Effective range expansion in various scenarios of EFT($\notpi$)

TL;DR

This paper compares effective range expansion parameters across different EFT(π̸) scenarios using rigorous solutions, highlighting the viability of conventional power counting over unconventional approaches based on PSA data.

Contribution

It provides a detailed comparison of EFT(π̸) scenarios with rigorous solutions, favoring conventional power counting for nonperturbative regimes.

Findings

Unconventional power counting is disfavored by PSA data.

Conventional power counting with elaborate renormalization is more promising.

Rigorous solutions clarify the differences between EFT scenarios.

Abstract

Using rigorous solutions, we compare the ERE parameters obtained in three different scenarios of EFT($\notpi$) in nonperturbative regime. A scenario with unconventional power counting (like KSW) is shown to be disfavored by the PSA data, while the one with elaborate prescription of renormalization but keeping conventional power counting intact seems more promising.