Partonic structure of neutral pseudoscalars via two photon transition form factors
Abstract
Here, the γγ* → η _{c,b} transition form factors are computed using a continuum approach to the two valencebody boundstate problem in relativistic quantum field theory, and thereby unified with equivalent calculations of electromagnetic pion elastic and transition form factors. The resulting γγ* → η _{c} form factor, G _{ηc}(Q ^{2}), is consistent with available data; significantly, at accessible momentum transfers, Q ^{2}G _{ηc}(Q ^{2}) lies well below its conformal limit. These observations confirm that the leadingtwist parton distribution amplitudes of heavyheavy bound states are compressed relative to the conformal limit. A clear understanding of the distribution of valence quarks within mesons thus emerges, a picture which connects Goldstone modes, built from the lightest quarks in nature, with systems containing the heaviest valence quarks that can now be studied experimentally, and highlights basic facts about manifestations of mass within the Standard Model.
 Authors:
 Publication Date:
 Research Org.:
 Argonne National Lab. (ANL), Argonne, IL (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), Nuclear Physics (NP) (SC26)
 OSTI Identifier:
 1374604
 Alternate Identifier(s):
 OSTI ID: 1351044
 Grant/Contract Number:
 AC0206CH11357
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physical Review D
 Additional Journal Information:
 Journal Volume: 95; Journal Issue: 7; Journal ID: ISSN 24700010
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Citation Formats
Raya, Khepani, Ding, Minghui, Bashir, Adnan, Chang, Lei, and Roberts, Craig D. Partonic structure of neutral pseudoscalars via two photon transition form factors. United States: N. p., 2017.
Web. doi:10.1103/PhysRevD.95.074014.
Raya, Khepani, Ding, Minghui, Bashir, Adnan, Chang, Lei, & Roberts, Craig D. Partonic structure of neutral pseudoscalars via two photon transition form factors. United States. doi:10.1103/PhysRevD.95.074014.
Raya, Khepani, Ding, Minghui, Bashir, Adnan, Chang, Lei, and Roberts, Craig D. Mon .
"Partonic structure of neutral pseudoscalars via two photon transition form factors". United States.
doi:10.1103/PhysRevD.95.074014. https://www.osti.gov/servlets/purl/1374604.
@article{osti_1374604,
title = {Partonic structure of neutral pseudoscalars via two photon transition form factors},
author = {Raya, Khepani and Ding, Minghui and Bashir, Adnan and Chang, Lei and Roberts, Craig D.},
abstractNote = {Here, the γγ* → ηc,b transition form factors are computed using a continuum approach to the two valencebody boundstate problem in relativistic quantum field theory, and thereby unified with equivalent calculations of electromagnetic pion elastic and transition form factors. The resulting γγ* → ηc form factor, Gηc(Q2), is consistent with available data; significantly, at accessible momentum transfers, Q2Gηc(Q2) lies well below its conformal limit. These observations confirm that the leadingtwist parton distribution amplitudes of heavyheavy bound states are compressed relative to the conformal limit. A clear understanding of the distribution of valence quarks within mesons thus emerges, a picture which connects Goldstone modes, built from the lightest quarks in nature, with systems containing the heaviest valence quarks that can now be studied experimentally, and highlights basic facts about manifestations of mass within the Standard Model.},
doi = {10.1103/PhysRevD.95.074014},
journal = {Physical Review D},
number = 7,
volume = 95,
place = {United States},
year = {Mon Apr 10 00:00:00 EDT 2017},
month = {Mon Apr 10 00:00:00 EDT 2017}
}
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