Crossing Symmetry Violation of Inverse Amplitude Method

2002 ◽  
Author(s):  
Isabela P. Cavalcante
Keyword(s):  
Symmetry Violation ◽  
Inverse Amplitude Method ◽  
Crossing Symmetry ◽  
Inverse Amplitude

scholarly journals Systematizing and addressing theory uncertainties of unitarization with the Inverse Amplitude Method

2021 ◽  
Vol 11 (2) ◽  
Author(s):  
Alexandre Salas-Bernárdez ◽  
Felipe Llanes-Estrada ◽  
Juan Escudero-Pedrosa ◽  
José Antonio Oller
Keyword(s):  
Perturbation Theory ◽  
Partial Wave ◽  
Chiral Perturbation Theory ◽  
A Priori ◽  
Resonance Region ◽  
New Physics ◽  
Effective Field ◽  
Chiral Perturbation ◽  
Inverse Amplitude Method ◽  
Inverse Amplitude

Effective Field Theories (EFTs) constructed as derivative expansions in powers of momentum, in the spirit of Chiral Perturbation Theory (ChPT), are a controllable approximation to strong dynamics as long as the energy of the interacting particles remains small, as they do not respect exact elastic unitarity. This limits their predictive power towards new physics at a higher scale if small separations from the Standard Model are found at the LHC or elsewhere. Unitarized chiral perturbation theory techniques have been devised to extend the reach of the EFT to regimes where partial waves are saturating unitarity, but their uncertainties have hitherto not been addressed thoroughly. Here we take one of the best known of them, the Inverse Amplitude Method (IAM), and carefully following its derivation, we quantify the uncertainty introduced at each step. We compare its hadron ChPT and its electroweak sector Higgs EFT applications. We find that the relative theoretical uncertainty of the IAM at the mass of the first resonance encountered in a partial-wave is of the same order in the counting as the starting uncertainty of the EFT at near-threshold energies, so that its unitarized extension should a priori be expected to be reasonably successful. This is so provided a check for zeroes of the partial wave amplitude is carried out and, if they appear near the resonance region, we show how to modify adequately the IAM to take them into account.

scholarly journals Inverse amplitude method and Adler zeros

2008 ◽  
Vol 77 (5) ◽  
Author(s):  
A. Gómez Nicola ◽  
J. R. Peláez ◽  
G. Ríos
Keyword(s):  
Inverse Amplitude Method ◽  
Inverse Amplitude

scholarly journals Unitarization Technics in Hadron Physics with Historical Remarks

Symmetry ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1114
Author(s):  
José Antonio Oller
Keyword(s):  
Effective Range Expansion ◽  
Chiral Perturbation ◽  
Final State ◽  
Hadron Physics ◽  
Coupled Channels ◽  
Inverse Amplitude Method ◽  
Final State Interactions ◽  
Historical Remarks ◽  
K Matrix ◽  
Inverse Amplitude

We review a series of unitarization techniques that have been used during the last decades, many of them in connection with the advent and development of current algebra and later of Chiral Perturbation Theory. Several methods are discussed like the generalized effective-range expansion, K-matrix approach, Inverse Amplitude Method, Padé approximants and the N / D method. More details are given for the latter though. We also consider how to implement them in order to correct by final-state interactions. In connection with this some other methods are also introduced like the expansion of the inverse of the form factor, the Omnés solution, generalization to coupled channels and the Khuri-Treiman formalism, among others.

Sign in / Sign up

Export Citation Format

Share Document