Heliopause radio emission scenario
نویسندگان
چکیده
Heliospheric (HSP) radio emission detected by the Voyager spacecraft between 1.8 kHz and 3.6 kHz from the distant heliosphere is interpreted as emission generated close to and at the heliopause (HP), the interface between the ionised very local interstellar (LIC) gas and the supersonic solar wind (SW) stream. Radio emission is assumed to be triggered by secondary charge exchange ionisation of interstellar neutrals and subsequent generation of lower hybrid (LH) waves. These waves nonlinearly accelerate electrons into beams along the spiral compressed heliosheath (HS) magnetic field B. Langmuir waves locally generated by these beams may be responsible for the observed emission. Under quiet conditions the emission is at marginally high frequency for observation. Under disturbed conditions the plasma density may be high enough to explain the Voyager observations. In this mechanism B plays a crucial role.
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