Deep inelastic scattering and its diffractive component, ep -> e'y*p -> e'XN, have been studied at HERA with the ZEUS detector using an integrated luminosity of 4.2 pb(-1). The measurement covers a wide range in the y*p c.m. energy W (37-245 GeV), photon virtuality Q(2) (2.2-80 GeV(2)) and mass M(X) (0.28-35 GeV). The diffractive cross section for M(X) > 2 GeV rises strongly with W; the rise is steeper with increasing Q(2). The latter observation excludes the description of diffraclive deep inelastic scattering in terms of the exchange of a single pomeron. The ratio of diffractive to total cross section is constant as a function of W, in contradiction to the expectation of Regge phenomenology combined with a naive extension of the optical theorem to y*p scattering. Above M(X) of 8 GeV, the ratio is flat with Q(2), indicating a leading-twist behaviour of the diffractive cross section. The data are also presented in terms of the diffractive structure function, F(2)(D(3)) (beta, x(P), Q(2)) of the proton. For fixed beta, the Q(2) dependence of x(P)F2(D)((3)) changes with x(P) in violation of Regge factorisation. For fixed xp, x(P,) x(P)F(2)(D(3)) rises as beta -> 0, the rise accelerating with increasing Q(2). These positive scaling violations suggest substantial contributions of perturbative effects in the diffractive DIS cross section. (c) 2005 Elsevier B.V. All rights reserved

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The beauty production cross section for deep inelastic scattering events with at least one hard jet in the Breit frame together with a muon has been measured, for photon virtualities Q2>2 GeV2, with the ZEUS detector at HERA using integrated luminosity of 72 pb-1. The total visible cross section is Ï\u83bbÌ\u84(epâ\u86\u92e jet μX)=40.9±5.7(stat.)-4.4+6. 0(syst.) pb. The next-to-leading order QCD prediction lies about 2.5 standard deviations below the data. The differential cross sections are in general consistent with the NLO QCD predictions; however at low values of Q2, Bjorken x, and muon transverse momentum, and high values of jet transverse energy and muon pseudorapidity, the prediction is about two standard deviations below the data. © 2004 Published by Elsevier B.V

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This work is devoted to researching a phase transition in bismuth tellurite single crystals using a high-temperature X-ray analysis method. The cell parameter step-wise changes at 805• C are revealed. Starting from the data obtained we can say that the first-type transition takes place in bismuth tellurite. Key words: phase transition, bismuth tellurite, X-ray, diffraction maxima PACS: 61.50.KAuthors [1] consider that bismuth tellurite Bi 2 TeO 5 (BTO) possesses ferroelectric properties having undergone the second-type phase transition (PT) at the temperature about 780• C. BTO has Abm2 orthorhombic lattice a=11.602Å, b=16.461Å, c=5.523Å according to [2]. The BTO single crystal belongs to the continuous solid solution group of Bi 1−x Te x O (3+x)/2 [3]. It is presumed that subcell distorted of fluorite type with the side about 5.5Å is a basis of this solid solution structure. The unit-cell is formed by a multiplicity along cell axes 2x3x1 respectively. The temperature studies of changing cell parameters and symmetry have not been carried out earlier. Therefore the aim of this work is X-ray research of Bi 2 TeO 5 single crystals in a wide temperature range including the area of phase transition supposed.The (100), (010) and (001) single crystal plates oriented and polished with the size of 10x15x2 mm 3 and the powder of the Bi 2 TeO 5 single crystals grown were used. The single crystal boules of bismuth tellurite were prepared as in the work [4] from the melt by the Czochralski technique at the starting ratio of the Bi 2 O 3 and TeO 2 components 47 and 53 mole % respectively. The sample X-ray patterns were recorded with the DRON 2.0 difractometer (Co Kα -radiation filtered). For the hightemperature measurements the UVD-2000 accessory was used. In table 1 the positions and the relative intensities of X-ray maxima from the BTO single crystal powder are presented at room temperature. The difractograms of BTO single crystal cuts show a=11.616Å, b=16.451Å and c=5.524Å at room temperature and systematic extinctions for oriented plates taking into account non-centrosymmetry are stowed to the Abm2 space group.