|
Element |
Total Neutron Cross Section (1) |
Coherent Scattering Length (1) |
Critical Velocity m/s |
Magnetic Susceptibility X10^-6 cgs |
|
Carbon |
4.75 b |
6.657 fm |
Dia. 7.65, Gra. 6.11 (2) |
Dia. -5.9, Gra. -6.0 (6) |
|
CVD (dueterated NIM) |
V=220 neV (4) |
6.49 |
||
|
PLD (exp) |
Nb 9.4 9.7 10^14 (5) |
6.95 |
||
|
CVD (exp NIM) |
N b 5.29 10^14 (4) |
5.13 |
||
|
CVD (exp) |
Nb 4.4 10^14 (5) |
4.68 |
||
|
Nitrogen |
12.5 b |
9.38 fm |
N2 -18.9 (6) |
|
|
Hydrogen |
20.436 b free |
-3.739 fm |
H2 -3.98 (6) |
|
|
Hydrogen [J0] |
20.436 b free |
-23.719 fm |
||
|
Hydrogen [J1] |
20.436 b free |
5.414 fm |
||
|
Deuterium |
3.390 b free |
6.672 fm |
||
|
Deuterium [J3/2] |
3.390 b free |
6.35 fm |
||
|
Deuterium [J1/2] |
3.390 b free |
.65 fm |
||
|
Copper |
11.7 b |
7.63 fm |
5.66 (2) |
-5.6 (6) |
|
Copper 65 |
17.7 b |
11.09 fm |
6.76 (2) |
-5.6 (6) |
|
Beryllium |
6.149 b |
7.74 fm |
6.89 (2) |
-9.0 (6) |
|
BeO |
6.99 (2) |
-11.9 (6) |
||
|
Ni 58 |
30.4 b |
14.4 fm |
8.14 (2) |
ferro |
|
C3N4 (theoretical) |
? 9.17 b |
8.21 fm |
Dia. 8.47 Gra. 6.79 (3) |
|
|
C2N |
7.56 fm |
7.5 (7) |
||
|
BeO |
6.99 2 |
-11.9 (6) |
1 - From Neutron Cross sections, S. F. Mughabghab and D. I. Garber, June 1973
2 - From The Physics of Ultracold Neutrons, V. K. Igantovich 1990
3 – Using diamond and graphite atomic densitys as approximations.
4 - M.G.D. van der Grinten et al, "Characterization and development of Diamond-like Coatings for Storing Neutrons", Nucl. Inst. and Meth. A, Vol. 423, 1999, pp. 421-427
5 - Findeisen, E. et al, "Hydrogen concentration and mass density of diamond-like carbon films obtained by X-ray and neutron diffraction", Journal of Applied Physics, vol. 76, no. 8, 15 Oct. 1994, pp. 4636-42
6 - CRC Handbook of Chemistery and Physics
7 - Density of Sandia carbon coating used in this calculation
|
Probability of spin flip per collision (10-6) |
Probability of losses per collision (10-5) |
|
|
1. Be (trap) |
7.2±0.7 |
|
|
2. Be (trap+foils) |
7.7±0.7 |
7.1±1.1 |
|
3. SiO (guartz) |
14±1 |
59.8±6.0 |
|
4. BeO (before outgassing) |
48±5 |
168±15 |
|
5. BeO (after outgassing) |
44±4 |
74±7 |
|
6. Glass: SIO2 81% B2O2 13% Na2O+K2O 4% Al2O3 2% |
95±9 |
315±30 |
|
7. C (graphite) |
1.9± 1.0 |
18.6±2,0 |
|
8. Brass (63% Cu, 37% Zu) |
1.1± 1.0 |
19.3±2.0 |
|
9. Cu |
-1.2± 1.0 |
20.0±2.0 |
|
10. Teflon (CF4) |
1.8± 1.0 |
23.5±2.0 |
Table A7.2. The spin-flip probability and loss probability per surface collision for various materials.