CLAS Physics Database

Measurement E179M12

Experiment: SIDIS Dihadron Beam Spin Asymmetry
Year: 2020

Measurement comment:

Binning scheme: bins of PT, 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 φR
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 φR uncertainty syst. uncert.
3.534 0.309 0.501 0.591 0.169 0.0133766 0.00879979 0.00115379946291313
3.429 0.284 0.493 0.568 0.311 -0.00303935 0.0118928 0.00125842779899126
3.221 0.259 0.481 0.553 0.426 -0.00986439 0.0109266 0.0015085871960776
3.123 0.244 0.474 0.541 0.533 0.00802265 0.00955648 0.00102183016462944
3.027 0.231 0.464 0.532 0.653 0.0219307 0.00728617 0.00196583962774478
2.759 0.204 0.454 0.531 0.864 0.00282931 0.00522646 0.00120200035850002
2.897 0.226 0.946 0.56 0.16 0.0485798 0.00389608 0.00262536948187235
2.865 0.221 0.915 0.566 0.306 0.0472761 0.0048068 0.00251653448171013
2.837 0.217 0.894 0.57 0.422 0.0477243 0.00561657 0.00250941655603733
2.752 0.207 0.876 0.57 0.53 0.0329534 0.00759774 0.00179442566868185
2.677 0.199 0.858 0.574 0.648 0.0275174 0.00801882 0.00131337765943696
2.528 0.182 0.832 0.586 0.852 -0.000473721 0.010403 0.00173243292217394