Neutron Scattering

C
0.8
d 0.6
ô,
0.4
0.2
o I-Ll1 I I I . Y
10-4 10-3 10_ 2 10-1 101 lo 1
t/T
ô
0 .8
C~ 0 .4
0
0 .2
0
d 1 d I e l d LULll J i 2
10-12 10 -10 10-8 10-6 10-4 10-2 10o
t/T
11
Figure 15 .8 : NSE spectra from PB taken at the first and second structure factor peak. The
time is rescaled with the temperature dependence from flow relaxation . Center :
S(Q) for different temperatures .
Fig .15 .9 displays the temperature dependence ofthe corresponding relaxation rates .
While the
data at the first peak nicely agree with the temperature dependence of the a-relaxation, as
already evidenced by the scaling, the relaxation rates taken at the second peak follow an