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Title: Robust extraction of the proton charge radius from electron-proton scattering data

Abstract

Background: Extracting the proton charge radius from electron scattering data requires determining the slope of the charge form factor at Q 2 15 of zero. But as experimental data never reach that limit, numerous methods for making the extraction have been proposed, though often the functions are determined after seeing the data which can lead to confirmation bias. Purpose: To find functional forms that will allow for a robust extraction of the input radius for a wide variety of functional forms in order to have confidence in the extraction from upcoming low Q 2 experimental data such as the Jefferson Lab PRad experiment. Method: We create a general framework for inputting form-factor functions as well as various fitting functions. The input form factors are used to generate pseudo-data with fluctuations intended to mimic the binning and random uncertainty of a given set of real data. All combinations of input functions and fit functions can then be tested repeatedly against regenerated pseudo-data. Since the input radius is known, this allows us to find those functions that are robust for radius extractions in an objective fashion. Results: For the range and uncertainty of the PRad data, we find that a two-parameter rationalmore » function, a two-parameter continued fraction and the second order polynomial expansion of z can extract the input radius regardless of the input charge form factor function that is used. Conclusions: We have created an easily expandable framework to search for functional forms that allow for a robust extraction of the radius from a given binning and uncertainty of pseudo-data generated from a wide variety of trial functions. This method has enabled a successful search for the best functional forms to extract the radius from the upcoming PRad data, and can be used for other experiments.« less

Authors:
 [1];  [2];  [3];  [4];  [5];  [6];  [7];  [2];  [1];  [1]
  1. Duke Univ., Durham, NC (United States); triangle Univ. Nuclear Lab., Durham, NC (United States)
  2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
  3. Mississippi State Univ., Mississippi State, MS (United States)
  4. Duke Univ., Durham, NC (United States); triangle Univ. Nuclear Lab., Durham, NC (United States); Duke Kunchan Univ., Jiangsu (China)
  5. North Carolina A & T State Univ., Greensboro, NC (United States)
  6. Idaho State Univ., Pocatello, ID (United States)
  7. Univ. of Virginia, Charlottesville, VA (United States)
Publication Date:
Research Org.:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Mississippi State Univ., Mississippi State, MS (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP)
OSTI Identifier:
1466730
Alternate Identifier(s):
OSTI ID: 1465610; OSTI ID: 1599330
Report Number(s):
JLAB-PHY-18-2655; DOE/OR/23177-4361; arXiv:1803.01629
Journal ID: ISSN 2469-9985; PRVCAN
Grant/Contract Number:  
AC05-060R23177; FG02-03ER41231; FG02-07ER41528
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review C
Additional Journal Information:
Journal Volume: 98; Journal Issue: 2; Journal ID: ISSN 2469-9985
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Yan, Xuefei, Higinbotham, Douglas W., Dutta, Dipangkar, Gao, Haiyan, Gasparian, Ashot, Khandaker, Mahbub A., Liyanage, Nilanga, Pasyuk, Eugene, Peng, Chao, and Xiong, Weizhi. Robust extraction of the proton charge radius from electron-proton scattering data. United States: N. p., 2018. Web. doi:10.1103/PhysRevC.98.025204.
Yan, Xuefei, Higinbotham, Douglas W., Dutta, Dipangkar, Gao, Haiyan, Gasparian, Ashot, Khandaker, Mahbub A., Liyanage, Nilanga, Pasyuk, Eugene, Peng, Chao, & Xiong, Weizhi. Robust extraction of the proton charge radius from electron-proton scattering data. United States. doi:10.1103/PhysRevC.98.025204.
Yan, Xuefei, Higinbotham, Douglas W., Dutta, Dipangkar, Gao, Haiyan, Gasparian, Ashot, Khandaker, Mahbub A., Liyanage, Nilanga, Pasyuk, Eugene, Peng, Chao, and Xiong, Weizhi. Tue . "Robust extraction of the proton charge radius from electron-proton scattering data". United States. doi:10.1103/PhysRevC.98.025204. https://www.osti.gov/servlets/purl/1466730.
@article{osti_1466730,
title = {Robust extraction of the proton charge radius from electron-proton scattering data},
author = {Yan, Xuefei and Higinbotham, Douglas W. and Dutta, Dipangkar and Gao, Haiyan and Gasparian, Ashot and Khandaker, Mahbub A. and Liyanage, Nilanga and Pasyuk, Eugene and Peng, Chao and Xiong, Weizhi},
abstractNote = {Background: Extracting the proton charge radius from electron scattering data requires determining the slope of the charge form factor at Q2 15 of zero. But as experimental data never reach that limit, numerous methods for making the extraction have been proposed, though often the functions are determined after seeing the data which can lead to confirmation bias. Purpose: To find functional forms that will allow for a robust extraction of the input radius for a wide variety of functional forms in order to have confidence in the extraction from upcoming low Q2 experimental data such as the Jefferson Lab PRad experiment. Method: We create a general framework for inputting form-factor functions as well as various fitting functions. The input form factors are used to generate pseudo-data with fluctuations intended to mimic the binning and random uncertainty of a given set of real data. All combinations of input functions and fit functions can then be tested repeatedly against regenerated pseudo-data. Since the input radius is known, this allows us to find those functions that are robust for radius extractions in an objective fashion. Results: For the range and uncertainty of the PRad data, we find that a two-parameter rational function, a two-parameter continued fraction and the second order polynomial expansion of z can extract the input radius regardless of the input charge form factor function that is used. Conclusions: We have created an easily expandable framework to search for functional forms that allow for a robust extraction of the radius from a given binning and uncertainty of pseudo-data generated from a wide variety of trial functions. This method has enabled a successful search for the best functional forms to extract the radius from the upcoming PRad data, and can be used for other experiments.},
doi = {10.1103/PhysRevC.98.025204},
journal = {Physical Review C},
issn = {2469-9985},
number = 2,
volume = 98,
place = {United States},
year = {2018},
month = {8}
}

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Works referenced in this record:

Theoretical constraints and systematic effects in the determination of the proton form factors
journal, January 2015


Consistency of electron scattering data with a small proton radius
journal, June 2016


Evaluation of the strength of electron-proton scattering data for determining the proton charge radius
journal, January 2016


First measurement of proton's charge form factor at very low Q2 with initial state radiation
journal, August 2017


Extraction of the proton radius from electron-proton scattering data
journal, July 2015


Muonic Hydrogen and the Proton Radius Puzzle
journal, October 2013


The Rydberg constant and proton size from atomic hydrogen
journal, October 2017


Nucleon form factors in dispersively improved chiral effective field theory: Scalar form factor
journal, November 2017


Electric and magnetic form factors of the proton
journal, July 2014


Realistic transverse images of the proton charge and magnetization densities
journal, January 2011


Accurate nucleon electromagnetic form factors from dispersively improved chiral effective field theory
journal, September 2018


Proton and neutron electromagnetic form factors and uncertainties
journal, February 2018


Bootstrap Methods: Another Look at the Jackknife
journal, January 1979


Nucleon form factors in dispersively improved chiral effective field theory. II. Electromagnetic form factors
journal, May 2018


Polarization transfer observables in elastic electron-proton scattering at Q 2 = 2.5 , 5.2, 6.8, and 8.5   GeV 2
journal, November 2017


High-Precision Determination of the Electric and Magnetic Form Factors of the Proton
journal, December 2010


Better Bootstrap Confidence Intervals
journal, March 1987


Review of experimental and theoretical status of the proton radius puzzle
journal, January 2017


Proton radius from electron scattering data
journal, May 2016


Proton Structure from the Measurement of 2S-2P Transition Frequencies of Muonic Hydrogen
journal, January 2013


The size of the proton
journal, July 2010

  • Pohl, Randolf; Antognini, Aldo; Nez, François
  • Nature, Vol. 466, Issue 7303
  • DOI: 10.1038/nature09250

The proton radius puzzle
journal, May 2015


On the determination of the proton RMS-radius from electron scattering data
journal, March 1975

  • Borkowski, F.; Simon, G. G.; Walther, V. H.
  • Zeitschrift f�r Physik A: Atoms and Nuclei, Vol. 275, Issue 1
  • DOI: 10.1007/BF01409496

Dispersion analysis of the nucleon form factors including meson continua
journal, March 2007


ROOT — An object oriented data analysis framework
journal, April 1997

  • Brun, Rene; Rademakers, Fons
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 389, Issue 1-2
  • DOI: 10.1016/S0168-9002(97)00048-X

Proton charge and magnetic rms radii from the elastic ep scattering data
journal, October 2010


Proton radius from electron-proton scattering and chiral perturbation theory
journal, March 2017


Reexamination of proton rms radii from low- q power expansions
journal, January 2017


The size of the proton: Closing in on the radius puzzle
journal, November 2012

  • Lorenz, I. T.; Hammer, H. -W.; Meißner, Ulf-G.
  • The European Physical Journal A, Vol. 48, Issue 11
  • DOI: 10.1140/epja/i2012-12151-1

Polynomial fits and the proton radius puzzle
journal, October 2014


Reduction of the proton radius discrepancy by 3 σ
journal, October 2014


Proton Charge Radius (PRad) Experiment at Jefferson Lab
journal, January 2016


Proton Charge Radius from Electron Scattering
journal, December 2017


Minuit - a system for function minimization and analysis of the parameter errors and correlations
journal, December 1975


CODATA recommended values of the fundamental physical constants: 2014
journal, September 2016


Proton radius from Bayesian inference
journal, November 2014


Simple parametrization of nucleon form factors
journal, December 2004


Implications of the discrepancy between proton form factor measurements
journal, February 2004


To Explain or to Predict?
journal, August 2010


On the rms-radius of the proton
journal, December 2003


The PRad experiment and the proton radius puzzle
journal, January 2014


New Measurement of the 1 S 3 S Transition Frequency of Hydrogen: Contribution to the Proton Charge Radius Puzzle
journal, May 2018


Evaluation of the Proton Charge Radius from Electron–Proton Scattering
journal, September 2015

  • Arrington, John; Sick, Ingo
  • Journal of Physical and Chemical Reference Data, Vol. 44, Issue 3
  • DOI: 10.1063/1.4921430