115684115
Some consequences for LHC experiments from the results of cosmic ray investigations above the knee
Experimental data obtained in cosmic ray investigations at energies above the knee are discussed. All features observed at these energies starting from the knee, changes of mass composition and concluding with various types of unusual events are analysed in the framework of the new hadron interaction model producing blobs of quark gluon matter. Consequences for LHC experiments are considered.
119359927
Measurements of integral muon intensity at large zenith angles
High-statistics data on near-horizontal muons collected with Russian-Italian coordinate detector DECOR are analyzed. Precise measurements of muon angular distributions in zenith angle interval from 60 to 90 degrees have been performed. In total, more than 20 million muons are selected. Dependences of the absolute integral muon intensity on zenith angle for several threshold energies ranging from 1.7 GeV to 7.2 GeV are derived. Results for this region of zenith angles and threshold energies have been obtained for the first time. The dependence of integral intensity on zenith angle and threshold energy is well fitted by a simple analytical formula.
118513317
Cosmic rays and new physics
126177483
The role of VHE muons in an explanation of unusual events observed in cosmic rays
Unusual events observed in cosmic-ray experiments that cannot be explained in the context of modern theories and models are considered. The peculiarities of VHE (>= 100 TeV) muon interactions and their possible contribution to the production of various unusual events in cosmic rays are analyzed. Some preliminary results obtained in relation to unusual events detected in the Tien Shan calorimeter and in the Pamir experiment are discussed.
119824011
Time distribution of electromagnetic and hadronic components in giant EAS
HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Time distribution of electromagnetic and hadronic components in giant EAS J-N. Capdevielle, F. Cohen, A. Aynutdinov, A. Petrukhin
121417204
Cosmic ray neutrino detection on the ground level
Abstract The Cherenkov water detector with volume 2000 m 3 for registration of ν-induced muons from the bottom hemisphere on the ground level was constructed. First results of muon detection are described. Methods of atmospheric muon flux suppression and possibility to reach the rejection factor necessary for separation of ν-induced muons are discussed.
54014486
Photoproduction—DIS Transition
Recent measurements of the proton structure function F2 at low Q2 in e+p deep inelastic scattering (DIS) by the H1 Collaboration are summarized. This measurements are performed in the region of low squared four‐momentum transfers, 0.2 GeV2⩽Q2⩽12 GeV2, and low Bjorken x, 5⋅10−6⩽x⩽0.02.
116603302
Structure Function Measurements at HERA
Recent structure function results from the H1 and ZEUS Collaborations are presented. The data cover a wide kinematic range of squared four-momentum transfers Q^2, from 0.2 GeV^2 to 30000 GeV^2, and Bjorken x between 5*10^-6 and 0.65. Data from both experiments have been combined, leading to significantly reduced experimental uncertainties. The combined measurements are analysed using a NLO QCD fit, and a set of parton density functions, HERAPDF1.0, is extracted. New direct measurements of the structure function F_L, making use of dedicated low energy runs of the HERA machine, are also presented.
118735964
Measurements of the proton structure at HERA and their impact for LHC
Recent results on proton structure functions from H1 and ZEUS Collaborations are presented. The data have been recorded in e + p and e − p collisions for both Neutral Current and Charged Current reactions, covering a wide kinematic range of squared four-momentum transfers Q 2 , from 0.2 GeV 2 to 30000 GeV 2 , and Bjorken x between ∼ 5 ⁎ 10 − 6 and 0.65. Data from both experiments have been combined, leading to significantly reduced experimental uncertainties. The combined measurements are analysed in a NLO QCD fit, and a set of parton density functions, HERAPDF1.0, is extracted from these data alone. New direct measurements of the structure function F L , making use of dedicated low energy runs of the HERA machine, are also presented. The impact of the HERA data on the parton density functions and predictions for LHC is discussed.
124965491
Structure functions measurements at HERA
The measurements of the DIS cross sections at low Q (from 0.2GeV to 12GeV) [1] and medium Q (from 12GeV to 150GeV) [2] are based on data collected by the H1 Collaboration in 1999-2000. In order to access low values of Q around 1 GeV the interaction vertex, for short period of H1 2000 data taking, was shifted by approximately 70 cm along the proton beam direction. This data sample is also used for accessing larger values of x with Initial State Radiation (ISR) events. Data collected by the H1 Collaboration in 1999 with a nominal position of the interaction vertex are used for measurements in the region of high inelasticity y. These data are combined with H1 data taken in 1995-1997 following the prescription introduced in [3]. The H1 measurements at low and medium Q are shown in Figure 1. These are the most precise results of the H1 Collaboration in the given kinematic domain. The accuracy of the combined measurements is typically at the level of 1-2%. The H1 data alone is used in a NLO QCD analysis to determine a new set of parton densities called H1PDF2009.
31393010
Measurement of the Inclusive ep Scattering Cross Section at HERA
Measurements of the inclusive ep scattering cross section are presented in the wide region of four-momentum transfers squared, 0.2 GeV 2 ⩽ Q 2 ⩽ 30000 GeV 2 , and Bjorken x , 4 ⋅ 10 −6 ≲ x ≲ 0.8 . The results are based on data sets collected by the H1 and ZEUS collaborations at HERA. The data include the region of high inelasticity y up to 0.9, which is sensitive to the longitudinal proton structure function F L ( x , Q 2 ) .