Nonleptonic decays of charmed pseudoscalar mesons. [Weak Hamiltonian]

NONLEPTONIC DECAYS OF CHARMED MESONS INTO TWO PSEUDOSCALAR MESONS

Modern Physics Letters A ◽

10.1142/s0217732393001793 ◽

1993 ◽

Vol 08 (22) ◽

pp. 2079-2086 ◽

Cited By ~ 5

Author(s):

ASHOK DAS ◽

VISHNU S. MATHUR

Keyword(s):

Charmed Meson ◽

Nonleptonic Decay ◽

Charmed Mesons ◽

Dominance Model ◽

Vector Dominance ◽

Pseudoscalar Mesons ◽

Factorization Model ◽

Nonleptonic Decays ◽

Decays Of Charmed Mesons

We investigate the nonleptonic decay of charmed meson into two pseudoscalar mesons using the vector-dominance model, and compare the results with those obtained from the factorization model. In particular, we discuss the role of the annihilation diagrams in the two models.

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The low-energy effective theory of axions and ALPs

Journal of High Energy Physics ◽

10.1007/jhep04(2021)063 ◽

2021 ◽

Vol 2021 (4) ◽

Author(s):

Martin Bauer ◽

Matthias Neubert ◽

Sophie Renner ◽

Marvin Schnubel ◽

Andrea Thamm

Keyword(s):

High Energy ◽

New Physics ◽

Mass Scale ◽

Low Energy ◽

Effective Theory ◽

Loop Order ◽

Flavor Changing ◽

Effective Lagrangian ◽

Anomalous Dimensions ◽

Pseudoscalar Mesons

Abstract Axions and axion-like particles (ALPs) are well-motivated low-energy relics of high-energy extensions of the Standard Model, which interact with the known particles through higher-dimensional operators suppressed by the mass scale Λ of the new-physics sector. Starting from the most general dimension-5 interactions, we discuss in detail the evolution of the ALP couplings from the new-physics scale to energies at and below the scale of electroweak symmetry breaking. We derive the relevant anomalous dimensions at two-loop order in gauge couplings and one-loop order in Yukawa interactions, carefully considering the treatment of a redundant operator involving an ALP coupling to the Higgs current. We account for one-loop (and partially two-loop) matching contributions at the weak scale, including in particular flavor-changing effects. The relations between different equivalent forms of the effective Lagrangian are discussed in detail. We also construct the effective chiral Lagrangian for an ALP interacting with photons and light pseudoscalar mesons, pointing out important differences with the corresponding Lagrangian for the QCD axion.

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