111161553
Vacuum monitoring system of HLS storage ring
The vacuum monitoring system of Hefei Light Source (HLS) storage ring is a subsystem of the upgraded HLS control system, which is based upon EPICS. There are 6 Varian vacuum Multi-Gauges controllers around the storage ring of HLS to monitor the pressure of 15 positions. An Industrial PC is used as Input/Output Controller (IOC) and it connects the 6 Varian vacuum Multi-Gauge controllers with serial communication (RS485 mode). The pressure values are displayed in a PC with Linux, which is used as operator interface (OPI). The pressure values are archived in a database and some data analyses are also done.
32668015
A Method to Calibrate Beam Position Monitor at HLS 200 MeV Linac
In order to improve injection efficiency of HLS 200Mev LINAC, we redesign a new strip line beam position monitor system, which is consisted of a strip line structure and a signal processing system. We decide on an online calibration method based on beam to find out the geometry centre displacement and relative gain offset. Before the BPM testing bench has been prepared, we make a simulation based on the model accounted for all factors influencing signal amplitudes and get the calibrating results. At last, we analyze the nonlinearity effect on the calibration results.
55509875
A LOW COST AND HIGH EFFICIENCT FACILITY FOR REMOVAL OF SO2 AND NOx IN THE FLUE GAS FROM COAL FIRE POWER PLANT
The emission of toxic gas, sulfur oxides and nitrogen oxides has become serious issue in the world. A review of EB method to remove the SOx and NOx in flue gas from coal-fired power plants was described in this paper. A design of an electron curtain accelerator of 600 keV was given, and a facility for purification of flue gas from coal combustion power plant of 10MW was described here.
55223511
Upgrade of NSRL optical klystron for FEL
A symmetric optical klystron (OK) will be upgraded to an asymmetric structure for generating a more powerful coherent harmonic FEL after measuring the buncher parameters from the OK spontaneous emission spectrum. The period of an independently adjusted modulator will be extended from 7.2cm to 9.2cm for a higher operation energy that will facilitate the progress of coherent harmonic generation FEL experiments. The upgraded OK parameters are listed and checked by the 3-dimensional electromagnetic computation code. Special considerations are given for possible upgrade schemes.
56215933
PLC and Linux based control system for the CAMD Linac
Louisiana State University Center for Advanced Microstructures and Devices (CAMD) began operations in the fall of 1992. At the time, the facility had separate control systems for the storage ring and Linac. In 1997, CAMD began a control system upgrade project with the goal of producing a single unified control system running on the PC/Linux platform. After completion of the storage ring control system, the Linac control system was designed utilizing AutomationDirect.com PLCs for the real-time components, and PC/Linux for the user interface. The new Linac control system has been completed, and has been operational since July 2002. This paper will discuss the objectives, design, and future upgrade plans for the Linac control system, as well as the experiences with replacing the CGR-MeV VME/OS/9 control system with a PLC/PC/Linux based system.
121568193
Energy determination at BEPC-II
The BEPC-II collider beam energy calibration system is discussed. The system is based on the Compton backscattering method. The expected precision of the electron and positron beam energy e determination is δ e / e ≈ 3 ⋅ 10 − 5 .
118625117
Different Evolutionary Stages in the Massive Star-forming Region W3 Main Complex
Aims. Massive stars form in clusters, and they are often found in different evolutionary stages located close to each other. To understand evolutionary and environmental effects during the formation of high-mass stars, we observed three regions of massive star formation at different evolutionary stages that reside in the same natal molecular cloud. Methods. The three regions S255IR, S255N and S255S were observed at 1.3 mm with the Submillimeter Array (SMA) and followup short spacing information was obtained with the IRAM 30m telescope. Near infrared (NIR) H + K-band spectra and continuum observations were taken for S255IR with VLT-SINFONI to study the different stellar populations in this region. Results. The combination of millimeter (mm) and near infrared data allow us to characterize different stellar populations within the young forming cluster in detail. While we find multiple mm con tinuum sources toward all regions, their outflow, disk and ch emical properties vary considerably. The most evolved source S255IR exhibits a collimated bipolar outflow visible in CO and H 2 emission, the outflows from the youngest region S255S are still small an d rather confined in the regions of the mm continuum peaks. Als o the chemistry toward S255IR is most evolved exhibiting strong emission from complex molecules, while much fewer molecular lines are detected in S255N, and in S255S we detect only CO isotopologues and SO lines. Also, rotational structures are found toward S255N and S255IR. Furthermore, a comparison of the NIR SINFONI and mm data from S255IR clearly reveal two different (proto) stellar populations with an estimated age difference of approximately 1 Myr. Conclusions. A multi-wavelength spectroscopy and mapping study reveals different evolutionary phases of the star formation regions. We propose the triggered outside-in collapse star formation scenario for the bigger picture and the fragmentation scenario for S255IR.
61057086
The BEPC control system upgraded
The upgrade of the BEPC control system has been finished one year ahead of the schedule and new system was put into use in October, 1994. The upgraded system adopts a distribution architecture based on DECnet. The workstations are used as console to replace the old hardware console, the new VAX computers carry out control jobs. Some dedicated adapters have been eliminated. Up to now, the new BEPC control system has been running safely and reliably for five months. The system upgrading is crowned success. What we have been finished is presented in this paper.
59042296
Vacuum chamber and crotch absorber for the SPring-8 storage ring vacuum system
The whole vacuum system for the SPring-8 storage ring is planning to be completely installed in the ring by October 1996. The vacuum chamber for the straight sections consists of a beam chamber and a slot-isolated antechamber in which NEG strips are installed To suppress the chamber deformation at the BPM station due to the pressure difference between the atmospheric pressure and the vacuum, ribs are mounted on the chamber In the bending magnet chamber, a distributed ion pump is also installed. The crotch and absorber have been designed to reduce their RF impedances and the radiation level outside the vacuum chamber. In this paper we present details of the final design for the vacuum chamber, crotch and absorber. The chamber supporting system and the structure of ribs are also described.<<ETX>>