报告题目：Constraining the Rastall parameters in static spacetimes with galaxy-scale strong gravitational lensing    

　　报告人：李瑞（云南天文台，博士） 

　　摘要：Recently, Rastall gravity is undergoing a significant surge in popularity. We naturally obtain a power-law total mass-density profile for the inner regions (within several effective radius) of early-type galaxies (ETGs) from the space-time structures which are described by the static spherically-symmetric solutions of Rastall gravity under the assumption of the perfect fluid matter. We find that in the inner region of ETGs, the Rastall dimensionless parameter β = κλ determines the mass distribution. We then use 118 galaxy-galaxy strong gravitational lensing systems to constrain the Rastall dimensionless parameter β. We find that the mean value of β for total 118 ETGs isβ = 0.163±0.001(68% CL) with a minor intrinsic scatter of δ = 0.020±0.001. Our work observationally illustrates the physical meaning of theRastall dimensionless parameter in galaxy scale. From the Newtonian approximation of Rastall gravity, we also find that an absolute isothermal mass distribution for ETGs is not allowed in the Rastall gravity framework.     

　　报告时间：4月23日，上午10：00 

　　报告地点：紫台仙林园区5号楼216会议室 

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