## OPEDelta

`OPEDelta` is a lightlike axial vector as used e.g. in the operator product expansion in QCD.

### See also

[Overview](Extra/FeynCalc.md), [Twist2QuarkOperator](Twist2QuarkOperator.md).

### Examples

```mathematica
FV[OPEDelta, \[Mu]] 
 
Contract[% %]
```

$$\Delta ^{\mu }$$

$$0$$

```mathematica
SP[OPEDelta, OPEDelta]
```

$$0$$