CLAS Physics Database

Measurement E179M23

Experiment: SIDIS Dihadron Beam Spin Asymmetry
Year: 2020

Measurement comment:

Binning scheme: bins of z, for Mh below and above 0.63 GeV

Experiment comment:


Process: ep→eπ+π-X
Data tables have the following columns:
  1. mean Q2
  2. mean x
  3. mean Mh, the dihadron invariant mass
  4. mean z, of the pion pair
  5. mean PT, more commonly written Ph, is the component of the total dihadron momentum, transverse to q
  6. ALU amplitude, for a particular modulation
  7. statistical uncertainty
  8. systematic uncertainty
For each of the 7 asymmetry modulations, there are 4 tables, one for each binning scheme: (1) binned by x, (2) binned by Mh, (3) binned by z and Mh, and (4) binned by PT and Mh.
Spokespersons: C. Dilks, T. Hayward, A. Vossen
Reaction: ep → π π + X
Polarization: beam (longitudinal)
Quantity: ALUsin (−φh+2φR)
Q2: 1.0 — 10.6 GeV2
W: 2.0 — 4.0 GeV
x: 0.06 — 0.77
Ebeam: 10.6041 GeV
Publication:
T.B. Hayward, C. Dilks, A. Vossen, H. Avakian Observation of Beam Spin Asymmetries in the Process ep→eπ+π-X with CLAS12 // (submitted to PRL)

Measurement data
Q2, [GeV2] x M(π+), [GeV] z PT, [GeV] ALUsin (−φh+2φR) uncertainty syst. uncert.
3.129 0.22 0.464 0.4 0.598 0.0112874 0.00660137 0.00132443256354091
3.21 0.244 0.468 0.474 0.61 -0.000533796 0.00685607 0.000526779987874587
3.131 0.248 0.472 0.528 0.608 0.00127454 0.0064317 0.000699477978967493
3.107 0.254 0.47 0.579 0.59 -0.00246362 0.00688905 0.00158508342839829
3.021 0.253 0.478 0.638 0.556 0.00805179 0.00640232 0.00119632464972421
2.825 0.234 0.482 0.727 0.5 0.0150553 0.00746905 0.00166767103349953
2.764 0.192 0.821 0.404 0.386 -0.0244509 0.00577767 0.0007362834358267
2.847 0.209 0.859 0.474 0.427 -0.0186648 0.00553041 0.00136146518172065
2.862 0.218 0.88 0.528 0.451 -0.0282167 0.00452298 0.00103424171674529
2.85 0.223 0.9 0.58 0.466 -0.0292047 0.00544723 0.0011793807081504
2.785 0.221 0.921 0.638 0.467 -0.0228124 0.00501054 0.001301136465257
2.628 0.202 0.958 0.731 0.438 -0.0291538 0.00512626 0.00152798130881471