Neutron Scattering

More documents

Recommendations

Info

Schriften des Forschungszentrums Jülich Reihe Materie und Material / Matter and Materials Volume 15
Page 1: Forschungszentrum Jülich in der He
Page 5 and 6: Bibliographic information published
Page 8: Neutron Sources Harald Conrad
Page 11 and 12: number of neutron sources is descri
Page 13 and 14: ofthe reactor being a point source
Page 15 and 16: If we set aside the costs and ask a
Page 17 and 18: For uranium, which releases neutron
Page 19 and 20: neutron beann channels Fi 1 .5 Sche
Page 21 and 22: For these reasons a pulsed spallati
Page 23 and 24: (p,n)- and (d n)-Reactions Bombardi
Page 26: Properties of the Neutron Elementar
Page 29 and 30: In December 1942 Ferme build his fe
Page 31 and 32: For any practical application the i
Page 33 and 34: Table 2 .1 : Comparison of X-rays a
Page 35 and 36: this way even at a comparatively lo
Page 37 and 38: describes the solid angle dependent
Page 39 and 40: 9 We note one important exception,
Page 41 and 42: Therefore, for any scattering event
Page 43 and 44: Thereby we now also consider the sp
Page 45 and 46: 2 .7 Comparison between X-ray and n
Page 47 and 48: is also named magnetic form factor
Page 50: Elastic Scattering from Many-Body S
Page 53 and 54:
Fit. 3 .1 : A sketch of the scatter
Page 55 and 56:
A = 1Ps (r) - e'Q 'Yd3r (3 .6) Le.
Page 57 and 58:
k[Ä-1 ]z 0.695 E meV ,,[Ä] 9.0451
Page 59 and 60:
1 ik, r 2rnn fexp(iklr -i"'I) h 2 4
Page 61 and 62:
Under the assumption IRI » ~r 'I ,
Page 63 and 64:
translated pattern coincide for thi
Page 65 and 66:
more periods contribute to coherent
Page 67 and 68:
terni corresponds to thé scatterin
Page 69 and 70:
The most prominent example for nucl
Page 71 and 72:
Fil Schematic illustration of the i
Page 73 and 74:
Here, the magnetic moment ofthe neu
Page 75 and 76:
Fig. 3.10 : For magnetic neutron sc
Page 77 and 78:
Since the scattering amplitude is p
Page 79 and 80:
Here the magnetic form factor write
Page 82 and 83:
4 . Polarization analysis W . Schwe
Page 84 and 85:
40- E¢. 0. or P travel -03 E4- é0
Page 86 and 87:
1'10 tarns 1 MM ~2( Al WIRE (enamel
Page 88 and 89:
It follows that the nuclear scatter
Page 90 and 91:
Therefore the non-spin flip matrix
Page 92 and 93:
corrections for the ideal case can
Page 94 and 95:
ABA (deg ) Figure 4 .7 : Isotopic i
Page 96 and 97:
i Figure 4 .9 : Paramagnetic scatte
Page 98 and 99:
So far we have discussed the nuclea
Page 100 and 101:
With triple axis instruments one ca
Page 102 and 103:
The instrument DNS [15] (see Fig .
Page 104 and 105:
Current methods for complete polari
Page 106:
References [1] O . Halpern and M.R
Page 110 and 111:
5 . Correlation Functions Measured
Page 112 and 113:
S(Q) rnn =21r/r nn Figure 5 .1 : Sc
Page 114 and 115:
White" neutrons from reactor Sample
Page 116 and 117:
2 0 0 2 4 6 8 10 12 0 (A -1 ) Figur
Page 118 and 119:
where rit denotes the monomer dista
Page 120 and 121:
, TIIIIV~i~.~1111 a" Aj A(t) i ~M ~
Page 122 and 123:
(A(0)A(T» Figure 5 .9 : Simulated
Page 124 and 125:
where we can arbitrarily set ri = r
Page 126 and 127:
With this definition the pair corre
Page 128 and 129:
espectively. The former equation ex
Page 130 and 131:
to a volume V is simply a plane wav
Page 132 and 133:
is the Hamiltonian of a free atom a
Page 134:
Continuation Description : Grazing
Page 137 and 138:
A straightforward method to investi
Page 139 and 140:
To study the morphology of surfaces
Page 141 and 142:
6.3 Specular Neutron Reflectivity i
Page 143 and 144:
0 z>d d V(z) = 2nh2b,P, / mz =V, :
Page 145 and 146:
Figure 6 .7 : Sonie examples of mon
Page 147 and 148:
6.5 The Regime of the Total Externa
Page 149 and 150:
n, = 1- 8, + i(3, (6.19) The effect
Page 151 and 152:
too small to modulate the intensity
Page 153 and 154:
[9] V . Holt', U. Pietsch, T . Baum
Page 156 and 157:
7 . Diffractometer G . Heger 7 .1 I
Page 158 and 159:
scattered beam behind the sample, t
Page 160 and 161:
In the case of single crystal diffr
Page 162 and 163:
Powder diffraction also may be disc
Page 164 and 165:
For a ADP-powder diffractometer the
Page 166 and 167:
Ili1'i 11111111 i 0Y5 0.76 d spacï
Page 168:
The influence ofthe primary collima
Page 172 and 173:
8 . Small-angle Scattering and Refl
Page 174 and 175:
8 .3 .1 . Pin-Hole SANS The princip
Page 176 and 177:
determined by the maximum divergenc
Page 178 and 179:
the focusing SANS is known for long
Page 180 and 181:
three times, then one measures a Da
Page 182 and 183:
Figure 8 .12 : Schematic design ofa
Page 184 and 185:
Neutron guides also enable to trans
Page 186 and 187:
into two ionic particles with kinet
Page 188:
Crystal Spectrometer : Triple-axis
Page 191 and 192:
10 .1 Common features of crystal sp
Page 193 and 194:
undergo appreciable fluctuations .
Page 195 and 196:
Fig. 4) vertical focusing : The gai
Page 197 and 198:
Back to the "bottled" neutrons : in
Page 199 and 200:
Choosing PG or Cu one gets contribu
Page 201 and 202:
scan direction v scan direction dis
Page 203 and 204:
10.5 Back-Scattering Spectrometer I
Page 205 and 206:
After all ttrose constraints on the
Page 208:
10 Time-of-Flight Spectrometers Mic
Page 211 and 212:
ackscattering-z-spectrometer ; for
Page 213 and 214:
From the thermal spectrum of the ne
Page 215 and 216:
times is performed at the detector
Page 217 and 218:
energy transfers (gains) structures
Page 219 and 220:
is obtained, all constant factors a
Page 221 and 222:
Figure 10 .7 : Disc chopper . 10% t
Page 223 and 224:
etween the two choppers . See also
Page 225 and 226:
10 .2 .8 TOF-TOF : TOF-monochromato
Page 227 and 228:
the associated paths are indicated
Page 229 and 230:
10 .3 .1 Analysis by filters The an
Page 231 and 232:
if an increase in resolution may be
Page 234:
Neutron Spich-echo Spectrometer, NS
Page 237 and 238:
affecting application are caused by
Page 239 and 240:
through one arm of the spectrometer
Page 241 and 242:
direction that gives rise to a new
Page 243 and 244:
11 .3 The detector signal As mentio
Page 245 and 246:
proportional to the current through
Page 247 and 248:
I (Q, t) and the exact symmetry poi
Page 249 and 250:
then additional deactivation of the
Page 251 and 252:
ô 0 .8 0 0 Im 0 .6 X ,a, `RMRXI km
Page 253 and 254:
Many isotopes-especially normal hyd
Page 256:
12 Structure Determination Gernot H
Page 259 and 260:
Besides of the related seven primit
Page 261 and 262:
fM(H) = Jv Mj(r)-exp[2ni(H-r)]- &r
Page 263 and 264:
12 .3 .1 Example ofcontrast variati
Page 265 and 266:
Fig . 2 . Magnetic phase diagram of
Page 267 and 268:
Fig . 3 . Na2S-9D20 : A partial vie
Page 269 and 270:
Remember: The scattering lengths of
Page 271 and 272:
(3m symmetiy) on crystallographic s
Page 273 and 274:
Textbooks G . E. Bacon, Neutron Dif
Page 276 and 277:
13 . Inelastic neutron scattering :
Page 278 and 279:
(000) Figure 2 Schematic drawing of
Page 280 and 281:
o o o o bo ao Lambda lattice parame
Page 282 and 283:
Tau Figure 5 Scattering triangle co
Page 284 and 285:
e performed in an efficient manner
Page 286 and 287:
1 r x z -- w --Z x E r A -+ L 6 5 _
Page 288 and 289:
1s. - 1 tUMl [cc01 ~ 1 ~ 10 517 if
Page 290 and 291:
Similar branches may induce larger
Page 292 and 293:
Figure 10 Schematic picture of a di
Page 294 and 295:
T>Tc TTc O O O O " O " O 8 8 " " 2
Page 296 and 297:
14 a15spin-wave Magnon- energy the
Page 298 and 299:
Ferromagnetic materials are still o
Page 300 and 301:
; ' . r,°'r, Figure 17 Crystal fie
Page 302:
14 Soft Matter : Structure Dietmar
Page 305 and 306:
with the macroscopic scattering cro
Page 307 and 308:
The probability that a freely joint
Page 309 and 310:
2.5 2.0 0.0 0.5 1 .0 1 .5 2.0 2.5 3
Page 311 and 312:
Equations (14 .12) and (14 .13) are
Page 313 and 314:
`l ~(Q)- ,"o (D(1-d)VP(Q) dn NA - ~
Page 315 and 316:
with c the volume fraction of polym
Page 317 and 318:
3 .0 ô 2 .5 U 2 .0 O 1 .5 a 1 .0 0
Page 319 and 320:
6 Û ô 4 3 .0 2 .5 ; 0 1 .5 0 .0 0
Page 321 and 322:
[11] D . Schwahn, K . Mortensen, T.
Page 324 and 325:
15 . Polymer Dynamics D. Richter 15
Page 326 and 327:
is the Kohlrausch-William-Watts rel
Page 328 and 329:
Figure 15 .2 : Elastic and inelasti
Page 330 and 331:
S (Q, t) = Sa (Q, t) S ß (Q, t) /
Page 332 and 333:
Fig .15 .6 displays the elastic int
Page 334 and 335:
C 0.8 d 0.6 ô, 0.4 0.2 o I-Ll1 I I
Page 336 and 337:
15.3 .1 Entropie forces - the Rouse
Page 338 and 339:
By means of neutron scattering two
Page 340 and 341:
The pair correlation function arisi
Page 342 and 343:
The dashed line gives the Rouse pre
Page 344 and 345:
Having obtained very good agreement
Page 346 and 347:
2 diameter d . At that time (ze) th
Page 348 and 349:
Figure 15.17 : Dynamic structure fa
Page 350 and 351:
Finally, one may test whether only
Page 352:
C Theoretieal Work [14] G . Ronca,
Page 356 and 357:
16 Magnetisin Thomas Bi ückel, IFF
Page 358 and 359:
ole, compared to the stronger excha
Page 360 and 361:
16.2 Magnetic Structure Determinati
Page 362 and 363:
The scattering power density can bc
Page 364 and 365:
the magnetisation density of one at
Page 366 and 367:
y r f R(Q)- (du /dS2) ++ - u a b z1
Page 368 and 369:
fluctuate in space and time . A pha
Page 370 and 371:
same and do not depend on the detai
Page 372 and 373:
Figures 16 .10 and 16.11 show the m
Page 374:
temperature superconductors, or exc
Page 378 and 379:
Chapter 17 Translation and Rotation
Page 380 and 381:
(T2 is related to the mean square d
Page 382 and 383:
Figure 17 .1 : Mean square displace
Page 384 and 385:
site with possible neighbour sites
Page 386 and 387:
decreased barrier increases the pro
Page 388 and 389:
17 .3 Rotation Molecules represent
Page 390 and 391:
,~ 1 = 0 represents the totally sym
Page 392 and 393:
The Id rotor : solution based on 'f
Page 394 and 395:
The Id rotor : pocket state formali
Page 396 and 397:
Each new model of coupled motion re
Page 398:
18 Texture in Materials and Earth S
Page 401 and 402:
In this contribution, however, we w
Page 403 and 404:
material . Texture is an important
Page 405 and 406:
. . It is convenient to plot these
Page 407 and 408:
Fig . 18 .12 : Examples of crystall
Page 409 and 410:
pole figures require numbers of 104
Page 411 and 412:
5 .1 Pole Figure Inversion The dét
Page 413 and 414:
lization (generation of dislocation
Page 415 and 416:
1990 1994 1996 Fig. 18.23 : Experim
Page 417 and 418:
Quartz HK407 ô m 6 Fig . 20 . . .
Page 419 and 420:
(3) Preferred orientations of the f
Page 421:
Schriften des Forschungszentrums J
show all

Neutron Scattering

Create successful ePaper yourself

Delete template?

Save as template?