This file is http://www.columbia.edu/~seligman/ccfr/results/READ_ME The sub-directory pub/ccfr/results contains the final results from the CCFR structure-function analysis. The results are given in the form of plain ASCII text files. Since this analysis has eighteen sources of systematic error for each structure function and each (x,Q2) point, the systematic errors have been broken up into separate files as described below. THE SYSTEMATIC ERRORS IN THESE FILES MUST NOT BE ADDED IN QUADRATURE. It's simply not possible to add our statistical and systematic errors in quadrature and have a meaningful result. If you're going to do an analysis on our results that includes our systematic errors, you _must_ either: 1) Repeat your analysis eighteen times, once for each of our systematic variations, and add the variations of your analysis results in quadrature; or 2) Do a global systematic fit by incorporating our systematic variations into a Chi**2. For more information about the systematic errors and the QCD fits, see William Seligman's Ph.D. thesis, Nevis Reports 292, Chapter 7 and Appendix D. For a brief description of each systematic quantity, see the file SYSTEMATICS. If you want a start on how to calculate a Chi**2 with our systematic errors, check out ccfr/source/qcdlib/, especially routines datscn.f and chicalc.f. Whenever these data are used, the following reference must be included: W. Seligman et al. (CCFR Collaboration), hep-ex/9701017, Phys. Rev. Lett. 79: 1213 (1997); W. Seligman, Ph.D. Thesis (Columbia University), Nevis Report 292. FINAL RESULTS AND STATISTICAL ERRORS ------------------------------------ staterr.table Contains the values of F2, xF3, and their statistical errors. These are the "final results" from the CCFR structure function analysis. The contents of this file _must_ be considered in context with the systematic error files described below. f2-xf3-staterr.table Contains the values of (F2 - xF3) and the associated statistical errors, with the correlated error taken into account. These data are provided because they are directly related to the anti-quark content of the proton. SYSTEMATIC ERRORS ----------------- f2-caliberr.table xf3-caliberr.table Contains the systematic errors in F2 (xF3) from quantities related to the energy calibration: the hadron energy calibration (experiments E744 and E770 are varied separately), the hadron energy offset, the muon energy calibration, and the muon energy offset. f2-fluxerr.table xf3-fluxerr.table Contains the systematic errors in F2 (xF3) from B/A, a quantity determined in the flux extraction. The values of B/A for neutrinos and anti-neutrinos, and for experiments E744 and E770, are varied separately. f2-xsecerr.table xf3-xsecerr.table Contains the systematic errors in F2 (xF3) from quantities related to the total neutrino-iron cross-section: the overall normalization (Sigma), the ratio of the anti-neutrino to neutrino cross-section (Sig Rat), the effect of _not_ adjusting the flux for a linear cross-section (No Smooth), and R. (OK, R doesn't relate directly to the total cross-section, but there wasn't room in the following file...) f2-modelerr.table xf3-modelerr.table Contains the systematic errors in F2 (xF3) from quantities related to the cross-section model: the strange sea shape (Alpha), the branching ratio for charm production (Charm Br), the mass of the charm quark, the normalization of the strange sea (Kappa), and variation in Buras-Gaemers physics model. Note this file is _not_ the same as "model-corr" (see below). SEPARATE EXPERIMENTS -------------------- staterr-744.table staterr-770.table Contains the value of F2, xF3, and their statistical errors from the separate extraction of SF from experiments E744 and E770. f2-systerr-e744.table f2-systerr-e770.table xf3-systerr-e744.table xf3-systerr-e770.table Contains the systematic errors for F2 (xF3) for those systematic quantities that are independent for each experiment: the hadron energy calibration (Had Cal), and the value of B/A for neutrinos and anti-neutrinos from the flux extraction. READING THE FILES ----------------- Apart from the first two lines of each file, the contents of each line in the file can be read by the FORTRAN statements: write(iuunit,340) x,q2,f,err_f, ... 340 format(f6.4,f6.1,10(1x,g12.4)) OTHER USEFUL FILES ------------------ f2-model-corr.table xf3-model-corr.table These tables contain the results of extracting the structure functions without one or more of the model corrections. The corrections are given in the form: F(without correction) / F(with correction) So, for example, the Cmass column contains the ratio of: F(without charm) / F(charm) (The charm mass enters into the structure-function extraction via the slow-rescaling correction; eliminating the charm mass therefore eliminates that correction). The corrections included in the table are the isoscalar correction, the Bardin radiative correction, the slow-rescaling correction, and the propagator correction (due to the mass of the W-boson). The tables include an "All" column which represent the effect of removing all four model corrections. These tables are provided for the benefit of the people who have requested our structure functions extracted without a given correction (for example, we have received requests for our SF extracted without the isoscalar correction). To remove a model correction from the SF, multiply the value from staterr.table by the appropriate column from the "model-corr" table. For example, to get F2 without the Bardin radiative correction, compute: F2 (w/o radiative correction) = F2 (from staterr.table) * Rad (from f2-model-corr.table) IMPORTANT: The model-correction tables are different from the systematic-error tables. The systematic error tables represent the _additive_ shift in the structure functions due to a one sigma variation in the error of a quantity. The correction tables represent the _multiplicative_ shift in the structure functions due to entirely removing one portion of our physical model. See W. Seligman Thesis, Appendix D, for more information. xf3-sea-corr.table gives the ratio: xF3 (no s-c correction) / xF3 (with s-c correction) There is a separate correction listed for neutrinos and anti-neutrinos. In theory, if you multiply the published xF3 by the columns in this table, you'll get xF3(neutrino) and xF3(anti-neutrino) separately. In practice, what you'll get is the strange sea as measured in the leading-order CCFR dimuon analysis. (Yes, the negative numbers in the anti-neutrino ratio are correct: at low x and low Q2 xF3(anti-neutrino) is negative.) for-plots-only.txt This file contains the CCFR structure functions with the statistical and systematic errors added in quadrature. The contents of this file can be used for only one purpose: to make plots. To perform any analysis that incorporates the CCFR systematic errors, see the instructions at the top of this READ_ME file.