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Along this line one does not observe any acceleration. Here one observes the full acceleration, but delayed in time by R/c !. Radiation from a dipole-antenna. Guess that. 2. To get the dimension right !. Electromagnetic radiation. due to the oscillating charge in the antenna.
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Along this line one does not observe any acceleration Here one observes the full acceleration, but delayed in time by R/c ! Radiation from a dipole-antenna Guess that 2 To get the dimension right ! Electromagnetic radiation due to the oscillating charge in the antenna
Polarisation P=cos2(ψ) P=1
k’ Q Phase 0 . p 2 . p 4 . p wavecrest k many z l Number density Interference (mathematical) 1,2 … many 2 r 1 as drawn #2 is behind #1 for ”in” but ahead for ”out” , therefore ” – ”
Measuring atomic and molecular formfactors from gas scattering Detector Viewing Field Detector 2q Kr X-ray beam Gas cell
a=[15.2354 6.70060 4.35910 2.96230]; b=[3.0669 0.241200 10.7805 61.4135]; c=1.71890; % Ga a=[16.6723 6.0710 3.4313 4.27790]; b=[2.63450 0.2647 12.9479 47.7972]; c=2.531; % As
Q q dq r r f df Unit sphere
Convolution of 2 Gaussians i.e. h(x) is also Gaussian with
locally a plane wave Energy density Surface area Side View Ring wave (2D) or Spherical wave (3D) Top View
scattering length Spherical wave k’ Area is k Perfect plane wave Almost plane wave when Aperture d Defines the scattering cross section A point scatterer in the beam
P(l) l l-Dl Dl wavelength band l From the 2 equations, derive No real beam is perfectly monochromatic 2LL=Nl 2LL=(N+1)(l-Dl) the longitudinal coherence length
P(q) source observation point With R being the distance from to Dq show from the figure that q Dq A and B out-of-phase A Dq D LT B Here Aand B beams in phase No real beam is perfectly collimated The transverse coherence length
The experimental setup CCD 0.7 x 0.7 mm Sample Scintillator Dq< 2 mdeg X-rays E = 8-27 keV 20mm Rotation
Tomography • Study the bulk structures, 3D • Nondestructive • Small lengthscales (350 nm) Single slice 100 microns Galathea III Fra http://www.unge-forskere.dk/
Compton Scattering Energy and momentum conservation