The solar injections of near-relativistic (NR) electron events observed at 1 AU appear to be systematically delayed by~10 minutes from the associated flare impulsive phases. We compare inferred injection times of 80 electron events observed by the 3DP electron detector on the Wind spacecraft with 40-800 MHz solar observations by the AIP radio telescope in Potsdam-Tremsdorf, Germany. Other than preceding type Ⅲ bursts, we find no single radio signature characteristic of the inferred electron injection times. The injection delays from the preceding type Ⅲ bursts do not correlate with the 1 AU solar wind β_p or B, but do correlate with densities n_e and inversely with speeds V_(sw), consistent with propagation effects. About half of the events are associated with metric or decametric-hectometric (dh) type Ⅱ bursts, but most injections occur before or after those bursts. Electron events with long (≥2 hr) beaming times at 1 AU are preferentially associated with type Ⅱ bursts, which supports the possibility of a class of shock-accelerated NR electron events.
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