### Regular Series

#### XXXI Mazurian Lakes Conference on Physics

Physics 1909: A Portrait of the Field Hundred Years Ago

Acta Phys. Pol. B 41, 229 (2010)

page 229 •

abstract

Many physicists believe that after the discoveries of Max Planck (1900) and Albert Einstein (1905) physics was quickly transformed into a modern one based on relativistic and quantum principles. The study of the physics community and the physics papers published hundred years ago, in 1909, shows however, that only very few physicists took interest in the novelties while the bulk of physics remained classical and much oriented towards practical applications. Details are given on the physics topics, the strength of physics in various countries, the most important periodicals and prominent physicists of that time.

Precision Physics with Low-energy Antiprotons — from Antiproton Decelerator to FLAIR

Acta Phys. Pol. B 41, 249 (2010)

page 249 •

abstract

Experiments with low-energy antiprotons are currently performed at the Antiproton Decelerator of CERN. The main experiments deal with the spectroscopy of antiprotonic helium, an exotic three-body system, and the formation and spectroscopy of antihydrogen. A next generation facility FLAIR (Facility for Low-energy Antiproton Research) is planned at the FAIR facility, generating a factor 100 higher flux of stopped antiprotons and also offering continuous antiprotons beam, which will enable nuclear and particle physics type experiments.

New Physics Opportunities in the Charm/Tau Region: the BESIII — Experiment in Beijing

Acta Phys. Pol. B 41, 261 (2010)

page 261 •

abstract

A new facility for precision physics in the charm/tau energy regime has become operational at the Institute for High Energy Physics (IHEP) in Beijing, China. It features the dual ring $e^+ e^-$ collider BEPCII operating at luminosities up to $10^{33}\,{\rm cm}^{-2}{\rm s}^{-1}$ and at a centre-of-mass energy between 2 GeV and 4.6 GeV. BESIII, a new state-of-the-art detector has been built and successfully commissioned. This contribution describes the facility, presents a brief overview of the physics program and shows preliminary results from first run in spring 2009 which collected a sample of $156~{\rm pb}^{-1}$ at the $\psi (2S)$ resonance.

Subthreshold $\bar {N}N$ Amplitudes from the Lightest Antiprotonic Atoms

Acta Phys. Pol. B 41, 269 (2010)

page 269 •

abstract

The data from the simplest antiprotonic-hydrogen and -helium atoms can be used to extract the elastic antiproton–nucleon scattering amplitudes below the antinucleon–nucleon threshold. These are interesting since two quasi-bound $S$ and $P$ antiproton–nucleon states are likely to exist in this region. Such states, indicated by the phenomenological Paris potential, find support in the atomic level widths. Additional evidence for the broad $S$-wave state comes from $J$/$\psi$ physics. The other narrow $P$-wave state requires further experimental checks.

Feasibility Studies for the $\overline {\rm P}$ANDA Experiment at FAIR

Acta Phys. Pol. B 41, 277 (2010)

page 277 •

abstract

$\overline {\rm P}$ANDA, the detector to study AntiProton ANnihilations at DArmstadt, will be installed at the future international Facility for Anti-proton and Ion Research (FAIR) in Darmstadt, Germany. The $\overline {\rm P}$ANDA physics program is oriented towards the studies of the strong interaction and hadron structure performed with the highest quality beam of anti-protons [1]. In the preparation for $\overline {\rm P}$ANDA experiments, large-scale simulation studies are being performed to validate the performance of all individual detector components and to advice on detector optimisation. The feasibility of the analysis strategies together with the calibration methods are being studied. Simulations were carried out using the framework called PandaROOT [2], based on ROOT and the Virtual Monte Carlo concept [3].

Production of the Double Hypernuclei with Antiprotons at PANDA

Acta Phys. Pol. B 41, 285 (2010)

page 285 •

abstract

After a brief review of the properties of the $S=-2$ systems and of the data collected up today, the technique that will be used in the PANDA experiment at FAIR to produce and stop the ${\mit \Xi }^{-}$ hyperons is illustrated and the expected rates at HESR are reported.

Response of Cooled PWO Scintillators to Low-Energy Gamma-Rays and Its Importance for Spectroscopic Measurements of Charmonium with PANDA

Acta Phys. Pol. B 41, 291 (2010)

page 291 •

abstract

Identification of $\pi ^0$ and $\eta$ mesons by detecting both $\gamma$-rays from their decay is a prerequisite for suppressing undesired background in studies of photon transitions between the states of charmonium. To achieve this goal the detection threshold of the PANDA electromagnetic calorimeter (EMC) should be as low as possible. We demonstrate with Monte-Carlo simulations how the signal to background ratio changes for the chosen $\bar {p}p \rightarrow h_c \rightarrow \gamma \eta _c$ reaction and the assumed exclusive $\eta _{c}$ decay mode with the EMC threshold. The measurement of the $h_{c}$ total width with a reasonable accuracy is feasible but time consuming in the high-resolution mode of HESR operation. Our PWO resolution measurement at low photon energies corroborates the trend established at the MAMI facility in the 40.9–674.5 MeV energy range.

Transport Calculations of $\bar p$-Nucleus Interactions

Acta Phys. Pol. B 41, 299 (2010)

page 299 •

abstract

The Giessen Boltzmann–Uehling–Uhlenbeck transport model is extend-ed and applied to the $\bar p$-nucleus interactions in a wide beam momentum range. The model calculations are compared with the experimental data on $\bar p$-absorption cross-sections on nuclei with an emphasis on extraction of the real part of an antiproton optical potential. The possibility of the cold compression of a nucleus by an antiproton in-flight is also considered.

Polarized Antiprotons — How and Why?

Acta Phys. Pol. B 41, 305 (2010)

page 305 •

abstract

A brief report is given on the ongoing experimental efforts to produce a beam of polarized antiprotons. If successful such beams may be used in a second stage of the FAIR/HESR-facility currently under construction in Darmstadt (Germany). For further information readers are referred to the given references.

Antiprotonic Atoms as a Tool to Study the Nuclear Periphery

Acta Phys. Pol. B 41, 311 (2010)

page 311 •

abstract

The nuclear periphery was studied using antiprotons. Two experimental methods were applied: analysis of the antiproton annihilation residues one mass unit lighter than the target mass by nuclear spectroscopy and the measurement of strong interaction effects on antiprotonic level widths and shifts. 26 isotopes from a wide range of mass numbers ($40\lt A\lt 238$) were investigated. Neutron density distributions and difference of neutron and proton root-mean-square radii for these isotopes were deduced.

${\mit \Lambda }$-Hypernuclear Production in ($K^-_{\rm stop}, \pi$) Reactions

Acta Phys. Pol. B 41, 317 (2010)

page 317 •

abstract

We report on calculation of the ${\mit \Lambda }$-hypernuclear production induced by the stopped $K^{\,-}$. The calculation was performed within the framework of the distorted wave impulse approximation and employed chirally motivated model for the microscopic description of the elementary $K^{\,-}$–nucleon process. The sensitivity of the calculation was tested with various wave functions of both the kaon in the initial state and the pion in the final state. Our results are closer to the experimental values then the results of previous calculations.

$K^-pp$ Studied with Coupled-channel Complex Scaling Method

Acta Phys. Pol. B 41, 323 (2010)

page 323 •

abstract

We introduce the recent status of theoretical studies of the most essential kaonic nucleus $K^{\,-}pp$. The calculated binding energy and decay width are strongly dependent on theoretical models. In particular, there is a large discrepancy between the results of a variational calculation and a Faddeev calculation, in spite that $\bar {K}N$ potentials used in both calculations are constrained by chiral SU(3) theory. This discrepancy is expected to be caused by $\pi {\mit \Sigma } N$ three-body dynamics which might be missing in the variational calculation. In order to consider this issue, we propose “Coupled-channel Complex Scaling Method” which can be regarded as an extended method of the variational scheme.

all authors

L. Tolos, D. Cabrera, D. Gamermann, C. Garcia-Recio, R. Molina, J. Nieves, E. Oset, A. Ramos

Strange and Charm Mesons at FAIR

Acta Phys. Pol. B 41, 329 (2010)

page 329 •

abstract

We study the properties of strange and charm mesons in hot and dense matter within a self-consistent coupled-channel approach for the experimental conditions of density and temperature expected for the CBM experiment at FAIR/GSI. The in-medium solution at finite temperature accounts for Pauli blocking effects, mean-field binding of all the baryons involved, and meson self-energies. We analyse the behaviour in this hot and dense environment of dynamically-generated baryonic resonances together with the evolution with density and temperature of the strange and open-charm meson spectral functions. We test the spectral functions for strange mesons using energy-weighted sum rules and finally discuss the implications of the properties of charm mesons on the $D_{s0}(2317)$ and the predicted $X(3700)$ scalar resonances.

CBM Experiment at FAIR

Acta Phys. Pol. B 41, 341 (2010)

page 341 •

abstract

The Compressed Baryonic Matter (CBM) project at the future accelerator center FAIR will be a dedicated heavy-ion experimental operating in fixed target mode at beam energies from 8 to 45 $A$ GeV. The ultimate goal of the research program is to explore the QCD phase diagram in the range of moderate temperature but the highest net-baryon densities. The CBM detector concept aims to obtain feasibility of measurement of hadronic, leptonic and photonic observables at interaction rates up to 10 MHz. It will allow to detect extremely rare probes such as charm near its production threshold. The CBM experiment will enter a new era with diagnostic probes never accessible before in the FAIR energy range, and thus has a unique research potential.

Nonextensive Critical Effects in the Nambu–Jona-Lasinio Model

Acta Phys. Pol. B 41, 351 (2010)

page 351 •

abstract

The critical phenomena in strongly interaction matter are generally investigated using the mean-field model and are characterized by well defined critical exponents. However, such models provide only average properties of the corresponding order parameters and neglect altogether their possible fluctuations. Also the possible long range effect are neglected in the mean field approach. Here we investigate the critical behavior in the nonextensive version of the Nambu–Jona-Lasinio model (NJL). It allows to account for such effects in a phenomenological way by means of a single parameter $q$, the nonextensivity parameter. In particular, we show how the nonextensive statistics influence the region of the critical temperature and chemical potential in the NJL mean field approach.

The Optical Model Potential of the ${\mit \Sigma }$ Hyperon in Nuclear Matter

Acta Phys. Pol. B 41, 357 (2010)

page 357 •

abstract

We present our attempts to determine the optical model potential $U_{\mit \Sigma } = V_{\mit \Sigma } -iW_{\mit \Sigma }$ of the ${\mit \Sigma }$ hyperon in nuclear matter. We analyze the following sources of information on $U_{\mit \Sigma }$: ${\mit \Sigma } N$ scattering, ${\mit \Sigma }^{\,-}$ atoms, and final state interaction of ${\mit \Sigma }$ hyperons in the $(\pi ,K^{\,+})$ and $(K^{\,-}.\pi )$ reactions on nuclear targets. We conclude that $V_{\mit \Sigma }$ is repulsive inside the nucleus and has a shallow attractive pocket at the nuclear surface. These features of $V_{\mit \Sigma }$ are consistent with the Nijmegen model F of the hyperon–nucleon interaction.

all authors

B. Ramstein, G. Agakichiev, C. Agodi, A. Balanda, G. Bellia, D. Belver, A. Belyaev, A. Blanco, M. Böhmer, J.L. Boyard, P. Braun-Munzinger, P. Cabanelas, E. Castro, T. Christ, M. Destefanis, J. Díaz, F. Dohrmann, A. Dybczak, L. Fabbietti, O. Fateev, P. Finocchiaro, P. Fonte, J. Friese, I. Fröhlich, T. Galatyuk, J.A. Garzón, R. Gernhäuser, A. Gil, C. Gilardi, M. Golubeva, D. González-Díaz, E. Grosse, F. Guber, M. Heilmann, T. Hennino, R. Holzmann, A. Ierusalimov, I. Iori, A. Ivashkin, M. Jurkovic, B. Kämpfer, K. Kanaki, T. Karavicheva, D. Kirschner, I. Koenig, W. Koenig, B.W. Kolb, R. Kotte, A. Kozuch, A. Krása, F. Křížek, R. Krücken, W. Kühn, A. Kugler, A. Kurepin, J. Lamas-Valverde, S. Lang, J.S. Lange, K. Lapidus, L. Lopes, M. Lorenz, T. Liu, L. Maier, A. Mangiarotti, J. Marín, J. Markert, V. Metag, B. Michalska, J. Michel, D. Mishra, E. Morinière, J. Mousa, C. Müntz, L. Naumann, R. Novotny, J. Otwinowski, Y.C. Pachmayer, M. Palka, Y. Parpottas, V. Pechenov, O. Pechenova, T. Pérez Cavalcanti, J. Pietraszko, W. Przygoda, A. Reshetin, A. Rustamov, A. Sadovsky, P. Salabura, A. Schma, R. Simon, Yu.G. Sobolev, S. Spataro, B. Spruck, H. Ströbele, J. Stroth, C. Sturm, M. Sudol, A. Tarantola, K. Teilab, P. Tlustý, M. Traxler, R. Trebacz, H. Tsertos, I. Veretenkin, V. Wagner, M. Weber, M. Wisniowski, J. Wüstenfeld, S. Yurevich, Y.V. Zanevsky, P. Zhou, P. Zumbruch

Study of Elementary Reactions with the HADES Dielectron Spectrometer

Acta Phys. Pol. B 41, 365 (2010)

page 365 •

abstract

Results obtained with the HADES dielectron spectrometer at GSI are discussed, with emphasis on dilepton production in elementary reactions.

What Can We Learn from the $\phi$(1020) Meson Production at SIS Energies?

Acta Phys. Pol. B 41, 379 (2010)

page 379 •

abstract

Kaon yields measured in nucleus–nucleus collisions can be affected by the decays of $\phi$(1020) mesons into hadronic channel. In this contribution we report on the study of $\phi$ meson production in Al+Al collisions at $1.9 A$ GeV. The measurement was done at SIS18 (GSI Darmstadt) with the FOPI Spectrometer. The fraction of the $K^{\,-}$ yield originating from $\phi$ decay was found to be $(10\pm 5)\%$ in rough agreement with recent HADES measurements for Ar+KCl system.

all authors

K. Schmidt, A. Benisz, A. Bubak, A. Grzeszczuk, S. Kowalski, W. Zipper, F. Amorini, A. Anzalone, L. Auditore, V. Baran, J. Brzychczyk, G. Cardella, S. Cavallaro, M.B. Chatterjee, M. Colonna, E. DeFilippo, M. DiToro, W. Gawlikowicz, E. Geraci, P. Guazzoni, E. La Guidara, G. Lanzalone, J. Lukasik, C. Maiolino, Z. Majka, N. Nicolis, A. Pagano, M. Papa, E. Piasecki, S. Pirrone, R. Planeta, G. Politi, F. Porto, F. Rizzo, P. Russotto, K. Siwek-Wilczynska, I. Skwira-Chalot, A. Sochocka, L. Swiderski, A. Trifiro, M. Trimarchi, J.P. Wieleczko, J. Wilczynski, L. Zetta

Light Fragments Production and Isospin Dependences in Sn+Ni and Sn+Al Central Collisions at 25 MeV/$A$ and 35 MeV/$A$ from REVERSE/ISOSPIN Experiments

Acta Phys. Pol. B 41, 387 (2010)

page 387 •

abstract

This paper presents the physical analysis results for the following reactions: $^{124}$Sn$+ ^{64}$Ni, $^{124}$Sn$+ ^{27}$Al, $^{124}$Sn$+ ^{58}$Ni at 35 MeV/$A$ and 25 MeV/$A$. The main goal of this studies was to find observables sensitive to isospin effects and to present the similarities/differences between the systems characterised by various charge asymmetry factor, defined as $I=(N-Z)$/$A$. Theoretical simulations based on the Quantum Molecular Dynamics (QMD) model have been performed in order to compare them with the results of the analysis of experimental data. The first phase of the reaction was carried out with the code CHIMERA [1]. The sequential decay of hot fragments was simulated by the code COOLER [2]. The conclusions are as follows: there are observables sensitive to the isospin of the system, such as the Light Charged Particles (LCP) emission and their sensitivity is demonstrated more prominently in the analysis of central collisions at 35 MeV/$A$. The theoretical calculations do not reproduce these relations well.

${\pi }^0$ Meson Production in Ta+Au Collisions at 40A MeV

Acta Phys. Pol. B 41, 393 (2010)

page 393 •

abstract

Angular and transverse momentum distributions have been measured for the Ta+Au collisions at 40$A$ MeV using the TAPS photon spectrometer installed at GANIL, Caen. The data sample of $528\, {\pi }^0$ mesons is superior compared to the previous measurement at the beam energy being only 14% of the free nucleon–nucleon threshold. The angular distribution has been found to be almost symmetric and can be described well within a parametrisation using a second-order Legendre polynomial. The correction of data by the simple reabsorption model based on static geometrical considerations indicates, that the angular distribution of primordial neutral mesons might be almost isotropic, in contrast to many of the results obtained from the reanalysis of published data. The transverse momentum spectrum cannot be reasonably described within the thermal model, even when the spectrum is corrected for the reabsorption effects.

all authors

G. Mandaglio, M. Manganaro, G. Giardina, R. Di Salvo, A. Fantini, A. D'Angelo, D. Franco, D. Moricciani, P. Levi Sandri, C. Schaerf, V. Vegna

Data Analysis and Event Identification of the $\gamma + n \rightarrow \pi ^- + p$ Reaction

Acta Phys. Pol. B 41, 399 (2010)

page 399 •

abstract

We present the selection method of events originating from the $\gamma +n\rightarrow \pi ^- + p$ reaction obtained by bombarding a liquid deuterium target with a polarised $\gamma$ beam of 0.6–1.5 GeV in the framework of the Graal experiment. We show the effect of bi-dimensional cuts (obtained combining measured quantity and reconstructed kinematic variables) and hardware constraints in order to reduce the contamination coming from the concurrent reaction channels. We describe a new three-dimensional cut based on the Fermi momentum reconstruction able to obtain a great increase of the signal/noise ratio. We determine the reaction vertex by using the precise measurement coming from the multi-wire proportional chambers (MWPCs) detectors: in this way we can reconstruct the shape of the spatial distribution of the beam and its position with respect to the target. By the simulation we estimate the contamination degree due to the other reaction channels so we can test the reliability of our method.

Properties of Dense Baryonic Matter at 2$A$ GeV

Acta Phys. Pol. B 41, 405 (2010)

page 405 •

abstract

Phase space distributions and integrated yields of baryons from central collisions at 1.9 $A$ GeV are discussed in context of thermalization problem. Elongations of rapidity distributions of protons, deuterons, and inclusive baryon samples are shown for energies of 0.04–1.9 $A$ GeV and wide range of system sizes. Inverse slopes from a Boltzmann fit to transverse mass distributions are systematized as a function of particle’s mass. Experimental ratios of integrated yields are compared to the Statistical Model and UrQMD. Kinematic temperature parameter characterizing Ni+Ni collisions at 1.93 $A$ GeV is found to be higher than the one obtained within the Statistical Model.

Strangeness Production in Heavy-ion Collisions at Intermediate Energies Revisited with Pions

Acta Phys. Pol. B 41, 415 (2010)

page 415 •

abstract

In this contribution, we give a short summary of experimental results on the production of strangeness, especially of charged kaons, in heavy-ion collisions at intermediate energies. In particular, we discuss the possible interpretation of these results, which suggests that properties of hadrons are modified in a dense nuclear matter. We point out to problems connected to this interpretation, for example, unknown cross-sections of the underlying elementary process. We discuss in detail an experiment that aimed at measuring these cross-sections at the normal nuclear matter density. We present experimental results on the production of neutral kaons in collisions of pions at 1.15 GeV/$c$ incident momentum with C, Al, Cu, Sn, Pb nuclei. We focus on the inclusive production cross-sections and the phase-space distributions of the produced $K^{\,0}$ mesons, which both shed more light on the problematic issues and point out to the modifications of the elementary reaction amplitudes as well as of the $KN$ potentials in the baryonic matter at the normal nuclear matter density.

NA49 and NA61/SHINE Experiments: Results and Perspectives

Acta Phys. Pol. B 41, 427 (2010)

page 427 •

abstract

The Super Proton Synchrotron (SPS) covers one of the most interesting regions of the QCD phase diagram $(T - \mu _{\rm B})$. On the one hand, there are indications that the energy threshold for deconfinement is reached already at low SPS energies. On the other hand, theoretical calculations locate the QCD critical end-point at energies accessible at the SPS. In this paper the NA49 signatures of the onset of deconfinement are presented. Results are shown on pion production, the kaon to pion ratio, slopes of transverse mass spectra (“temperature”), and event-by-event particle ratio fluctuations versus collision energy, for central Pb + Pb interactions. Next, we show possible indications of the critical point in event-by-event mean transverse momentum and multiplicity fluctuations. Finally, we discuss the future ion program of the NA61/SHINE experiment (energy scan with light ions).

Scaled Momentum Spectra in Deep Inelastic Scattering at HERA

Acta Phys. Pol. B 41, 441 (2010)

page 441 •

abstract

Charged particle production has been studied in deep inelastic scattering (DIS) using an integrated luminosity of about 0.44 fb$^{-1}$ taken with the ZEUS detector at HERA. The fragmentation properties of the struck quark in deep inelastic scattering have been investigated in the current fragmentation region of the Breit frame as a function of the exchanged boson virtuality $Q^2$. The measured evolution of scaled momentum distributions are compared to next-to-leading order calculations convoluted with the fragmentation functions obtained from $e^+e^-$ experiments. Scaling violations are observed. The scaled momentum spectra are also compared to predictions based on a modified leading-logarithmic QCD approximation and Monte Carlo event generators.

all authors

S. Mianowski, H. Czyrkowski, R. Dąbrowski, W. Dominik, Z. Janas, K. Miernik, M. Pfützner, A.S. Fomichev, M.S. Golovkov, L.V. Grigorenko, S.A. Krupko, S.I. Sidorchuk, R.S. Slepnev, S.V. Stepantsov, G.M. Ter-Akopian

Imaging the Decay of $^{8}$He

Acta Phys. Pol. B 41, 449 (2010)

page 449 •

abstract

The feasibility of the $\beta$ decay study of $^{8}$He with the use of a time projection chamber has been investigated. It is shown that $\beta$-delayed neutron emission branches of $^{8}$He can be identified by registration of tracks of the recoiling $^{7}$Li nuclei. Evidence for neutron emission from a highly excited $^{8}$Li state was obtained. New possibilities to study $\beta$-decay of $^{8}$He into the $\alpha +t+n$ continuum are demonstrated by showing that the full kinematics of such events can be reconstructed. Observed correlations will provide new insight into the mechanism of this decay process. Planned developments of the detection setup are discussed.

all authors

F. Herfurth, W. Barth, G. Clemente, L. Dahl, P. Gerhard, M. Kaiser, O. Kester, H.-J. Kluge, S. Koszudowski, C. Kozhuharov, W. Quint, A. Sokolov, T. Stöhlker, G. Vorobjev, J. Pfister, U. Ratzinger, A. Sauer, A. Schempp

HITRAP — Heavy, Highly-charged Ions and Antiprotons at Rest

Acta Phys. Pol. B 41, 457 (2010)

page 457 •

abstract

At the GSI Helmholtz-Center for Heavy-Ion Research, highly-charged ions up to bare uranium are produced by passing a 400 MeV/$u$ beam through matter. Subsequently, the ions are decelerated, first in the experimental storage ring ESR from 400 to 4 MeV/$u$ and in the HITRAP linear decelerator. It consists of an interdigital H-type (IH) structure and a radio-frequency quadrupole (RFQ) structure operated in inverse mode and decelerates the ions first from 4 MeV/$u$ to 0.5 MeV/$u$ and then to 6 keV/$u$. Deceleration down to 0.5 MeV/$u$ has been demonstrated but its efficiency needs to be improved.

all authors

J. Szerypo, E. Gartzke, D. Habs, V.S. Kolhinen, J.B. Neumayr, P.G. Thirolf, C. Weber

Progress of the MLLTRAP System in Munich

Acta Phys. Pol. B 41, 463 (2010)

page 463 •

abstract

The MLLTRAP is a Penning trap system designed to perform high-accuracy nuclear mass measurements in its final stage aiming to use highly-charged ions. The goal is to reach an accuracy of 10$^{-10}$, which is required for high-precision fundamental physics studies like the determination of fundamental constants and measurements of electron binding energies for QED at strong fields. In the first development stage the setup will work with singly-charged ions. First results of systematic uncertainty investigations are presented.

all authors

J. Kurpeta, J. Rissanen, V.-V. Elomaa, T. Eronen, J. Hakala, A. Jokinen, P. Karvonen, I.D. Moore, H. Penttilä, A. Płochocki, S. Rahaman, S. Rinta-Antila, J. Ronkainen, A. Saastamoinen, T. Sonoda, J. Szerypo, W. Urban, Ch. Weber, J. Äystö

Progress in Trap Assisted $\beta$ Decay Spectroscopy of $^{115}$Ru

Acta Phys. Pol. B 41, 469 (2010)

page 469 •

abstract

The use of ion trap purified rare isotope beam in combination with coincidence $\beta$ and $\gamma$ spectroscopy is presented. Its exemplified with the $\beta$ decay of a very neutron-rich isotope $^{115}$Ru. Thanks to a considerable increase of yield from the JYFLTRAP ion trap system beta decay of $^{115}$Ru was reinvestigated. In consequence new gamma transitions and excited levels fed by beta decay were established in $^{115}$Rh. Results of half-life measurements are also presented. The very exotic nuclei of interest were produced in proton induced fission of $^{238}$U target, separated with the IGISOL mass separator and purified to monoisotopic level with a Penning trap.

all authors

A.S. Fomichev, G.M. Ter-Akopian, V. Chudoba, A.V. Daniel, M.S. Golovkov, V.A. Gorshkov, L.V. Grigorenko, S.A. Krupko, Yu.Ts. Oganessian, S.I. Sidorchuk, R.S. Slepnev, S.V. Stepantsov, S.N. Ershov, V.K. Lukyanov, B.V. Danilin, A.A. Korsheninnikov, V.Z. Goldberg, M. Pfützner, I.G. Mukha, H. Simon, O.B. Tarasov, N.K. Timofeyuk, M.V. Zhukov, K. Lawrie, R.T. Newman

The Suggested New Fragment Separator ACCULINNA-2

Acta Phys. Pol. B 41, 475 (2010)

page 475 •

abstract

We present new project of fragment separator ACCULINNA-2 that is being planned to be constructed in Flerov Laboratory of Nuclear Reaction, JINR. The ACCULINNA-2 facility is not intended to compete with the new large in-flight RIB facilities. It should complement the existing/constructed facilities in certain fields. Namely, ACCULINNA-2 should provide high intensity RIBs in the lowest energy range attainable for in-flight separators.

EXL, R$^3$B and ELISe Projects at FAIR

Acta Phys. Pol. B 41, 481 (2010)

page 481 •

abstract

In this contribution, the physics program for three of the experiments at FAIR-NuSTAR, namely EXL, R$^3$B and ELISe will be briefly outlined. All these experiments aim to study the structure and the dynamics of radioactive ions which collide with either light ions in an inverse kinematics, or electrons in a collider mode. Although the physics issues addressed in all three are rather similiar, the experimental equipment used for them are quite different. The experimental plans will, then, also be briefly discussed.

Present and Future of HISPEC

Acta Phys. Pol. B 41, 493 (2010)

page 493 •

abstract

The HISPEC (High-resolution in-flight SPECtroscopy) project is part of the core experimental facility at FAIR. It is aimed at nuclear structure and reaction studies, using high-resolution $\gamma$-ray spectroscopy as its main tool. Experiments using the same techniques were performed at the for-runner RISING project at the existing GSI. Some HISPEC detectors are already in the production phase, with the first commissioning experiments taking place in 2010. The physics case, the experimental setup, the opportunities opened are discussed.

all authors

P. Bednarczyk, J. Grębosz, M. Kmiecik, A. Maj, W. Męczyński, S. Myalski, J. Styczeń, C. Domingo-Pardo, P. Doornenbal, J. Gerl, M. Górska, H.J. Wollersheim, J. Jolie, P. Reiter, A. Bracco, F. Camera

In-beam $\gamma$-ray Angular Distribution and Lifetime Measurements — Experience from Rising and Perspectives at FAIR

Acta Phys. Pol. B 41, 505 (2010)

page 505 •

abstract

RISING experiments delivered important knowledge on difficulties in performing prompt in-beam $\gamma$-ray spectroscopy measurements, caused by the use of very fast radioactive beams. The obtained results pointed out possible ways to suppress the overwhelming $\gamma$-ray background that should be considered in setting up new facilities planned at GSI and FAIR. In the course of the RISING campaign, the spectroscopy methods: $\gamma$-ray angular distribution and lifetime measurements useful in deducing $B({\rm E2})$ transition rates were developed. They can be effectively applied in experiments with the new generation $\gamma$-ray detector array AGATA.

Direct Mass Measurements of Exotic Nuclei in Storage Rings

Acta Phys. Pol. B 41, 511 (2010)

page 511 •

abstract

Mass measurements of exotic nuclei is a fast developing field which is essential for basic nuclear physics and a wide range of applications. The method of storage ring mass spectrometry has many advantages: (1) a large amount of nuclides can be simultaneously measured; (2) very short-lived ($T_{1\,/\,2} \gtrsim$ 50 $\mu$s) and very rare species (yields down to single ions) can be accessed; (3) nuclides in several atomic charge states can be investigated; (4) half-life measurements can be performed with time-resolved mass spectrometry. In this contribution we concentrate on some recent achievements and future perspectives of the storage ring mass spectrometry.

all authors

J. Kurcewicz, F. Bosch, H. Geissel, Yu.A. Litvinov, N. Winckler, K. Beckert, P. Beller, D. Boutin, C. Brandau, L. Chen, C. Dimopoulou, H.G. Essel, B. Fabian, T. Faestermann, A. Fragner, B. Franzke, E. Haettner, M. Hausmann, S. Hess, P. Kienle, R. Knöbel, C. Kozhuharov, S.A. Litvinov, L. Maier, M. Mazzocco, F. Montes, A. Musumarra, C. Nociforo, F. Nolden, Z. Patyk, W.R. Plass, A. Prochazka, R. Reda, R. Reuschl, C. Scheidenberger, M. Steck, T. Stöhlker, B. Sun, K. Takahashi, S. Torilov, M. Trassinelli, H. Weick, M. Winkler

Studies of Two-body $\beta$-Decays at the FRS–ESR Facility

Acta Phys. Pol. B 41, 525 (2010)

page 525 •

abstract

A combination of the in-flight projectile fragment separator and the heavy-ion storage-cooler ring has been used to produce, store and investigate cooled highly charged ions. The results of recently performed experiments at GSI Darmstadt studying two-body $\beta$-decays of H-like and He-like ions are presented. The technique of Schottky lifetime spectroscopy has been applied to explore the electron capture and bound-state $\beta ^-$ decay processes of ions circulating in the heavy-ion storage ring.

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