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1.
We examine deep inelastic scattering using methods which have been successfully applied to study inclusive scattering of GeV electrons by nuclei. We find that the consistent inclusion of the binding effects allows to describe much better the data on nuclear matter to deuteron cross section ratios in the region of large x where binding fully accounts for the deviation of the cross section ratio from one.  相似文献   

2.
The dominant electromagnetic radiative corrections to neutral current deep inelastic scattering at HERA energies have been calculated analytically in collinear approximation for unpolarized beams. The results may be used for the construction of an event generator and are applied to discuss the influence of cuts on the magnitude of the correction. For final state collinear photon emission the measurement of the resulting electromagnetic jet (electron plus collinear photon) reducesx-andy-dependence of the correction factor. Electromagnetic corrections to charged current interactions are discussed in leading logarithmic approximation.  相似文献   

3.
The nuclear effects in the neutrino–nucleus charged-current inelastic scattering process is studied by analyzing the CCFR and NuTeV data. The structure functions F2(x,Q2) and xF3(x,Q2) as well as differential cross sections are calculated by using CTEQ parton distribution functions and the EKRS and HKN nuclear parton distribution functions, and these are compared with the CCFR and NuTeV data. It is found that the corrections of the nuclear effect to the differential cross section for the charged-current antineutrino scattering on the nucleus are negligible, the EMC effect exists in the neutrino structure function F2(x,Q2) in the large x region, the shadowing and anti-shadowing effect occur in the distribution functions of valence quarks in the small and medium x region, respectively. It is also found that shadowing effects on F2(x,Q2) in the small x region in the neutrino–nucleus and the charged-lepton–nucleus deep inelastic scattering processes are different. It is clear that the neutrino–nucleus deep inelastic scattering data should further be employed in restricting the nuclear parton distributions. PACS 13.15.+g; 24.85.+p; 25.30.-c  相似文献   

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We consider Next-to-Leading-Order QCD corrections to ADD graviton exchange relevant for Deep Inelastic Scattering experiments. We calculate the relevant NLO structure functions by calculating the virtual and real corrections for a set of graviton interaction diagrams, demonstrating the expected cancellation of the UV and IR divergences. We compare the NLO and LO results at the centre-of-mass energy relevant to HERA experiments as well as for the proposed higher energy lepton–proton collider, LHeC, which has a higher fundamental scale reach.  相似文献   

7.
Analytic results are presented on electroweak radiative corrections for neutral-current deepinelastic electron proton scattering at HERA energies. Single photon bremsstrahlung is included without cuts.  相似文献   

8.
Ikka Liede 《Nuclear Physics B》1983,229(2):499-508
The electromagnetic (EM) radiative corrections to the inclusive νN deep inelastic charged and neutral-current (CC and NC) scattering are studied in the on-shell renormalization scheme of the standard electroweak (EW) model.  相似文献   

9.
Thermal effects for inelastic neutrino-nucleus scattering off even-even nuclei in the iron region are studied. Allowed and first-forbidden contributions to the cross sections are calculated within the quasiparticle random-phase approximation, extended to finite temperatures within the Thermo-Field-Dynamics formalism. The GT0 strength distribution at finite temperatures is calculated for the sample nucleus 54Fe. The neutral-current neutrino-nucleus inelastic cross section is calculated for relevant temperatures during the supernova core collapse. The thermal population of the excited states significantly enhances the cross section at low neutrino energies. In agreement with studies using a large scale shell-model approach the enhancement is mainly due to neutrino up-scattering at finite temperatures.  相似文献   

10.
A serious problem caused by large radiative corrections in deep inelastic scattering is indicated. A simple way how to avoid a principal difficulty related to it is suggested.An abreviated version of this article was presented as a contribution to Hadron Structure '90 conference at Smolenice castle, Czechoslovakia, 25 October, 1990.  相似文献   

11.
Analytic results are presented on electroweak radiative corrections for charged-current deep-inelastic electron proton scattering at HERA energies. Single photon bremsstrahlung is included without cuts.  相似文献   

12.
We present the perturbative QCD analysis of nuclear shadowing in deep inelastic scattering and prove it to be the scaling, rather than the higher twist, 1/Q2, effect, contrary to numerous recent claims. We argue in favor of the scaling triple-pomeron contribution to the nuclear shadowing and comment on the mass spectrum of diffraction excitation by highly virtual photons. Our numerical predictions for shadowing are in good agreement with the recent EMC data.  相似文献   

13.
《Physics letters. [Part B]》1988,211(4):493-499
Results are presented on the ratio of the inelastic muon-nucleus cross section per nucleon for carbon and calcium relative to that for deuterium. The measurements were made in the kinematic range of low x (0.003–0.1) and low Q2 (0.3–3.2 GeV2) at an incident muon energy of 280 GeV. The calcium to deuterium ratio shows a significant x dependence which is interpreted as a shadowing effect. No strong Q2 dependence is observed. This suggests that the effect is due at least partially to parton interactions within the nucleus.  相似文献   

14.
We find new evidence for higher order asymptotic freedom corrections to the moments of the proton structure function in electron, muon scattering for spins n ? 4. We show that it is unlikely that this effect can be associated in any simple way with higher-twist effects.  相似文献   

15.
A new global analysis of deep inelastic scattering data   总被引:1,自引:0,他引:1  
A new QCD analysis of deep inelastic scattering (DIS) data is presented. All available neutrino and antineutrino cross sections are reanalyzed and included in the fit, along with charged-lepton DIS and Drell–Yan data. A massive factorization scheme is used to describe the charm component of the structure functions. Next-to-leading-order parton distribution functions are provided. In particular, the strange-sea density is determined with a higher accuracy with respect to other global fits. Received: 16 March 1999 / Published online: 8 December 1999  相似文献   

16.
It is shown that the EMC-effect can be explained by the nuclear structure. The binding of nucleons is shown to play an important role. The contributions of mesons to the nuclear structure functions are discussed.  相似文献   

17.
Based on the shell model for Gamow-Teller and the random phase approximation for forbidden transitions, we calculate cross sections for inelastic neutrino-nucleus scattering (INNS) under supernova (SN) conditions, assuming a matter composition given by nuclear statistical equilibrium. The cross sections are incorporated into state-of-the-art stellar core-collapse simulations with detailed energy-dependent neutrino transport. While no significant effect on the SN dynamics is observed, INNS increases the neutrino opacities noticeably and strongly reduces the high-energy tail of the neutrino spectrum emitted in the neutrino burst at shock breakout. Relatedly the expected event rates for the observation of such neutrinos by earthbound detectors are reduced by up to about 60%.  相似文献   

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We present the perturbative QCD analysis of nuclear shadowing in the deep inelastic scattering at smallx in terms of the spatial wave function ofq \(\bar q\) fluctuations of virtual photons. The wave function formalism makes it quite obvious that shadowing is the scaling, rather than the higher twist, 1/Q 2, effect, contrary to a numerous recent claims. We demonstrate explicitly how the scaling shadowing comes from the large, hadronic, size quarkantiquark pairs even in the limit ofQ 2→∞, and why it should very slowly, ∞1/log (Q 2/m 2) decrease at very largeQ 2. We argue in favor of the scaling triple-pomeron contribution to the nuclear shadowing and present predictions for a cross section of diffraction dissociation of virtual photons and for the mass spectrum of diffraction excitation, which can be checked at HERA and Fermilab. We predict strikingly different scaling properties of diffraction dissociation and nuclear shadowing for the longitudinal and transverse photons. Our, numerial predictions for shadowing are in good agreement with the recent EMC data.  相似文献   

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