Showing papers by "Hermann Kolanoski published in 1995"
TL;DR: In this paper, a measurement of the contribution of diffractive interactions to deep-inelastic electron-proton (ep) scattering in the kinematic range 8.5 × 10−4 < Bjorken-x < 0.0133, and 3.7 × 10 −4 < χp <0.043.
163 citations
TL;DR: In this article, a measurement of the proton structure function was reported for momentum transfer squared Q^2 between 4.5 GeV^2 and 1600 GeV+2 and for Bjorken x between 1.8\cdot10^{-4} and 0.13 using data collected by HERA experiment H1 in 1993.
158 citations
TL;DR: In this article, the authors measured the production of transverse energy in deep inelastic scattering using the H1 detector at the ep collider HERA and compared the different predictions based upon two alternative QCD evolution equations, namely the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) and the Balitsky-Fadin-Kuraev-Linatov (BFKL) equations.
59 citations
TL;DR: In this paper, the authors derived the gluon distribution in the photon in the fractional momentum range 004 ⩽ xγ⩽ 1 at the average factorization scale 75 GeV2.
50 citations
TL;DR: In this article, a QCD analysis of the proton structure function F 2 measured by the H1 experiment at HERA, combined with data from previous fixed target experiments is presented, and the gluon density is extracted from the scaling violations of F 2 in the range 2 · 10 −4 x −2 and compared with an approximate solution of the QCD evolution equations.
45 citations
01 Jan 1995
TL;DR: HERA halo target inside the HERA proton ring is used to generate the B mesons in 820 GeV proton-nucleus interactions as mentioned in this paper, and the feasibility of the high rate target operation and the design and status of the detector are discussed.
Abstract: HERA-B is a xed target experiment dedicated to study CP violation in the decay of neutral B mesons into the "gold plated" decay mode B 0 ! J==K 0 s. A halo target inside the HERA proton ring is used to generate the B mesons in 820 GeV proton-nucleus interactions. This article reviews the goals and expected performance of the experiment, the feasibility of the high rate target operation and the design and status of the detector.
39 citations
TL;DR: In this article, the Breit frame of reference was used to study the effects of deep inelastic scattering (DIS) on the invariant square of the four-momentum transfer in pArton showers.
38 citations
TL;DR: In this paper, an improved upper bound for two-body τ-decays into a lepton and an unobservable particle was obtained using the pseudo-rest-frame technique.
Abstract: Lepton spectra in τ decays have been studied with the ARGUS detector at thee+e− storage ring DORIS II at DESY using the “pseudo-rest-frame” technique. We have improved upper limits for two-body τ-decays into a lepton and an unobservable particle.
34 citations
TL;DR: In this article, the authors presented a new measurement of the total photoproduction cross section performed with the H1 detector at HERA, for an average center of mass energy of 200 GeV, and obtained a value of σtotλp=165±2±11µb.
Abstract: We present a new measurement of the total photoproduction cross section performed with the H1 detector at HERA. For an average centre of mass energy of 200 GeV a value of σtotλp=165±2±11µb has been obtained. A detailed analysis of the data in adequate kinematic regions enabled a decomposition of the total cross section in its elastic, single diffractive dissociation and remaining non-diffractive parts, based on safe assumptions on the double diffractive dissociation contribution.
32 citations
TL;DR: In this article, hard scattering in photon diffractive dissociation is demonstrated using single particle spectra, thrust as a function of transverse energy, and the observation of jet production.
29 citations
11 Dec 1995-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: The use of feed-forward nets is most common for event classification and function approximation and this network type is best suited for a hardware implementation and special VLSI chips are available which are used in fast trigger processors.
Abstract: The application of artificial neural networks in particle physics is reviewed. The use of feed-forward nets is most common for event classification and function approximation. This network type is best suited for a hardware implementation and special VLSI chips are available which are used in fast trigger processors. Also discussed are fully connected networks of the Hopfield type for pattern recognition in tracking detectors.
TL;DR: In this article, the H1 detector at HERA was used to study the jet rates in deep inelastic electron proton scattering with a perturbative QCD in next-leading order.
TL;DR: In this paper, a contact interaction analysis is presented to search for new phenomena beyond the Standard Model in deep inelastic e ± p → e ± hadrons scattering. But the analysis is limited to the case of the H1 detector at HERA.
TL;DR: In this paper, the authors present an experimental study of theep→eγ+p andep→ eγ+X processes using data recorded by the H1 detector in 1993 at the electron-proton collider HERA.
Abstract: We present an experimental study of theep→eγ+p andep→eγ+X processes using data recorded by the H1 detector in 1993 at the electron-proton collider HERA These processes are employed to measure the luminosity with an accuracy of 45 % A subsample of theep→eγ+X events in which the hard photon is detected at angles θγ′ ≤ 045 mrad with respect to the incident electron direction is used to verify experimentally the size of radiative corrections to theep→eX inclusive cross section and to investigate the structure of the proton in theQ2 domain down to 2 GeV2, lower than previously attained at HERA
TL;DR: In this paper, the authors used the ARGUS detector at the e + e − storage ring DORIS II to determine the Michel parameters ξ and δ of τ ∓ → l ∓ ν ν -decays.
TL;DR: A leading order determination of the gluon density in the proton has been performed in the fractional momentum range 1.9 · 10−3 as discussed by the authors, where the number of gluons in a proton is 1.
TL;DR: In this article, a pseudo-rest-frame technique was used to obtain the first measurement of the Michel Parameter 7/in ~-decays with a precision comparable to the present world average.
TL;DR: In this paper, the transverse energy flow and relative rates of large rapidity gap events are compared in the two event samples at the high energy electron-proton collider HERA, where the observed similarity between γp and γ ∗ p interactions can be understood in a picture where the photon develops as a hadronic object.
TL;DR: The cross sections for the charged current processes were measured at HERA for transverse momenta larger than 25 GeV in this article, and the cross sections of the charge current processes for the first time were measured in HERA.
Abstract: The cross sections for the charged current processes {ie566-1} and, for the first time, {ie566-2} are measured at HERA for transverse momenta larger than 25 GeV.
TL;DR: In this paper, the ARGUS detector at the storage ring DORIS II has measured τ decays into three charged mesons containing K* mesons and determined the following branching ratios:Br(τ−→K*−X0vτ) =(1.15±0.15−0.13)%.
Abstract: Using the ARGUS detector at the storage ring DORIS II we have measured τ decays into three charged mesons containingK* mesons. Exploiting the good particle identification capabilities of the detector we have determined the following branching ratios:\(Br\left( {\tau ^ - \to \overline {K^{*0} } \pi ^ - v_\tau } \right) = \left( {0.25 \pm 0.10 \pm 0.05} \right)\% \),Br(τ−→K*0K−vτ)= (0.20±0.05±0.04)%, andBr(τ−→K*−X0vτ) =(1.15±0.15−0.18+0.13)%.
TL;DR: In this paper, the ARGUS detector at the e+e− storage ring DORIS II at DESY was used to search for decays b → sgluon through full reconstruction of a whole event.
TL;DR: In this article, the partial decay width of the ϒ(4S) resonance and its partial width into electrons were measured with the detector ARGUS at the DORISII of DESY.
Abstract: The partial decay width into electrons, Γ ee , of the ϒ(1S) and ϒ(2S) resonances have been measured with the detector ARGUS at thee+e− storage ring DORISII of DESY. Applying the formula of Kuraev and Fadin for the radiative corrections we find: Γ ee (ϒ(1S))= (1.32±0.04±0.03) keV and Γ ee (ϒ(2S))=(0.52±0.03±0.01) keV. The total decay width of the ϒ(4S) resonance and its partial width into electrons have been determined as well. Fitting the data with a generalized Breit-Wigner function with an energy dependent decay width Γ(s) and a mass shift functionm(s), we obtain the following resonance parameters: Γ(M2)=(10.0±2.8±2.7) MeV, Γ ee =(0.28±0.05±0.01)keV andB ee =(2.77±0.50±0.49)·10−5. We argue that the disagrecment of this result with the world average originates from our more adequate parametrization of the observed ϒ(4S) resonance cross section.
TL;DR: Using the ARGUS detector at the DORIS II electron-positron storage ring at DESY, the authors have measured BR(D*+→D0π+)=(68.8±2.3)%, and the mass difference Δm0=m(D *)−m (D0)=(142.2±0.2)MeV/c2.
Abstract: Using the ARGUS detector at the DORIS II electron-positron storage ring at DESY, we have measured BR(D*+→D0π+)=(68.8±2.4±1.3)%, BR(D*+→D+π0)=(31.2±1.1±0.8)%, BR(D*+→D+γ)<5.2% (90%CL), BR(D*0→D0π0)=(59.6±3.5±2.8)%, and BR(D*0→D0γ)=(40.4±3.5±2.8)%, and the mass difference Δm0=m(D*0)−m(D0)=(142.2±0.3±0.2)MeV/c2.
TL;DR: In this article, the authors used ARGUS at the e+e− storage ring DORIS II at DESY to observe the decays Λc+ → Ξ−K+π+ and Λ c+ → ǫ∗0K+ and obtained evidence for the decay Ξc0 → ΛKs0.
TL;DR: It is proposed to use an artificial neural network (ANN) for the L2 trigger based on the CNAPS-1064 chip available from Adaptive Solutions, (Oregon, USA) and the intrinsic parallelism of the ANN algorithm together with the dedicated hardware offers fast processing of the trigger informations.
Abstract: Triggering at the HERA ep collider is challenging because of the high bunch crossing rate and an expected large background. In the H1 experiment, a trigger decision is made in four steps (level 1–4), stepwise decreasing the event rate and allowing for more sophisticated trigger decisions. The time available for L2 is about 20 μs. We have proposed to use an artificial neural network (ANN) for the L2 trigger based on the CNAPS-1064 chip available from Adaptive Solutions, (Oregon, USA). The intrinsic parallelism of the ANN algorithm together with the dedicated hardware offers fast processing of the trigger informations. The trigger system uses up to 10 decision units, each consisting of a Pattern Recognition Module (PRM) and a Data Distribution Board (DDB). A DDB receives the L2 data stream and generates the network inputs used by the algorithms on the PRM. A PRM is a commercial VME board carrying the CNAPS processors.
TL;DR: Using the ARGUS detector at the e+e− storage ring DORIS II at DESY, this article measured the parameters of a charmed strange meson decaying into D0K+ decaying.
Abstract: Using the ARGUS detector at the e+e− storage ring DORIS II at DESY we have measured the parameters of a charmed strange meson D*
s2
+
(2573) decaying into D0K+ The mass of this state was found to be (25745±33±16) MeV/c
2 The measured value of its width is (104±83±30) MeV and the product of the production cross section and branching ratio for this channel was determined to be (106±42
−12
+23
) pb
01 Mar 1995
TL;DR: In this paper, the parton densities in the photon have been derived from measurements of the photon structure function and of jet production in two-photon and photoproduction processes.
Abstract: The parton densities in the photon have been derived from measurements of the photon structure function and of jet production in two-photon and photoproduction processes. Recent analyses by the H1 and ZEUS collaborations show that hard photoproduction processes at HERA allow to determine the gluon density down to x values of 10−2. For a discrimination of different models the systematic uncertainties in these analyses have still to be reduced.
TL;DR: In this paper, a fast second level trigger has been developed for the ARGUS experiment which recognizes tracks originating from the interaction region, which is able to reject tracks originating in the wall of the narrow beampipe of 10.5mm radius.
Abstract: A fast second level trigger has been developed for the ARGUS experiment which recognizes tracks originating from the interaction region. The processor compares the hits in the ARGUS Micro Vertex Drift Chamber to 245760 masks stored in random access memories. The masks which are fully defined in three dimensions are able to reject tracks originating in the wall of the narrow beampipe of 10.5\,mm radius.