Unnuclear physics: Conformal symmetry in nuclear reactions
Hans-Werner Hammer1,2,3, Dam Thanh Son4,5,6
1Department of Physics, Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany; hans-werner.hammer@physik.tu-darmstadt.de dtson@uchicago.edu.
Summary
We introduce the unnucleus, a nonrelativistic concept from unparticle physics, observed in nuclear reactions. This finding predicts a power-law behavior in inclusive cross-sections for specific neutron emission energies.
Area of Science:
- Nuclear Physics
- Quantum Field Theory
- Particle Physics
Background:
- Georgi's unparticle physics proposes hypothetical relativistic particles.
- Nonrelativistic conformal field theory provides a framework for new field definitions.
- Nuclear reactions offer potential experimental realizations of theoretical concepts.
Purpose of the Study:
- To define and investigate a nonrelativistic version of unparticle physics, termed the "unnucleus."
- To analyze scattering processes involving an unnucleus and predict observable signatures.
- To connect theoretical predictions with experimental nuclear reactions and suggest measurement opportunities.
Main Methods:
- Definition of the unnucleus as a field in nonrelativistic conformal field theory.
- Formal analysis of scattering cross-sections as a function of recoil energy.
- Identification of specific nuclear reactions (e.g., 6He, 3H) as experimental analogs.
- Combination with fermion unitarity properties in a harmonic trap.
Main Results:
- The differential cross-section exhibits a power-law singularity determined by the unnucleus's conformal dimension.
- The unnucleus is approximated in nuclear reactions with few-neutron emission (0.1-5 MeV).
- A power-law behavior for inclusive cross-sections in this kinematic regime is predicted.
- Predictions are verified against existing effective field theory and model calculations.
Conclusions:
- The unnucleus provides a realizable, nonrelativistic counterpart to relativistic unparticles.
- Nuclear reactions involving neutron emission serve as experimental platforms for studying unnuclei.
- Further measurements at radioactive beam facilities can probe unnuclei properties.
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