What would happen if the Higgs boson and the $Z$ boson collided?

Question

I am thinking the $z$ boson would remain with the combined mass of both the $Z$ boson and the Higgs boson. This is because the Higgs boson is a spin-0 boson and the $Z$ boson is a spin-1 boson.

ls also this https://physics.stackexchange.com/questions/266741/feynman-diagram-elementary-vertex-with-4-lines — anna v, May 09 '20 at 03:54

score 2 · Accepted Answer · answered May 08 '20 at 16:32

The Standard Model allows two possibilities: The $Z$ can absorb the Higgs, or they can scatter off each other. The first corresponds to a three-particle $HZZ$ vertex in a Feynman diagram and the second to a four-particle $HHZZ$ vertex. You can see these two possible vertices in the answer to this question.

Cosmas Zachos · Answer 2 · 2020-05-09T00:34:34.433

2

You seem to believe particles absorb/trade masses in reactions. They only trade energy and momentum.

For a real Z absorbing a real h to end up with a real Z, you'd need both energy and momentum to balance across the reaction. In the center-of momentum frame of the input particles Z and H you'd then have a total energy $$ E=\sqrt{m_Z^2 + p^2} + \sqrt{m_h^2 + p^2}, $$ and zero total momentum, by frame choice. The output Z would then be at rest, with total energy $E=m_Z$.

However, for absolutely any p, including 0, $$ m_Z\neq \sqrt{m_Z^2 + p^2} + \sqrt{m_h^2 + p^2}, $$ so your reaction will not go.

edited May 09 '20 at 00:34

answered May 08 '20 at 16:54

Cosmas Zachos

62,595

The masses count as energy. I mean energy in the masses get absorbed. – MiltonTheMeme May 08 '20 at 17:14
What about 2 z bosons – MiltonTheMeme May 08 '20 at 17:14
1

There is no HZZZ vertex in the SM, and I believe there is no tree diagram you can cook up for this, as per here. – Cosmas Zachos May 08 '20 at 18:03
@Roghan Appreciative of the key point? – Cosmas Zachos May 13 '20 at 14:01

What would happen if the Higgs boson and the $Z$ boson collided?

2 Answers2