16 research outputs found
Study of doubly strange systems using stored antiprotons
No full textBound 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 View the MathML sourceP‾ANDA experiment at FAIR. For the first time, high resolution γ -spectroscopy of doubly strange ΛΛ-hypernuclei will be performed, thus complementing measurements of ground state decays of ΛΛ-hypernuclei at J-PARC or possible decays of particle unstable hypernuclei in heavy ion reactions. High resolution spectroscopy of multistrange Ξ−Ξ−-atoms will be feasible and even the production of Ω−Ω−-atoms will be within reach. The latter might open the door to the |S|=3|S|=3 world in strangeness nuclear physics, by the study of the hadronic Ω−Ω−-nucleus interaction. For the first time it will be possible to study the behavior of View the MathML sourceΞ‾+ in nuclear systems under well controlled conditions
Technical design report for the Barrel DIRC detector
No full textThe (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. 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 × 1032 cm−2 s−1. Excellent particle identification (PID) is crucial to the success of the 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° to 140° and will provide at least 3 standard deviations (s.d.) π/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 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 π/K separation with at least 3 s.d. over the entire phase space of charged kaons in the Barrel DIRC
Technical Design Report for the Panda Forward Spectrometer Calorimeter
No full textThis document is devoted to the electromagnetic calorimeter of the Forward
Spectrometer and describes the design considerations, the technical layout, the
expected performance, and the production readiness
Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR
No full textThe results of simulations for future measurements of electromagnetic form factors at \PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision at which the proton form factors can be determined is estimated. The signal channel is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e. the , is studied. Furthermore, the background versus signal efficiency, statistic and systematic uncertainties on the extracted proton form factors are evaluated using to the 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 condition and detector performances.Simulation results for future measurements of electromagnetic proton form factors at ANDA (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 is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e. , 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.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 is studied on the basis of two different but consistent procedures. The suppression of the main background channel, , 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
Experimental access to Transition Distribution Amplitudes with the P̄ANDA experiment at FAIR
No full textBaryon-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
Feasibility study for the measurement of transition distribution amplitudes at ANDA in
No full textInternational audienceThe exclusive charmonium production process in p¯p annihilation with an associated π0 meson p¯p→J/ψπ0 is studied in the framework of QCD collinear factorization. The feasibility of measuring this reaction through the J/ψ→e+e- decay channel with the AntiProton ANnihilation at DArmstadt (P¯ANDA) experiment is investigated. Simulations on signal reconstruction efficiency as well as the background rejection from various sources including the p¯p→π+π-π0 and p¯p→J/ψπ0π0 reactions are performed with PandaRoot, the simulation and analysis software framework of the P¯ANDA experiment. It is shown that the measurement can be done at P¯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
Technical design report for the PANDA (AntiProton Annihilations at Darmstadt) straw tube tracker
No full textThis document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the P− ANDA 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 P− ANDA 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
Feasibility studies of time-like proton electromagnetic form factors at P ¯ ANDA at FAIR
No full textAbstract. 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 ¯pp → e+e − is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e. ¯pp → π+π−, 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
Feasibility studies of the time-like proton electromagnetic form factor measurements with PANDA at FAIR
No full text12 pages, 4 tables, 8 figuresThe possibility of measuring the proton electromagnetic form factors in the time-like region at FAIR with the \PANDA detector is discussed. Detailed simulations on signal efficiency for the annihilation of into a lepton pair as well as for the most important background channels have been performed. It is shown that precision measurements of the differential cross section of the reaction can be obtained in a wide angular and kinematical range. The individual determination of the moduli of the electric and magnetic proton form factors will be possible up to a value of momentum transfer squared of (GeV/c). The total cross section will be measured up to (GeV/c). The results obtained from simulated events are compared to the existing data. Sensitivity to the two photons exchange mechanism is also investigated
Experimental access to Transition Distribution Amplitudes with the P̄ANDA experiment at FAIR
No full textBaryon-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 (N) TDAs from ¯pp ! e+e−0 reaction with the future ¯ PANDA detector at the FAIR facility. At high center of mass energy and high invariant mass of the lepton pair q2, the amplitude of the signal channel ¯pp ! e+e−0 admits a QCD factorized description in terms of N TDAs and nucleon Distribution Amplitudes (DAs) in the forward and backward kinematic regimes. Assuming the validity of this factorized description, we perform feasibility studies for measuring ¯pp ! e+e−0 with the ¯ PANDA detector. Detailed simulations on signal reconstruction efficiency as well as on rejection of the most severe background channel, i.e. ¯pp ! +−0 were performed for the center of mass energy squared s = 5 GeV2 and s = 10 GeV2, in the kinematic regions 3.0 < q2 < 4.3 GeV2 and 5 < q2 < 9 GeV2, respectively, with a neutral pion scattered in the forward or backward cone | cos 0 | > 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 · 107 (1 · 107) at low (high) q2 for s = 5 GeV2, and of 1 · 108 (6 · 106) at low (high) q2 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 fb−1 of integrated luminosity. The future measurement of the signal channel cross section with ¯ PANDA will provide a new test of perturbative QCD description of a novel class of hard exclusive reactions and will open the possibility of experimentally accessing N TDAs
