E.N. Koffeman

Measurement of the proton structure function F-2 at very low Q(2) at HERA

A measurement of the proton structure function F_2(x,Q^2) is presented in the kinematic range 0.045 GeV^2<Q^2<0.65 GeV^2 and 6*10^{-7}<x<1*10^{-3}. The results were obtained using a data sample corresponding to an integrated luminosity of 3.9pb^-1 in e^+p reactions recorded with the ZEUS detector at HERA. Information from a silicon-strip tracking detector, installed in front of the small electromagnetic calorimeter used to measure the energy of the final-state positron at small scattering angles, together with an enhanced simulation of the hadronic final state, has permitted the extension of the kinematic range beyond that of previous measurements. The uncertainties in F_2 are typically less than 4%. At the low Q^2 values of the present measurement, the rise of F_2 at low x is slower than observed in HERA data at higher Q^2 and can be described by Regge theory with a constant logarithmic slope. The dependence of F_2 on Q^2 is stronger than at higher Q^2 values, approaching, at the lowest Q^2 values of this measurement, a region where F_2 becomes nearly proportional to Q^2.A measurement of the proton structure function F-2(x, Q(2)) is presented in the kinematic range 0.045 GeV2 lt Q(2) lt 0.65 GeV2 and 6 . 10(-7) lt x lt 1 . 10(-3). The results were obtained using a data sample corresponding to an integrated luminosity of 3.9 pb(-1) in e(+)p reactions recorded with the ZEUS detector at HERA. Information from a silicon-strip tracking detector, installed in front of the small electromagnetic calorimeter used to measure the energy of the final-state positron at small scattering angles, together with an enhanced simulation of the hadronic final state, has permitted the extension of the kinematic range beyond that of previous measurements. The uncertainties in F-2 are typically less than 4%. At the low Q(2) values of the present measurement, the rise of F-2 at low x is slower than observed in HERA data at higher Q(2) and can be described by Regge theory with a constant logarithmic slope partial derivative lnF(2)/partial derivative ln(1/x). The dependence of F-2 on Q(2) is stronger than at higher Q(2) values, approaching, at the lowest Q(2) values of this measurement, a region where F-2 becomes nearly proportional to Q(2).

Measurement of D*(+/-) production and the charm contribution to F-2 in deep inelastic scattering at HERA

Abstract. The production of n

Measurement of open beauty production in photoproduction at HERA

D^{ast pm}

Measurement of exclusive omega electroproduction at HERA

(2010) mesons in deep inelastic scattering has been measured in the ZEUS detector at HERA using an integrated luminosity of 37 pbn

Measurement of inclusive prompt photon photoproduction at HERA

^{-1}

Measurement of azimuthal asymmetries in deep inelastic scattering

. The decay channels n

Dijet production in neutral current deep inelastic scattering at HERA

D^{ast +}rightarrow D^0 pi^+

Measurement of inclusive ( D s ± ) photoproduction at HERA

(+ c.c.), with n

W production and the search for events with an isolated high-energy lepton and missing transverse momentum at HERA

D^0 rightarrow K^- pi^+

Measurement of dijet cross sections for events with a leading neutron in photoproduction at HERA

or n