中美高校物理本科教育模式的比较与分析

建设具有中国特色的世界一流大学既要充分借鉴西方教育的发展经验,又要结合中国实际.多层次的立体式、融合性创新发展模式是高等教育发展的必然趋势.物理学是诸多学科与技术发展不可或缺的基础,物理教育是全球技术经济发展的主要驱动力.因此,本文以6所中美著名大学为研究对象,分别从物理专业本科教学理念、体制特点、课程设置、教师职称结...     

Subtraction of Spurious Centre-of-Mass Motion in Quark Delocalization and Colour Screening Model

The quark delocalization colour screening model provides an alternative approach for the NN intermediate range attraction, which is attributed to the σ meson exchange in the meson exchange and chiral quark model. However the quark delocalization induces the spurious centre-of-mass motion （CMM）. A method for subtracting the spurious CMM proposed before is applied to the new scattering calculation. The subtraction of the spurious CMM results in an additional NN attraction. The NN scattering data are refitted by a fine tune of the colour screening constant.     

Diquark Structure of Pentaquark in the Quark Delocalization Colour Screening Model

In the framework of quark-delocalization, colour-screening model, the diquark structure of pentaquark θ^＋ is studied in detail under the adiabatic approximation. The calculation is carried out by using the fractional parentage expansion technique, which greatly simplify the calculation of the matrix elements of Hamiltonian. The results show that the ground state of the pentaquark has negative parity rather than positive parity, which was proposed by daffe-Wilczek. However the mass obtained is about 1651 MeV which is still higher than the observed mass 1540 MeV.