Details

Autor(en) / Beteiligte

• Starkey, M. J.
• Fuselier, S. A.
• Desai, M. I.
• Schwartz, S. J.
• Russell, C. T.
• Wei, H.
• Madanian, H.
• Mukherjee, J.
• Wilson III, L. B.

Titel

MMS Observations of Energized He+ Pickup Ions at Quasiperpendicular Shocks

Ist Teil von

• The Astrophysical journal, 2021-06, Vol.913 (2), p.112

Ort / Verlag

Goddard Space Flight Center: The American Astronomical Society

Erscheinungsjahr

2021

Link zum Volltext

Quelle

Elektronische Zeitschriftenbibliothek (Open access)

Beschreibungen/Notizen

• Accelerated He+ PUIs, downstream of quasi-perpendicular shocks, are studied as 10a function of the fast mode Mach number (Mf) and shock obliquity (θBn).We analyze quasi-perpendicular shocks with Mach numbers in the range [1, 7] observed by the Magnetospheric MultiScale (MMS) mission, and compare upstream and downstream He+ velocity distribution functions (VDFs). For each shock event, we characterize the upstream PUI distribution and derive reduced 1D velocity distributions for the selected upstream and downstream intervals. We also compare the upstream to downstream ratio of spectral indices, computed from the He+ perpendicular distributions, to Mf and θBn. We find a positive correlation between this spectral index ratio and Mf, which suggests that perpendicular energization of He+ PUIs is enhanced as the shock becomes stronger. These results inform modeling efforts of PUIs and shock acceleration processes, particularly those taking place at the termination shock.