P. Robmann

Learn More
A measurement of the proton structure function F 2 (x; Q 2) is reported for momentum transfers squared Q 2 between 4.5 GeV 2 and 1600 GeV 2 and for Bjorken x between 1:810 ?4 and 0:13 using data collected by the HERA experiment H1 in 1993. It is observed that F 2 increases signiicantly with decreasing x, connrming our previous measurement made with one(More)
Evidence is presented using data taken with the H1 detector at HERA for a class of deep inelastic electron{proton scattering (DIS) events (5 < Q 2 < 120 GeV 2) at low Bjorken-x (10 ?4 < x < 10 ?2) which have almost no hadronic energy ow in a large interval of pseudo-rapidity around the proton remnant direction and which cannot be attributed to our present(More)
We present a study of J== meson production in collisions of 26:7 GeV electrons with 820 GeV protons, performed with the H1-detector at the HERA collider at DESY. The J== mesons are detected via their leptonic decays both to electrons and muons. Requiring exactly two particles in the detector, a cross section of (ep ! J==X) = (8:8 2:0 2:2) nb is determined(More)
A search in the H1 experiment at HERA for scalar and vector leptoquarks, leptogluons and squarks coupling to rst generation fermions is presented in a data sample corresponding to an integrated luminosity of 425 nb ?1. For masses ranging up to 275 GeV, no signiicant evidence for the direct production of such particles is found in various possible decay(More)
Photoproduction of 2-jet events is studied with the H1 detector at HERA. Parton cross sections are extracted from the data by an unfolding method using leading order parton-jet correlations of a QCD generator. The gluon distribution in the photon is derived in the fractional momentum range 0:04 x 1 at the average factorization scale 75 GeV 2. H1(More)
An analysis is presented of scaling violations of the proton structure function F 2 (x; Q 2) measured with the H1 detector at HERA in the range of Bjorken x values between x = 310 ?4 and 10 ?2 for four-momentum transfers Q 2 larger than 8.7 GeV 2. The structure function F 2 (x; Q 2) is observed to rise linearly with lnQ 2. Under the assumption that the(More)
Measurements of ep scattering with squared 4{momentum transfer Q 2 up to 35000 GeV 2 are compared with the expectation of the standard deep-inelastic model of lepton{nucleon scattering (DIS). For Q 2 > 15000 GeV 2 , N obs = 12 neutral current candidate events are observed where the expectation is N DIS = 4:71 0:76 events. In the same Q 2 range, N obs = 4(More)
The proposed work is an extension of a program of precise studies of rare pion and muon decays using the PIBETA detector. In the first phase, 1999–2001, the collaboration completed a set of measurements of the π + → π 0 e + ν, π + → e + ν, π + → e + νγ, and µ + → e + ν ¯ νγ decays. Data for all of the decays except π → eνγ (π e2γ) are in excellent agreement(More)
A search for direct production of new leptons in the mass range from 10 GeV up to 225 GeV is presented by the H1 experiment at HERA. The data were obtained during 1993 and correspond to an integrated luminosity of 528 nb ?1. The search includes heavy lepton decays to nal states e () and e () W, e () Z with the subsequent decay of the W and Z bosons into(More)