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Ionisation chambers (IC) are commonly used in
hard X-ray beam lines to measure intensity of X-ray beam. ICs are gas (in this
case argon) filled detectors, which can be used for various purposes in a
beamline. They are kept just before the experimental station to monitor the
incident intensity (I0) of x-ray beam. They can also be kept
immediately after a double crystal monochromater (DCM) to align for DCM crystals
and used in detuning the second crystal to suppress higher order harmonics. A
large area IC has been designed fabricated and tested on 3kW, CuKa
x-ray source.
Removable FS along
with a CCD camera is used at several places in a beamline for visual feedback of
X-ray beam. Vacuum compatible material Red cd 106™ has been deposited on a flat
glass substrate. The fluorescence has been checked on a 3 kW X-ray generator and
the signal has been picked up on a CCD camera. The stepper motor surface driver
interface has been developed for removing the FS from the beam path, once
optical alignment of the beam is over.
Apertures are used
to define the photon beam and the acceptance of the beamline, precisely.
Uncontrolled beam can damage the optical element, because of high heat load. The
blades of aperature define the beam in horizontal and vertical planes.Such an
aperture with four blades system, two horizontal and two vertical, which makes
maximum aperture size 80mmx30mm has been developed.
- Synchrotron Optics cleaning system
Synchrotron optical
elements are operated in high / ultra high vacuum environment. Even in this
environment, carbon contamination is practically unavoidable in the presence of
intense x-ray synchrotron beam. Carbon contamination decreases the efficiency
of the optical elements (mirrors, gratings etc.). Various methods are used to
clean the contaminated optics Cleaning of carbon contamination by oxygen plasma
produced by RF source gives the most efficient cleaning. An RF plasma cleaning
system has been developed and has been tested to clean a glass substrates
coated by carbon soot as well as by vacuum evaporation of carbon. The carbon
contamination can be removed without any appreciable degradation of the
reflectivity.
- Development of D.C. Sputtering system
Figure 16 : D.C.Sputtering
Setup Figure 17 : Sputter coated cavity
A d. c.
sputtering system is developed for deposition of thin film of titanium inside
ceramic cavities (105x50x400mm) of Indus-2 kicker magnet. Number of glass plates
are coated with this system to optimize the parameters. Thickness measurement
is done by a surface profiler. Average thickness of 2 micron is observed. The
adhesion of film is very good. Any type of tube, cavity or chamber can be coated
from inside with any conducting film by this system. Other metallic films like
niobium, chromium and nickel are also coated by this system.
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