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Identifying the source of the material within coronal mass ejections (CMEs)and understanding CME onset mechanisms are fundamental issues in solar andspace physics. Parameters relating to plasma composition, such as charge statesand He abundance (\ahe), may be different for plasmas originating fromdiffering processes or regions on the Sun. Thus, it is crucial to examine therelationship between in-situ measurements of CME composition and activity onthe Sun. We study the CME that erupted on 2014 September 10, in associationwith an X1.6 flare, by analyzing AIA imaging and IRIS spectroscopicobservations and its in-situ signatures detected by Wind and ACE. We find thatduring the slow expansion and intensity increase of the sigmoid, plasmatemperatures of 9 MK, and higher, first appear at the footpoints of thesigmoid, associated with chromospheric brightening. Then the high-temperatureregion extends along the sigmoid. IRIS observations confirm that this extensionis caused by transportation of hot plasma upflow. Our results show thatchromospheric material can be heated to 9 MK, and above, by chromosphericevaporation at the sigmoid footpoints before flare onset. The heatedchromospheric material can transport into the sigmoidal structure and supplymass to the CME. The aforementioned CME mass supply scenario provides areasonable explanation for the detection of high charge states and elevated\ahe\ in the associated ICME. The observations also demonstrate that thequasi-steady evolution in the precursor phase is dominated by magneticreconnection between the rising flux rope and the overlying magnetic fieldstructure.

The high helium abundance and charge states of the interplanetary CME and its material source on the Sun