Multi-point observations of quasi-perpendicular interplanetary shock structures

We study structures of quasi-perpendicular interplanetary shocks observed by the Wind and DSCOVR spacecraft at L1. The continuous high-time resolution DC-magnetometer measurements (11 vectors/s on Wind and 50 vectors/s on DSCOVR) allow identification of the shock ramp structure and magnetosonic-whistler precursor waves, typically observed at up to several Hz in the spacecraft frame. We analyze the shock structure dependence on the interplanetary shock parameters and on the spacecraft separation. We also identify Wind observed interplanetary shocks without precursors resulting from magnetic field under-sampling to determine the fraction of unresolved precursors.