CLAS Physics Database

JLab | Search | Overview | Login | Edit | Register

Measurement E179M4

You are not logged in.

Experiment: SIDIS Dihadron Beam Spin Asymmetry, 2020

Spokespersons: C. Dilks, T. Hayward, A. Vossen

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.

Measurement comment: Binning scheme: bins of PT, for Mh below and above 0.63 GeV

Publication:

Quantity measured: ALUsin φh,
Beam-spin asymmetry moment, where φh is the azimuthal angle between the leptonic and the hadronic planes.
Beam: e, polarization: longitudinal
Target: p (Z=1, A=1), polarization: none
Final state: π π + X, polarization: none

Q2 : 1 — 10.6 GeV2
W : 2 — 4 GeV
xb : 0.06 — 0.77
Ebeam : 10.6041 GeV

Sorry, picture is not available

Click here to get data in text file, delimited with tabs.

Measured data:

Q2,
GeV2
x M(π+),
GeV
z PT,
GeV
ALUsin φh Data errors Systematic errors
3.534 0.309 0.501 0.591 0.169 0.00768601 0.0111222 0.000895647115342886
3.429 0.284 0.493 0.568 0.311 0.00604663 0.0107443 0.000935293407502079
3.221 0.259 0.481 0.553 0.426 0.0184025 0.00894344 0.00145967217822139
3.123 0.244 0.474 0.541 0.533 0.0410272 0.00751662 0.00331464405255088
3.027 0.231 0.464 0.532 0.653 0.0364317 0.00562838 0.00226386168017625
2.759 0.204 0.454 0.531 0.864 0.0294944 0.00409833 0.00184378385449412
2.897 0.226 0.946 0.56 0.16 0.00152296 0.00520304 0.000482781986708829
2.865 0.221 0.915 0.566 0.306 0.00134668 0.00575449 0.00114337573477946
2.837 0.217 0.894 0.57 0.422 0.0222453 0.00564458 0.00202705775736068
2.752 0.207 0.876 0.57 0.53 0.024928 0.0080132 0.0016535409860614
2.677 0.199 0.858 0.574 0.648 0.040103 0.00937557 0.00277947659424996
2.528 0.182 0.832 0.586 0.852 0.0277259 0.0112356 0.00189258745978502