBABILITY OF EVENT PER LIGHT UNIT
-21-
58.12 MeV
|
0.01
0.04
0.02
0.05
0.1
1
0.2 . 5 0.
PULSE HEIGHT (LIGHT UNITS)
Fig. 9. Absolute differential efficiency for a 2" x 2" diam NE-213
scintillator for neutron energies shown.
UNCLASSIFIED
ORNL-DWG 64-10759R

-0.2 Mp!! -
0.6 MeV -
60 CO CALIBRATION SPECTRUM
1
A 4.0 MeV
2.0 MeV
PROBABILITY OF EVENT PER LIGHT UNIT
-22-
4.0 MeV
7.0 MeV :
-
-
-
-
-
.
MW
0.01
0.04
0.02
0.05
0.1
0.2
0.5
PULSE HEIGHT (LIGHT UNITS)
Fig. 10. Absolute differential efficiency for a 5" x 5" diam NE-213
scintillator for neutron energies showri.
UNCLASSIFIED
ORNL. DWG 64- 10758R
100

0.4 Mev.
60CO CALIBRATION SPECTRUM -
-
0.8 MeV.
.
-
1.5 MeV
-
M
.
-
-
-
-
-
-
3.0 MeV
i
-
-
PROBABILITY OF EVENT PER LIGHT UNIT
***
-
.
.
.
einidhi
* II
1.
"
11 O MeV ---.
.
4
we
.
erence
-
-
-
-
-
II
0.01
0.04
0.02
0.05
0.1
0.2
0.5
PULSE HEIGHT (LIGHT UNITS)
Fig. ll. Absolute differential efficiency for a 5" x 5" diam NE-213
scintillator for neutron energies shoitia
-21-
integration has been done, and the running sum is given for many values
of E in Tables II (2" detector) and III (5" detector). Fron this can be
constructed efficiency curves such as those shown in Fig. 12 for both the
2" and 5" detectors (2 bias levels for each).
These curves are used di-
rectly in our time-of-flight data handling code, and they yield total abs ,-
lute tiine integrated flux incident on the detector during a time-of-flight
spectral measurement.
For use in unfolding pulse-height distributions, the response func-
tions (the differential efficiencies) ure given for 12 energies for the
2" detector ir. Table IV, and for 15 energies fi:r the 5" detector in Tuble V.
VII. SCINTILLATOR RESOLUTION
For unfolding pulse-height spectra to obtain energy spectra, it is
important to select a scintillator with reasonably good resolution. The
resolution has been measured for a number of scintillators and was found
to be a sensitive function of scintillator size, the optics of the scin-
tillator photomultiplier combination, and scintillator material.
For 144 MeV neutrons, the 5" x 5" diam NE-213 scintillatiir with white-
paint reflector gave a resolution of about 15%. The 2" x 2" diam scintil-
lator with white-paint reflector yielded 11%. Replacing the paint with a
loose aluni num-foil reflector reduced this figure to 6.5%. This is further
reduced to about 5.5% for a 15 x 15 dian or a l" x 1" diam NE-213 scin-
tillator covered with a 2" x 2" diam tent of aluminum foil. A 1" x 1" diam
stilbene crystal, packed in Mgo reflecting powder yielded about 3.6% and it
l-cm x 2-cm diam stilbene with close fitting aluminum reflector yielded
about 3.2%. The resolution was obtained from the straight line portion of
-25,-
Tuble II. Detector Erficiency as a function of Blus (in "Cubalt" Units)
for Plane Purullel Mulutnerrullo Neut l'ulls Petipendicular tv Axes
ut 2" x 2" dian Cylinder ut' NE-21., Scintillutur.
NEUTRON EFFICIFICY vs HIASMR 2 IN HIlim. 2 IN DIAM. NE-215
* NEUTH ON ENERGY IN MEVE
.335 .00 .946 1.25 1.50 1.91 2.98 3.96 5.47 8.12llon 14,4
DIAS
.in
.612
P13
11:15
012
.1! 21
.
.575 554
.546 541
.512 526
74697509
. 416
.350
.272 441
. 169
113 371
323
.n24 262
143
124
.001 ono
on31
0012
003
001
0
,023
. C26
.l30
..35
.(40
.646
.C.32
(60
,057
.008
.N02
.505 454 442 .403
497 45.3437 399
489 447 432 .394
. 479 .4411 .426 ,391
.468 43.3 .420 387
.456 .425 .414 382
442 415 .4U0 .377
.427 405 .349371
410 .394 3911 .304
.342 .381 .38 1 ..357
.367 .310 350
345 351 .359 341
316 334 346 332
280 314 352 ,322
236 291
1647263.290 29A
,128 231 279 284
078 192 .256 269
039 14M 229 251
.016 102.196 231
.005 060 158 208
.001028 116 1181
0 000 014 149
002 036 112
011 074
0 .002 034
012
,00?
ņ
.669
.679
ma
;91
. 105
. 120
. 138
.159
414,5
• 182
.609
.240
275
316
.363
.350 ,312 .205 226 .214 191
.343,305 .257 .214 .20A 18H
.339 .294 ?49 .? .?Q1.
335 29.3 .24.3 .204,195 .181
.331 .289 239 200 189 177
328 .200 .235 196
.183173
183
.325 283 23.3 194 179 170
321 .281 231 192 176 167
,31? .27A .?29 419 .124 2165
.313.270 227 19 172 164
309 .273 225 ,189 171 163
304 .270 .223 IBA 170 162
.299 267 221 18A 169 16
293 26.3 .219 185 16A lon
.287 .259 .210 18.3 : 165 159
.281 255 214 182 el 157
.250 21 180 159 154
266 .245 20R 17A 155 152
258 .240 205 177 152 149
.249 .234 20 173 148 149
.239 .228 . !9A 121 .145
228 221 .19416A 142 142
215 213190 165 139 JA
2011 204 166 162 136 134
185 . 195 181 15A 132 12A
107 185 186 154 129 123
.147 173 171 149 127 LA
122 159 165 145 1125 114
196 .14.3 158 139 122 olin
NOA ,125 151 134
100
104 142 12A a116 10?
079 133 122 112 097
053 121 Il 15 !A 2093
on27 109 TUA 104 189
005 395 101 099 066
0 079 on93 094 083
O non 083 087 080
0 037 072 081 076
015 .059 073-ler?
0 001 044 066 067
0 02 057 062
Din 047 056
.036 050
n23 043
10.9.2034
.025
.479
. 549
.631
.224
.832
.655
1.096
1.259
1,445
1.660
1.905
2.108
2.512
2.884
3.311
3.202
4.365
5.712
5.754
6.607
7.586
8.710)
OOOO
cccccccccccococcoccicccoo
csocoooooooooooooooooo
осоlc cocccic ccocccccc
Oo
соо eccocccic cocc
oooooooco
IC
ссс! ccccc
003
o Jo
ccc
EFFICIENCY AS A FUNCTION OF BIAS FOR A SIN DIAM BY 5 IN HIGH NE-213
BTS
п, 20
о.40
0.00
0.00
1.00
1,25
NEUTRON ENERGY IN MEV
1,50 2.00 ,00 4,00
5,00
1,00
9.00
1,0
14,4
СТО
«С12
С 13
.T5
• 2
(27
(23
. 26
.C30
• 035
ост
.619 ,866 873 860 .855 03:
540 ,846 ,863 848 846,825
.45, в 19 ,852 835 837 , 19
366 779 839 ,821 826 R13
282 722 822 806
„205 646 ,ВОО ,789 ,803 ,297
140 552 ,770 770 ,789 788
п39 445 730 ,748 774 277
.053 336 ,673 722 757 765
029 235 593 089
оп14 15 503 645 ,2 12 736
„По? ОВА 395 „566 681 ,2 17
047 ,285 ,508 ,640
о „п 22 186 4) 505 665
o oo o ,ТО9 30 32 628
004 OST 21п
„ПОТ 025 126 322 512
одно.О66 22 1 4 29
ООЗ030 ,134 334
ООт о т о70 237
o ОО: 030 .147
.00 .009 (76
п ОО2 ,п31
ороо
C52
)
,419
ос69
1
• 105
. 12,
134
. 159
вул. „279 23 685 ,622
806 775 764 678 t 12
801,271755 ,671 ,11
795 ,67 745 665 ,610
762 735 659 .602
78 757 725 653 603
273 751 715 647 600
,765 744 705 ,641 597
255 ,737 495 63. 59
,744 ,128 685 630 591
73 ,219 625 62, 587
,2 17 709 665 ,61A 583
20 697 654 612 579
,682 684 64, 60, 57,
659 670 631 ,599 569
65, 6 в 592 563
59 634 605 583 557
546,612 591 57. 55,
483 585 575 565 541
404 55 559 554 ,535
31. 502 540
527
.219 451 520 52, 512
. 131
495 5 4 502
.o6. 296 466 492 49
207 , 433 479 483
по 5 .124 392 457
0 ,059 340 432 ,
.019 277 ,402
„Поз ,2C5 365 ,413
г . 1 32 32 г 388
п ,007 ,264 357
поп21 ,19A 521
пO3 13 27
, 267 217
,П2 п .151
ПО? Св.
п .п3
пO4
на I
„209
24)
275
316
163
564 539 52А, 492
,556 527 517 , 483
549,515 505 474
341 .50
,493 466
53а 49, 481,450
533 ,486 ,469 ,45)
529 480 459
526 474 450 438
52 5 470 412 4 ?
52 1 407 436 423
51а 464 431 424
5 15 46 427 422
512 459 422
50А 456 414 416
50. 453 414 41
501 450 409 409
495
405
49, 443 399 4 yo
405 439 394 395
479 434
,39c
17. 429 381 , а
464 424 377 378
,455 ,418 372 37 р
446 4 1 367 359
,436 4 0 4 36 347
395 355 334
415 386 34a , 321
404 374 ,34)
309
392 361 332 29А
38 347 123 ,237
36, 332 313 216
, 35, 36, 3 ( 2 ,205
331 300 291 253
Зоо 284 279 243
,283 267 265 235
251 252 25г 227
2 IT 232 234 219
,161 211 21A ,2 10
, С .185 гог , 199
, 154 , 152, 18 17
отп . .159 124
„Пое 132 158
,П26 09A ,142
ООГ .059
124
с . 123 101
„ПОТ 072
-2С-
5" x 5" diam Cylinder uľ NE-213 Scintillator.
for Plane Parallel Mülluchergetic Neutrons Parallel tu Axes of
Tuble III. Detector Efficiency as a Function or Bias (in "Cobalt" Units)
•435
•
479
49
3.
•
•
•
•
с. сссссссссссссссссссссс. с сос с
•
224
„E32
555
1,096
250
1,445
1.6п
1.02
a,
2..12
2,984
3.30
3,EO2
4,165
1.c12
5.754
6,07
7,86
•
cc cccocc ccccoic coococoocc
oc cccc. cocccccccccc
mic cccccc Coocole oocc.
с сссссссссссс
MN - CCC
clc cccccccccc
cccccccccc
се сосе
„Оy9
cccc
UNCLASSIFIED
ORNL-DWG 64-10754

- CYLINDRICAL NE 213 SCINTILLATORS
-
-
-
5-in.-diam x 5-in.; BIAS=0.04 COBALTS
-
-
--
-
-
-
-
-
-
--
-
-
EFFICIENCY
-2;-
-
.
5-in.-diam x 5-in.;
BIAS=0.08 COBALTS
.............
.....
......
--
0.2
W
- 2-in.-diam x 2-in.;
BIAS=0.04 COBALTS
42-in-diam x 2-in.; -
ill BIAS=0.08 COBALTS :
----------------------.............
....
co
1
2
3
4
11 12
13
14
15
5 6 7 8 9 10
NEUTRON ENERGY (MeV)
Fig. 12. Typical neutron-detection efficiency functions as used for
analysis of time-of-flight data.
PUI SE HEIGHT
0.335 MEV
0.6 MEv0.945 पEv
25 NEVISO MEV
1,91 MEV
371
19.089036
10.371890
.716326
20.145219
20.663601
21.258274
21.902369
22.567061
23.224800
23.859646
24.463748
2531565
25.550417
25.90642
26.300581
26.410219
26.239548
75.71706
24.785360
23.43619
21.693169
19.625241
17.331893
.319968
.249904
5,1769..
७.109389
,,052390
5,00701
4,97004
4,9390.8
4,906604
48700.0
4.2786.
T720
4,730870
4.630609
4,631749
4,34743
4.39353
कारबाण
4.450709
4,40712
4,364405
4.323515
4.235357
.0105
.010
.015
.0120
.0126
.017
.013.
.0145
.0151
.015
.0166
017
.0102
.0101
.0200
.0200
.0210
.
.0240
.0251
.0263
.0275
.0288
र
.0316
.0331
.0347
.0363
.03a0
.0390
.0417
.0437
.0457
.0419
.0501
.02
.0550
.0575
.0603
.0631
.0661
.००
.0724
.0759
.0794
.0832
.0871
पर
.0955
परक
8.884234
3,825534
8.767020
8,722230
..698753
1607AN
8.710398
8.730377
.,741823
8.757074
8.751195
..ाहा
8.747964
..753667
..776755
8.824010
..901140
.013055
9,163935
9.356706
9.592261
9.868701
10.180451
TOगर67
10.860835
11.214167
।।.530656
1788567
11.952865
।।.901937
11-852747
11,527284
10,998336
TO.273585
9.3801।।
ठा
7.270679
6.164701
5.005549
4,105717
3.225002
वहा67
1.844221
1.342898
.953606
660380
.445991
720
188627
उ.967
3.869446
3,772750
3.602205
3.602102
3.534875
3.400430
3.436410
3.3.9116
3.364775
3.330501
3,295247
3.2.37
3.222745
3,137873
3.155005
3.124129
3.094618
3.065575
3,036274
3.006325
2.975672
2.944456
2.012755
का
2.847843
2.814524
2.790738
2.746000
2.713220
2.600668
2.619891
2.621718
2.59.6976
2.576475
2.560979
म्हारब
2.685975
2.535228
2.408003
2.303191
2.219034
2.152693
2.100448
2.0582।।
2.022195
1.989496
1.958371
T155
1.898913
1.870019
1.844238
1.010595
1.793399
1767975
1.741803
।.714680
1.686720
।.658349
1.630013
Tooरा
1.575274
।.549555
1.525103
1.502145
1.48031।
1.459406
1.439084
।.419025
1.398988
1.378863
1.358698
TIJ०००
।.318970
।.299837
1.201395
1.263677
1246634
T20
।.214213
1.198762
1.103914
1.169893
1.156978
4,220647
4,15725
4,17700
4.155614
1,162010
4.17064
4,199556
4,222163
4,269736
4.333522
4.414017
उपर563
3.311890
3.204320
3.105990
3.010674
2.946667
2,086210
१.835757
2.791682
2,750312
2.708013
2.665692
2.620763
2.574850
2.32894
2.483877
2.439928
2.396956
2.3458
2.312571
2.270968
2.23015
2.190897
2.153873
सामा16
2.089195
2.062310
2.039032
2.010054
2.000917
।.984056
।.967016
1.948700
1.928399
1.905742
1.881135
TOSमरण
।.829161
i.803782
।.179984
1.758328
।.739110
मरा
।.708264
1.696758
1.688130
1.682086
।.661222
TOPउपका
1.691313.
12.539998
10.266278
..192492
6.373177
4.834271
उ.376646
2.501951
I.019378
1.251041
.841530
.552999
.उमरण
.223297
.137344
.082707
.048782
.028193
.015072
.008874
.004837
.002588
.001359
,000701
1001
.000177
to Axts of 2" x 2" diam Cylinder ut NE-21% Scintillatur.
"Cubalt" Units) for Plane Pirallel l-klenergetic Neutras perpendicular
Table IV. Absolute Differentiul Erriciency is i Function of Light Output (in
4.620362
4.138449
4,8569.9
4.955066
5.050426
कारणाप
.100289
3.041630
4.916975
4,723403
4.452692
कार
3.753244
2.547575
2.550580
2.560354
2.576849
2.599884
2.हर
2.663686
2.702888
2.745131
2.788239
2.829131
उठा
2.0.7833
।.135643
PULSE HEIGHT
0.335 MEV
0.6 MEV
0.945 MEV
1.25 MEV
1.56 MEV
1,91 MEV
100
.1047
. 1094
114,
.1252
1259
TUTT
. 13 An
00017
,00n042
,000020
,00nong
000014
Oonon2
UULUT
Bonono
J30072
1926012
2,469009
2,063607
1,665329
1. 305661
T1276717
1.121541
To! 17303
TIT03375
1.720396
1.141418
1.765517
1.791066
1,815792
...
TITUT20
072124
042941
024930
016114
007793
TUUTT97
002205
001200
000657
000252
000099
1000030
000009
000003
000001
.000000
1000000
,73306
537305
39049,
.257323
.137113
09023
,040456
024215
0111.6
004769
,00 1041
TUUSTU
,000205
0000,0
1000015
,0000913
,000011
,000000
.1314
. 15.5
. 1669
131
. 1821
. 1905
. 1995
. 2009
.216
.220T
.2399
.2512
.2631
.2754
.2814
.3070
.3162
.33 11
.3467
.3631
.3802
39.
. 4169
.4365
.4571
.47.6
.5012
.370
.5495
.5754
.6026
.6310
.6607
.691
.7244
.7566
.7943
.6316
..7in
9121
.955
2.606776
2.6:4310
2.640354
2.715422
2.693655
2.72166
साया
2.241606
2.750043
1.59666
1.639770
T307517
To 5204T
0913930
694004
301612
. 343086
4220726
on 2139
074127
038172
017992
007701
002966
.001021
000311
0000.3
.000019
000004
000001
UUUUU
000000
1.851211
1.852392
1.840009
1,826123
1.796034
1,750415
1,585757
1.602101
1,498660
1.374545
1.229295
1.77T26
.883568
.696489
.315449
354067
.223174
,127629
,065494
029811
011930
004144
,001237
Tol14307
Tol15665
TOMTOTTU
1125100
1.130858
Tol331 88
T.145141
T.156965
TiT 13650
T.167479
To198227
1. 203364
1.200439
1.167546
To T73667
T120719
T.083333
10:20 100
9.62332
.804474
.791730
.682367
556214
, 426525
.299316
169666
No109
052563
022275
008006
,002 405
000595
00012
000019
000002
.000000
.000000
Table IV (continued)
N00067
,000012
000002
,000000
,000000
ooooooooooooooooobooooobo
oooo poooooooooo po

PUI SE HEIGHT
2.98 ५EV
3.96 MEV
5
.91
v
.12 MEV
||.O MEV
14,4 MEV
-
-
•0100
AAM
.0105
.0110
.0115
.0120
.0126
उर
.0139
.0145
.0151
.015.
.0166
.017
.0182
.0191
.0200
.0209
.0219
.0220
.0240
.0251
.0263
.0275
.028A
.0307
.0316
.0331
.0347
.0363
.0380
उपा
.0417
.0437
.0457
5.05496
4.379364
3.808562
3.325225
2.916396
2.573126
2.रहमा
2.044095
1.843677
।.677127
1.539189
1.425319
T.31843
1255718
I.194271
1145007
I.105559
1.073710
TU7502
1.025378
I.005963
.988508
.072324
.956879
741730
.926405
.91863
.894513
.877529
.859992
3.216060
4.963168
4.636828
4.271771
3.882246
3.483846
Jणयह
2.717697
2.372215
2.061361
।.780447
।.5542।।
T.357360
1.195171
1.063856
.959089
876335
1811202
175079
.718519
.681931
.656959
.633193
.612675
.594769
.577066
.565286
.553210
.542634
.533332
1570वण
.517498
.510391
1503454
406452
.489201
हामाश
.731702
5,403548
4,973373
4.1149
4,036611
उ737017
3.1177.3
2.100368
2.322592
1988278
1698231
1,5ाण
1,243446
1.071576
93081
.8165.6
.१24581
6505
91400
,343984
.595773
47495
449829
429097
11690
.396758
.39369
37|
.351103
:
2.667461
2.528069
2.398176
2.278579
2.170081
2.072741
TOP852
।.905149
।.828820
।.752593
1.673262
1.586686
व0019
1.401019
1.301383
1.198585
1.095358
.993368
83917
.717962
.706238
.619398
.530।।।
.463071
.394073
.334426
.281870
.237510
.201285
172887
रागा
.137301
.128608
.124825
•125028
.128301
133778
.140691
-
6. 9076
5.712537
5.345988
4.032101
4.487733
4,030640
3.5773
3,143207
2.737316
2.366639
2.034263
1.740604
।.434205
1.262502
1.072405
.010662
.714109
.659766
.564076
486902
.423524
.372607
.332203
.300532
215995
.2,784
,242881
.232055
.223846
.217550
•7259
.200513
.204958
.201666
198458
195223
1907
108431
104952
181313
।77563
173706
•69750
155719
.61660
17646
153772
.150137
16630
.14391।
-
4.47613
4.335658
4.176313
4.005106
3.829138
3.653869
उपहार
3.312592
3.142867
2.968260
2.784460
2.588600
2.380061
2,160802
1.934960
।.708150
।.486576
1.276121
1081685
.906751
.753272
.621769
.511575
.421156
.340453
.29।।77
.247038
.213914
.।89948
173585
Ti567
158879
158718
• 162395
.169288
178798
190328
.203273
.217026
.230987
.244570
.251214
.26
.277612
.284462
.280609
.289846
.288116
.263527
.276338
-10-
(Pari:: :'! '.) 1
-
-
1431587
1473559
.465135
.456380
.0501
.0525
.0550
.0575
.0603
.0631
.0661
.0697
.0724
.0750
.0794
.0832
.0871
पार
.0955
.822404
.802012
.783177
.763435
.743950
725012
.706930
.689535
.673536
.658570
.644714
सामम
.619983
.608897
.5985।।
.538700
.570319
15711
.56।।47
.341995
1333292
,325000
.31719
'.309742
1302649
.205852
.299300
.232958
276738
.290715
रा15
.256800
253056
.247282
.241450
.235615
17TT
2237.5
.438433
राग
.420762
412260
.403992
.305908
.3,7915
13793
.371885
.156463
.164509
.172312
17660
186305
.191912
.196066
.198313.
.198250
1963
190372
PUL SE HEIGHT
2.94 MEV
3.96 MEV
5,97 MEV
0.12 MEV
I 100 MEV
14,4 MEV
100
.1047
.1096
3I
.542780
.533448
.524224
.515409
.507332
.5002741
.494379
.489074
.483452
.479974
.476990
A
.1202
.1250
.
IN
.13an
1445
.1510
.1585
.1660
.T7W
.1820
.1905
.1995
.2089
.2188
.2201
.2399
.2512
.2630
.2754
.2884
.
.3162
.33।।
.3467
.3631
.3802
.30
.4169
.4365
.4571
.4786
.5012
बर
.5495
.5750
.6026
.63in
.6607
.
.7244
.7584
.7943
8318
.870
.470857
.467075
.462703
.457939
.453163
48818
.445320
.442051
.441792
.441703
.442349
पटक
.444320
.445263
.446292
.447494
.448531
.440387
-51-
उस
.355621
.347539
.339654
.332117
.325055
5700
.312715
.307339
-302098
.297007
.294044
1290701
.287635
.284601
.281705
.278552
.275170
1271570
.267827
.264049
.260336
.256801
.233606
.25ाण
.249391
.249051
.250140
.252470
1255491
•256371
.260217
.260414
.258990
.256722
.254792
गा
1255390
.258302
.262226
.265759
.266994
1261266
.256943
,245772
.2327 ।।
.220072
209046
267
183126
गण
211403
.205211
129122
103296
137707
2523
177605
173136
150848
164539
160299
पण
151500
147013
142715
138706
135348
T
130539
129125
128096
.127181
,125869
रासाय
12107
।।9456
।।1104
115198
।।3635
112466
।।।।।।।
.109224
,106724
.103813
101149
.09
079044
.100293
102371
104441
105839
139241
.137360
.135625
133892
132030
.2947
127596
125009
.122320
.।19655
17068
.
IN00
..।।2935
11738
.।।।192
.।।।151
.।।1288
•ITTET
.| 10348
.108574
15851
102471
.098901
.
01
.092946
.070998
.089681
.088768
.088001
.087157
.006088
.094721
.083040
.091064
.078038
.
00
.074020
.071762
.069779
.068052
.066445
बाण
.062779
.060642
.098739
.057527
.056528
75200
.03484
.266
.255723
.243178
.229706
.215613
.201412
.187242
173489
161169
.150827
139531
129632
•ा2737
.।।4727
.109716
106043
• 103294
.100953
098459
.095289
.091046
1185552
078933
.071630
.060
.057678
.052265
.048310
.045769
.044417
.043940
.043982
.044180
.044222
.043925
.043264
वराज
.041168
.039935
.038734
.037753
.036946
उ6226
.035509
.034858
.034427
.034283
,034331
कम
.034564
गा
173207
.162430
.15:194
-140305
•130504
•122406
•।16463
.112934
110992
।।। 052
.113539
.13205
124624
.132195
.140150
.147502
.153517
15707
.157470
.154562
.148512
140000
129964
साह
.109113
.099744
.091645
.084960
.079640
.075455
.072014
.068854
.065594
.062105
.058539
10ाण
.052115
.049373
.046880
.044738
• 043154
बर723
.041719
.041020
.039262
.035885
•031274
.026715
.023401
Ta',le IV (.walimuta)
900
0Nm
438210
.425635
.400002
.387336
उ666
.340392
.335759
.325524
.3।1440
.29017
मारण
187183
.।।9220
.061445
.024586
.007424
.001565
.000265
10681
106438
104029
102410
,099507
100
0327
300 C
पाशा
.9550
PULSE HEIGHT
MEV
3,96 MEV
5.09 MBV
6.12 MEV
.11.0 MEV
...14.4 MEV
.
IN
__
WOUJU
.000002
.000000
051166
:
01
Iulia
151736
oli 5950
.061606
030322
1009375
.001 925
0002,
.000020
00000 1
,000000
702TUU
020472
019729 **
019120
010677
010176
05136.
031614
051610
UT116
005071
098573
090376
100232
102444
mur
10.716
112052
. 109917
102663
098976
TUW030
,090446
073275
,034300
027399
,000237
TUOT379
000112
,000004
000010
,000000
050394
030037
052007
5052913
052006
052362
051944
6031960
032292
032148
031440
020779
030040
TOVOU
1.0471
1.0965
. 1462
1.2023
1.25.9
T.JUS
1.3804
1.4454
1.5136
13649
1.6596
TN70
1.8197
1.9055
1.9953
2.0893
2.1871
2.2009
2.396.
2.5119
2.6303
2.7542
2.0040
3.0200
3.1623
3.3113
3.4674
3.6316
3.8019
J, YUTT
A.1607
4.3632
4.5709
4.7003
5.0119
5.2701
5.4954
1.7544
6.0296
6.3096
6.6069
. TOS
7.2444
7.5656
1.9433
8.3176
8.7096
On
9.5499
TU39763
034926
,034660
,034522
..034036
033502
TUNUCU
,032685
032270
031520
030665
03005.
,029635
029055
,026134
027366
,026921
, 026 486
1025093
,026049
,026546
026307
025799
026047
026973
,027651
027149
026439
,025951
. 025835
023905
,024219
1021 104
014496
,004910
,000506
1000011
,000000
-32-
047610
045640
039193
024551
008470
.001238
000063
.000001
.000000
017321
017444
017392
017299
017396
017132
010036
017906
017134
016140
013641
015767
015653
015394
015327
015584
015669
015165
.014512
014237
.014107
014303
01 4561
UT1992
015249
014926
014699
015365
014969
101439A
014036
013176
012389
.01 1938
007941
01900
000102
000001
.000000
Taile IV (continued)
Oo OoopooOoop ooooo
oo
OO
PULSE HEIGHT
0.2 MEV
0.4 MEV
0.6 MEY
0.8 MEY
1.0 MEY
1.25 MEY
1.5 MEV
2.0 MEV
3,300103
3.237159
3,180504
3, 129392
3.082861
3.040052
3,000212
2.962682
2,926921
2,892491
2.859038
2,826318
2,79710
2.762549
2,731 436
2,700872
2,670964
2,641837
2.613653
2.586569
2.560749
2.536361
0100
.0105
.0110
. 0115
0120
.0126
01322
.0136
.0145
0151
.0158
.0166
0171
. 0182
0191
.0200
.0209
0219
0229
.0240
.0251
.0263
.0275
.0200
0302
0316
0331
.0347
.0363
.0360
. 0390
.0417
.0437
0457
0479
.0501
.0-25
0550
.0575
.0303
0631
.0661
. 0692
.0724
.0759
0794
.0832
.0871
0012
.0955
2, 2017
53,628049
52,838442
51,777779
50.453273
46.876949
77,065410
45,0383 n 1
42.820428
40, 439375
37,925822
35, 313031
32,636076
29.930433
27.231926
24.574574
21.990343
19.508140
TT,153076
14,9455 28
12.901474
11.0312.2
9,340957
7.831403
1.799975
3.339444
4,340432
3.490 9n5
2.777301
2.1855n1
T, 100015
1,308356
,995025
.7479,8
.555532
.407610
•295513
,211547
149514
. 104473
.071926
0489n1
7032073
.021708
.014186
.009118
005713
00368
1002230
.001354
12.104256
12.979660
13.902951
14.950671
16.146694
17.461860
10.89 1220
20.414 888
22.005336
23.627295
25.238617
26.792794
28.230527
29.524598
30.60 1097
31,422592
31.950967
32.157479
32.024695
31.547649
30.734206
29.604518
26.190774
20.533772
24.681639
22.687205
20.604923
18.486301
16.387436
14.347 195
12.405549
10.592659
8.930649
7.433477
6.107634
4.952928
3.963611
3.129608
2.437710
1.872781
1.418799
1.059732
1700225
.566! Us
404696
.284978
. 197625
. 134930
.090679
.059967
6.396291
6.430176
6.473751
6.530133
6.600913
6.688289
6,795040
6.924573
7.080892
7.268637
7.492901
7.759201
8.073224
8.440613
0.866596
9.355478
9.910236
10.531834
11.218557
11.965339
12.763212
13.598625
14.453366
15.304424
16.124379
16.882432
17.545551
16.080482
18.455635
18.643653
10.623315
18.381714
17.915420
17.231497
16,3471 48
15.286962
14.091298
12.793430
11.437734
10.066396
8.718906
7.429969
6.227877
5.133517
4.160179
3.313836
2.594042
1.995046
1,507173
1118170
6.284911
0.103115
7.927306
7.750 103
1.595A06
1.440601
7.292929
7.1531 45
7.021647
6.898455
6.785330
6.661747
6,380962
6.508062
6.440506
6.367943
6.352519
6.336873
6.344100
6.377A31
6.442 152
6.541525
6.680639
6.86401
7.095863
7.378567
7.71407*
8. in 1175
8,535913
9.010793
9.514413
10.031272
10.542073
11.024401
11.453626
11.804402
12.052441
12.176066
12. i 58246
11.9A7980
11.661650
11. 183612
10.503912
9,827929
8.994893
8.096004
7.162852
6.226170
5.TROT
4.453465
6.065440
5.97 A640
5.872797
5.767797
5.663684
5.560630
5.451936
5.358954
5.261117
5.165912
5.073831
4.985386
1.90 1097
4,821509
4.747161
4.678558
4.816236
4.560779
4.512609
4.473053
4.442352
4.421736
4,412544
4.416335
4, 435045
4.470993
4.526859
0.605651
4.710543
4.844802
5.0 I 1365
5.212619
5.449861
5.723030
6.029992
6.36357
6.725150
7.096660
7.468597
7,626453
A. 154137
R. 434726
8.657312
8.760930
8.033709
6,776149
8.610314
R.335236
7.955015
7.47A636
3,650575
3.60 376
3.558828
3.515264
3,475 114
3.437914
3,403259
3,370154
3.340450
3.311860
3.204952
3,25962A
3.235A25
3,213527
3.192729
3.173416
3,155601
3.139323
3.124604
3.11 1494
3.100066
3.090431
3.0A2783
3.077344
3.074440
3.074511
3.078130
3.0A5986
3.008946
3.11 6071
5. i 2612
3. 179963
3.225769
3.283885
3.336209
3.444AON
3,551649
3,678570
3.826900
3.997625
4,190347
4,403713
7,634747
4.678665
5. 128815
5.376727
5.612315
5,824317
6,000991
6.130812
2.492516
2.473330
2.456134
2.441035
2.428108
2.417447
2.409134
2.403272
2.399971
2.399413
2.4U 1862
2.407676
2.417369
2.431633
2.451331
2.477559
2,511597
2,554918
2.609126
2,67587
2.756519
2.852 483
2.964490
3.092659
3.236130
3.392923
3.559746
2.622515
2.543560
2.473500
2.411565
2.356563
2.307741
2.27337
2.225671
2. ISI 104
2.160076
2.132063
2. 106565
2.003210
2.061589
2.041343
2.072181
2.0038 40
1.966109
1.968 IT
1.95 1 200
1.934991
1.918264
1.901661
1.8e5n81
1.868534
1.852021
1.8:5553
1.819123
1.802744
1.726434
1.71021T
1.75 4095
1.7:8137
1.722396
1.706955
1.681521
1,677432
1.663646
1.650745
1.638932
1,628430
1.619498
1,612382
1.6C7305
1,684@37
1.66.5111
1.608459
1.616002
7,627770
1.644690
-33-
to Axes of 5" x 5" diam Cylinder of NE-213 Scintillator.
"Cobalt" Units) for Plane Parallel Monuenergetic Neutrons Parallel to
Table v. Absolute Differential Efficiency as a Function of Light Output (in
V
PULSE HEIGHT
0.2 MEV
0.4 MEV
0.6 MEV
0.8 MEV
I.O MEV
1.25 MEY
1.5 MEY

2.0 NEV
-
.1000
1041
.1096.
1202
1259
.
.
.
.000010
.000477
.000277
.00018
.000089
.000049
.000027
.000014
.000008
.000005
.000002
.000001
.000000
.039014
.024966
.015706
.009713
.005903
.003525
.002067
.001190
.000729
.000439
.000194
.000081
.000032
.000012
.000004
.000002
.000000
.000000
.814496
.582374
.408642
.201320
189961
.125781
.001646
.051940
.034360
.022778
.012076
.006116
.002952
.001354
.000539
,000242
.000094
.000034
.000012
.000004
.000001
.000000
.000000
3.661660
2.952963
2.334909
1.819473
1.373874
I.021645
.743805
.529996
.385372
.282786
.178293
.107916
.062552
.034632
.010265
.009150
.004342
.001946
.0001
.000325
.000120
.000042
.000013
.000001
-
1380
1445
1514
.1585
.1660
TI
.1020
1905
.1995
.2009
.2188
.2291
.2399
.2512
.2630
.2754
.2884
.9020
.3162
.33।।
.3467
.3631
.3802
.3981
4169
.4365
.4571
.4786
.5012
.5240
.5495
.5754
.6026
.6310
.6607
.6918
.7244
.7586
.7943
..310
..710
.120
.9:50
6.920716
6.298556
5.633172
4.946978
4.262477
3.600601
2.979530
2.113576
1.961386
1.605004
1.190566
.865907
.602031
.401976
.256960
.156746
..90928
.040981
.125033
.012651
.005770
.002461
.000973
.000356
.00120
.000037
.000010
.000003
.000001
6.203417
6.210235
6.145285
6.005671
5.791953
5.507988
5.160978
4.761000
4.359473
3.990010
3.520846
3.039296
2.561360
2. 102640
1.677131
1.296221
.96780
.695788
.479970
.316499
.1987।।
110288
.066467
.035001
.017322
.007954
.003379
.001321
.000472
.000154
.000045
.000012
.000003
.000000
.000000
.000000
3.36
3.903408
4.066998
4.214616
4,337875
4,428504
क.479030
4,483312
4,432482
4,349096
4.235084
4.067195
उ7070
3,579002
3.269746
2.928215
2,565104
2,192461
T.823071
।,469718
1,144311
.826766
.613967
418986
127063
104893
.094004
.049874
.024470
.011029
.004536
.001690
.000566
.000169
.000045
.000011
.000002
.000000
.000000
.000000
1.667600
1.657403
I.715010
1.78812
I.836957
'.962304
1.07700
2.06080
2.115605
2.194046
2.200042
2.388438
2.
46
2.569660
2.642512
2.665634
2.723460
2.731410
२.एक
2.617500
2.515643
2.383642
2.235512
2.045634
1.840128
1.636670
1.414888
1.107350
.960499
.742925
.544502
.374787
.239851
.14150
.075977
.036879
.016007
.006151
.002072
.000605
.000152
.000032
.000000
.00000
.000000
.000000



Tubie V (continued)
-34-
-०००००००००००००००००००००००००००००



००००००००००००००


००
PULSE WEIGHT
3,OMEv
4.0 MEY
5.O MEV
7.0 MEV
9.0 MEV
11.O MEV
14,
MEV
....
-35-
.0100
.0105
.0110
.0115
.0120
.0126
.0132
.0138
.0145
.0151
.0150
.0166
017
.0182
.0191
.0200
.0209
.0210
.0220
.0240
.0251
.0263
.0275
.0288
.0302
.0316
.0331
.0347
.0363
,0380
.0398
.0417
.0437
.0457
0479
.0501
.0525
.0550
.0575
.0603
.0631
.0661
.0692
.0724
.0759
.0794
.0832
.0871
1.5206
6.287138
6,059294
5,837004
5,620022
5,408128
5.2010K2
4.998619
4,800605
4,606934
4,417566
4,232569
ब,052000
3.876332
3.705505
3,540153
3,380321
3,226413
उ,078712
2.937433
2.802754
2,674720
2.553571
2,439102
2,331315
2,230038
2,135266
2.046666
।.964057
1,887192
।.815000
1.749567
1688142
1.631108
1.5783.9
।.529118
।.4832।।.
1,44017
।,399671
।.361326
।.324045
।.289902
1.256574
1.224450
1.193548
।।63831
1.13534
I108034
5.276792
4.930137
4.606351
4.305068
4.025585
3.766995
3.528158
3.307836
3.104717
2.917447
2.744713
2.505253
2.437873
2.3015।।
2.175179
2.057994
1.949180
1.848064
1.754038
1.666572
।.585185
।.509454
1.439004
1.373488
।.312584
1.256007
1.203491
1.154790
I.109668
I.067913
1.0293ाव
.993663
.960762
.930418
.902433
.876623
.852813
.830826
.810506
.791708
.774298
.758158
.743170
.729222
.716204
.704002
.692510
.601609
3.362100
3.075785
2.812717
2.572575
2.354637
2.157958
।.981306
1.823631
1.683298
1.558931
1.449072
1.352259
1.267100
1.192260
1.126505
1.068686
1.017773
.972848
.933102
.897832
.866435
.838396
.813287
.790744
.770462
.752175
.735660
.720707
.707126
.694730
.683332
.672746
.662778
.653243
.643957
.634750
.625475
.616009
.605267
.596206
.585820
.575155
.564284
.553314
.542369
.531583
.521087
.510986
उ.रा857
2.953371
2.708688
2.480819
2.269610
2.074818
1.896025
1.132734
I.584353
1.450197
I.329523
1.221530
I.12534
I.040193
.965099
.899195
.641597
.701420
.747841
.710024
.617195
.648636
.623686
.601747
.582291
.564864
.549087
.534647
.521302
.508869
.407220
.486267
.475956
.466262
.457173
.448692
.440819
.433556
.426900
.420840
.415356
.410423
.405909
.402039
.398484
.395277
.392355
.389645
8.770049
8.343783
7.195670
7.437466
6.973054
6.506583
6.042143
5.583763
5.135231
4.700056
4.281353
3.881852
3.503709)
3,148937
2.818584
2.513506
2.234056
1.980140
।.751206
1.546678
1.365215
1.205566
!.066225
.945564
.041662
.753454
.678569
.615571
.562876
.519013
.482622
.452479
.427493
.406712
.389318
.374623
.362062
.35।।72
.341591
.333043
.325314
.318254
.311748
.305710
.300077
.294792
.289806
.205062
7.633716
7.491297
7.334204
7.160890
6.970036
6.760799
6.532764
6.286052
6.021407
5.740160
5.444237
5.136142
4.616868
4.4958।।
4.170633
3.847060
3.528857
3.219601
2.922591
2.640687
2.376266
2.13|150
1.906575
1.703186
1.521069
I.359812
1.218557
1.096095
.990941
.901440
.825844
.762374
.70930
.665020
.528008
.596931
.570613
.548036
.528347
.510819
.194886
.480083
.466067
.452513
439290
.426256
.413350
.400548
1,270735
5.892850
5.590427
5.3022।।
5.026839
4.763016
ब,50947
4,264951
4,028404
3.798857
3.575518
3.357763
उकाठण
2,937520
2.734809
2.537155
2.344882
2.158455
19761
1.805540
1.640420
1.463812
।.336432
1,198914
1.0701
.955547
.850415
756540
673874
1602205
.547152
490185
.448646
415766
.390692
.372517
360208
.393076
.349898
.349829
.351965
.355447
.35972
.363310
.366321
.367982
.367897
.365820
Table V (culitinued)

.
11
:
:
20F2
993
P
ORNL
UNCLASSIFIED

.
.
.
..
.
...
in.c...
...
***.,*****
LL
.
1
+
1."',"19






PULSE HEIGHT
3.0 MEV
4.0 MEY
5.0 MEY
7.0 MEV
9.0 MEV
11.0 MEY
14,4 MEV
.651412
.64 1002
T.034372
T0128;
,99296
.9749 na
.958718
7932277
, 922123
19125n9
,902410
.897237
89lio
, 1000
,1047
in96
. 1148
. 1202
•1259
1318
. 1380
1445
151
: 1585
. 1660
. 1730
1820
1905
. 1995
.2089
.2188
.2291
.2399
.2512
.2630
.2754
.2884
.3020
. 3162
.3311
.3467
.623413
.614420
.605620
.597059
.588 ANO
580261
.571385
.564278
.557712
.551771
.546522
.542017
.538 264
.535242
.532906
.531200
. 530082
.529561
.529688
.530556
.532250
.534816
.538233
.542439
.547398
.553155
.559901
.567932
.577576
.5A 9073
.602489
.617683
.634 330
.651915
.669681
.686434
.700348
.706905
.709202
.696667
.676036
.642225
.600400
.554844
.508664
. 461130
. 400530
,463711
, 475641
.467979
. 400612
. 453409
. 446236
,038991
.43 1602
,423612
. 415765
.406239
.400710
393340
.386292
.379755
.373871
. 368706
.364240
.360369
.356927
.353749
.350691
.347691
.344771
.34 2046
,339711
.338011
. 337211
. 337450
.33A921
.341426
.344723
. 348450
.352278
. 356038
.359779
.363719
. 368119
.373 148
.376978
.385700
.393656
1403323
.415070
.428744
.443357
.457156
.468107
. 474400
.474452
,892978
.893725
396239
,9004nl
9C6125
.913415
922448
,933477
946974
,983447
1983773
1.007959
Ti036070
1,067284
T.100019
Til31931
1,100U3
T. 180921
1.191316
T, 188393
T170178
1,1362-7
1,087875
1027427
7958321
883042
802055
,713174
,613043
,500913
,381351
,205051
164923
090273
042050
.017148
005771
0016 no
. 382102
.379555
,376883
.374025
.370931
.367548
.363836
.359763
.354895
.349419
.344539
.339245
.333541
.327440
,320968
.314156
.307036
.29964
.292007
.284148
.2760?1
.267861
.259502
.251087
.242739
.234591
.226874
.219798
.213553
.218236
. 203806
.200046
.196637
193257
. TA9 703
.18597
.182247
, 178779
.175792
.173430
. 171797
.171037
.171333
.172771
.175119
. 177759
.179904
.181035
.181193
.TA0921
.221770
. 267512
.?63275
.259057
.254870
250736
.246690
.242769
.238806
.234759
.231324
.22A009
.225101
.222335
.219808
.217530
.215517
.213796
.212392
.211320
.217566
,210090
.209817
.209667
1209573
.200515
.209470
.209505
.200645
.209877
.210102
.210114
.209599
.2012 18
.205845
.201795
. 196793
191034
, 185058
. 17937!
174216
. 169446
.1045AO
,159089
152728
. 145701
.138543
. 131858
126069
,121218
,362959
350797
33081
327069
315440
33886
.292338
.280734
269662
.259338
.247691
236020
.224437
,213115
,202279
. 192174
.183030
.!75026
168246
• 162670
. 158171
. 154552
.151587
149077
.146884
,144 943
. 143236
.141762
, 140490
139354
138269
.137163 ..
, 13598R
.1347 in
133264
131526
.129336
. 126577
. 123281
119677
. 116125
112961
ill0321
. 108097
. 106647
103986
C1920
10001
.088415
.097096
377567
334221
327949
.317302
306883
.297292
7209097
282301
.278441
,215093
.274557
.276767
201728
289226
.296817
349821
.321 335
. 332290
341530
.347927
.350523
.349652
,342159
.330839
.315924
.297997
.278334
.258136
.238450
.220079
20348 U
. 108861
.170246
. 165573
.156733
149552
143734
138859
134 467
130226
, 12603
122022
ol18219
oll 4314
. TV9479
102705
093524
082611
101 1669
062523
-360
Table V (CC.bitirutd)
. 3A02
. 3981
,4169
. 4365
.4571
. 4786
5012
,5248
.5495
.5754
, 0026
.6310
.6607
0918
.7244
.7586
, 7943
.8318
.8710
, 9120
.955
NNN
9
PULSE HEIGHT
3.0 MEV
4.0 MEY
5.0 MEV
.
7.0.KEY.
20 MEN
11.0 MEY ... 14,4 MEV
7000359
000004
0000n9
00001
0000nC
00000
13213905
. 265642
181719
105938
105 1033
.019739
003979
.001366
.000240
.000030
000003
.000000
.000000
.000000
,466302
,449350
.423011
.390694
.357271
325940
297037
, 256817
:204807
.141150
.079316
,034559
011166
.002568
1000404
.000042
.000003
.000000
.000000
T0000
1.0471
1.0963
1, 1402
1, 2023
1.2589
TJOY
1.3804
1.4454
1.5136
1.5849
1.6596
T.7370
1.6197
1.9055
1.9053
2.0093
2.1876
2.2009
2.3988
2.5119
2.6303
2.7542
2.8840
U70200
3. 1623
3.3113
3.4674
3.6308
3.8019
3.96
4.1687
4.3652
4.5709
4.7863
5.0119
5.2481
5.4954
5.7544
6.0256
6.3096
6.6069
6. 9183
7.2444
7.5858
7.9433
8.3176
8.7096
9. 1201
9.5499
.100917
161985
184630
109296
94966
.201542
.21.567
.216271
224427
,231881
.237161.
236567
.23JAJO
221665
207426
1 86761
i171628
. 157803
730200
103959
.059096
.022644
.003343
.000722
.000053
.000002
.000000
116063
112305
,107231
102220
090390
.098413
n95000
095994
,096477
.897669
n99941
102968
106106
109460
,113315
117926
,122225
,124763
.125323
,125257
.123351
118431
111667
. 105432
.199766
191397
on 76897
.051596
.n23024
005874
.000709
.0010 47
100001
.n00000
7093007
094669
093453
092148
090323
,087542
.084003
.000964
.079028
077911
076722
074695
1072414
.069611
.067135
,065672
065421
066151
057623
,069737
.072 118
.074164
.075116
. 076967
.07617
.080021
.08! 277
080881
.075969
.069988
.065006
,060323
052627
,035993
.014899
.002971
.000239
.000007
-37-
7056702
,052106
,049509
0047356
,045316
043657
02776
042695
043136
043458
043878
044209
017292
044151
043794
.043005
041899
041 162
01200
041008
041755
041301
040079
038449
10.7572
.037688
037835
0 $7574
,037425
038112
CJ9901
041569
042687
044579
046333
046458
071362
040697
038186
.036890
033154
021337
000444
.000843
.000030
.000000
.000000
oooooooooooooooooooooooooooo
oooooooooooooooo
ocooooooooo
-36.
the right hand edge of the pulse height distribution, when plotted on a
semilog scale (lue counts vs linear channel number).
This definition of resolution is somewhat deceiving in that the stil-
bene curves slowly roll off before settling down to a straight-line drop-
off. From 2.85 MeV data, the resolution values are poorer and much closer
together due to photomultiplier-stritistics limitations, being about 14%
for stilbene and 16% for NE-213 (1" x 1" to 2" x 2").
The smaller scin-
tillators have a somewhat sharper edge because of reduced multiple neutron
scattering in the scintillator, but cne obtains a small gain in resolution
for the price of a large loss in detector efficiency. A good compromise
is the 13" x 15" NE-213 scintillater placed in a la diam x 2" high
S
aluminum reflector. The photom.ltiplier should then have a photocathode
area no smaller than that of the 2"
RCA 68.10A photomultiplier tube.
VIII. FUTURE WORK
The response functions are being extended to neutron energies of
25-30 MeV by including (n,p) and (n, pn) reactions whose cross sections
become important above 15 MeV. Also, leakage of recoil protons from the
scintillator (especially the small, high resolution scintillator) becomes
important above about 10-15 MeV, and depends on scintillator size. A
14 MeV recoil proton has a range of abcut 5 cm in NE-213. The 05R program
used in this work is being modified to include 12c(n, p)??B una 12c(n, çn)72B
reactions and proton leakage.
-39-
ACKNOWLEDGMENTS
The authors wish to express their appreciation to F. C. Maienschein,
R. W. Peelle, and C. E. Clifford f'or their helpful discussions and interest
in this project. The calculations could not have been performed without
the help of J. G. Sullivan, R. E. Textor, R. E. Maerker, and F. B. K. Kam.
The earlier proton recoil measurements were aided by F. J. Muckenthaler
and K. M. Herry.
The associated particie experiments owed their success
to R. W. Peelle, R. T. Santoro, and N. W. Hill.
-40-
REFERENCES
1. Manufactured by Nuclear Enterprises, Ltd., Winnepeg, Manitoba, Canada.
2.
J. B. Marion and J. L. Fowler (eds.), Fast Neutron Physics, p. 228
Part I, vol. IV, Interscience Publishers, Inc., New York, 1960.
3. R. R. Coveyou, J. G. Sullivan, and H. P. Carter, Neutron Phys, Div.
Ann. Progr. Rept. Sept. 1, 1962, ORNL-2609, p. 87.
4. M. Kalos and H. Goldstein, Neutron Cross Section Data for Carbon,
NDA 12-16, (March 31, 1956.).
5. V. V. Verbinski et al., Neutron Phys. Div, Ann. Progr. Rept. Sept. 1,
1962, ORNL-3360, p. 105.
6.
See, for example, R. J. Kurz, A 709/7090 Fortran II Program to Compute
the Neutron-Detect Efficiency of Plastic Scintillators for Neutron
Energies from 1 to 300 MeV, UCRL-11339, University of California,
Lawrence Radiation Laboratory, (March, 1964).
7.
8.
K. F. Flynn et al., Nucl. inst. Methods 27, 13 (1964).
J. B. Birks, Proc. Phys. Soc., A64, 874 (1951).
9. W. Whaling, Handbuch der Physik, vol. XXXIV, p. 193, Springer Verlag
(1958).
P. 3. Schambra, A. M. Rauth, and L. C. Northcliffe, Phys. Rev. 120,
1758 (1963).
P. G. Roll and F. E. Steigert, Nucl. Phys. 17, 54 (1960).
M. S. Livingston and H. A. Bethe, Rev. Mod. Phys. 9, 246 (1937).
13. R. Batchel.or et al., Nucl. Inst. Methods 13, 70 (1961).
14. 1. C. Northcliffe, Ann. Rev. Nucl. Sci. 13, 67 (1963).
15. M. F. Steuer and B. E. Wenzel, Bull. AFS 2, 605, G 11 (1962).
16. M. L. Chatterjee and B. Ser, Nucl. «Phys. 51, 583 (1964).
.
.
<
DATE FILMED
4 / 1 / 65




-
.-
-
..
.
LEGAL NOTICE -

-
This report was prepared as an account of Government sponsored work. Neither the United
States, nor the Commission, nor any person acting on behalf of the Commission:
A. Makes any warranty or representation, expressed or implied, with respect to the accu-
racy, completeness, or usefulness of the information contained in this report, or that the use
of any information, apparatus, method. or process disclosed in this report may not infringe
privately owned rights; or
B. Argumes any liabilities with respect .. the use of, or for damages resulting from the
use of any information, apparatus, method, or process disclosed in this report.
As used in the above, "person acting on behalf of the Commission" includes ary em-
ployee or contractor of the Commission, or employee of such contractor, to the extent that
such employee or contractor of the Commission, or employee of such contractor prepares,
disseminates, or provides access to, any information pursuant to his employment or contract
with the Commission, or his employment with such contractor.
...
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END
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