Statistical Comparison of Small Flux Ropes in Different Types of Solar Wind

Based on the list of small flux ropes with the duration from 9 minute to 36 hours developed by Hu et al., 2018 through an automated detection algorithm, together with the ICME and SIR catalog that we recently established, this work studied and compared the properties of small flux ropes in different types of solar wind (ICME body, ICME sheath, SIR, back ground solar wind) from 2005 to 2015. The main findings of this work are as follows: (1) The number of small magnetic ropes in ICME bodies, ICME sheaths, SIRs and background solar wind account for 5%, 3%, 36% and 56% respectively. (2) Small flux ropes in ICME bodies have longer duration than small flux ropes in other type of solar wind. (3) The magnetic field and plasma parameters of the different types of small flux ropes are basically consistent with the solar wind environment they are in, which may mean that they are locally generated. (4) The mean abundance ratio Fe/O in these flux ropes is about 2 times the coronal value.