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  • 1. Barucca, G.
    et al.
    Makonyi, Karoly
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Preston, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per-Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wölbing, Dirk
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Zmeskal, J.
    The potential of Λ and Ξ− studies with PANDA at FAIR2021Ingår i: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 57, nr 4, artikel-id 154Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: p¯p→Λ¯Λ and p¯p→Ξ¯+Ξ−. The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.

  • 2. Barucca, G.
    et al.
    Zimmermann, I.
    Makonyi, Karoly
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Preston, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per-Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wölbing, Dirk
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Zmeskal, J.
    Feasibility studies for the measurement of time-like proton electromagnetic form factors from ̄pp→μ+μ−at PANDA at FAIR2021Ingår i: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 57, nr 1, artikel-id 30Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper reports on Monte Carlo simulation results for future measurements of the moduli of time-like proton electromagnetic form factors, vertical bar G(E)vertical bar and vertical bar G(M)vertical bar, using the (p) over barp -> mu(+)mu(-) reaction at PANDA (FAIR). The electromagnetic form factors are fundamental quantities parameterizing the electric and magnetic structure of hadrons. This work estimates the statistical and total accuracy with which the form factors can be measured at PANDA, using an analysis of simulated data within the PandaRoot software framework. The most crucial background channel is (p) over barp -> pi(+)pi(-), due to the very similar behavior of muons and pions in the detector. The suppression factors are evaluated for this and all other relevant background channels at different values of antiproton beam momentum. The signal/background separation is based on a multivariate analysis, using the Boosted Decision Trees method. An expected background subtraction is included in this study, based on realistic angular distributions of the background contribution. Systematic uncertainties are considered and the relative total uncertainties of the form factor measurements are presented.

  • 3.
    Makonyi, Karoly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Marcks von Würtemberg, Klas
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per-Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Hansen, K.
    Isaksson, L.
    Lundin, M.
    Schroder, B.
    Balkeståhl, L.
    Fransson, K.
    Johansson, T.
    Rosenbaum, C.
    Wolke, M.
    Erni, W.
    Keshelashvili, I.
    Krushe, B.
    Evaluating vacuum phototriodes designed for the PANDA electromagnetic calorimeter2014Ingår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 763, s. 36-43Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this work properties of a vacuum phototriode (VPT) and preamplifier unit designed for the electromagnetic calorimeter of the PANDA experiment being built at FAIR are investigated. With the use of lead tungstate and lanthanium bromide scintillators the VPT properties are studied at low photon energies, from tens of key in the lanthanium bromide measurements and between 10 MeV and 60 MeV in the lead tungstate measurements. At these energies the noise of the VPT unit can be expected to influence its performance significantly. It is shown that the noise contribution to the measured energy resolution, under optimal conditions, is consistent with a fluctuation of (one standard deviation) approximately 200 electrons at the VPT anode. For a lead tungstate crystal this is equivalent to a noise of 1.2 MeV. For lanthanium bromide this makes it possible to use VPTs for gamma ray spectroscopy above a few hundreds of keV without noticeable effects on the energy resolution compared to measurements with a standard photomultiplier.

  • 4.
    Makonyi, Karoly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Preston, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wölbing, Dirk
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Technical design report for the endcap disc DIRC2022Ingår i: Journal of Physics G: Nuclear and Particle Physics, ISSN 0954-3899, E-ISSN 1361-6471, Vol. 49, nr 12, artikel-id 120501Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PANDA (anti-proton annihiliation at Darmstadt) is planned to be one of the four main experiments at the future international accelerator complex FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. It is going to address fundamental questions of hadron physics and quantum chromodynamics using cooled antiproton beams with a high intensity and and momenta between 1.5 and 15 GeV/c. PANDA is designed to reach a maximum luminosity of 2 × 1032 cm−2 s. Most of the physics programs require an excellent particle identification (PID). The PID of hadronic states at the forward endcap of the target spectrometer will be done by a fast and compact Cherenkov detector that uses the detection of internally reflected Cherenkov light (DIRC) principle. It is designed to cover the polar angle range from 5° to 22° and to provide a separation power for the separation of charged pions and kaons up to 3 standard deviations (s.d.) for particle momenta up to 4 GeV/c in order to cover the important particle phase space. This document describes the technical design and the expected performance of the novel PANDA disc DIRC detector that has not been used in any other high energy physics experiment before. The performance has been studied with Monte-Carlo simulations and various beam tests at DESY and CERN. The final design meets all PANDA requirements and guarantees sufficient safety margins.

  • 5.
    Makonyi, Karoly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Preston, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wölbing, Dirk
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Technical design report for the (P)over-barANDA Barrel DIRC detector2019Ingår i: Journal of Physics G: Nuclear and Particle Physics, ISSN 0954-3899, E-ISSN 1361-6471, Vol. 46, nr 4, artikel-id 045001Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The (P) over bar ANDA (anti-Proton ANnihiliation at DArmstadt) experiment will be one of the four flagship experiments at the new international accelerator complex FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. (P) over bar ANDA will address fundamental questions of hadron physics and quantum chromodynamics using high-intensity cooled antiproton beams with momenta between 1.5 and 15 GeV/c and a design luminosity of up to 2 x 10(32) cm(-2) S-1. Excellent particle identification (PID) is crucial to the success of the (P) over bar ANDA physics program. Hadronic PID in the barrel region of the target spectrometer will be performed by a fast and compact Cherenkov counter using the detection of internally reflected Cherenkov light (DIRC) technology. It is designed to cover the polar angle range from 22 degrees to 140 degrees and will provide at least 3 standard deviations (s.d.) pi/K separation up to 3.5 GeV/c, matching the expected upper limit of the final state kaon momentum distribution from simulation. This documents describes the technical design and the expected performance of the (P) over bar ANDA Barrel DIRC detector. The design is based on the successful BaBar DIRC with several key improvements. The performance and system cost were optimized in detailed detector simulations and validated with full system prototypes using particle beams at GSI and CERN. The final design meets or exceeds the PID goal of clean pi/K separation with at least 3 s.d. over the entire phase space of charged kaons in the Barrel DIRC.

  • 6.
    Makonyi, Karoly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Preston, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per-Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wölbing, Dirk
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR2016Ingår i: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 52, nr 10, artikel-id 325Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Simulation results for future measurements of electromagnetic proton form factors at PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel (p) over barp -> e(+)e(-) is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e. (p) over barp -> pi(+)pi(-), is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance.

  • 7.
    Makonyi, Karoly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Preston, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per-Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wölbing, Dirk
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum. Stockholm Univ, Stockholm, Sweden.
    Feasibility study for the measurement of πN transition distribution amplitudes at ¯PANDA in ¯pp→J/ψπ02017Ingår i: Physical Review D: covering particles, fields, gravitation, and cosmology, ISSN 2470-0010, E-ISSN 2470-0029, Vol. 95, nr 3, artikel-id 032003Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The exclusive charmonium production process in (P) over barp annihilation with an associated pi 0 meson (p) over barp -> J/psi pi(0) is studied in the framework of QCD collinear factorization. The feasibility of measuring this reaction through the J/psi -> e(+) e(-) decay channel with the AntiProton ANnihilation at DArmstadt ((P) over bar ANDA) experiment is investigated. Simulations on signal reconstruction efficiency as well as the background rejection from various sources including the (P) over barp -> pi(+)pi(-)pi(0) and (p) over barp -> J/psi pi(0)pi(0) reactions are performed with PANDAROOT, the simulation and analysis software framework of the (P) over bar ANDA experiment. It is shown that the measurement can be done at (P) over bar ANDA with significant constraining power under the assumption of an integrated luminosity attainable in four to five months of data taking at the maximum design luminosity.

  • 8.
    Makonyi, Karoly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Preston, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per-Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wölbing, Dirk
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Study of doubly strange systems using stored antiprotons2016Ingår i: Nuclear Physics A, ISSN 0375-9474, E-ISSN 1873-1554, Vol. 954, s. 323-340Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Bound nuclear systems with two units of strangeness are still poorly known despite their importance for many strong interaction phenomena. Stored antiprotons beams in the GeV range represent an unparalleled factory for various hyperon-antihyperon pairs. Their outstanding large production probability in antiproton collisions will open the floodgates for a series of new studies of systems which contain two or even more units of strangeness at the PANDA experiment at FAIR. For the first time, high resolution gamma-spectroscopy of doubly strange Lambda Lambda-hypernuclei will be performed, thus complementing measurements of ground state decays of Lambda Lambda-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Xi(-) -atoms will be feasible and even the production of Omega(-) -atoms will be within reach. The latter might open the door to the vertical bar S vertical bar = 3 world in strangeness nuclear physics, by the study of the hadronic Omega(-) -nucleus interaction. For the first time it will be possible to study the behavior of Xi(+) in nuclear systems under well controlled conditions.

  • 9.
    Makonyi, Karoly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    von Würtemberg, Klas Marcks
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Experimental access to Transition Distribution Amplitudes with the PANDA experiment at FAIR2015Ingår i: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 51, nr 8, artikel-id 107Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Baryon-to-meson Transition Distribution Amplitudes (TDAs) encoding valuable new information on hadron structure appear as building blocks in the collinear factorized description for several types of hard exclusive reactions. In this paper, we address the possibility of accessing nucleon-to-pion (pi N) TDAs from (p) over barp -> e(+)e(-)pi(0) reaction with the future PANDA detector at the FAIR facility. At high center-of-mass energy and high invariant mass squared of the lepton pair q(2), the amplitude of the signal channel (p) over barp -> e(+)e(-)pi(0) admits a QCD factorized description in terms of pi N TDAs and nucleon Distribution Amplitudes (DAs) in the forward aid backward kinematic regimes. Assuming the validity of this factorized description, we perform feasibility studies for measuring (p) over barp -> e(+)e(-)pi(0) with the PANDA detector. Detailed simulations on signal reconstruction efficiency as well as on rejection of the most severe background channel, i.e. (p) over barp -> pi(+)pi(-)pi(0) were performed for the center-of-mass energy squared s = 5 GeV2 and s = 10 GeV2, in the kinematic regions 3.0 < q(2) < 4.3 GeV2 and 5 < q(2) < 9 GeV2, respectively, with a neutral pion scattered in the forward or backward cone vertical bar cos theta(pi 0)vertical bar > 0.5 in the proton-antiproton center-of-mass frame. Results of the simulation show that the particle identification capabilities of the PANDA detector will allow to achieve a background rejection factor of 5 . 10(7) (1 . 10(7)) at low (high) q(2) for s = 5 GeV2, and of 1 . 10(8) (6 . 10(6)) at low (high) q(2) for s = 10 GeV2, while keeping the signal reconstruction efficiency at around 40%. At both energies, a clean lepton signal can be reconstructed with the expected statistics corresponding to 2 of integrated luminosity. The cross sections obtained from the simulations are used to show that a test of QCD collinear factorization can be done at the lowest order by measuring scaling laws and angular distributions. The future measurement of the signal channel cross section with PANDA will provide a new test of the perturbative QCD description of a novel class of hard exclusive reactions and will open the possibility of experimentally accessing pi N TDAs.

  • 10.
    Makonyi, Karoly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per-Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    von Wurtemberg, K. M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Technical design report for the PANDA (AntiProton Annihilations at Darmstadt) Straw Tube Tracker2013Ingår i: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 49, nr 2, s. 25-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the PANDA target spectrometer. The STT encloses a Micro-Vertex-Detector (MVD) for the inner tracking and is followed in beam direction by a set of GEM stations. The tasks of the STT are the measurement of the particle momentum from the reconstructed trajectory and the measurement of the specific energy loss for a particle identification. Dedicated simulations with full analysis studies of certain proton-antiproton reactions, identified as being benchmark tests for the whole PANDA scientific program, have been performed to test the STT layout and performance. The results are presented, and the time lines to construct the STT are described.

  • 11.
    Makonyi, Karolyn
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Preston, Markus
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Tegnér, Per-Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wölbing, Dirk
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Precision resonance energy scans with the PANDA experiment at FAIR: Sensitivity study for width and line shape measurements of the X(3872)2019Ingår i: European Physical Journal A, ISSN 1434-6001, E-ISSN 1434-601X, Vol. 55, nr 3, artikel-id 42Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper summarises a comprehensive Monte Carlo simulation study for precision resonance energy scan measurements. Apart from the proof of principle for natural width and line shape measurements of very narrow resonances with PANDA, the achievable sensitivities are quantified for the concrete example of the charmonium-like X(3872) state discussed to be exotic, and for a larger parameter space of various assumed signal cross-sections, input widths and luminosity combinations. PANDA is the only experiment that will be able to perform precision resonance energy scans of such narrow states with quantum numbers of spin and parities that differ from JPC=1--.

1 - 11 av 11
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