Kinematic names (d2n)

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The standard kinematic names used in the run database are constructed according to a few simple rules:

  • If the name begins with the letters pos, the LHRS is set to a positive polarity. Otherwise, the polarity is assumed to be negative.
  • If the next character is the number 4, the beam energy is 4.7 GeV (that is, the standard 4-pass beam energy). Otherwise, the beam energy is assumed to be 5.9 GeV (5-pass).
  • The next character is a capital letter (e.g. A) which indicates the momentum setting of the LHRS. The table of momentum settings is below. Unfortunately, the mapping from letter to momentum setting is not the same for 4-pass and 5-pass. Some gaps exist because accelerator problems meant that some kinematics were skipped entirely.
  • Finally, the digits that follow the capital letter (e.g. 0, 90, 270) indicate the spin orientation of the target. 0 degrees corresponds to longitudinal polarization; 90 and 270 are transverse.
Kinematic Code LHRS Momentum (GeV/c)
A 0.6
4A 0.6
B 0.7
4C 0.8
D 0.9
4E 1.12
F 1.13
4F 1.19
G 1.2
4G 1.26
H 1.27
4H 1.34
I 1.34
4I 1.42
J 1.42
4J 1.51
K 1.51
4K 1.6
L 1.6
M 1.7