SIG_____________________________integrated cross section
 SIG is the observable name for a cross section.
 On its own it signifies a total or integrated
 cross section. In combinations with D, or D2 etc.
 it is used in the differential cross section
 as shown below.
SIG/SIG, RATIO, N/N_____________ratio of cross sections/distributions
 These are used to signify the measurement is 
 of a ratio of cross sections or other equvalent
 distributions.
DSIG/Dxname_____________________single differential cross section
D2SIG/Dxname1/Dxname2___________double differential cross section
D3SIG/Dxname1/Dxname2/Dxname3___triple differential cross section
E*D3SIG/DP**3___________________invariant cross section
N_______________________________number of events
DN/Dxname_______________________single differential distribution
D2N/Dxname1/Dxname2_____________double differential distribution
D3N/Dxname1/Dxname2/Dxname3_____triple differential cross distribution
POL, POL.POL, POL.POL.POL_______single, double and triple spin polarisations
ASYM____________________________asymmetry measurement
F2, XF3, FL_____________________structure functions
MULT, DISPERSION, MULT2 etc..___multiplicity measurements
A1, A2, G1, G2__________________spin asymmetries and structure functions
V1, V2,... V11, V22.. etc...____azimuthal asymmetries
ACC, EFF________________________acceptance, efficiency
CORR, RCORR_____________________correlation
RHO_____________________________density matrix element
SLOPE, POWER____________________exponential slope/power of a fit
ALPHAS, SIN2TW__________________alpha-s, sin^2(theta-w)
FORMFACTOR______________________Form Factor
RAA, RPA, RPP___________________nuclear modification factor
LEG, LEGN, LEGP, LEGPN__________Legendre Coefficients
  Somewhat historical!
  Legendre coefficients of fit to the DSIG/DOMEGA distributions
  LEGN is normalised
  LEGP is for  P*DSIG/DOMEGA
YLM_____________________________Ylm moment
AMP, PHASE______________________amplitude, phase