摘要
The post-AGB star J004441 is the first and the only one CEMP-r/s star found in SMC. Herein, we investigate the observed abun- dance pattern of the heavy elements using our parametric model. A consistent fitting results was obtained for the sample star. Based on the low r = 0.08, the s-process nucleosynthesis occurred in the interior is supposed to belong to the single neutron-exposure v9 ,1/2 mbarn-1 supports a higher efficiency of the s-process nucleosynthesis relative to event. The median value of τ0 =0.44（T9/0.348）mbarn-1 supports a higher efficiency of the s-process nucleosynthesis relative to J004441 than that of the solar system, however, the value is not sufficiently high to favor the formation of a lead star. Thus, J004441 does not belong to lead star group. The large Cs value of J004441 supports the intrinsic characteristic of the s-enrichment. The Cr value is similar with that found in halo CEMP-r/s stars, which indicates that the r-process contributions is critical during heavy element enrichment. This star has a metallicity of [Fe/H] = -1.34, which is larger than that of Galaxy halo CEMP-r/s stars. The reason may be because of the different history of metallicity enrichment between the SMC and the Galaxy halo.
The post-AGB star J004441 is the first and the only one CEMP-r/s star found in SMC.Herein,we investigate the observed abundance pattern of the heavy elements using our parametric model.A consistent fitting results was obtained for the sample star.Based on the low r=0.08,the s-process nucleosynthesis occurred in the interior is supposed to belong to the single neutron-exposure event.The median value ofτ0=0.44(T90.348)1/2mbarn-1supports a higher efficiency of the s-process nucleosynthesis relative to J004441 than that of the solar system,however,the value is not sufficiently high to favor the formation of a lead star.Thus,J004441does not belong to lead star group.The large Csvalue of J004441 supports the intrinsic characteristic of the s-enrichment.The Crvalue is similar with that found in halo CEMP-r/s stars,which indicates that the r-process contributions is critical during heavy element enrichment.This star has a metallicity of[Fe/H]=-1.34,which is larger than that of Galaxy halo CEMP-r/s stars.The reason may be because of the different history of metallicity enrichment between the SMC and the Galaxy halo.
基金
supported by the National Natural Science Foundation of China(Grant Nos.U1231119,11273011,11390371,11003002,11021504 and 10973016)
the China Postdoctoral Science Foundation(Grant No.2013M531587)
the Natural Science Foundation of Hebei Province(Grant No.A2011205102)
