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1.	Bouyoucef, S E, et al. (author) Poster Session 2 : Monday 4 May 2015, 08 2015 In: European Heart Journal Cardiovascular Imaging. - : Oxford University Press (OUP). - 2047-2404 .- 2047-2412. ; 16 Suppl 1 Journal article (peer-reviewed)
2.	Bargholtz, Chr., et al. (author) The WASA detector facility at CELSIUS 2008 In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 594:3, s. 339-350 Journal article (peer-reviewed)abstract The WASA 4 pi multidetector system, aimed at investigating light meson production in light ion collisions and eta meson rare decays at the CELSIUS storage ring in Uppsala is presented. A unique feature of the system is the use of hydrogen pellets as internal targets for the first time. A detailed description of the design, together with the anticipated and achieved performance parameters are given. (C) 2008 Elsevier B.V. All rights reserved.
3.	Guidoboni, G., et al. (author) How to Reach a Thousand-Second in-Plane Polarization Lifetime with 0.97-GeV/c Deuterons in a Storage Ring 2016 In: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 117:5 Journal article (peer-reviewed)abstract We observe a deuteron beam polarization lifetime near 1000 s in the horizontal plane of a magnetic storage ring (COSY). This long spin coherence time is maintained through a combination of beam bunching, electron cooling, sextupole field corrections, and the suppression of collective effects through beam current limits. This record lifetime is required for a storage ring search for an intrinsic electric dipole moment on the deuteron at a statistical sensitivity level approaching 10(-29) e cm.
4.	Eversmann, D., et al. (author) New Method for a Continuous Determination of the Spin Tune in Storage Rings and Implications for Precision Experiments 2015 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 115:9 Journal article (peer-reviewed)abstract A new method to determine the spin tune is described and tested. In an ideal planar magnetic ring, the spin tune-defined as the number of spin precessions per turn-is given by nu(s) = gamma G (gamma is the Lorentz factor, G the gyromagnetic anomaly). At 970 MeV/c, the deuteron spins coherently process at a frequency of approximate to 120 kHz in the Cooler Synchrotron COSY. The spin tune is deduced from the up-down asymmetry of deuteron-carbon scattering. In a time interval of 2.6 s, the spin tune was determined with a precision of the order 10(-8), and to 1 x 10(-10) for a continuous 100 s accelerator cycle. This renders the presented method a new precision tool for accelerator physics; controlling the spin motion of particles to high precision is mandatory, in particular, for the measurement of electric dipole moments of charged particles in a storage ring.
5.	Keleta, S, et al. (author) Exclusive measurement of two-pion production in the dd -> He-4 pi pi reaction 2009 In: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 825:1-2, s. 71-90 Journal article (peer-reviewed)abstract The results from the first kinematically complete measurement of the dd -> He-4 pi pi reaction are reported. The aim was to investigate a long standing puzzle regarding the origin of the peculiar pi pi-invariant mass distributions appearing in double pion production in light ion collisions, the so-called ABC effect. The measurements were performed at the incident deuteron energies of 712 MeV and 1029 MeV. with the WASA detector assembly at CELSIUS in Uppsala, Sweden. We report the observation of a characteristic enhancement at low pi pi-invariant mass at 712 MeV, the lowest energy yet. At the higher energy, in addition to confirming previous experimental observations, Our results reveal a strong angular dependence of the pions in the overall centre of mass system. The results are qualitatively reproduced by a theoretical model, according to which the ABC effect is described as resulting from a kinematical enhancement in the production of the pion pairs from two parallel and independent NN -> d pi sub-processes. (C) 2009 Elsevier B.V. All rights reserved.
6.	Kren, F., et al. (author) Exclusive measurements of pp -> d pi(+)pi(0) : Double-pionic fusion without ABC effect 2010 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 684:2-3, s. 110-113 Journal article (peer-reviewed)abstract Exclusive measurements of the reaction pp -> d pi(+)pi(0) have been carried out at T-p = 1.1 GeV at the CELSIUS storage ring using the WASA detector. The isovector pi(+)pi(0) channel exhibits no enhancement at low invariant pi pi masses, i.e. no ABC effect. Therefore this most basic isovector double-pionic fusion reaction qualifies as an ideal test case for the conventional t-channel Delta Delta excitation process. Indeed, the obtained differential distributions reveal the conventional t-channel Delta Delta mechanism as the appropriate reaction process, which also accounts for the observed energy dependence of the total cross section.
7.	Schönning, Karin, et al. (author) Polarisation of the omega meson in the pd -> He-3 omega reaction at 1360 and 1450 MeV 2008 In: Physics Letters B. - elsevier : Elsevier BV. - 0370-2693 .- 1873-2445. ; 668:4, s. 258-262 Journal article (peer-reviewed)abstract The tensor polarisation of omega mesons produced in the pd -> He-3 omega reaction has been studied at two energies near threshold. The 3 He nuclei were detected in coincidence with the pi(0)pi(+)pi(-) or pi(0)gamma decay products of the omega. in contrast to the case of phi-meson production, the omega mesons are found to be unpolarised. This brings into question the applicability of the Okubo-Zweig-lizuka rule when comparing the production of vector mesons in low energy hadronic reactions.
8.	Schönning, Karin, et al. (author) Production of the omega meson in the pd -> He-3 omega reaction at 1450 MeV and 1360 MeV 2009 In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 79:4, s. 044002- Journal article (peer-reviewed)abstract The production of omega mesons in the pd -> He-3 omega reaction has been studied at two energies near the kinematic threshold, T-p = 1450 MeV and T-p = 1360 MeV. The differential cross section was measured as a function of the omega c.m. angle at both energies over the whole angular range. Whereas the results at 1360 MeV are consistent with isotropy, strong rises are observed near both the forward and backward directions at 1450 MeV. Calculations made using a two-step model with an intermediate pion fail to reproduce the shapes of the measured angular distributions and also underestimate the total cross sections.
9.	Bargholtz, Chr., et al. (author) Measurement of the eta -> pi(+)pi(-)e(+)e(-) decay branching ratio 2007 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 644:5-6, s. 299-303 Journal article (peer-reviewed)abstract The reaction pd -> He-3 eta at threshold was used to provide a clean source of eta mesons for decay studies with the WASA detector at CELSIUS. The branching ratio of the decay eta -> pi(+)pi(-)e(+)e(-) is measured to be (4.3 +/- 1.3 +/- 0.4) x 10(-4).
10.	Bashkanov, M., et al. (author) Double-Pionic Fusion of Nuclear Systems and the "ABC" Effect : Approaching a Puzzle by Exclusive and Kinematically Complete Measurements 2009 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 102:5, s. 052301- Journal article (peer-reviewed)abstract The ABC effect-a puzzling low-mass enhancement in the pi pi invariant mass spectrum, first observed by Abashian, Booth, and Crowe-is well known from inclusive measurements of two-pion production in nuclear fusion reactions. Here we report on the first exclusive and kinematically complete measurements of the most basic double-pionic fusion reaction pn -> d pi(0)pi(0) at beam energies of 1.03 and 1.35 GeV. The measurements, which have been carried out at CELSIUS-WASA, reveal the ABC effect to be a (pi pi)(I=L=0) channel phenomenon associated with both a resonancelike energy dependence in the integral cross section and the formation of a Delta Delta system in the intermediate state. A corresponding simple s-channel resonance ansatz provides a surprisingly good description of the data.
11.	Bashkanov, M., et al. (author) Exclusive measurements of pd -> He-3 pi pi : The ABC effect revisited 2006 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 637:4-5, s. 223-228 Journal article (peer-reviewed)abstract Exclusive measurements of the reactions pd -> He-3 pi(+)7 pi(-) and pd -> He-3 pi(0)pi(0) have been carried out at T-p = 0.893 GeV at the CELSIUS storage ring using the WASA detector. The pi(+)pi(-) channel evidences a pronounced enhancement at low invariant pi pi masses-as anticipated from previous inclusive measurements of the ABC effect. This enhancement is seen to be even much larger in the isoscalar pi(0)pi(0) channel. The differential distributions prove this enhancement to be of scalar-isoscalar nature. Delta Delta calculations give a good description of the data, if a boundstate condition is imposed for the intermediate Delta Delta system.
12.	Bashkanov, M., et al. (author) Measurement of the slope parameter for the η → 3π0 decay in the pp → ppη reaction 2007 In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 76:4, s. 048201- Journal article (peer-reviewed)abstract The CELSIUS-WASA setup is used to measure the 3π0 decay of η mesons produced in pp interactions with beam kinetic energies of 1.36 and 1.45 GeV. The efficiency-corrected Dalitz plot and density distributions for this decay are shown, together with a fit of the quadratic slope parameter α yielding α = −0.026 ± 0.010(stat) ± 0.010(syst). This value is compared to recent experimental results and theoretical predictions.
13.	Berlowski, M., et al. (author) Measurement of eta meson decays into lepton-antilepton pairs 2008 In: Physical Review D. Particles and fields. - : American Physical Society. - 0556-2821 .- 1089-4918. ; 77:3, s. 032004- Journal article (peer-reviewed)abstract A search for rare lepton decays of the eta meson was performed using the WASA detector at CELSIUS. Two candidates for double Dalitz decay eta -> e(+)e(-)e(+)e(-) events are reported with a background of 1.3 +/- 0.2 events. This allows to set an upper limit to the branching ratio of 9.7x10(-5) (90% CL). The branching ratio for the decay eta -> e(+)e(-)gamma is determined to (7.8 +/- 0.5(stat)+/- 0.8(syst))x10(-3) in agreement with world average value. An upper limit (90% CL) for the branching ratio for the eta -> e(+)e(-) decay is 2.7x10(-5) and a limit for the sum of the eta ->mu(+)mu(-)mu(+)mu(-) and eta ->pi(+)pi(-)mu(+)mu(-) decays is 3.6x10(-4).
14.	Hempelmann, N., et al. (author) Locking the Spin Precession in a Storage Ring 2017 In: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 119:1 Journal article (peer-reviewed)abstract This Letter reports the successful use of feedback from a spin polarization measurement to the revolution frequency of a 0.97 GeV= c bunched and polarized deuteron beam in the Cooler Synchrotron (COSY) storage ring in order to control both the precession rate (approximate to 121 kHz) and the phase of the horizontal polarization component. Real time synchronization with a radio frequency (rf) solenoid made possible the rotation of the polarization out of the horizontal plane, yielding a demonstration of the feedback method to manipulate the polarization. In particular, the rotation rate shows a sinusoidal function of the horizontal polarization phase (relative to the rf solenoid), which was controlled to within a 1 standard deviation range of sigma= 0.21 rad. The minimum possible adjustment was 3.7 mHz out of a revolution frequency of 753 kHz, which changes the precession rate by 26 mrad/s. Such a capability meets a requirement for the use of storage rings to look for an intrinsic electric dipole moment of charged particles.
15.	Kren, F., et al. (author) THE pp -> d pi(+)pi(0) REACTION - A CASE OF Delta Delta EXCITATION WITHOUT ABC-EFFECT 2009 In: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 24:2-3, s. 561-563 Journal article (peer-reviewed)abstract The ABC effect, a low-mass enhancement in the invariant pp mass, is observed in double-pionic fusion reactions leading to a bound nuclear system in the final state. From previous measurements there have been indications that this phenomenon is resctricted to the sigma channel of the pp system. With exclusive measurements of the pp -> d pi(+)pi(0) reaction at T-p = 1.1 GeV we demonstrate that, indeed, the ABC effect does not occur in the vector-isovector Delta Delta channel (rho channel) despite the fact that the Delta Delta excitation is oberved to be the dominant reaction process. We also show that this reaction is well described by a t-channel Delta Delta excitation with the subsequent decay into the vector-isovector Delta Delta channel given by the rho channel operator.
16.	Oellers, D., et al. (author) Polarizing a stored proton beam by spin flip? 2009 In: Physics Letters B. - : Elsevier. - 0370-2693 .- 1873-2445. ; 674:4-5, s. 269-275 Journal article (peer-reviewed)abstract We discuss polarizing a proton beam in a storage ring, either by selective removal or by spin flip of the stored ions. Prompted by recent, conflicting calculations, we have carried out a measurement of the spin-flip cross section in low-energy electron–proton scattering. The experiment uses the cooling electron beam at COSY as an electron target. The measured cross sections are too small for making spin flip a viable tool in polarizing a stored beam. This invalidates a recent proposal to use co-moving polarized positrons to polarize a stored antiproton beam.
17.	Pauly, C., et al. (author) The pp→ppπππ reaction channels in the threshold region 2007 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 649:2-3, s. 122-127 Journal article (peer-reviewed)abstract The cross section for direct neutral and charged three pion production in pp interactions was measured at excess energies in the range 160–216 MeV. That comprises the first measurement of the pp→ppπ0π0π0 reaction and the direct comparison with the pp→ppπ+π−π0 process. The experiment was performed above the η meson production threshold and the cross section could be directly normalized to the cross section of the pp→ppη reaction, with the η decaying into 3 pions. Since the same final states are selected, the measurement has a low systematical error. The measured cross section ratio σ(pp→ppπ+π−π0)/σ(pp→ppπ0π0π0) is compared to predictions of dominance of different isobars in the intermediate state.
18.	Pettersson, Henrik, et al. (author) eta PRODUCTION IN PROTON-PROTON COLLISIONS AT 72 MeV EXCESS ENERGY 2009 In: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 24:2-3, s. 446-449 Journal article (peer-reviewed)abstract The production of eta mesons at an excess energy of 72 MeV has been studied in the reaction pp -> pp(eta)gamma gamma. It is shown that a simple model with Pp. final states included reproduces observed differential distributions better than the same model restricted to Ss, Sd and Ds final states. The strong influence of the Pp states could be taken as an indication of rho dominance within an one boson exchange model for the excitation of N*(1535).
19.	Schonning, K., et al. (author) The pd -> He-3 eta pi(0) reaction at T-p=1450 MeV CELSIUS/WASA Collaboration 2010 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 685:1, s. 33-37 Journal article (peer-reviewed)abstract The cross section for the pd -> He-3 eta pi(0) reaction has been measured at a beam energy of 1450 MeV using the WASA detector at the CELSIUS storage ring. The He-3 was detected in coincidence with four photons from the decays of the two mesons. The data indicate that the production mechanism involves the formation of the Delta(1232) isobar. Although the beam energy does not allow the full peak of this resonance to be seen, the invariant mass distributions Of all three pairs of final particles are well reproduced by a phase space Monte Carlo simulation weighted with the p-wave factor of the square of the pi(0) momentum in the He-3 pi(0) system.
20.	Schönning, Karin, et al. (author) Production of eta and 3 pi mesons in the pd -> (HeX)-He-3 reaction at 1360 and 1450 MeV 2010 In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 45:1, s. 11-21 Journal article (peer-reviewed)abstract The cross-sections of the pd -> He-3 eta, pd -> He-3 pi(0)pi(0)pi(0) and pd -> He-3 pi(+)pi(-)pi(0) reactions have been measured at the beam kinetic energies T-p = 1360 MeV and T-p = 1450 MeV using the CELSIUS/WASA detector setup. At both energies, the differential cross-section d sigma/d Omega of the eta meson in the pd -> He-3 eta reaction shows a strong forward-backward asymmetry in the CMS. The ratio between the pd -> He-3 pi(+)pi(-)pi(0) and pd -> He-3 pi(0)pi(0)pi(0) cross-sections has been analysed in terms of isospin amplitudes. The reconstructed invariant-mass distributions of the pi pi, He-3 pi and (3)He2 pi systems provide hints on the role of nucleon resonances in the 3 pi production process.
21.	Skorodko, T., et al. (author) Exclusive measurement of the pp -> nn pi(+)pi(+) reaction at 1.1 GeV 2011 In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 47:9, s. 108- Journal article (peer-reviewed)abstract First exclusive data for the pp -> nnp(+)pi(+) reaction have been obtained at CELSIUS with the WASA detector setup at a beam energy of T(p) - 1.1 GeV. Total and differential cross-sections disagree with theoretical calculations, which predict the Delta Delta excitation to be the dominant process at this beam energy. Instead, the data require the excitation of one of the nucleons to a higher-lying Delta state, preferably the Delta(1600)P(33), to be the leading process.
22.	Skorodko, T., et al. (author) ISOSPIN DECOMPOSITION OF pp -> NN pi pi CROSS SECTIONS : DO WE SEE A SIGN OF Delta(1600) EXCITATION IN THE nn pi(+)pi(+) CHANNEL? 2009 In: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 24:2-3, s. 450-453 Journal article (peer-reviewed)abstract The two-pion production in pp-collisions has been investigated in exclusive measurements from threshold up to T-p = 1.36 GeV. Total and differential cross sections have been obtained for the channels pn pi(+) pi(0), pp pi(+) pi(-), pp pi(0)pi(0) and also nn pi(+)pi(+). For intermediate incident energies T-p > 1 GeV, i.e. in the region, which is beyond the Roper excitation but at the onset of Delta Delta excitation the total pp pi(0)pi(0) cross section falls behind theoretical predictions by as much as an order of magnitude near 1.2 GeV, whereas the nn pi(+)pi(+) cross section is a factor of five larger than predicted. A model-unconstrained isospin decompostion of the cross section points to a significant contribution of an isospin 3/2 resonance other than the Delta(1232). As a possible candidate the Delta(1600) is discussed.
23.	Skorodko, T, et al. (author) Two-pion production in proton-proton collisions : experimental total cross sections and their isospin decomposition 2009 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 679:1, s. 30-35 Journal article (peer-reviewed)abstract The two-pion production in pp-collisions has been investigated at CELSIUS in exclusive measurements from threshold up to T-P = 1.36 GeV. Total and differential Cross sections have been obtained for the channels pn pi(+)pi(0), pp pi(+)pi(-), pp pi(0)pi(0) and also nn pi(+)pi(+). For intermediate incident energies T-P > 1GeV, i.e. in the region which is beyond the Roper excitation but at the onset of Delta Delta excitation, the total pp pi(0)pi(0) cross section falls behind theoretical predictions by as much as all order of magnitude near 1.2 GeV, whereas the nn pi(+)pi(+) cross section is a factor of five larger than predicted. An isospin decomposition of the total cross sections exhibits a s-channel-like energy dependence in the region of the Roper excitation as well as a significant contribution of an isospin 3/2 resonance other than the Delta(1232). As possible candidates the Delta(1600) and the Delta(1700) are discussed. (C) 2009 Elsevier B.V. All rights reserved.
24.	Thörngren Engblom, Pia, et al. (author) Experimental search for evidence of the three-nucleon force and a new analysis method 2004 In: FEW-BODY PROBLEMS IN PHYSICS. - : AIP. - 0735402531 ; , s. 65-68 Conference paper (other academic/artistic)abstract A research program with the aim of investigating the spin dependence of the three-nucleon continuum in pd collisions at intermediate energies was carried out at IUCF using the Polarized INternal Target EXperiments (PINTEX) facility. In the elastic scattering experiment at 135 and 200 MeV proton beam energies a total of 15 independent spin observables were obtained. The breakup experiment was done with a vector and tensor polarized beam of 270 MeV and an internal polarized hydrogen gas target. We developed a novel technique for the analysis of the breakup observables, the sampling method. The new approach takes into account acceptance and non-uniformities of detection efficiencies and is suitable for any kinematically complete experiment with three particles in the final state.
25.	Augustyniak, W., et al. (author) Polarization of a stored beam by spin-filtering 2012 In: Physics Letters B. - : Elsevier. - 0370-2693 .- 1873-2445. ; 718:1, s. 64-69 Journal article (peer-reviewed)abstract The PAX Collaboration has successfully performed a spin-filtering experiment with protons at the COSY-ring. The measurement allowed the determination of the spin-dependent polarizing cross section, that compares well with the theoretical prediction from the nucleon-nucleon potential. The test confirms that spin-filtering can be adopted as a method to polarize a stored beam and that the present interpretation of the mechanism in terms of the proton-proton interaction is correct. The outcome of the experiment is of utmost importance in view of the possible application of the method to polarize a beam of stored antiprotons.
26.	Bilger, Ralph, et al. (author) Measurement of the pd -> pd eta Cross Section in Complete Kinematics 2004 In: Phys. Rev.. ; C69, s. 014003- Journal article (peer-reviewed)
27.	Classon, J, et al. (author) Prostate cancer disease recurrence after radical prostatectomy is associated with HLA type and local cytomegalovirus immunity 2022 In: Molecular oncology. - : Wiley. - 1878-0261 .- 1574-7891. ; 16:19, s. 3452-3464 Journal article (peer-reviewed)
28.	Guidoboni, G., et al. (author) Connection between zero chromaticity and long in-plane polarization lifetime in a magnetic storage ring 2018 In: Physical Review Accelerators and Beams. - : American Physical Society. - 2469-9888. ; 21:2 Journal article (peer-reviewed)abstract In this paper, we demonstrate the connection between a magnetic storage ring with additional sextupole fields set so that the x and y chromaticities vanish and the maximizing of the lifetime of in-plane polarization (IPP) for a 0.97-GeV/c deuteron beam. The IPP magnitude was measured by continuously monitoring the down-up scattering asymmetry (sensitive to sideways polarization) in an in-beam, carbontarget polarimeter and unfolding the precession of the IPP due to the magnetic anomaly of the deuteron. The optimum operating conditions for a long IPP lifetime were made by scanning the field of the storage ring sextupole magnet families while observing the rate of IPP loss during storage of the beam. The beam was bunched and electron cooled. The IPP losses appear to arise from the change of the orbit circumference, and consequently the particle speed and spin tune, due to the transverse betatron oscillations of individual particles in the beam. The effects of these changes are canceled by an appropriate sextupole field setting.
29.	Hempelmann, N., et al. (author) Phase measurement for driven spin oscillations in a storage ring 2018 In: Physical Review Accelerators and Beams. - : American Physical Society. - 2469-9888. ; 21:4 Journal article (peer-reviewed)abstract This paper reports the first simultaneous measurement of the horizontal and vertical components of the polarization vector in a storage ring under the influence of a radio frequency (rf) solenoid. The experiments were performed at the Cooler Synchrotron COSY in Julich using a vector polarized, bunched 0.97 GeV/c deuteron beam. Using the new spin feedback system, we set the initial phase difference between the solenoid field and the precession of the polarization vector to a predefined value. The feedback system was then switched off, allowing the phase difference to change over time, and the solenoid was switched on to rotate the polarization vector. We observed an oscillation of the vertical polarization component and the phase difference. The oscillations can be described using an analytical model. The results of this experiment also apply to other rf devices with horizontal magnetic fields, such as Wien filters. The precise manipulation of particle spins in storage rings is a prerequisite for measuring the electric dipole moment (EDM) of charged particles.
30.	Kuros-Zolnierczuk, J., et al. (author) Faddeev Calculations of Breakup Reactions with Realistic Experimental Constraints 2004 In: Few-Body Systems. - : Springer Science and Business Media LLC. - 0177-7963 .- 1432-5411. ; 34, s. 259-273 Journal article (peer-reviewed)abstract We present a method to integrate predictions from a theoretical model of a reaction with three bodies in the final state over the region of phase space covered by a given experiment. The method takes into account the true experimental acceptance, as well as variations of detector efficiency, and eliminates the need for a Monte-Carlo simulation of the detector setup. The method is applicable to kinematically complete experiments. Examples of the use of this method include sveral polarization observables in dp breakup at 270 MeV. The calculations are carried out in the Faddeev framework with the CD Bonn nucleon-nucleon interaction, with or without the inclusion of an additional three-nucleon force.
31.	Kurt, S, et al. (author) CopyVAE: a variational autoencoder-based approach for copy number variation inference using single-cell transcriptomics 2024 In: Bioinformatics (Oxford, England). - 1367-4811. ; 40:5 Journal article (peer-reviewed)
32.	Meyer, H.O., et al. (author) Axial observables in d-->p--> breakup and the three-nucleon force. : PINTEX Collaboration 2004 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 93:11, s. 112502- Journal article (peer-reviewed)
33.	Saleev, A., et al. (author) Spin tune mapping as a novel tool to probe the spin dynamics in storage rings 2017 In: Physical Review Accelerators and Beams. - : American Physical Society. - 2469-9888. ; 20:7 Journal article (peer-reviewed)abstract Precision experiments, such as the search for electric dipole moments of charged particles using storage rings, demand for an understanding of the spin dynamics with unprecedented accuracy. The ultimate aim is to measure the electric dipole moments with a sensitivity up to 15 orders in magnitude better than the magnetic dipole moment of the stored particles. This formidable task requires an understanding of the background to the signal of the electric dipole from rotations of the spins in the spurious magnetic fields of a storage ring. One of the observables, especially sensitive to the imperfection magnetic fields in the ring is the angular orientation of stable spin axis. Up to now, the stable spin axis has never been determined experimentally, and in addition, the JEDI collaboration for the first time succeeded to quantify the background signals that stem from false rotations of the magnetic dipole moments in the horizontal and longitudinal imperfection magnetic fields of the storage ring. To this end, we developed a new method based on the spin tune response of a machine to artificially applied longitudinal magnetic fields. This novel technique, called spin tune mapping, emerges as a very powerful tool to probe the spin dynamics in storage rings. The technique was experimentally tested in 2014 using polarized deuterons stored in the cooler synchrotron COSY, and for the first time, the angular orientation of the stable spin axis at two different locations in the ring has been determined to an unprecedented accuracy of better than 2.8 mu rad.
34.	Schönning, Karin, et al. (author) The pd →3Heηπ0 reaction at Tp = 1450 MeV 2010 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 685:1, s. 33-37 Journal article (peer-reviewed)abstract The cross section for the pd→3Heηπ0 reaction has been measured at a beam energy of 1450 MeV using the WASA detector at the CELSIUS storage ring and detecting one 3He and four photons from the decays of the two mesons. The data indicate that the production mechanism involves the formation of the Δ(1232) isobar. Although the beam energy does not allow the full peak of this resonance to be seen, the invariant masses of all three pairs of final particles are well reproduce dby a phase space Monte Carlo simulation weighted with the p-wave factor of the square of the π0 momentum in the 3He π0 system.
35.	Skorodko, T., et al. (author) Delta Delta excitation in proton-proton induced pi(0)pi(0) production 2011 In: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 695:1-4, s. 115-123 Journal article (peer-reviewed)abstract Exclusive measurements of the pp -> pp pi(0)pi(0) reaction have been performed at CELSIUS/WASA at energies from threshold up to T-p = 1.3 GeV. Total and differential cross sections have been obtained. Here we concentrate on energies T-p >= GeV. where the Delta Delta excitation becomes the leading process. No evidence is found for a significant ABC effect beyond that given by the conventional t-channel Delta Delta excitation. This holds also for the double-pionic fusion to the quasibound He-2. The data are compared to model predictions, which are based on both pi- and rho-exchange. Total and differential cross sections are at variance with these predictions and call for a profound modification of the rho-exchange. A phenomenological modification allowing only a small rho-exchange contribution leads to a quantitative description of the data.
36.	Skorodko, T., et al. (author) Excitation of the Roper resonance in single- and double-pion production in nucleon-nucleon collisions 2008 In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 35:3, s. 317-319 Journal article (peer-reviewed)abstract In most investigations the Roper resonance is sensed only very indirectly via complex partial-wave analyses. We find indications for its excitation in the invariant n pi(+) mass spectrum of the pp -> np pi(+) reaction at M approximate to 1360 MeV with a width of approximate to 150 MeV . The values fit very favorably to the most recent phase shift results as well as to the observations at BES. In the near-threshold two-pion production pp -> pp pi(0)pi(0) , where the Roper excitation and its subsequent decays via the routes N* -> Delta pi -> N pi pi and N* -> N sigma are the only dominant processes, we find its direct decay into the N sigma channel to be the by far dominating decay process -in favor of a monopole excitation of the Roper resonance.
37.	Skorodko, T., et al. (author) THE pp -> pp pi(0)pi(0) REACTION AND ITS LIMITING CASE, FUSION TO QUASI-BOUND He-2, IN SEARCH OF THE ABC EFFECT 2011 In: International Journal of Modern Physics A. - 0217-751X .- 1793-656X. ; 26:3-4, s. 702-704 Journal article (peer-reviewed)abstract The pi(0)pi(0) production in pp-collisions has been investigated in exclusive and kinematically complete measurements from threshold up to T-p = 1.4 GeV. For incident energies T-p > 1 GeV, i.e. in the region beyond the Roper excitation, the Delta Delta excitation process takes over. The data are well explained by the t-channel Delta Delta process dominated by pion exchange. There is no low-mass enhancement (ABC effect) in the pi(0)pi(0)-invariant mass distribution beyond that given by the conventional t-channel Delta Delta process. This is also true for the limiting case, where the protons are in the quasi-bound He-2 state.
38.	v. Przewoski, B., et al. (author) Analyzing powers and spin correlation coefficients for p+d elastic scattering at 135 and 200 MeV 2006 In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 74:6 Journal article (peer-reviewed)abstract The proton and deuteron analyzing powers and ten of the possible 12 spin correlation coefficients have been measured for p+d elastic scattering at proton bombarding energies of 135 and 200 MeV. The results are compared with Faddeev calculations using two different NN potentials. The qualitative features of the extensive data set on the spin dependence in p+d elastic scattering over a wide range of angles presented here are remarkably well explained by two-nucleon force predictions without inclusion of a three-nucleon force. The remaining discrepancies are, in general, not alleviated when theoretical three-nucleon forces are included in the calculations.
39.	Andersson, M, et al. (author) Isospin resolved double pion production in the reaction p+d -> He-3+2 pi 2000 In: PHYSICS LETTERS B. - : ELSEVIER SCIENCE BV. - 0370-2693. ; 485:4, s. 327-333 Journal article (peer-reviewed)abstract Neutral and charged two-pion production in p + d --> He-3 + 2 pi reactions has been studied at CELSIUS at a proton beam energy of 477 MeV. The total cross section for double pion production is 0.22 +/- 0.03 mu b. The ratio of the cross sections for the pr
40.	Andersson, M, et al. (author) The exclusive p plus d -> He-3+2 pi reaction at CELSIUS 2000 In: ACTA PHYSICA POLONICA B. - : ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS. ; , s. 2123-2126 Conference paper (peer-reviewed)abstract Neutral and charged two-pion production in p + d --> He-3 --> 2 pi reactions has been studied at a proton beam energy of 477 MeV. The total cross section for double pion production is 0.22 +/- 0.03 mub. The ratio of the cross sections for the production o
41.	Carnicky, J., et al. (author) Estimation of area at risk in myocardial infarction 2007 In: Computers in Cardiology 2007, CAR 2007. - 9781424425334 ; 34, s. 169-172 Conference paper (peer-reviewed)abstract This study presents a new method for estimation and imaging of the area at risk (AaR) in myocardial infarction (MI). The values of the ST-segment deviations of 12-lead ECG signal were used as input parameters. Based on DECARTO model, the spherical surface was chosen as a reference surface to approximate the ventricular wall. On this surface, the spatial ST vector was projected. The center of AaR was defined as an intersection of the spatial ST vector with spherical surface; the size of the AaR was set to be proportional to the number of electrical leads with ST- segment deviations. The method was tested using data of 10 patients with acute MI. The visual comparison showed good agreement with the AaRECG estimates based originally on the Selvester QRS scoring as well as with a non- electrocardiographic imaging method (SPECT).
42.	Engblom, J, et al. (author) Towards Industry-Strength Worst-Case Execution Time Analysis 1999 Reports (other academic/artistic)
43.	Foster, J E, et al. (author) Determination of left ventricular long-axis orientation using MRI: changes during the respiratory and cardiac cycles in normal and diseased subjects 2005 In: Clinical Physiology and Functional Imaging. - 1475-0961. ; 25:5, s. 286-292 Journal article (peer-reviewed)abstract Background: It has previously been shown that magnetic resonance imaging (MRI) can be used to accurately determine left ventricular (LV) long-axis orientation in healthy individuals. However, the inter- and intra-observer variability in patients with acute coronary syndrome (ACS) and chronic heart failure (CHF) has not been explored. Furthermore, the changes in LV long-axis orientation because of respiration and during the cardiac cycle remain to be determined. Methods: LV long-axis orientation was determined by MRI in the frontal and transverse planes in 44 subjects with no cardiac disease, 20 ACS patients and 13 CHF patients. Changes in LV long-axis orientation because of respiration were assessed in a subset of 25 subjects. Changes during the cardiac cycle were assessed in six subjects from each subject group. Reproducibility was assessed by a re-examination of 17 subjects after 28 days. Results: The inter- and intra-observer variability for LV long-axis orientation was low for all subject groups. The difference between the baseline and the 28 days examinations was -1.4 +/- 5.9 degrees and -0.8 +/- 4.4 degrees in the frontal and transverse planes, respectively. No significant change in LV long-axis orientation was found between end-expiration and end-inspiration (frontal plane, P = 0.63 and transverse plane, P = 0.42; n = 25). No significant difference in change of the LV long-axis orientation during the cardiac cycle was found between the subject groups (frontal plane, chi-square 1.8, P = 0.40 and transverse plane, chi-square 5.7, P = 0.06). Conclusions: There is a low inter-and intra-observer variability and a high reproducibility for determining LV long-axis orientation in patients with no cardiac disease as well as in patients with ACS or CHF. There is no significant change in LV long-axis orientation due to respiration, and only small changes during the cardiac cycle in these groups.
44.	Meyer, H.O, et al. (author) Complete set of polarization observables in (pol)p(pol)p->pp pi0 clos to threshold 2001 In: Phys. Rev. C. - : The American Physical Society. ; 63:6, s. 064002-1 Journal article (peer-reviewed)abstract In a kinematically complete experiment we have measured the two analyzing powers and the five spin correlation coefficients of the reaction (pol)p pol(p) -> p p pi0 as a function of all five parameters of the three-body final state for bombarding energies
45.	Nickander, J, et al. (author) Stress native T1 and native T2 mapping compared to myocardial perfusion reserve in long-term follow-up of severe Covid-19 2023 In: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 13:1, s. 4159- Journal article (peer-reviewed)abstract Severe Covid-19 may cause a cascade of cardiovascular complications beyond viral pneumonia. The severe inflammation may affect the microcirculation which can be assessed by cardiovascular magnetic resonance (CMR) imaging using quantitative perfusion mapping and calculation of myocardial perfusion reserve (MPR). Furthermore, native T1 and T2 mapping have previously been shown to identify changes in myocardial perfusion by the change in native T1 and T2 during adenosine stress. However, the relationship between native T1, native T2, ΔT1 and ΔT2 with myocardial perfusion and MPR during long-term follow-up in severe Covid-19 is currently unknown. Therefore, patients with severe Covid-19 (n = 37, median age 57 years, 24% females) underwent 1.5 T CMR median 292 days following discharge. Quantitative myocardial perfusion (ml/min/g), and native T1 and T2 maps were acquired during adenosine stress, and rest, respectively. Both native T1 (R2 = 0.35, p < 0.001) and native T2 (R2 = 0.28, p < 0.001) correlated with myocardial perfusion. However, there was no correlation with ΔT1 or ΔT2 with MPR, respectively (p > 0.05 for both). Native T1 and native T2 correlate with myocardial perfusion during adenosine stress, reflecting the coronary circulation in patients during long-term follow-up of severe Covid-19. Neither ΔT1 nor ΔT2 can be used to assess MPR in patients with severe Covid-19.
46.	Nickander, J, et al. (author) Stress native T1 and native T2 mapping compared to myocardial perfusion reserve in long-term follow-up of severe Covid-19 2023 In: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 13:1, s. 4159- Journal article (peer-reviewed)abstract Severe Covid-19 may cause a cascade of cardiovascular complications beyond viral pneumonia. The severe inflammation may affect the microcirculation which can be assessed by cardiovascular magnetic resonance (CMR) imaging using quantitative perfusion mapping and calculation of myocardial perfusion reserve (MPR). Furthermore, native T1 and T2 mapping have previously been shown to identify changes in myocardial perfusion by the change in native T1 and T2 during adenosine stress. However, the relationship between native T1, native T2, ΔT1 and ΔT2 with myocardial perfusion and MPR during long-term follow-up in severe Covid-19 is currently unknown. Therefore, patients with severe Covid-19 (n = 37, median age 57 years, 24% females) underwent 1.5 T CMR median 292 days following discharge. Quantitative myocardial perfusion (ml/min/g), and native T1 and T2 maps were acquired during adenosine stress, and rest, respectively. Both native T1 (R2 = 0.35, p < 0.001) and native T2 (R2 = 0.28, p < 0.001) correlated with myocardial perfusion. However, there was no correlation with ΔT1 or ΔT2 with MPR, respectively (p > 0.05 for both). Native T1 and native T2 correlate with myocardial perfusion during adenosine stress, reflecting the coronary circulation in patients during long-term follow-up of severe Covid-19. Neither ΔT1 nor ΔT2 can be used to assess MPR in patients with severe Covid-19.
47.	Oellers, D., et al. (author) New experimental upper limit of the electron-proton spin-flip cross-section 2014 In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 759, s. 6-9 Journal article (peer-reviewed)abstract In a previous publication, measurements of the depolarization of a stored proton beam by interaction with a co-propagating unpolarized electron beam at low relative energy have been presented and an upper limit of about 3 x 10(7) b for the electron-proton spin flip cross-section was determined. A refined analysis presented in this paper reduces the previous upper limit by a factor of three by the introduction of a new procedure that, also makes use of non-identified particles.
48.	Petrén, Henrik, et al. (author) eta-meson production in proton-proton collisions at excess energies of 40 and 72 MeV 2010 In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 82:5, s. 055206- Journal article (peer-reviewed)abstract The production of eta mesons in proton-proton collisions has been studied using the WASA detector at the CELSIUS storage ring at excess energies of Q = 40 MeV and Q = 72 MeV. The eta was detected through its 2 gamma decay in a near-4 pi electromagnetic calorimeter, whereas the protons were measured by a combination of straw chambers and plastic scintillator planes in the forward hemisphere. About 6.9 x 10(4) and 9.3 x 10(4) events were found at Q = 40 MeV and Q = 72 MeV, respectively, with background contributions of less than 5%. A simple parametrization of the production cross section in terms of low partial waves was used to evaluate the acceptance corrections. Strong evidence was found for the influence of higher partial waves. The Dalitz plots show the presence of p waves in both the pp and the eta {pp} systems and the angular distributions of the eta in the center-of-mass frame suggest the influence of d-wave eta mesons.
49.	Przewoski, B., et al. (author) Measurement of spin correlation coefficients in polarized p polarized p ->d pi 2000 In: Phys. Rev. C. - : American Physical Society. ; 61, s. 064604-1 Journal article (peer-reviewed)
50.	Rantanen, T, et al. (author) Evaluation of Media and Communication Studies in Higher Education in Finland 2002 Reports (pop. science, debate, etc.)

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