Combustor, combustor system, and gas turbine

A combustor comprising:

• a substrate that extends in a direction orthogonal to a combustor axis;
• a plurality of premixing pipes that extend to penetrate the substrate and that jet a premixed gas generated by mixing a fuel with air, which is introduced from an upstream side, from an opening portion on a downstream side;
• and
• a temperature detection circuit that is provided on the substrate and that extends in the direction orthogonal to the combustor axis to pass around each of the premixing pipes, wherein
• the temperature detection circuit has a starting point and an end point that are output terminals of the temperature detection circuit and has a plurality of contact points formed by alternately connecting a plurality of positive element lines and a plurality of negative element lines from a starting point side toward an end point side, and
• the temperature detection circuit has an intermediate point that is an output terminal between the starting point and the end point.