Contribution to the International Workshop on Fast Neutron Physics, held September 5 - 7, 2002 at Dresden, Germany.

 

Monoenergetic neutron sources based on two-body reactions

M. DROSG

Institut für Experimentalphysik, University of Vienna,

A-1090 Wien, AUSTRIA

Abstract

The code DROSG-2000 is presented which calculates the kinematic, cross section and yield data of, presently, 59 monoenergetic neutron source reactions based on the following two-body reactions: 3H(p,n)3He, 6Li(p,n)6Be, 7Li(p,n)7Be, 9Be(p,n)9B, 10Be(p,n)10B, 10B(p,n)10C, 11B(p,n)11C, 12C(p,n)12N, 13C(p,n)13N, 14C(p,n)14N, 15N(p,n)15O, 18O(p,n)18F, 36Cl(p,n)36Ar, 39Ar(p,n)39K, 59Co(p,n)59Ni, 2H(d,n)3He, 3H(d,n)4He, 7Li(d,n)8Be, 9Be(d,n)10B, 11B(d,n)12C, 13C(d,n)14N, 14N(d,n)15O, 15N(d,n)16O, 18O(d,n)19F, 20Ne(d,n)21Na, 24Mg(d,n)25Al, 28Si(d,n)29P, 32S(d,n)33Cl, 3H(4He,n)6Li, 7Li(4He,n)10B, 11B(4He,n)14N, 13C(4He,n)16O and 22Ne(4He,n)25Mg, using either the light or the heavy particle of the entrance channel as a projectile. In the (p,n) case the use of the heavy particle as a projectile results in a strong enhancement of the forward neutron yield due to kinematic collimation of the neutrons into a forward cone. In addition, near-threshold neutron production and other more recent trends are discussed.

1. Predictions of monoenergetic neutron source properties

Since 1987 a computer code package originally called DROSG-87 has been available to calculate the salient properties (laboratory and center-of-mass angles, cross sections, energies, yields) for neutron sources based on two-body reactions [1]. It was issued as a compendium [2] and is available cost-free from the Nuclear Data Section of IAEA in Vienna, Austria. This package (originally containing just 11 neutron source reactions) is updated (and extended) frequently, its latest published version [3] is called DROSG-2000 (to be downloaded from http://www-nds.iaea.org/DROSG-2000.html). Presently 59 neutron source reactions are covered (see Table 1). Not included in this code are three (p,n) reactions which have a very narrow monoenergetic range only and which are mostly used for detector calibration in the keV range: 45Sc(p,n)45Ti [4,5], 51V(p,n)51Cr [4,5,6,] and 57Fe(p,n)57Co [4].

1.1. Differential neutron yields

The interactive and self-explaining program NEUYIE of the package DROSG-2000 calculates neutron energies, differential cross sections, and differential neutron yields. The main menu of the latest version of this program is shown in Table 1.

1.1.1 Cross-section database

There are three classes of cross section data as indicated in Table 1:

a) Complete angular distributions of differential cross sections (in some energy range).

b) Differential cross sections at 0 and/or 180.

c) Isotropic approximation from integrated cross sections.

Often the "isotropic approximation" of the differential cross sections was obtained from the corresponding time reversed (n,p0) or (n,d0) integrated cross sections as found in the evaluated neutron data files (e.g. ENDF/B-6) by detailed balance calculation. Especially in those cases, where (n,p) or (n,d) instead of (n,p0) or (n,d0) resp., had to be used, only a crude estimate is obtained. The accuracy of the differential cross section database differs from case to case. Usually, the source of the data is given at the end of each data file, sometimes also an estimate of the uncertainty. The error discussion for the standard sources (Table 1.1) as given in [2] is still more or less valid, even if the values of the cross section data have changed since then.

Table 1. From the main menu of the computer code. En0 range gives the limits of the mono-energetic energy range except for the multi-line (d,n) reactions (Table 1.3) where the maximum numbers of neutron lines at Ed=0 MeV is given. The alternate upper limit of the cross section range is just for the 0 cross section. All energies are given in MeV.

Table 1.1. Standard sources:

ID

REACTION TYPE

REMARKS

En0 RANGE

X-SECTION RANGE

1

3H(p,n)3He

gas target

0.064-7.585

1.0191-32.80/318.

101

 

T2O target

 

 

2

2H(d,n)3He

gas target

2.449-7.706

0.02 -39.80/85.

201

 

D2O target

 

 

202

 

d-octane target

 

 

3

1H(t,n)3He

gas target

0.574-17.64

3.051 - 98.19

301

 

water target

 

 

302

 

octane target

 

 

4

3H(d,n)4He

gas target

14.03-20.46

0.01 - 40.00/400.

401

 

T2O target

 

 

5

2H(t,n)4He

gas target

14.03-23.01

0.015-59.9/599.

501

 

D2O target

 

 

7

7Li(p,n0)7Be

 

0.030-0.650

1.8807-7.00/494.

701

 

7LiF target

 

 

702

 

7LiH target

 

 

8

1H(7Li,n0)7Be

 

1.441-3.842

13.097- 48.745

9

7Li(p,n1)7Be*

(0.429 MeV level)

0.038-1.557

2.40 - 7.00/20.

901

 

7LiF target

 

 

10

1H(7Li,n1)7Be*

(0.429 MeV level)

1.816-7.231

16.713- 48.745

Table 1.2. Less common (p,n)-sources

ID

REACTION TYPE

REMARKS

En0 RANGE

X-SECTION RANGE

11

6Li(p,n0)6Be

isotropic approx.

0.122-1.172

6.00 - 7.874/200.

12

9Be(p,n0)9B

 

-

2.20 -30.0

13

10Be(p,n0)10B

isotropic approx.

0.002-0.310

0.251 -1.040/20.247

14

1H(10Be,n0)10B

isotropic approx.

.2068-3.012

2.495 - 10.337/201.2

15

10B(p,n0)10C

isotropic approx.

0.041-4.055

4.94 - 8.571/17.1

16

11B(p,n0)11C

 

0.021-2.388

3.020/3.5 - 5.49/26.

17

1H(11B,n0)11C

 

2.538-11.88

33.-59.989/284.1

18

12C(p,n)12N

zero degree only

0.119-1.200

25.8

19

13C(p,n0)13N

 

0.017-2.278

3.239 - 12.86/30.6

20

1H(13C,n0)13N

 

2.792-12.18

41.803/112.28-165.97

21

14C(p,n0)14N

isotropic approx.

0.003-2.522

0.6714 - 3.151/20.67

22

1H(14C,n0)14N

isotropic approx.

0.586-9.782

9.332 - 43.795/287.2

23

15N(p,n0)15O

 

0.015-5.742

3.94 - 15.62

24

1H(15N,n0)15O

 

3.319-25.73

58.659 -232.549

25

36Cl(p,n)36Ar

isotropic approx.

.0001-2.028

0.878 - 2.103

26

1H(36Cl,n)36Ar

isotropic approx.

0.074-7.826

31.35 - 75.08

27

39Ar(p,n0)39K

isotropic approx.

.0002-2.593

1.225 - 1.300/20.224

28

1H(39Ar,n0)39K

isotropic approx.

0.214-10.28

47.367 - 50.28/782.1

29

59Co(p,n)59Ni

isotropic approx.

.0006-0.363

1.8897 - 2.240/11.89

30

1H(59Co,n)59Ni

isotropic approx.

1.830-4.198

110.534 - 131./695.5

59

18O(p,n)18F

isotropic approx.

0.008-1.199

2.58 - 20.

 

Table 1.3. Less common (d,n)-sources

ID

REACTION TYPE

REMARKS

En0 RANGE

X-SECTION RANGE

31

7Li(d,n)8Be

isotropic approx.

>=3 lv

0.01 - 10.957

32

2H(7Li,n)8Be

isotropic approx.

>=3 lv

0.035 - 38.5

33

9Be(d,n0)10B

isotropic approx.

>=5 lv

0.05 - 0.121/16.89

34

11B(d,n)12C

isotropic approx.

>=10 lv

0.411 - 2.513/5.564

35

2H(11B,n)12C

isotropic approx.

>=10 lv

2.247 - 13.82/30.6

36

13C(d,n)14N

isotropic approx.

>=5 lv

0.312 - 3.568

37

2H(13C,n)14N

isotropic approx.

>=5 lv

2.028 - 23.04

38

15N(d,n)16O

isotropic approx.

>=8 lv

2.13E-4 - 5.979/10.1

39

2H(15N,n)16O

isotropic approx.

>=8 lv

0.0016 - 44.53/75.2

40

18O(d,n)19F

isotropic approx.

>10 lv

0.975 - 2.204/14.696

41

20Ne(d,n)21Na

dummy data

0.197-0.344

1.E-5 - 0.140

42

2H(20Ne,n)21Na

dummy data

0.197-0.644

1.E-4 - 1.390

43

24Mg(d,n)25Al

dummy data

0.044-0.483

1.E-5 - 0.650

44

2H(24Mg,n)25Al

dummy data

0.044-1.192

1.2E-4 - 7.740

45

28Si(d,n)29P

dummy data

0.505-1.445

1.E-5 - 1.000

46

2H(28Si,n)29P

dummy data

0.505-3.208

1.4E-4 - 13.891

47

32S(d,n)33Cl

dummy data

0.049-0.855

1.E-5 - 0.900

48

2H(32S,n)33Cl

dummy data

0.049-2.207

1.6E-4 - 14.286

60

14N(d,n)15O

isotropic approx.

4.765-4.997

1. - 15.

Table 1.4. (alpha,n)-sources

ID

REACTION TYPE

REMARKS

En0 RANGE

X-SECTION RANGE

49

3H(4He,n)6Li

 

0.913-4.916

11.134-13.128/51.0

50

4He(3H,n)6Li

 

0.519-3.794

8.3906-9.893/38.4

51

7Li(4He,n)10B

isotropic approx.

0.146-1.528

4.3821-5.5106

52

4He(7Li,n)10B

isotropic approx.

0.449-2.429

7.6815-9.6596

53

11B(4He,n)14N

isotropic approx.

0.148-2.885

0.167-2.9396

54

4He(11B,n)14N

isotropic approx.

0.148-4.412

0.460-8.086

55

13C(4He,n)16O

isotropic approx.

2.084-7.024

0.0559-5.025

56

4He(13C,n)16O

isotropic approx.

2.084-10.54

0.1816-16.325

57

22Ne(4He,n)25Mg

isotropic approx.

0.004-0.700

0.5671 - 3.0

58

4He(22Ne,n)25Mg

isotropic approx.

0.103-1.504

3.1159 - 16.483

1.1.2 Kinematics calculations

The kinematics properties are calculated with the 1995 [7] (nuclear) masses using relativistic expressions. In most cases (not near thresholds) the mass uncertainty can be disregarded. It is assumed that the interacting nuclei are completely stripped which need not be true for a given situation.

1.1.3 Yield determination

For each energy and angle differential yields are calculated for such a target thickness that at 0 the neutron energy spread is 10 keV. The electronic stopping power calculation is usually based on data of Ziegler [8] unless shown otherwise at the end of each file. Using the values of Ziegler has proven to be the best in several cases.

For energies, which are moderately higher than the low energy maximum of the stopping power, the solutions of different authors differ by typically 5 to 10%. At very low energies the uncertainty in the energy loss can be comparatively large.

1.2 Thick target neutron yields

The energy width of "monoenergetic" sources for applied purposes will usually be wide. Therefore, the quantity of interest is the thick target yield of that source. The interactive and self-explaining program WHIYIE of the same package DROSG-2000 allows the calculation of thick target neutron spectra and yields at any angle and energy. The main menu is identical with that of NEUYIE (see Table 1).

1.2.1 Kinematic collimation

If in a two-body reaction the velocity of the center-of-mass (c.m.) is larger than the c.m. velocity of the particle that is emitted at 180 c.m., there will be two lines in the energy spectrum at 0: the primary line corresponding to 0 c.m. emission and the secondary, satellite line from 180 c.m. Such two-line neutron spectra occur in endothermic reactions either in a narrow energy range above the threshold or, if the projectile is heavier than the target nucleus and the target is protonium, over the entire energy range above the threshold. In such cases the neutron emission is compressed into a forward cone with two neutron groups at each angle inside the cone.

This confinement of the neutrons into a forward cone is very beneficial for the following reasons:

a) minimum room background

b) simplified shielding (it makes shadow bars at back angles obsolete)

c) strongly enhanced laboratory cross section of the 0 c.m. line

d) reduced laboratory cross section of the 180 c.m. satellite neutron line. Thus the satellite line may be disregarded in many applications. This is especially true at high enough projectile energies.

At a projectile energy Ep the (half) opening angle Q of the forward cone is given nonrelativistically by

sin2 Q = (1 - Eth/Ep) M2M4/M1M3

The masses Mi are those of the projectile, the target, the neutron and the residual nucleus resp., Eth is the threshold energy of the reaction.

For a given neutron energy En at 0 the following (nonrelativistic) relation holds

(1 + sin Q ) = (1+M2/M1)(1+M4/M3).En/Ep

Therefore, for a desired neutron energy the cone will become narrow with

a) M2 small,

b) M4 small and

c) Ep>>En, i.e. for reactions with large negative Q-values.

1.2.2 Thick target yields near threshold

For kinematically collimated neutron beams the opening angle becomes very small close to threshold, i.e. the beam is very narrow. This has two consequences:

a) The shape of a thick target yield curve in the double-valued energy region depends on the acceptance angle of the detector because the narrow beam does not necessarily illuminate the entire detector. This effect is shown in Fig. 1 for the case of 7Li(p,n0)7Be with acceptance angles of 2 and 5. (A differential yield curve - with 0 acceptance angle - will show infinities at the boundary angles of the neutron cone.)

b) The shape also depends on effects (angular straggling, elastic proton and neutron scattering) that change the outgoing neutron direction with regard to the incoming beam direction. So a narrow neutron beam can be deflected so much that it does not hit the detector at all. Therefore it is not surprising that the maximum of an actually measured 0 thick-target yield curve [9] is flatter and less pronounced than shown in Fig. 1.

 

 

 

 

 

Fig. 1. Thick-target yields of 7Li(p,n)7Be near threshold for a 2 opening angle (full curve) and a 5 opening angle (dashed).

 

Table 2 compares the total neutron output, the average neutron energy (at 0) and the differential neutron yield at 0 of various near-threshold-reactions.

Table 2. Energies and neutron yields in the double-valued energy region of near-threshold-reactions for fully stopped beams

 

0 values

total

Reaction

proj.

avg. n

neutron

n yield

Type

energy

energy

yield

into cone

 

[MeV]

[keV]

[n/sr.pC]

[n/pC]

3H(4He,n)6Li

14.326

2370.

538.6

673.4

4He(3H,n)6Li

9.6064

1403.

549.9

557.9

3H(p,n0)3He

1.1473

157.2

66.8

101.7

7Li(p,n0)7Be

1.9204

59.5

31.0

35.7

4He(7Li,n)10B

9.3300

1509

6.503

14.05

6Li(p,n0)6Be

6.0940

302.5

2.52

4.03

13C(p,n0)13N

3.2559

44.5

0.776

1.18

11B(p,n0)11C

3.0442

44.8

0.927

1.152

7Li(4He,n)10B

4.6494

396.

0.545

0.986

15N(p,n0)15O

3.7920

29.2

0.246

0.262

9Be(p,n0)9B

2.0840

50.0

0.036

0.037

10B(p,n0)10C

4.9274

97.0

0.0049

0.0076

14C(p,n0)14N

0.6749

54.6

2.8e-4

2.5e-4

59Co(p,n0)59Ni

1.8902

1.1

1.2e-6

1.5e-6

10Be(p,n0)10B

0.2522

3.7

2.4e-7

2.0e-7

22Ne(4He,n)25Mg

0.5713

7.

<5.e-11

 

1.2.3 Thick target yields of collimated neutron beams from inverse (p,n) reactions

Due to the fact that the proton mass is smaller than the neutron mass there is no upper threshold for the double-valued regime for inverse (p,n) reactions. Assuming a need of a cone with a 20 opening angle of all emitted neutrons, Table 3 gives relevant data to allow a comparison of such reactions under this condition.

Table 3. Properties of inverse (p,n) reactions, 20 degree opening angle of cone

 

0 degree values

total

 

high energy group

both groups

n yield

reaction

proj.

avg. n

neutron

avg. n

neutron

into

type

energy

Energy

yield

energy

yield

cone

 

[MeV]

[keV]

[n/sr.pC]

[keV]

[n/sr.pC]

[n/pC]

1H(7Li,n0)7Be

14.836

2051.

2208.

1772.

3283.

498.7

1H(t,n)3He

3.456

858.8

987.1

720.0

1474.

324.7

1H(11B,n0)11C

37.369

3977.

343.5

3279.

504.1

136.3

1H(13C,n0)13N

47.320

4165.

233.4

3334.

403.0

83.45

1H(15N,n0)15O

63.672

5245.

229.5

4359.

332.1

97.41

1H(59Co,n)59Ni

125.21

3151.

1.062

2613.

1.448

0.580

1H(14C,n0)14N

10.570

903.2

0.159

749.2

0.236

0.063

1H(39Ar,n0)39K

9.8475

262.5

0.7e-3

232.8

1.2e-3

1.0e-4

1H(10Be,n0)10B

2.8103

310.7

4.3e-5

258.6

6.5e-5

1.5e-5

2. More recent developments

2.1. Kinematically collimated neutron beams

2.1.1 1H(13C,n0)13N

This reaction gives kinematically collimated monoenergetic neutrons between 2.791 and 12.175 MeV. Beyond the latter energy neutrons from the n+p+12C exit channel will produce a break-up spectrum. Therefore it has the capability, like 1H(t,n)3He [2,10] and 1H(11B,n)11C [11] to produce neutrons in the "gap" region where no other monoenergetic sources are presently available.

Measurements at Tohoku University [12] have been reported with a 13C beam from a cyclotron at energies between 42.5 and 45.2 MeV producing neutrons between 3.6 and 5 MeV. After emptying the gas target the structural background was determined to be only a few % of the foreground. In addition, there were practically no gamma rays connected with the source.

More recently also at the Kyushu University this source has been tried using a 13C6+ beam of 59.3 MeV producing 7.2 MeV neutrons at 0 [13], somewhat closer to the "gap" region.

2.1.2 1H(7Li,n0)7Be

There has been a proposal from the Ukraine to build a lithium ion accelerator to take advantage of this source [14].

2.1.3 Windowless gas targets

Collimated neutron sources based on inverse (p,n) reactions and most of the other efficient neutron sources use an isotope of hydrogen as target medium. Disregarding cryogenic liquid targets the highest yield can be achieved with gas targets. The container of the target medium is usually a (thin walled) cell of stainless steel, with an entrance window towards the accelerator vacuum. At the other end there is a solid disc as a beam stop, which collects the charged particle beam.

A detailed description of target technology has been given before, e.g. [4] and [12]. Since then there has been a very important new development: practically massless gas containment by plasma port holes [15], which is beneficial at least in two ways: reduced structural background and reduced total power dissipation in the target. In addition, there is practically no energy degradation and straggling in the entrance window resulting in a sharper high-energy edge of the neutron distribution. This new technology appears to be by far superior to previous windowless target designs [16-18]. However, its rather high power consumption, cost and bulkiness restrict its general use.

2.2 Standard neutron sources

2.2.1 2H(d,n)3He

For obvious reasons this reaction is of particular interest in technical applications. There has been the development of portable sources based on this reaction, either using an accelerator [19] or fusion with electrostatic confinement [20].

There has been the intention by LLNL to build with a budget of about one million US$ an intense monoenergetic neutron source based on this reaction with a beam of 9 MeV deuterons of an intensity of 0.1 to 0.3 mA [21] to be used for the production of "pure" monoenergetic neutrons of about 12 MeV for neutron radiography. The best technology was going to be used, a windowless gas target (see 2.1.3) and a high-Z (Xe) gas beam stop to remove the target power. However, it was overlooked that at this energy the neutron yield from the deuteron break-up is much higher than the monoenergetic yield. Obviously, the 50-year old knowledge that there is a "gap" in the production of intrinsically pure monoenergetic neutrons between 8 and 14 MeV has not survived at LLNL.

Recently, also NIST, USA has shown interest in this source reaction, including the break-up spectra [22].

2.2.2 3H(d,n)4He

Interest was shown in the neutron spectra from deuteron break-up of this reaction [23].

2.2.3 7Li(p,n)7Be

A new nuclear data library has been reported for proton energies up to 150 MeV [24]

2.3 Isotope production for PET

To help with the prediction of neutron background when producing isotopes for positron emission tomography (PET) with small accelerators [25] the reactions with the IDs 59 and 60 (see Tables 1.2 and 1.3) were added to DROSG-2000.

3. Conclusion

The code DROSG-2000 allows prediction of most properties of 59 monoenergetic neutron sources (for a limited energy range). It is available free of charge. Thus there is little excuse for making basic mistakes when developing a neutron source for applied purposes.

Predicting thick target yield curves in the double-valued energy region near threshold is tricky because their shape is dependent on the acceptance angle of the detector and on microscopic angle changing effects (beam straggling, nuclear scattering).

In the "gap" region (8 to 14 MeV) 1H(t,n)3He surpasses its competitors 1H(11B,n0)11C and 1H(13B,n)13N in specific yield by more than an order of magnitude. However, the radioactivity of the t beam makes it worthwhile developing the latter sources.

Intense neutron sources below 14 MeV, e.g. for neutron radiography applications, have become of special interest, recently. It appears that too often much money is spent on projects that are, for plain physics reasons, not feasible.

REFERENCES

[1] M. Drosg, "Angular Dependencies of Neutron Energies and Cross Sections for 11 Monoenergetic Neutron Source Reactions", Computer-Code DROSG-87: Neutron Source Reactions (O. Schwerer, Ed.) Documentation series, Nuclear Data Section, October 1987.

[2] M. Drosg, O. Schwerer, "Production of Monoenergetic Neutrons between 0.1 and 23 MeV: Neutron Energies and Cross Sections", in Handbook on Nuclear Activation Data, K. Okamoto, Ed., IAEA Tech. Report Ser. 273, Vienna 1987.

[3] M. Drosg, " DROSG-2000v2.1: Neutron source reactions. Data files with computer codes for 57 accelerator-based two-body neutron source reactions", documented in the IAEA report IAEA-NDS-87 Rev. 7 (January 2002), IAEA, Vienna, see http://www-nds.iaea.org/DROSG-2000.html.

[4] C. A. Uttley, "Sources of monoenergetic neutrons", Neutron Sources for Basic Physics and Applications (S. CIERJACKS, Ed.), p.19, Pergamon Press, Oxford (1983).

[5] M. Drosg, "Properties of Monoenergetic Neutron Sources from Proton Reaction with Nuclei other than Tritons", p. 241, Proc. IAEA Consultants' Meeting on Neutron Source Properties, Debrecen 1980, K. Okamoto, Ed., IAEA/Int. Nucl. Data Comm. Report INDC(NDS)-114/GT (1980).

[6] M. Drosg, "Updating Survey of Some Less Common Fast Neutron Sources: 9Be(p,n)9B, 11B(p,n)11C, 51V(p,n)51Cr and 9Be(a ,n)12C" p. 285, Int. Atomic Energy Agency Report IAEA-TECDOC-410 (1987) (Proc. IAEA Adv. Group Meeting on Neutron Source Properties, Leningrad, June 1986).

[7] G. Audi and A.H. Wapstra, "The 1995 update to the atomic mass evaluation", Nuclear Physics A595, 409 (1995).

[8] J. F. Ziegler, ed., "The Stopping and Ranges of Ions in Matter", Vol.3 "HYDROGEN, Stopping Powers and Ranges in All Elements", Vol.5, "Heavy Ions, Stopping Powers and Ranges", Pergamon, 1977, 1980.

[9] W. I. Kononov, E. D. Poletaev and B. D. Jurlov, At. Energija 43, 303 (1977)

[10] M. Drosg, " Sources of Variable Energy Monoenergetic Neutrons for Fusion Related Applications", Nucl. Sci. Eng. 106, 279 (1990)

[11] S. Chiba, M. Mizumoto, K. Hasegawa, Y. Yamanouti, M. Sugimoto, Y. Watanabe, and M. Drosg, "The 1H(11B,n)11C Reaction as a Practical Low Background Monoenergetic Neutron Source in the 10 MeV Region", Nucl. Instr. Meth. Phys. Res. A281, 581 (1989)

[12] K. Hasegawa, K. Kotajima, M. Kitamura, T. Yamaya, O. Satoh, T. Ashinozuka, and M. Fujioka, "Production of Focused Neutron Beam Using Heavy Ion Reaction", p. 642 of Proc. 11th Int. Conf. on Cyclotrons and their Applications, Tokyo, 1987.

[13] Y. Watanabe, H. Nakamura, Y. Matsuoka, N. Ikeda, K. Sagara: "Development of Quasi-Monoenergetic Neutron Source Using the 1H(13C,n) Reaction", Eng.Sci.Rps., Kyushu University, 23, 285 (2001) and Y. Matsuoka, Y. Watanabe, S. Hachiya, H. Nakamura, Y. Tanaka, N. Ikeda, and K. Sagara: "Design and development of quasi-monoenergetic neutron source using the inverse kinematics of (p,n) reaction", Proc. Nuclear Data Symp. Nov. 18-19, 1999, JAERI, Tokai, Japan JAERI Conf-2000-005, 266 (2000)

[14] V.M. Sanin, V.A. Bomko, B.V. Zaitsev, and A.P. Kobets, "Ion linear accelerator as a source of narrow-beamed neutrons", Naprosy Atomnoj Nauki i Tekhniki,Yad.-Fiz. Issl. 3/34, 99 (1999)

[15] W. Gerber, R. C. Lanza, A. Hershcovitch, P. Stefan, C. Castle and E. Johnson, "The Plasma Porthole: a Windowless Vacuum-Pressure Interface With Various Accelerator Applications by Gerber", Proceeding of the 1998 Denton Conference, preprint as a priv. communication by R. C. Lanza, 1999 and AIP CP475, 932 (1999)

[16] H. W. Becker, L. Buchmann, J. Görres, K. U. Kettner, H. Kräwinkel, C. Rolfs, P. Schmalbrock, H. P. Trautvetter, and A. Vlieks, Nucl. Instrum. Meth., 198, 277(1982)

[17] D. D. Armstrong, C. R. Emigh, K. L. meier, E. A. Meyer, and J. D. Schneider, Nucl. Instr. Meth., 145, 127(1977)

[18] J. H. Deleeuw, A. A. Haasz, and P. C. Stangeby, Nucl. Instr. Meth., 145, 119(1977)

[19] J.W. Reichardt, MF Physics Corporation, Portable Pulsed Neutron Generator Specifications Private Communication (1999).

[20] J. Sved, "The First IEC Fusion Industrial Neutron Generator and Developments", p. 704, Proceedings of the Fifteenth International Conference on Applications of Accelerators in Research and Industry, Denton Texas, 1998.

[21] B. Rusnak, J. Hall, Proc. 16th Int. Conf. Application of accelerators in research and industry, Denton, Tx., 2000, AIP CP576, 1105(2001).

[22] Allan Carlson, NIST, USA, priv. communication (2002)

[23] C. Brune, Ohio Univ., USA, priv. communication (2001)

[24] S.G. Mashnik, M.B. Chadwick, H.G. Hughes, R.C. Little, R.E. MacFarlane, L.S. Waters, and P.G. Young, "7Li(p,n) nuclear data library for incident proton energies to 150 MeV", LANL (2002)

[25] L. Carroll and F. Ramsey, Berkeley, USA, priv. communication (2002)


© Manfred Drosg, Institut für Experimentalphysik der Universität Wien
Letzte Änderung am 12.09.2002 um 14:15 von MD