19–21 Aug 2025
Universitas Gadjah Mada
Asia/Jakarta timezone

Extraction of Proton Electric Form Factor and Radius from Low-$Q^2$ Data

20 Aug 2025, 09:20
25m
Department of Physics (Universitas Gadjah Mada)

Department of Physics

Universitas Gadjah Mada

Speaker

Jingle Magallanes (Mindanao State University - Iligan Institute of Technology)

Description

This study calculates the energy decay rates ($r$) for both up and down quarks and the electric form factors ($G_E$) of the proton using low four-momentum transfer ($Q^2$) data from the PRad and MaMi electron-proton scattering experiments. The extracted decay rates for u and d quarks were nearly identical with $r≈3.94$, demonstrating a consistent exponential decay behavior across increasing $Q^2$. Moreover, analysis of the electric form factor confirmed that the calculated values closely match with PRad and MaMi data at low $Q^2$, validating the model in this region. However, increasing residuals and deviations from both MaMi data and the standard dipole form factor assumption at higher $Q^2$ indicate the model’s limitations. The results underscore the sensitivity of both decay rates and $G_E$ to the momentum transfer range and the need for a refined theoretical framework that incorporates higher-order QED corrections and spin-spin interactions. The extracted average proton charge radius is $0.8291 ±0.0019(stat) ±0.0004(std) fm$, aligns closely with PRad results, supporting evidence for a smaller proton radius.

Author

Mr Roland Lumpay (Caraga State University)

Co-authors

Mr Gerome Paterez (Caraga State University) Mr Jade Jusoy (Caraga State University) Jingle Magallanes (Mindanao State University - Iligan Institute of Technology)

Presentation materials

There are no materials yet.