Search arXivSearch

arXiv · hep-ph/9710316

Analytic Perturbation Theory: A New Approach to the Analytic Continuation of the Strong Coupling Constant $α_S$ into the Timelike Region

Abstract

The renormalization group applied to perturbation theory is ordinarily used to define the running coupling constant in the spacelike region. However, to describe processes with timelike momenta transfers, it is important to have a self-consistent determination of the running coupling constant in the timelike region. The technique called analytic perturbation theory (APT) allows a consistent determination of this running coupling constant. The results are found to disagree significantly with those obtained in the standard perturbative approach. Comparison between the standard approach and APT is carried out to two loops, and threshold matching in APT is applied in the timelike region.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Kimball A. Milton, Olga P. Solovtsova. 1997-10-10. Analytic Perturbation Theory: A New Approach to the Analytic Continuation of the Strong Coupling Constant $α_S$ into the Timelike Region. https://doi.org/10.1103/physrevd.57.5402

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Exploring the Singlino-dominated Thermal Neutralino Dark Matter in the $Z_3$ invariant NMSSM

We examine the parameter space of the Next to Minimal Supersymmetric Standard Model (NMSSM) with Singlino-dominated neutralino $\widetildeχ_1^0$ as the lightest supersymmetric particle (LSP). Our study focuses on identifying the regions within this parameter space that produce a thermal relic abundance of $\widetildeχ_1^0$ smaller than the observed cold dark matter relic density while remaining consistent with constraints from LEP measurements, low-energy experiments, Higgs measurements, LHC data, and dark matter direct detection experiments. We identify the dominant annihilation modes of the LSP neutralino across varying LSP mass ranges $\sim \mathcal{O}(1)-\mathcal{O}(10^{3})~$GeV. Furthermore, we conduct a benchmark study to assess the production rates of triple-boson final states emerging from direct electroweakino pair production at the LHC. Drawing insights from these findings, we perform a detailed collider analysis to explore the future potential of probing the triple-boson final states involving a light Higgs boson at the high-luminosity LHC (HL-LHC).

hep-ph

Unveiling the Collins-Soper kernel in inclusive DIS at threshold

We revisit the factorization of inclusive deep inelastic scattering (DIS) near the kinematic threshold in terms of collinear, off-light-cone operators. At threshold, particle production develops around two opposite near-light-cone directions in close analogy with transverse-momentum-dependent semi-inclusive DIS. The Collins-Soper kernel then emerges as the universal function governing the rapidity evolution of the relevant parton correlators in both cases. Our new framework also clarifies outstanding issues related to soft radiation and rapidity divergences at threshold.

hep-ph

Novel Light Dark Matter Detection with Quantum Parity Detector Using Qubit Arrays

We present the design and the sensitivity reach of the Qubit-based Light Dark Matter detection experiment. We propose the novel two-chip design to reduce signal dissipation, with quantum parity measurement to enhance single-phonon detection sensitivity. We demonstrate the performance of the detector with full phonon and quasiparticle simulations. The experiment is projected to detect $\gtrsim 30$ meV energy deposition with nearly $100\%$ efficiency and high energy resolution. The sensitivity to $m_χ\gtrsim 0.01$ MeV dark matter scattering cross section is expected to be advanced by orders of magnitude for both light and heavy mediators, and similar improvements will be achieved for axion and dark photon absorption in the $0.04$-$0.2$ eV mass range.

hep-ph