Comparison of Nano/Micro Lead, Bismuth and Tungsten on the Gamma Shielding Properties of the Flexible Composites against Photon in Wide Energy Range (40 keV to 662 keV)

A new ultrahigh-energy-resolution and wide-energy-range soft X-ray beamline has been designed and is under construction at the Shanghai Synchrotron Radiation Facility. The beamline has two branches: one dedicated to angle-resolved photoemission spectroscopy (ARPES) and the other to photoelectron emission microscopy (PEEM). The two branches share the same plane-grating monochromator, which is equipped with four variable-line-spacing gratings and covers the 20–2000 eV energy range. Two elliptically polarized undulators are employed to provide photons with variable polarization, linear in every inclination and circular. The expected energy resolution is approximately 10 meV at 1000 eV with a flux of more than 3 × 1010 photons s−1at the ARPES sample positions. The refocusing of both branches is based on Kirkpatrick–Baez pairs. The expected spot sizes when using a 10 µm exit slit are 15 µm × 5 µm (horizontal × vertical FWHM) at the ARPES station and 10 µm × 5 µm (horizontal × vertical FWHM) at the PEEM station. The use of plane optical elements upstream of the exit slit, a variable-line-spacing grating and a pre-mirror in the monochromator that allows the influence of the thermal deformation to be eliminated are essential for achieving the ultrahigh-energy resolution.

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XAFS and X-MCD spectroscopies with undulator gap scan

Journal of Synchrotron Radiation ◽

10.1107/s0909049597014702 ◽

1998 ◽

Vol 5 (3) ◽

pp. 989-991 ◽

Cited By ~ 16

Author(s):

Andrei Rogalev ◽

Vincent Gotte ◽

Jose´ Goulon ◽

Christophe Gauthier ◽

Joel Chavanne ◽

...

Keyword(s):

Energy Range ◽

Absorption Spectroscopy ◽

Emission Peak ◽

Photon Statistics ◽

Wide Energy Range ◽

X Ray ◽

Polarization Rate ◽

Spin Polarized ◽

Wide Energy ◽

X Ray Absorption

The first experimental applications of the undulator gap-scan technique in X-ray absorption spectroscopy are reported. The key advantage of this method is that during EXAFS scans the undulator is permanently tuned to the maximum of its emission peak in order to maximize the photon statistics. In X-MCD or spin-polarized EXAFS studies with a helical undulator of the Helios type, the polarization rate can also be kept almost constant over a wide energy range.

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Энерговыделение при бомбардировке атомами дейтерия поверхности вольфрама

Письма в журнал технической физики ◽

10.21883/pjtf.2019.11.47827.17771 ◽

2019 ◽

Vol 45 (11) ◽

pp. 51

Author(s):

Д.С. Мелузова ◽

П.Ю. Бабенко ◽

М.И. Миронов ◽

В.С. Михайлов ◽

А.П. Шергин ◽

...

Keyword(s):

Energy Loss ◽

Energy Range ◽

Energy Release ◽

Maximum Energy ◽

Wide Energy Range ◽

Tokamak Reactor ◽

Tungsten Target ◽

Wide Energy ◽

Bragg Maximum ◽

Maximum Energy Release

The distribution of energy release (linear energy loss) over depth was calculated when bombarded with deuterium atoms of a tungsten target in a wide energy range of incident particles of 100 eV - 10 MeV. It is shown that in the energy range up to 100 keV, the maximum energy release, contrary to the prevailing ideas, is near the surface of a solid. At energies above 100 keV, the nature of the distribution changes and the Bragg maximum appears near the point where the particle stops. The distribution of the energy release over depth in tungsten is obtained for conditions typical of the ITER tokamak reactor, which makes it possible to estimate the wall heating during bombardment by plasma atoms.

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