سمینار هفتگی
گروه فیزیک انرژی های بالا
کاوش ساختار نوکلئون با بکارگیری اثرات پیچشهای بالاتر در توزیعهای پارتونی قطبیده
سخنران: H. Abdolmaleki, School of Physics
29 مرداد 1404
14:00 تا 15:00
Date and time
Tuesday, August 19, 2025 (28 Mordad), 2:00 pm (Tehran time)
Link
https://www.skyroom.online/ch/schoolofphysics/highenergyseminar
Abstract
Parton Distribution Functions (PDFs) are key to understanding the momentum and spin distributions of fundamental particles inside the nucleon, and their precise determination is crucial for rigorous tests of the Standard Model and for predicting outcomes in high-energy collider experiments. In this study, we employ Gegenbauer polynomials—a set of orthogonal polynomials with strong convergence properties and superior ability to model the detailed shape of distributions—to parameterize the polarized parton distribution functions (PPDFs). These polynomials are defined by two key parameters, and by fitting experimental data, unknown parameters are extracted that provide deeper insights into the proton’s structure.
By analyzing comprehensive datasets, especially the final JLAB CLAS/EG1b data for proton and deuteron, the essential role of higher twist effects in accurately determining the PPDFs is demonstrated. The polarized structure functions of the proton, neutron, and deuteron are studied at NLO accuracy, both with and without considering higher twist effects. Additionally, the polarized Bjorken sum rule and proton helicity sum rule are examined to validate the fitting results. The findings show strong agreement with existing data and various parameterization models, indicating that this approach effectively decodes the complex structure of the nucleon and opens new horizons in understanding the behavior of fundamental particles at high energies.
Link: https://www.skyroom.online/ch/schoolofphysics/highenergyseminar
گروه فیزیک انرژی های بالا
کاوش ساختار نوکلئون با بکارگیری اثرات پیچشهای بالاتر در توزیعهای پارتونی قطبیده
سخنران: H. Abdolmaleki, School of Physics
29 مرداد 1404
14:00 تا 15:00
Date and time
Tuesday, August 19, 2025 (28 Mordad), 2:00 pm (Tehran time)
Link
https://www.skyroom.online/ch/schoolofphysics/highenergyseminar
Abstract
Parton Distribution Functions (PDFs) are key to understanding the momentum and spin distributions of fundamental particles inside the nucleon, and their precise determination is crucial for rigorous tests of the Standard Model and for predicting outcomes in high-energy collider experiments. In this study, we employ Gegenbauer polynomials—a set of orthogonal polynomials with strong convergence properties and superior ability to model the detailed shape of distributions—to parameterize the polarized parton distribution functions (PPDFs). These polynomials are defined by two key parameters, and by fitting experimental data, unknown parameters are extracted that provide deeper insights into the proton’s structure.
By analyzing comprehensive datasets, especially the final JLAB CLAS/EG1b data for proton and deuteron, the essential role of higher twist effects in accurately determining the PPDFs is demonstrated. The polarized structure functions of the proton, neutron, and deuteron are studied at NLO accuracy, both with and without considering higher twist effects. Additionally, the polarized Bjorken sum rule and proton helicity sum rule are examined to validate the fitting results. The findings show strong agreement with existing data and various parameterization models, indicating that this approach effectively decodes the complex structure of the nucleon and opens new horizons in understanding the behavior of fundamental particles at high energies.
Link: https://www.skyroom.online/ch/schoolofphysics/highenergyseminar
