Upgrades of poloidal and tangential x-ray imaging crystal spectrometers for temperature and rotation measurements on EAST

Fudi Wang; Jun Chen; Ruiji Hu; Bo Lyu; Gilles Colledani; Jia Fu; Yingying Li; Manfred Bitter; Kenneth Hill; Sangon Lee; Minyou Ye; Yuejiang Shi; Baonian Wan

doi:10.1063/1.4963150

Upgrades of poloidal and tangential x-ray imaging crystal spectrometers for temperature and rotation measurements on EAST

Rev Sci Instrum. 2016 Nov;87(11):11E342. doi: 10.1063/1.4963150.

Authors

Fudi Wang¹, Jun Chen¹, Ruiji Hu¹, Bo Lyu¹, Gilles Colledani², Jia Fu¹, Yingying Li¹, Manfred Bitter³, Kenneth Hill³, Sangon Lee⁴, Minyou Ye⁵, Yuejiang Shi⁵, Baonian Wan¹

Affiliations

¹ Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China.
² CEA, IRFM, F-13108 St Paul-lez-Durance, France.
³ Princeton Plasma Physics Laboratory, MS37-B332, Princeton, New Jersey 08543-0451, USA.
⁴ National Fusion Research Institute, 52 Eoeun-Dong, Yusung-Gu, Daejeon 305-333, South Korea.
⁵ School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230026, China.

PMID: 27910459
DOI: 10.1063/1.4963150

Abstract

During the past two years, key parts of poloidal and tangential x-ray imaging crystal spectrometers (PXCSs and TXCSs) have been upgraded. For poloidal XCSs, double-crystals of ArXVII and FeXXV were deployed. For fulfilling in situ alignment of a poloidal XCS, the beryllium window must be flexibly removed. By utilizing a design, where the beryllium window was installed in the vacuum chamber of the double-crystal, and between the double-crystal and wall of this chamber, an in situ alignment for the two spectrometers was fulfilled. Also, a new holder for the double-crystal was installed to allow for precise adjustments of azimuth angle and vertical height of the double-crystal. In order to facilitate these adjustments of double-crystal and installation of beryllium window, the chamber of the double-crystal for PXCS was upgraded from a cylinder to a cuboid. The distance between double-crystal and magnetic axis was extended from 8936 mm to 9850 mm in order to improve spatial resolution for PXCS, which is currently in the range from 1.237 mm to 4.80 mm at magnetic axis. Furthermore, a new pixelated detector (PILATUS 900K), which has a large sensitive area of 83.8 × 325.3 mm² and which is vacuum compatible, is being implemented on the PXCS. This detector is mounted on a rail, so that its position can be changed by 50 mm to effectively record spectra of He-like argon and He-like iron (ArXVII and FeXXV). Similarly, a rail, which allows detector movement by 50 mm, was also installed in TXCS to alternatively record spectra of ArXVII and ArXVIII. Presently, the operation duration of PXCS and TXCS has been upgraded to hundreds of seconds in one shot. T_i- and u_ϕ-profiles measured by TXCS and charge exchange recombination spectroscopy (CXRS) were compared and found to be in good agreement.