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Updated: Jul 6, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Search for flavor-changing-neutral-current d meson decays.
V M Abazov1, B Abbott, M Abolins
1Joint Institute for Nuclear Research, Dubna, Russia.
Physical Review Letters
|March 21, 2008
Summary
Researchers investigated the rare flavor-changing neutral current process in charm quarks. They found no evidence for the D+ to pi+ mu+ mu- decay, setting a new stringent limit on this rare particle physics process.
Area of Science:
- Particle Physics
- High-Energy Physics
- Standard Model Physics
Background:
- Flavor-changing neutral current (FCNC) processes are rare in the Standard Model.
- Charm quark transitions provide a unique window to probe new physics beyond the Standard Model.
- Previous searches for c -> u mu+ mu- transitions have yielded limited results.
Purpose of the Study:
- To search for the flavor-changing neutral current decay D+ -> pi+ mu+ mu-.
- To set a stringent upper limit on the branching fraction of this decay.
- To constrain new physics scenarios contributing to charm quark transitions.
Main Methods:
- Analysis of 1.3 fb^-1 of pp collisions at sqrt(s) = 1.96 TeV.
- Utilized data from the D0 detector at the Fermilab Tevatron Collider.
- Searched for D+ -> pi+ mu+ mu- decays in the dimuon invariant mass spectrum, excluding the phi resonance region.
Main Results:
- Clear indications of charged-current mediated D(s)+ and D+ decays to phi pi+ (via mu+ mu- pi+) were observed with >4 sigma significance.
- No evidence for the neutral-current decay D+ -> pi+ mu+ mu- was found.
- An upper limit on the branching fraction was set: B(D+ -> pi+ mu+ mu-) < 3.9 x 10^-6 at 90% C.L.
Conclusions:
- The study provides the most stringent constraint to date on new phenomena in the c -> u mu+ mu- transition.
- The null result places significant limits on extensions to the Standard Model, such as supersymmetry or extra gauge bosons.
- This result contributes to the ongoing effort to precisely measure rare charm decays and probe fundamental physics.
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