We consider a massless higher spin field theory within the BRST approach and construct a general off-shell cubic vertex corresponding to irreducible higher spin fields of helicities $s_1,s_2,s_3$. Unlike the previous works on cubic vertices, which do not take into account of the trace constraints, we use the complete BRST operator, including the trace constraints that describe an irreducible representation with definite integer helicity. As a result, we generalize the cubic vertex found in [14] and calculate the new contributions to the vertex, which contain additional terms with a smaller number space-time derivatives of the fields as well as the terms without derivatives.

我们在 BRST 方法中考虑了无质量的高自旋场理论，并构建了一个通用的壳外立方顶点，对应于不可约的高自旋螺旋场 ${秒}_1,{秒}_2,{秒}_3$. 与之前在三次顶点上的工作不考虑迹约束不同，我们使用完整的 BRST 算子，包括描述具有确定整数螺旋度的不可约表示的迹约束。因此，我们概括了 [14] 中发现的三次顶点并计算了对顶点的新贡献，其中包含具有较小数量的场时空导数的附加项以及没有导数的项。