Nuclear Instruments and Methods in Physics Research A 467–468 (2001) 51–54 Present status of the Siam Photon Laboratory Weerapong Pairsuwan a , Prayoon Songsiriritthigul a , Masumi Sugawara a , Goro Isoyama a,b , Takehiko Ishii a, * a National Synchrotron Research Center, SUT, 111 University Avenue, P.O. Box 93, Nakhon Ratchasima Suranaree 30000, Thailand b Institute of Industrial Science, Osaka University, 8-1 Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan Abstract The Siam Photon Project promoted at the Siam Photon Laboratory is progressing slowly but steadily. The construction of the laboratory building was completed and the installation of the accelerator complex, that is the modified SORTEC machines from Tsukuba, is now under way. The first stage of the synchrotron assembly has been completed recently. The installation of the injector linac is about to be started. The construction of the additional magnet system, the new machine control system and the new vacuum chambers have been completed. The construction of the first beam line with photoemission experimental stations as well as that for the electron beam monitor will start soon. The design work for an undulator will also start soon. Some problems found in the case of the utilization of a second hand system are described. # 2001 Elsevier Science B.V. All rights reserved. PACS: 07.85.Qe; 29.20.Oh Keywords: Synchrotron radiation facility; Siam photon project NSRC 1. Introduction The National Synchrotron Research Center (NSRC) was established in May 1996, by the Ministry of Science, Technology and Environment of Thailand for promoting the Siam Photon Project, the national synchrotron radiation re- search project of Thailand. The Siam Photon Laboratory belongs to NSRC. Some details of the Siam Photon Laboratory were reported in the SRI’97 Conference held in Himeji [1]. The essence of the Siam Photon Project is summarized as follows: (1) An accelerator complex consisting of a 40 MeV injector linac, a 1.0 GeV booster synchro- tron and a 1.0 GeV storage ring for a light source is constructed. (2) Beam lines and experimental stations associated with the light source are built. More detailed descriptions of the project have been presented elsewhere [2,3]. SORTEC Laboratory in Tsukuba originally owned the accelerator complex. Whole accelera- tors were dismantled and the components were sent to the Siam Photon Laboratory in December 1996. Since the SORTEC Storage Ring transferred to the Siam Photon Laboratory was optimized to the microlithography studies and not suitable for other contemporary scientific research, NSRC decided to reform the storage ring so that the natural emittance of the electron beam is reduced and long straight sections for insertion devices are *Corresponding author. Tel.: +66-44-22-4763; fax: +66-44- 21-6311. E-mail address: ishii@nsrc.sut.ac.th (T. Ishii). 0168-9002/01/$-see front matter # 2001 Elsevier Science B.V. All rights reserved. PII:S0168-9002(01)00220-0