National Astronomical Observatories

      Chinese Academy of Sciences

      A20 Datun Road, Chaoyang

      Beijing 100012

      P.R.China

      Email: xuelei@bao.ac.cn

      Fax：86-10-64850103

      Title of talk: Constrain the dark matter property with cosmic ionization history

      Abstract: The cosmic ionization history provides a useful tool to constrain the decay and annihilations of dark matter particles. Even a small fraction of dark matter particles decayed or annihilated during the cosmic dark age can provide sufficient energy to affect the ionization state of the baryonic gas. The ionization history of the Universe can be probed by CMB observations. Using current CMB data, we obtain constraint on the decay and annihilation rate of dark matter particles.

2.  Chu, Yao-Quan  (褚耀泉)

      Center for Astrophysics

      University of Science and Technology of China

      96 Jinzai Lu

      Hefei, Anhui 230026

      P.R.China

      Email: yqchu@ustc.edu.cn

      Fax: 86-551-3631760

     Title of talk: The Scientific Prospect and Project Progress of the LAMOST

     Abstract: focal length of 20-meter and a field of view of 5-degree. Using active optics technique to control its reflecting corrector makes LAMOST a unique astronomical instrument in combining a large aperture with a wide field of view. The available large focal plane of 1.75-meter in diameter may accommodate up to 4000 fibers, by which the collected light of distant and faint celestial objects is fed into the spectrographs, promising a very high spectrum acquiring rate of several ten-thousands of spectra per night. The telescope will be located at the Xinglong Station of Beijing Astronomical Observatory, Chinese Academy of Sciences, as a national facility open to the whole astronomical community. The spectroscopic survey carried out by LAMOST of tens of millions of galaxies and others will make substantial contribution to the study of extra-galactic astrophysics and cosmology, such as galaxies, quasars and the large-scale structure of the universe. Its spectroscopic survey of large number of stars will make substantial contribution to the study of stellar astrophysics and the structure and evolution of The Galaxy. Its spectroscopic survey combining with the surveys in other wavebands, such as radio, infrared, X-ray and -ray will make substantial contribution to the cross-identification of multi-waveband of celestial objects.