OPERATION TESTS of the 260 MHz 1500 W SOLID STATE RF AMPLIFIER at TARLA FACILITY

Year 2019, , 181 - 196, 01.12.2019

Özlem Karslı Evrim Colak

https://doi.org/10.33769/aupse.557951

Abstract

Turkish Accelerator and Radiation Laboratory
(TARLA) will be the first accelerator-based user facility in Turkey. The
facility is under construction at the Institute of Accelerator Technologies of
Ankara University. Based on the state-of-art superconducting technology, TARLA
accelerator offers a multi-experimental facility providing a variety of
accelerator-based radiation sources for users coming from various fields like
chemistry, physics, biology, material sciences, medicine and nanotechnology. TARLA
consists of two acceleration lines: the first one is the injector that provides
high current continuous wave (CW) electron beam at 250 keV energy, and the
second one is the main accelerator that comprises of two superconducting (SC) cryomodules
separated by a bunch compressor in order to accelerate the electron beam up to
40 MeV energy. Two normal conducting accelerators, so called subharmonic (SHB)
and fundamental (FB) buncher cavities whose operation frequencies are 260 and
1300 MHz, respectively, are used to compress the electron bunches from ~600 ps
to ~10 ps. SHB cavity is powered by a 1500 W Radio-frequency (RF) power
amplifier. Currently, the electron gun training, and superconducting modules
acceptance tests, personal safety system, and helium cryogenic system
commissioning tests are performed simultaneously. In this study, we present the
operation tests of the 1500 W RF amplifier in the scope of the commissioning
tests of injector line which showed phase drift coefficents of ~0.5 deg/C^o
and ~0.67 deg/C^o in repeated tests. Moreover, the importance of
constancy of the water pressure in the water-cooling line for phase constancy
of the delivered power has become evident as a result of current obervations.

Keywords

Radiofrequency (RF), solid state amplifier, accelerator, bunch length, phase stability, high power, operation test

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