1. A heater, comprising:a ceramic body having a pillar or cylindrical shape;
a heat generating resistor disposed in the ceramic body;
a metallic layer which is disposed on an outer peripheral surface of the ceramic body and extends in a circumferential direction thereof;
a flange which is an annular member disposed on the metallic layer,
comprising a bottom surface facing to the outer peripheral surface and a side surface connected to the bottom surface,
wherein the bottom surface and the side surface are bonded to the metallic layer with a bonding material; and
a metallic wire which extends in the circumferential direction along the side surface, and is bonded to the side surface and the metallic layer in a circumferential direction with the bonding material.