Using multi-band photometric images of M51 and its companion NGC 5195 from ultraviolet to optical and infrared,we investigate spatially resolved stellar population properties of this interacting system with stellar po...Using multi-band photometric images of M51 and its companion NGC 5195 from ultraviolet to optical and infrared,we investigate spatially resolved stellar population properties of this interacting system with stellar population synthesis models.The observed infrared excess(IRX)is used to constrain dust extinction.Stellar mass is also inferred from the model fitting.By fitting observed spectral energy distributions(SEDs)with synthetical ones,we derive two-dimensional distributions of stellar age,metallicity,dust extinction and stellar mass.In M51,two grand-designed spiral arms extending from the bulge show young age,rich metallicity and abundant dust.The inter-arm regions are filled with older,metalpoorer and less dusty stellar populations.Except for the spiral arm extending from M51 into NGC 5195,the stellar population properties of NGC 5195 are quite featureless.NGC 5195 is much older than M51,and its core is very dusty with AV up to 1.67 mag and dense in stellar mass surface density.The close encounters might drive the dust in the spiral arm of M51 into the center of NGC 5195.展开更多
基金Major Program of National Natural Science Foundation of China(No.11890691)supported by the National Basic Research Program of China(973 Program+6 种基金Grant No.2017YFA0402600)the National Natural Science Foundation of China(NSFCGrant Nos.11433005,11673027,11733007,11973038,11320101002 and 11421303)the External Cooperation Program of Chinese Academy of Sciences(Grant No.114A11KYSB20160057)the Two Micron All Sky Survey,which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology,funded by the National Aeronautics and Space Administration and the National Science Foundationa key project of the Telescope Access Program(TAP),which has been funded by National Astronomical Observatories,Chinese Academy of Sciences(the Strategic Priority Research Program“The Emergence of Cosmological Structures”grant No.XDB09000000)the Special Fund for Astronomy from the Ministry of Finance。
文摘Using multi-band photometric images of M51 and its companion NGC 5195 from ultraviolet to optical and infrared,we investigate spatially resolved stellar population properties of this interacting system with stellar population synthesis models.The observed infrared excess(IRX)is used to constrain dust extinction.Stellar mass is also inferred from the model fitting.By fitting observed spectral energy distributions(SEDs)with synthetical ones,we derive two-dimensional distributions of stellar age,metallicity,dust extinction and stellar mass.In M51,two grand-designed spiral arms extending from the bulge show young age,rich metallicity and abundant dust.The inter-arm regions are filled with older,metalpoorer and less dusty stellar populations.Except for the spiral arm extending from M51 into NGC 5195,the stellar population properties of NGC 5195 are quite featureless.NGC 5195 is much older than M51,and its core is very dusty with AV up to 1.67 mag and dense in stellar mass surface density.The close encounters might drive the dust in the spiral arm of M51 into the center of NGC 5195.
