Simulator: Higgs production from a top KK tower
Compare the leading top-KK correction to Higgs production with finite-tower and resummed low-energy-theorem calculations under a stated domain policy.
Control names are kept as they appear in the application. Start with a reference, change one input at a time, and retain the assumptions with your result.
What this tool is for
Use this to study one isolated production-rate mechanism without treating it as a complete GHU signal calculation. The finite sum tests how many KK terms are needed, while the resummed comparison asks a different approximation question.
First steps
- Select Higgs production in the Simulator model selector.
- Start from the Carson–Okada reference and read its historical rate window.
- Vary the KK scale, top mass or numerical cutoff separately.
- Compare numerical truncation, the leading/resummed difference and the conditional allowed interval.
Controls and inputs
| Control | Meaning | Try this |
|---|---|---|
| KK scale and top mass | Set the ratio x = m_t/M_KK governing this reference correction. Use the displayed units. | Increase the KK scale with the top mass fixed. |
| KK cutoff | Sets how many terms enter the finite leading tower. | Increase it while keeping the physical inputs fixed and read the tail bound. |
| Reference or custom rate window | Defines the interval against which the rate is compared. | Read both window edges; do not interpret a custom window as a new experimental likelihood. |
Reading the results
| Result | Meaning |
|---|---|
| Leading and resummed rates | Two calculations with different approximation scope inside the same top-only reference. |
| Finite-tower tail bound | Bounds the omitted leading-sum contribution, not missing particles or higher-order physical effects. |
| Conditional scale interval | Intersects the chosen rate window with the laboratory policy x ≤ 0.2. |
The historical window reproduces a source benchmark; a custom window is a user scenario with no assigned confidence level. The numerical tail and the small-x expansion comparison do not quantify all physical theory uncertainty.
Worked example
Separate truncation from approximation
- Use the historical reference inputs.
- Increase the cutoff and inspect the finite-tower tail.
- Compare the converged leading rate with the resummed rate.
- Change the user window and observe that the conditional interval changes without changing the rate formula.
What to expect: A smaller numerical tail does not remove the difference between physical approximations.
Formulas and conventions
R_gg = [1 − (π²/3)(m_t/M_KK)²]²
The leading top-only reference rate from Carson–Okada under the stated spectrum and approximation.
A_LET = πx cot(πx), x = m_t/M_KK
The independently resummed determinant low-energy-theorem amplitude. Its square is not a full finite-mass loop calculation.
Scope and limitations
- The x ≤ 0.2 policy defines the displayed working domain; it does not promise a uniform physical accuracy.
- Branching fractions and additional coloured particles are outside this mode.
- The historical scale bound is not presented as a current global exclusion.
If something is unclear
The current rate or verdict is withheld.
Check whether x exceeds the displayed domain policy.
The finite sum converges but differs from the resummed result.
Read the distinction between truncation of the leading sum and the small-x expansion within the low-energy theorem.
Terms used here
Sources and attribution
Current instrument guide. Archived editions retain their own scope.
Back to top