An X-ray Study of the Pulsar Wind Nebulae Discovered in the Very High Energy Gamma-ray Band

摘要

We studied nature of the pulsar wind nebulae (PWNe) whose association to the TeV gamma-ray sources is suspected. A total of 16 PWNe was selected and their X-ray data were analyzed. We found that the parameters of the TeV associated PWNe are basically same as those not detected in the TeV band. Although the energy loss time scale of the X-ray emitting, high-energy electrons in the PWNe is only ~2 kyr, we found that the size of the X-ray emission region of the TeV PWNe keeps increasing up to ~100 kyr. Two possibilities are discussed for this continued increase of the X-ray sizes.