This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
2013:groups:higgs:ehd [2013/06/19 19:22] alexandre.arbey |
2013:groups:higgs:ehd [2013/06/30 22:13] (current) lorenzo.basso |
||
---|---|---|---|
Line 1: | Line 1: | ||
**Exotic Higgs Decays** | **Exotic Higgs Decays** | ||
- | Interested people: Adam, Roberto, Filip, Jack Gunion, Sabine, Grégory, Beranger, Kirtimaan, Yun Jiang, Aoife, Lorenzo, Alex A., Nazila... (please add your name!) | + | Interested people: Adam, Roberto, Filip, Jack Gunion, Sabine, Grégory, Beranger, Kirtimaan, Yun Jiang, Aoife, Lorenzo, Alex A., Nazila, Andreas-1, Andreas-2, Giacomo, Aldo... (please add your name!) |
Finding exotic (not predicted by the SM) Higgs decays could be the shortest route to new physics. | Finding exotic (not predicted by the SM) Higgs decays could be the shortest route to new physics. | ||
Line 28: | Line 28: | ||
E.g these decays could be induced by the operator -c|H|^2/v^2 F_{\mu \nu} X_{\mu \nu} where | E.g these decays could be induced by the operator -c|H|^2/v^2 F_{\mu \nu} X_{\mu \nu} where | ||
X_\mu is a dark vector boson that subsequently decays to the DM particles. gamma+MET decays could also arise from the cascade decays in h-> neutralino+gravitino -> 2xgravitino+gamma in SUSY, see 1203.4563. | X_\mu is a dark vector boson that subsequently decays to the DM particles. gamma+MET decays could also arise from the cascade decays in h-> neutralino+gravitino -> 2xgravitino+gamma in SUSY, see 1203.4563. | ||
- | Z+MET decays can occur e.g. in inverse see-saw models (ref?) as a cascade decay h-> nu N -> nu Z nu. | + | Z+MET decays can occur e.g. in inverse see-saw models (see e.g., 1209.4803) as a cascade decay h-> nu N -> nu Z nu. |
- | To do: check the constraints on the effective operator, find the maximum allowed branching fraction, check whether some LHC searches (monophotons? mono-Z?) could pick up this decay, devise experimental strategy. | + | To do: check the constraints on the effective operator, find the maximum allowed branching fraction, check whether some LHC searches (monophotons? mono-Z?) could pick up this decay, devise experimental strategy. Check contraints from existing H-> ZZ |
+ | |||
+ | __Interested people:__ Adam, Lorenzo, ... | ||
Line 38: | Line 40: | ||
- flavor violating decays to quarks, probably hopeless given the constraints from flavor violation, see e.g. 1209.1397 | - flavor violating decays to quarks, probably hopeless given the constraints from flavor violation, see e.g. 1209.1397 | ||
- | - lepton flavor violating decays (h->tau mu, h-> tau e, h-> mu e), the first two are promising, see e.g. 1209.1397. These decays are searched for by experiment and has been quite thoroughly studied theoretically, so probably nothing to do. | + | - lepton flavor violating decays (h->tau mu, h-> tau e, h-> mu e), the first two are promising, see e.g. 1209.1397. Also, as before, lepton flavour violating decays can occur in inverse see-saw models (see e.g., 1209.4803) as a cascade decay h-> nu N -> nu l W -> nu l l' nu', where the flavour of l and l' are not related. These decays are searched for by experiment and has been quite thoroughly studied theoretically, so probably nothing to do. |
- cascade decays h->X a -> X f fbar, where X is invisible. | - cascade decays h->X a -> X f fbar, where X is invisible. | ||
Note that this decay cannot be realized in the 2HDM+singlet models in which we require X to be a single additional singlet that is a stable DM candidate by means of imposing Z_2 symmetry so that single S terms are absent in the Lagrangian. In this case, X would have to be two S states, i.e. H->SS h or something of the sort. This would yield invisible + 2 SM particles. A related scenario is H->h h where one h decays to f fbar and the other h decays to SS, i.e. h has a mixture of regular and invisible decays. | Note that this decay cannot be realized in the 2HDM+singlet models in which we require X to be a single additional singlet that is a stable DM candidate by means of imposing Z_2 symmetry so that single S terms are absent in the Lagrangian. In this case, X would have to be two S states, i.e. H->SS h or something of the sort. This would yield invisible + 2 SM particles. A related scenario is H->h h where one h decays to f fbar and the other h decays to SS, i.e. h has a mixture of regular and invisible decays. | ||
- | To do: concrete models, existing constraints and experimental strategies. | + | To do: concrete models, existing constraints and experimental strategies. In particular, interesting to recast the SUSY dilepton+MET searches in this context. |
+ | |||
+ | __Interested people:__ Jack, Aoife, Andreas, Lorenzo | ||
--------------------------------------------------- | --------------------------------------------------- | ||
3 particle: | 3 particle: | ||
Line 51: | Line 56: | ||
To do: existing constraints, e.g. from h->ZZ*4l; limits on F from direct searches (LEP and LHC), precision contraints on F, collider strategies | To do: existing constraints, e.g. from h->ZZ*4l; limits on F from direct searches (LEP and LHC), precision contraints on F, collider strategies | ||
+ | |||
+ | __Interested people:__ Aldo, Giacomo, Aldo | ||
- h -> Z/A X - > Z/A f fbar where X is an intermediate boson , and f could be b, tau, mu, e, etc. | - h -> Z/A X - > Z/A f fbar where X is an intermediate boson , and f could be b, tau, mu, e, etc. |