SIMBAD references

We present high-resolution Chandra observations of shrapnel A in the vicinity of the Vela supernova remnant. The Chandra image reveals a bright X-ray region at the head position of shrapnel A and a fainter extended tail. The spectral analysis shows that the plasma is in a condition of nonequilibrium ionization. The abundance of O is 0.34^+0.12_–0.08 times that of the solar value, whereas that of Si is 3⁺²_–1 times solar, showing an anomalous abundance ratio for the two elements. The ionization timescale indicates that the shrapnel had been heated up about 10⁴ yr ago. We confirm that the pressure in the head region is ≃10 times higher than that in the tail region, which is not explained by a simple blast-wave model. These facts strongly support the view that shrapnel A is a fragment of the progenitor star created in the supernova explosion.