Bound states and fermiophobic unparticle oblique corrections to the photon

Journal Article · Mon Feb 01 00:00:00 EST 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.035001· OSTI ID:21409196

Thalapillil, Arun M ^[1]

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1. Enrico Fermi Institute and Department of Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, Illinois 60637 (United States)

We study the effects of fermiophobic scalar/pseudoscalar oblique corrections on bound state energy levels in muonic atoms. To make the treatment sufficiently general, while including ordinary scalar and axionlike pseudoscalar fields as special cases, we consider unparticle scalar/pseudoscalar operators with couplings predominantly to photons. We derive the relevant vacuum polarization functions and comment on the functional forms of the unparticle Uehling potentials for various scaling dimensions in the point nucleus and finite nucleus approximations. It is estimated that for an infrared fixed point near the scale of electroweak-symmetry breaking, in the low TeV range, and natural values for the model parameters, the energy shifts in the low-lying muonic-lead transitions are typically of the order of a few times 0.1 eV to a few times 0.01 eV. The energy level structures of the unparticle Uehling shifts are inferred using general methods for the scalar and pseudoscalar cases and it is shown that the two cases contribute to the energy shifts with the same sign. It is shown that this conclusion is not changed even when scale invariance is broken and is in fact relatively insensitive to the scale at which it is broken. It is pointed out nevertheless that the estimated magnitude of the unparticle Uehling shift (based on some natural values for the model parameters) is a factor of 1000-10000 below the discrepancy in QED/nuclear theory and precision muonic-lead spectroscopy from about two decades ago. We briefly comment on scenarios where the unparticle induced energy shift, if it exists, may be experimentally measurable. One possibility in this direction is if the UV sector, from which the unparticle sector arises, has a large number of fermions. Comments are also made on the possibility of further studying muonic atoms, as a probe for beyond-standard-model physics, in the context of forthcoming experiments, such as those probing lepton flavor violation through coherent muon-electron conversions. For completeness we explore some of the astrophysical and cosmological consequences of a fermiophobic scalar/pseudoscalar unparticle sector. In the fermiophobic context we also estimate a minimum value for the conformal invariance breaking scale.

• OSTI ID: 21409196
• Journal Information: Physical Review. D, Particles Fields, Vol. 81, Issue 3; Other Information: DOI: 10.1103/PhysRevD.81.035001; (c) 2010 The American Physical Society; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
APPROXIMATIONS
ASTROPHYSICS
BOUND STATE
CONFORMAL INVARIANCE
CONVERSION
CORRECTIONS
COUPLING
ELECTRONS
ENERGY LEVELS
FLAVOR MODEL
MUONIC ATOMS
MUONS
NUCLEAR THEORY
PHOTONS
QUANTUM ELECTRODYNAMICS
SCALE INVARIANCE
SCALING
SPECTROSCOPY
STANDARD MODEL
SYMMETRY BREAKING
TEV RANGE
ATOMS
BOSONS
CALCULATION METHODS
COMPOSITE MODELS
ELECTRODYNAMICS
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
FIELD THEORIES
GRAND UNIFIED THEORY
INVARIANCE PRINCIPLES
LEPTONS
MASSLESS PARTICLES
MATHEMATICAL MODELS
PARTICLE MODELS
PHYSICS
QUANTUM FIELD THEORY
QUARK MODEL
UNIFIED GAUGE MODELS