# Arrow convention for neutral particles in Feynman diagram

In a Feynman diagram, the arrows on the charged particles are along the direction of negative charge flow. As a result, the arrow is not always directed from the vertex of creation and not always directed towards the vertex of annihilation. The antineutrino and neutron in $$\beta$$-decay carry no charge. What is the convention of arrow in the Feynman diagram of $$\beta$$-decay? Sometimes I see arrows on neutral particles and sometimes don't. When arrows are given, they point the direction towards the vertex where neutron is destroyed and towards the vertex where the antineutrino is created. What is the solution?