Measurement and QCD analysis of neutral and charged current cross sections at HERA.

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Eur.Phys.J.C 30 (2003) 1-32, 2003.
Inspire Record 616311 DOI 10.17182/hepdata.11903

The inclusive e^+ p single and double differential cross sections for neutral and charged current processes are measured with the H1 detector at HERA. The data were taken in 1999 and 2000 at a centre-of-mass energy of \sqrt{s} = 319 GeV and correspond to an integrated luminosity of 65.2 pb^-1. The cross sections are measured in the range of four-momentum transfer squared Q^2 between 100 and 30000 GeV^2 and Bjorken x between 0.0013 and 0.65. The neutral current analysis for the new e^+ p data and the earlier e^- p data taken in 1998 and 1999 is extended to small energies of the scattered electron and therefore to higher values of inelasticity y, allowing a determination of the longitudinal structure function F_L at high Q^2 (110 - 700 GeV^2). A new measurement of the structure function x F_3 is obtained using the new e^+ p and previously published e^\pm p neutral current cross section data at high Q^2. These data together with H1 low Q^2 precision data are further used to perform new next-to-leading order QCD analyses in the framework of the Standard Model to extract flavour separated parton distributions in the proton.

21 data tables

The NC cross section DSIG/DQ**2. There is an additional 1.5 PCT normalization uncertainty.

The CC cross section DSIG/DQ**2. There is an additional 1.5 PCT normalization uncertainty.

The NC cross section DSIG/DX for Q**2 > 1000 GeV**2. There is an additional 1.5 PCT normalization uncertainty.

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Measurement of neutral and charged current cross-sections in electron - proton collisions at high Q**2

The H1 collaboration Adloff, C. ; Andreev, V. ; Andrieu, B. ; et al.
Eur.Phys.J.C 19 (2001) 269-288, 2001.
Inspire Record 539088 DOI 10.17182/hepdata.46812

The inclusive e^-p single and double differential cross sections for neutral and charged current processes are measured with the H1 detector at HERA, in the range of four-momentum transfer squared Q^2 between 150 and 30000 GeV^2, and Bjorken x between 0.002 and 0.65. The data were taken in 1998 and 1999 with a centre-of-mass energy of 320 GeV and correspond to an integrated luminosity of 16.4 pb^(-1). The data are compared with recent measurements of the inclusive neutral and charged current e^+p cross sections. For Q^2>1000 GeV^2 clear evidence is observed for an asymmetry between e^+p and e^-p neutral current scattering and the generalised structure function xF_3 is extracted for the first time at HERA. A fit to the charged current data is used to extract a value for the W boson propagator mass. The data are found to be in good agreement with Standard Model predictions.

12 data tables

The NC single differential cross section, as a function of X, for Y < 0.9 and Q**2 > 1000 GeV**2. The first DSYS error is the uncorrelated systematic errorand the second is the correlated systematic error.

The NC single differential cross section, as a function of X, for Y < 0.9 and Q**2 > 10000 GeV**2. The first DSYS error is the uncorrelated systematic error and the second is the correlated systematic error.

The CC single differential cross section, as a function of X, for measured for 0.03 < Y < 0.85 and Q**2 > 1000 GeV**2. and corrected by KCOR to Y < 0.9. The first DSYS error is the uncorrelated systematic error and the second is the correlated systematic error.

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Measurements of the Q**2 dependence of the proton and neutron spin structure functions g1(p) and g1(n).

The E155 collaboration Anthony, P.L ; Arnold, R.G ; Averett, T ; et al.
Phys.Lett.B 493 (2000) 19-28, 2000.
Inspire Record 530798 DOI 10.17182/hepdata.27035

The structure functions g1p and g1n have been measured over the range 0.014 < x < 0.9 and 1 < Q2 < 40 GeV2 using deep-inelastic scattering of 48 GeV longitudinally polarized electrons from polarized protons and deuterons. We find that the Q2 dependence of g1p (g1n) at fixed x is very similar to that of the spin-averaged structure function F1p (F1n). From a NLO QCD fit to all available data we find $\Gamma_1^p - \Gamma_1^n =0.176 \pm 0.003 \pm 0.007$ at Q2=5 GeV2, in agreement with the Bjorken sum rule prediction of 0.182 \pm 0.005.

12 data tables

Results for G1/F1 for the proton and neutron.

Results for G1/F1 for the proton and neutron.

Results for G1/F1 for the proton and neutron.

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Measurement of the proton and deuteron spin structure functions g2 and asymmetry A(2).

The E155 collaboration Anthony, P.L. ; Arnold, R.G. ; Averett, T. ; et al.
Phys.Lett.B 458 (1999) 529-535, 1999.
Inspire Record 493768 DOI 10.17182/hepdata.27072

We have measured the spin structure functions g2p and g2d and the virtual photon asymmetries A2p and A2d over the kinematic range 0.02 < x < 0.8 and 1.0 < Q^2 < 30(GeV/c)^2 by scattering 38.8 GeV longitudinally polarized electrons from transversely polarized NH3 and 6LiD targets.The absolute value of A2 is significantly smaller than the sqrt{R} positivity limit over the measured range, while g2 is consistent with the twist-2 Wandzura-Wilczek calculation. We obtain results for the twist-3 reduced matrix elements d2p, d2d and d2n. The Burkhardt-Cottingham sum rule integral - int(g2(x)dx) is reported for the range 0.02 < x < 0.8.

4 data tables

2.75 degree spectrometer data.

5.5 degree spectrometer data.

10.5 degree spectrometer data.

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Measurements of the proton and deuteron spin structure functions g1 and g2.

The E143 collaboration Abe, K. ; Akagi, T. ; Anthony, P.L. ; et al.
Phys.Rev.D 58 (1998) 112003, 1998.
Inspire Record 467140 DOI 10.17182/hepdata.22265

Measurements are reported of the proton and deuteron spin structure functions g1 at beam energies of 29.1, 16.2, and 9.7 GeV and g2 at a beam energy of 29.1 GeV. The integrals of g1 over x have been evaluated at fixed Q**2 = 3 (GeV/c)**2 using the full data set. The Q**2 dependence of the ratio g1/F1 was studied and found to be small for Q**2 > 1 (GeV/c)**2. Within experimental precision the g2 data are well-described by the Wandzura-Wilczek twist-2 contribution. Twist-3 matrix elements were extracted and compared to theoretical predictions. The asymmetry A2 was measured and found to be significantly smaller than the positivity limit for both proton and deuteron targets. A2 for the proton is found to be positive and inconsistent with zero. Measurements of g1 in the resonance region show strong variations with x and Q**2, consistent with resonant amplitudes extracted from unpolarized data. These data allow us to study the Q**2 dependence of the first moments of g1 below the scaling region.

33 data tables

Averaged A1(P) for the DIS (W**2 > 4 GeV) region. Additional normalization uncertainty 3.7%.

Detailed A1(P) for the DIS (W**2 > 4 GeV) region. Additional normalization uncertainty 3.7%.

Detailed A1(P) for the DIS (W**2 > 4 GeV) region. Additional normalization uncertainty 3.7%.

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Deep Inelastic Scattering of Polarized Electrons by Polarized $^3$He and the Study of the Neutron Spin Structure

The E142 collaboration Anthony, P.L. ; Arnold, R.G. ; Band, H.R. ; et al.
Phys.Rev.D 54 (1996) 6620-6650, 1996.
Inspire Record 424108 DOI 10.17182/hepdata.22340

The neutron longitudinal and transverse asymmetries $A^n_1$ and $A^n_2$ have been extracted from deep inelastic scattering of polarized electrons by a polarized $^3$He target at incident energies of 19.42, 22.66 and 25.51 GeV. The measurement allows for the determination of the neutron spin structure functions $g^n_1 (x,Q^2)$ and $g^n_2(x,Q^2)$ over the range $0.03 < x < 0.6$ at an average $Q^2$ of 2 (GeV$/c)^2$. The data are used for the evaluation of the Ellis-Jaffe and Bjorken sum rules. The neutron spin structure function $g^n_1 (x,Q^2)$ is small and negative within the range of our measurement, yielding an integral ${\int_{0.03}^{0.6} g_1^n(x) dx}= -0.028 \pm 0.006 (stat) \pm 0.006 (syst) $. Assuming Regge behavior at low $x$, we extract $\Gamma_1^n=\int^1_0 g^n_1(x)dx = -0.031 \pm 0.006 (stat)\pm 0.009 (syst) $. Combined with previous proton integral results from SLAC experiment E143, we find $\Gamma_1^p - \Gamma_1^n = 0.160 \pm 0.015$ in agreement with the Bjorken sum rule prediction $\Gamma^p_1 - \Gamma ^n_1 = 0.176 \pm 0.008$ at a $Q^2$ value of 3 (GeV$/c)^2$ evaluated using $\alpha_s = 0.32\pm 0.05$.

12 data tables

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Measurement of the proton and deuteron spin structure function g1 in the resonance region.

The E143 collaboration Abe, K. ; Akagi, T. ; Anthony, P.L. ; et al.
Phys.Rev.Lett. 78 (1997) 815-819, 1997.
Inspire Record 426735 DOI 10.17182/hepdata.19582

We have measured the proton and deuteron spin structure functions g_1^p and g_1^d in the region of the nucleon resonances for W^2 &lt; 5 GeV^2 and $Q^2\simeq 0.5$ and $Q^2\simeq 1.2$ GeV^2 by inelastically scattering 9.7 GeV polarized electrons off polarized $^{15}NH_3$ and $^{15}ND_3$ targets. We observe significant structure in g_1^p in the resonance region. We have used the present results, together with the deep-inelastic data at higher W^2, to extract $\Gamma(Q^2)\equiv\int_0^1 g_1(x,Q^2) dx$. This is the first information on the low-Q^2 evolution of Gamma toward the Gerasimov-Drell-Hearn limit at Q^2 = 0.

8 data tables

The integral of the structure functions g1 for the resonance region W**2 < 4 GeV**2.

The integral of the structure functions g1 for the resonance region W**2 < 4 GeV**2.

The integral of the structure functions g1 for the full W region including the deep-inelastic region as given by fits to the world's data.

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Measurement of the $Q~{2}$ dependence of the Charged and Neutral Current Cross Sections in $e~{\pm}p$ Scattering at HERA

The H1 collaboration Aid, S. ; Andreev, V. ; Andrieu, B. ; et al.
Phys.Lett.B 379 (1996) 319-329, 1996.
Inspire Record 417155 DOI 10.17182/hepdata.44768

The $Q~{2}$ dependence and the total cross sections for charged and neutral current processes are measured in $e~{\pm}p$ reactions for transverse momenta of the outgoing lepton larger than 25 GeV. Comparable size of cross sections for the neutral current process and for the weak charged current process are observed above $Q~2\approx5000$GeV$~2$. Using the shape and magnitude of the charged current cross section we determine a propagator mass of $m_{W} = 84\ ~{+10}_{-7}$ GeV.

4 data tables

No description provided.

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Total cross-section for E-P events.

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Measurements of the Q**2 dependence of the proton and deuteron spin structure functions g1(p) and g1(d)

The E143 collaboration Abe, K. ; Akagi, T. ; Anthony, P.L. ; et al.
Phys.Lett.B 364 (1995) 61-68, 1995.
Inspire Record 401107 DOI 10.17182/hepdata.28431

The ratio g1/F1 has been measured over the range 0.03<x<0.6 and 0.3<Q2<10 (GeV/c)2 using deep-inelastic scattering of polarized electrons from polarized protons and deuterons. We find g1/F1 to be consistent with no Q2-dependence at fixed x in the deep-inelastic region Q~2>1 (GeV/c)2. A trend is observed for g1/F1 to decrease at lower Q2. Fits to world data with and without a possible Q2-dependence in g1/F1 are in agreement with the Bjorken sum rule, but Delta_q is substantially less than the quark-parton model expectation.

16 data tables

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Measurement of the total photon-proton cross-section and its decomposition at 200-GeV center-of-mass energy

The H1 collaboration Aid, S. ; Andreev, V. ; Andrieu, B. ; et al.
Z.Phys.C 69 (1995) 27-38, 1995.
Inspire Record 399015 DOI 10.17182/hepdata.44969

We present a new measurement of the total photoproduction cross section performed with the H1 detector at HERA. For an average centre of mass energy of 200GeV a value of $\sigma_{tot}~{\gamma{p}}= 165\pm2\pm11\mu$b has been obtained. A detailed analysis of the data in adequate kinematic regions enabled a decomposition of the total cross section in its elastic, single diffractive dissociation and remaining non-diffractive parts, based on safe assumptions on the double diffractive dissociation contribution.

2 data tables

No description provided.

Total GAMMA P cross section.