39 research outputs found
Measurement of the proton and deuteron structure functions, F2p and F2d, and of the ratio sigma(L)/sigma(T)
The muon-proton and muon-deuteron inclusive deep inelastic scattering cross
sections were measured in the kinematic range 0.002 < x < 0.60 and 0.5 < Q2 <
75 GeV2 at incident muon energies of 90, 120, 200 and 280 GeV. These results
are based on the full data set collected by the New Muon Collaboration,
including the data taken with a small angle trigger. The extracted values of
the structure functions F2p and F2d are in good agreement with those from other
experiments. The data cover a sufficient range of y to allow the determination
of the ratio of the longitudinally to transversely polarised virtual photon
absorption cross sections, R= sigma(L)/sigma(T), for 0.002 < x < 0.12 . The
values of R are compatible with a perturbative QCD prediction; they agree with
earlier measurements and extend to smaller x.Comment: In this replacement the erroneously quoted R values in tables 3-6 for
x>0.12, and R1990 values in tables 5-6 for all x, have been corrected, and
the cross sections in tables 3-4 have been adapted. Everything else,
including the structure functions F2, remained unchanged. 22 pages, LateX,
including figures, with two .sty files, and three separate f2tab.tex files
for the F2-tables. Accepted for publication in Nucl.Phys.B 199
Measurement of the proton and the deuteron structure functions F2p and F2d
The proton and deuteron structure functions F2p and F2d were measured in the
kinematic range 0.006<x<0.6 and 0.5<Q^2<75 GeV^2, by inclusive deep inelastic
muon scattering at 90, 120, 200 and 280 GeV. The measurements are in good
agreement with earlier high precision results. The present and earlier results
together have been parametrised to give descriptions of the proton and deuteron
structure functions F2 and their uncertainties over the range 0.006<x<0.9.Comment: 22 pages, using LATEX, 12pt, epsfig.sty, rotating.sty; 2 tables and 6
figures uuencoded compressed tar files in f2fig.uu (Corrected two values of
Table 3 into c3=-35.01 and c4=44.43 for "Upper F2p".
A Re-Evaluation of the nuclear Structure Function Ratios for D, He, Li, C and Ca
We present a re-evaluation of the structure function ratios F2(He)/F2(D),
F2(C)/F2(D) and F2(Ca)/F2(D) measured in deep inelastic muon-nucleus scattering
at an incident muon momentum of 200 GeV. We also present the ratios
F2(C)/F2(Li), F2(Ca)/F2(Li) and F2(Ca)/F2(C) measured at 90 GeV. The results
are based on data already published by NMC; the main difference in the analysis
is a correction for the masses of the deuterium targets and an improvement in
the radiative corrections. The kinematic range covered is 0.0035 < x < 0.65,
0.5 < Q^2 <90 GeV^2 for the He/D, C/D and Ca/D data and 0.0085 < x < 0.6, 0.84
< Q^2 < 17 GeV^2 for the Li/C/Ca ones.Comment: 6 pages, Latex, 3 figures as uuencoded compressed tar file included
at the end, in case of problems contact [email protected] (Antje
Bruell
Accurate Measurement of F2d/F2p and Rd-Rp
Results are presented for F2d/F2p and Rd-Rp from simultaneous measurements of
deep inelastic muon scattering on hydrogen and deuterium targets, at 90, 120,
200 and 280 GeV. The difference Rd-Rp, determined in the range 0.002<x<0.4 at
an average Q^2 of 5 GeV^2, is compatible with zero. The x and Q^2 dependence of
F2d/F2p was measured in the kinematic range 0.001<x<0.8 and 0.1<Q^2<145 GeV^2
with small statistical and systematic errors. For x>0.1 the ratio decreases
with Q^2.Comment: 29 pages, LateX, including figures, prepared with uufiles, arriving
with .sty files as used, figures .eps files and a table .tex file. Accepted
for publication in Nucl.Phys.B 199
The Structure Function Ratios F2(Li)/F2(D) and F2(C)/F2(D) at small x
We present the structure function ratios F2(Li)/F2(D) and F2(C)/F2(D)
measured in deep inelastic muon-nucleus scattering at a nominal incident muon
energy of 200 GeV. The kinematic range 0.0001 < x < 0.7 and 0.01< Q^2 < 70
GeV^2 is covered. For values of less than both ratios indicate
saturation of shadowing at values compatible with photoabsorption results
Ratio of J/Psi production cross sections in deep inelastic muon scattering from tin and carbon
Amaudruz P, Arneodo M, Arvidson A, et al. Ratio of J/Psi production cross sections in deep inelastic muon scattering from tin and carbon. Nucl.Phys. B. 1992;371(3):553-566.We present results on J/psi production in muon interactions with tin and carbon targets at incident muon energies of 200 and 280 GeV. The ratio of cross sections per nucleon for J/psi production on tin and carbon, R(Sn/C), is studied as a function of p(T)2, z and x. We find an enhancement for coherent J/psi production R(coh)(Sn/C) = 1.54 +/- 0.07, a suppression for quasielastic production R(qe)(Sn/C) = 0.79 +/- 0.06 and for inelastic production R(in)(Sn/C) = 1.13 +/- 0.08. The inelastic cross section ratio can be interpreted within the Colour Singlet model as an enhancement ot the gluon distribution in tin with respect to that in carbon. The dependence of the ratio on z and p(T)2 can explain the discrepancy between the results obtained in previous experiments
Quasielastic J/psi muoproduction from hydrogen, deuterium, carbon and tin
Arneodo M, Arvidson A, Badelek B, et al. Quasielastic J/psi muoproduction from hydrogen, deuterium, carbon and tin. Phys.Lett. B. 1994;332(1-2):195-200
Exclusive [Rho] 0 and [Phi] muoproduction at large Q 2
Arneodo M, Arvidson A, Badelek B, et al. Exclusive [Rho] 0 and [Phi] muoproduction at large Q 2. Nucl.Phys. B. 1994;429(3):503-529
Quark and gluon distributions and alpha-s from nucleon structure functions at low X
Arneodo M,, Arvidson A,, Badelek B,, et al. Quark and gluon distributions and alpha-s from nucleon structure functions at low X. Phys.Lett. B. 1993;309(1-2):222-230