Yu-Feng Luo | Searcharxiv

arXiv2026

The orbital parameters of gamma-ray binary PSR~J2032+4127

PSR~J2032+4127 is the only one of gamma-ray binary, that exhibits pulsations in gamma-ray. Previous research has indicated that the pulsar and the Be star MT91 213 orbit each other in a highly eccentric orbit with an extremely long period, with the pulsar reaching its periastron on November 13, 2017. Since its launch, the \fermi{} satellite has been monitoring this pulsar for 16 years, covering the 8 years before and the 8 years after the pulsar passed its periastron. Using these data, we present an analysis of pulse arrival times, and precisely determine the orbital parameters for the first time: the orbital period of $P_{\rm orb} \sim 52.3$ yr, the eccentricity of $e \sim 0.98$, the semimajor axis of $a$sin$i \sim 25.3$ AU, and the orbital inclination of $\sim$ 47.1$^\circ$ -- 55.1$^\circ$. We also reveal another small glitch occurred in 2021, MJD $\sim$ 59500.

astro-ph.HE↗

arXiv2023

Approximate N$^5$LO Higgs boson decay width $\Gamma(H\to\gamma\gamma)$

The precision and predictive power of perturbative QCD (pQCD) prediction depends on both a precise, convergent fixed-order series and a reliable way of estimating the contributions of unknown higher-order (UHO) terms. It has been shown that by applying the Principal of Maximum Conformality (PMC), which applies the renormalization group equation recursively to set the effective magnitude of $\alpha_s$ of the process, the remaining conformal coefficients will be well matched with the corresponding $\alpha_s$ at each orders, leading to a scheme-and-scale invariant and convergent perturbative series. Thus different from conventional scheme-and-scale dependent fixed-order series, the PMC series will provide a more reliable platform for estimating UHO contributions. In this paper, by using the total decay width $\Gamma(H\to\gamma\gamma)$ which has been calculated up to N$^4$LO QCD corrections, we derive its PMC series by using the PMC single-scale setting approach and estimate its unknown N$^5$LO contributions by using the Bayesian analysis. The Bayesian-based approach estimates the magnitude of the UHO contributions based on an optimized analysis of probability density distribution, and the predicted UHO contribution becomes more accurate when more loop terms have been known to tame the probability density function. Using the top-quark pole mass $M_t$=172.69 GeV and the Higgs mass $M_H$=125.25 GeV as inputs, we obtain $\Gamma(H\to\gamma\gamma) =9.56504~{\rm keV}$ and the estimated N$^5$LO contribution to the total decay width is $\Delta\Gamma_H=\pm1.65\times10^{-4}~{\rm keV}$ for the smallest credible interval of $95.5\%$ degree-of-belief.

hep-ph↗