May 12, Tuesday
Visit to Beijing Electron Position Collider and the assembling hall of the Hard X-ray Moderate Telescope Satellite (IHEP)
May 13, Wednesday
Optional Visit to LAMOST telescope in Xinglong (The bus will pass through Jinshanling-Simatai of the Great Wall on the way back. The local organizaing committee recommends the participants taking cable cars when touring the Great Wall )
BEPC II
BEPC II is a two-ring e+e- collider running in the tau-charm energy region (Ecm = 2.0-4.2 GeV), which, with a design luminosity of 1 × 1033 cm-2s-1 at the beam energy of 1.89 GeV, is an improvement of a factor of 100 over its successful predecessor, BEPC. The upgrade will use the existing tunnel, some major infrastructure items, and some of the old magnets. The 202 m long linac of the new machine can accelerate electrons and positrons up to 1.89 GeV with a positron injection rate of 50 mA/min.
Its installation was completed in the summer of 2005 and it has reached most of the design specifications. The collider consists of two 237.5 m long storage rings, one for electrons and one for positrons. They collide at the interaction point with a horizontal crossing angle of 11 mrad and a bunch spacing of 8 ns. Each ring holds 93 bunches with a beam current of 910 mA. The machine will also provide a high flux of synchrotron radiation at a beam energy of 2.5 GeV.
The manufacture of major equipment such as magnets, superconducting RF cavities (with the co-operation of the Japanese high-energy physics laboratory, KEK, and the company MELCO) and quadrupole magnets (with the co-operation of the Brookhaven National Laboratory), as well as the cryogenics system, have been completed, and their installation is under way. The pre-alignment of magnets has made good progress.
Hard X-ray Modulation Telescope
In the new century, it is a frontier topic in both physics and astronomy to explore the fundamental physics processes in the very early universe or in the proximity of black hole horizons. Space astronomical observation is one of the most important paths to address these issues.
IHEP is leading the development of China’s first astronomical satellite, the Hard X-ray Modulation Telescope (HXMT). It was proposed by IHEP scientists Li Tibei and Wu Mei based on their innovative direct demodulation image reconstruction method. The main scientific objectives of HXMT are: (1) to scan the Galactic Plane to find new transient sources and to monitor the known variable sources, and (2) to observe X-ray binaries to study the dynamics and emission mechanism in strong gravitational or magnetic fields. There are three main payloads onboard HXMT, the high energy X-ray telescope (20-250 keV, 5100 cm2), the medium energy X-ray telescope (5-30 keV, 952 cm2), and the low energy X-ray telescope (1-15 keV, 384 cm2).
All these three telescopes are collimated instruments. Using the direct demodulation method and scanning observations, HXMT can obtain X-ray images with high spatial resolution, while the large detection areas of these telescopes also allow pointed observations with high statistics and high signal to noise ratio. It is expected that HXMT will discover a large number of new transient X-ray sources and will study the temporal and spectral properties of accreting black hole and neutron star systems in more details than the previous X-ray missions.
The HXMT satellite is now near the end of the qualification model phase. The manufacturing of the flight model will begin later this year, and the satellite will be launched in 2015.
LAMOST
The Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST), also known as the Guo Shoujing Telescope after the 13th-century Chinese astronomer, is a meridian reflecting Schmidt telescope, located in Xinglong Station, Hebei Province, China. Undertaken by the Chinese Academy of Science, the telescope is planned to conduct a 5-year spectroscopic survey of 10 million Milky Way stars, as well as millions of galaxies. The project’s budget is RMB 235 million yuan.
LAMOST survey contains two main parts: the LAMOST ExtraGAlactic Survey (LEGAS), and the LAMOST Experiment for Galactic Understanding and Exploration (LEGUE) survey of Milky Way stellar structure. The unique design of LAMOST enables it to take 4000 spectra in a single exposure to a limiting magnitude as faint as r=19 at the resolution R=1800, which is equivalent to the design aim of r=20 for the resolution R=500. This telescope therefore has great potential to efficiently survey a large volume of space for stars and galaxies.
