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The ASY-EOS experiment at GSI laboratory measured the direct and elliptic flow of neutrons and light charged particles in the reaction 197Au+197Au at 400 A MeV incident energy. The ratio of elliptic flow of neutrons with respect to that of the light charged particles was used as main experimental observable to probe the density dependence of the symmetry energy term of the nuclear equation of state. Results, obtained by comparison of the experimental data with the UrQMD model predictions, strongly support a moderately soft to linear density dependence of the symmetry energy at suprasaturation densities below 2ρ0. [ABSTRACT FROM AUTHOR]

The article discusses the use of thermoluminescence detectors (TLD) in brachytherapy. Topics discussed include the use of diamonds in TLD as it offers several benefits including good sensitivity to ionising radiation and linearity of up to 3 Gy, the proper method of measuring dose with TLD and the use of TLD in evaluating dose distribution in an x-ray tube. Also mentioned is its use for dosimetry of BNCT beam.

KRATTA, a new, low threshold, broad energy range triple telescope array has been built to measure the energy, emission angles and isotopic composition of light charged reaction products. It has been equipped with fully digital chains of electronics. The array performed very well during the ASY-EOS experiment, conducted in May 2011 at GSI. The structure and performance of the array are presented using the first experimental results. [ABSTRACT FROM AUTHOR]

The elliptic-flow ratio of neutrons with respect to protons in reactions of neutron rich Heavy-Ion at intermediate energies has been recently proposed as an observable sensitive to the strength of the symmetry term in the nuclear equation of state (EOS) at supra-saturation densities. The recent results obtained from the existing FOPI/LAND data for 197Au+197Au collisions at 400 MeV/nucleon in comparison with the UrQMD model allowed a first estimate of the symmetry term of the EOS but suffer from a considerable statistical uncertainty. In order to obtain an improved data set for Au+Au collisions and to extend the study to other systems, a new experiment was carried out at the GSI laboratory by the ASY-EOS collaboration in May 2011. [ABSTRACT FROM AUTHOR]

The project of the first Polish underground laboratory SUNLAB, in the Polkowice-Sieroszowice copper mine, belonging to the KGHM Polska Miedz S.A. holding, is presented. Two stages of the project are foreseen: SUNLAB1 (a small laboratory in the salt layer exhibiting extremely low level of natural radioactivity) and SUNLAB2 (a big laboratory in the anhydrite layer, able to host the next generation liquid argon detector-GLACIER, which is considered within the LAGUNA FP7 project). The results of the natural radioactivity background measurements performed in the Polkowice-Sieroszowice salt cavern are also briefly summarized. [ABSTRACT FROM AUTHOR]

Using fragment-separator COMBAS [1] in forward-angle measurements the velocity, isotopic and element distributions of products with Z<7 in 11B(33 AMeV)+9Be reaction have been studied. The yields of 6,8He and 9Li isotopes on the 9Be thick target (332.6 mg/cm2) as a function of momentum acceptance of fragment -separator COMBAS have been measured. The production rates per 1pμA of the primary beam of exotic nuclei of 6He(6.9·105 pps), 8He(2·104 pps) and 9Li(4.3·10 5pps) which can be used as secondary radioactive beams of halo -like nuclei have been determined. The two-neutron halo nuclei 6,8He and 9Li are of great current interest both as very neutron-rich nuclei with a significant neutron skin and in understanding the interactions of very neutron-rich nuclei. The 9Li beam may be helpful in understanding of sub barrier fusion enhancement independent of the presence of the halo nucleons in used neutron—rich projectiles. [ABSTRACT FROM AUTHOR]

The ionization beam profile monitor (IBPM) for charged particles has been constructed and tested. Its principle of operation based on the ionization of the residual gas in the ion pipe is described. Vbeam code for data acquisition and visualization has been written and applied to the control system. The IBPM has been used for routine control of the beam profile and beam intensity in experiments performed on the COMBAS separator. Examples of measured ion beam profiles at the 11B beam at energy of 33 MeV/A with intensity of 1010 – 1012 pps are presented. Monitor has been placed directly after the thin production target. Scanned area was 5×5 cm2 with uniform 1 mm spatial resolution over the scanning region. Once calibrated it serves as the useful monitor of the beam position, profile and its intensity. The IBPM does not affect the beam and for an accelerator operator is a profitable tool for a continuous control of the beam. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

We present new results from the PHOBOS experiment at RHIC on event-by-event fluctuations of particle multiplicities and angular distributions in nucleus-nucleus collisions at RHIC. Our data for Au+Au collisions at √sNN = 200 GeV show that at a level of 10..4 or less, no rare, large-amplitude fluctuations in the total multiplicity distributions or the shape of the pseudorapidity distributions are observed. We however find significant short-range multiplicity correlations in these data, that can be described as particle production in clusters. In Cu+Cu collisions, we observe large final-state azimuthal anisotropies v2. A common scaling behavior for Cu+Cu and Au+Au for these anisotropies emerges when fluctuations in the initial state geometry are taken into account. [ABSTRACT FROM AUTHOR]

According to the quark model, the masses of η and η′ mesons should be almost equal. However, the empirical values of these masses differ by more than a factor of two. Similarly, though they have almost the same quark-antiquark content, the total cross section for the creation of these mesons close to the kinematical thresholds in the pp → ppX reaction differs significantly. Using the COSY-11 detection setup we intend to determine whether this difference will also be so significant in the case of the production of these mesons in the proton-neutron scattering. Additionally, the comparison of the pp → ppη′ and pn → pnη′ total cross sections will allow to learn about the production of the η′ meson in the channels of isospin I = 0 and I = 1 and to investigate aspects of the gluonium component of the η′ meson. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The COSY-11 experimental setup is an internal facility installed at the COoler SYnchrotron COSY in Jülich. It allows to investigate meson production in free and quasi-free nucleon-nucleon collisions, eg. pp → pp meson and pd → pspnp meson reactions. Drift chambers and scintillators permit to measure outgoing protons, separated in the magnetic field of the COSY-11 dipole. Neutrons are registered in the neutron modular detector installed downstream from the target. Recently, the experimental setup has been extended with spectator detector, deuteron drift chamber and polarization monitoring system, and since then meson production can be investigated also as a function of spin and isospin of colliding nucleons. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The transverse polarization components of the positrons from the decay of polarized muons have been measured at the Paul Scherrer Institute by annihilating in flight the decay positrons with polarized electrons. The use of a stroboscopic method greatly reduces systematic errors. The energy dependence of the transverse polarization component PT1, which lies in the plane spanned by muon spin and positron momentum, yields the low energy parameter η and thus an improved model-independent value of the Fermi coupling constant. A non-zero value of the transverse component PT2, which is perpendicular to the plane mentioned above, would be the first observation of time reversal violation in a purely leptonic decay. Part of the data (40 × 108 annihilation events) have been evaluated. Both PT1 and PT2, averaged over the positrons’ energy, are consistent with zero with a precision improved by a factor of three as compared with the previous measurement. The preliminary results are = (7 ± 8) × 10-3, = (-1 ± 8) × 10-3 in full agreement with the standard model. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Polarisation observables constitute a powerful tool for establishing the production mechanism of the η meson and for infering the presence of higher partial waves in the final system. Measurements of the proton analysing power for the p→p→ppη reaction have been performed by the COSY-11 group at three different excess energies: Q=10, 37 and 40 MeV. Data at Q=40 MeV indicate that the η meson is probably produced in partial waves higher than s wave. [ABSTRACT FROM AUTHOR]

A comparison of the close-to-threshold total cross sections for the η′ meson production in both the pp→ppη′ and pn→pnη′ reactions should provide insight into the flavour-singlet (perhaps also into gluonium) content of the η′ meson and the relevance of quark-gluon or hadronic degrees of freedom in the creation process. The excitation function for the reaction pp→ppη′ has been already established. At present, experimental investigations of the quasi-free pn→pnX reactions are carried out at the COSY-11 facility using a beam of stochastically cooled protons and the deuteron cluster target. A method of measurement and preliminary results from the test experiments of the pn→pnη reaction are presented in this report. [ABSTRACT FROM AUTHOR]

Measurements of the near threshold Λ and Σ0 production via the pp→pK+Λ/Σ0 reaction at COSY-11 have shown that the Λ/Σ0 cross section ratio exceeds the value at high excess energies (Q ≥ 300 MeV) by an order of magnitude. For a better understanding additional data have been taken between 13 MeV and 60 MeV excess energy. Within the first 20 MeV excess energy a strong decrease of the cross section ratio is observed, with a less steep decrease in the higher excess energy range. A description of the data with a parametrisation including p-Y final state interactions suggests a much smaller p-Σ0 FSI compared to the p-Λ system. [ABSTRACT FROM AUTHOR]

The standard model of electroweak interactions predicts that the positrons from the decay of polarized positive muons are mainly longitudinally polarized. The measurement of the two transverse polarization components of the positron PT1 and PT2 is a sensitive tool to look for contributions from additional, exotic interactions and for the violation of time reversal invariance in this purely leptonic decay. The μPT - experiment at the Paul Scherrer Institute determines the three positron polarization components simultaneously with the same apparatus by making use of three different effects. By examining the temporal dependence of annihilation-in-flight of the decay positrons with polarized electrons a possible non-zero value of the transverse polarization is determined. The phase of this transverse polarization can be measured by making use of the decay asymmetry. Using the dependence of annihilation-in-flight on the angle between electron polarization and positron momentum leads to the determination of the longitudinal polarization which not only completes the measurement of the entire polarization vector but also serves as a sensitivity check. In order to deduce the polarization at the time and location of the muon decay a method based on Monte-Carlo simulations with full spin-dependence implemented is being developed. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

We present an overview of the latest results for interactions of Au+Au ions at centerof-mass energies of √[sup S]NN of 56, 130 and 200 GeV obtained by the PHOBOS collaboration at the Relativistic Heavy Ion Collider (RHIC). These data have allowed us to perform an extensive study of the pseudorapidity density of primary charged particles as a function of incident energy, centrality and pseudorapidity. Our results show a non-trivial evolution of particle densities with both centrality and collision energy, reaching significantly higher values per participating nucleon than at lower energies or in nucleon-nucleon collisions. Further we present results on the azimuthal asymmetry of particle production observed in the √[sup S]NN of 130 GeV data set. The observed strong event anisotropy of V[sup max, sub 2] > 0.06, reaching beyond the value predicted in hadronic cascade models, indicates a closer approach to local thermal equilibration than at lower collision energies. The measured antiparticleparticle ratios of production rates for pions kaons and protons in central Au+Au interactions at √[sup S]NN of 130 GeV are compatible with predictions from statistical models, showing an approach to a baryon free region in mid-rapidity with the increase in collision energy. [ABSTRACT FROM AUTHOR]

The near-threshold production of K[sup +]K[sup -] pairs, as well as of η mesons, has been measured in proton-proton collisions using the COSY-11 facility at the cooler synchrotron COSY. The obtained cross section for the pp→ppK[sup +]K[sup -] reaction at an excess energy of Q=17 MeV represents the first measurement on the K[sup +]K[sup -] production below the &Fgr; meson production threshold. The possible influence of a resonant production via intermediate scalar states f[sub 0](980) and a[sub 0](980) is discussed. The total cross sections for η meson production in the pp→ppη reaction were determined for eight different excess energies in the range from Q=0.5 MeV to Q=5.4 MeV. Inclusion of the η-proton interaction is essential for the description of the energy dependence of the total cross section. The effect of η-proton interaction is also seen in the Dalitz plot from a high statistics measurement at Q=15.4 MeV. The ongoing studies at the COSY-11 facility of η meson production in the pvector p→ppη, pd→[sup 3]Heη and dp→pdη are also presented. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The near threshold total cross section and angular distributions of K[sup +]K[sup -] pair production via the reaction pp → ppK[sup +]K[sup -] have been studied at an excess energy of Q - 17 MeV using the COSY-11 facility at the cooler synchrotron COSY. The obtained cross section as well as an upper limit at an excess energy of Q = 3 MeV represent the first measurements on the K[sup +]K[sup -] production in the region of small excess energies where production via the channel pp → ppφ → ppK[sup +]K[sup -] is energetically forbidden. [ABSTRACT FROM AUTHOR]

The PHOBOS experiment at RHIC has measured the charged-particle density dN/dη at mid-rapidity for central Au+Au collisions at center of mass energies of ...S[sup NN] = 56, and 130 GeV. We deduce that dN/dη = 408±12(stat) ±30(syst) and 555±12(stat)±35(syst) for collision energies of 56 GeV and 130 GeV, respectively. These numbers suggest energy densities that are some 70% higher than have been achieved in any heavy-ion collisions previously studied, and also 25-40% higher than nucleon-nucleon collisions at comparable center of mass energies. [ABSTRACT FROM AUTHOR]

In the standard model (SM) of electroweak interactions the positron from the decay of polarized positive muons is mainly longitudinally polarized. The measurement of the two transverse polarization components, therefore, is a sensitive tool for contributions from additional, exotic, interactions. The energy dependence of the transverse polarization component P[sub T[sub 1]], which lies in the plane spanned by muon-spin and positron momentum, yields the low energy parameter η and thus an improved mode-independent value of the Fermi coupling constant. A non-zero value of the transverse component P[sub T[sub 2]], which is perpendicular to the above mentioned plane, would be the first observation of time reversal violation in a purely leptonic decay. The μ[sub P[sub T]] experiment at the Paul Scherrer Institute determines the three polarization components simultaneously with the same apparatus by making use of three different reactions (spatial and temporal dependence of annihilation-in-flight with polarized electrons as well as muon decay asymmetry). The use of a stroboscopic method greatly reduces systematic errors. The measurement of the longitudinal polarization serves mainly as a test of the sensitivity of the apparatus, while the measurement of the two transverse components will improve the current experimental limits. The preliminary results are P[sub T[sub 1]] = (7 ±13) x 10[sup -3], P[sub T[sub 2]] = (19±13) x 10[sup -3]. [ABSTRACT FROM AUTHOR]

n the standard model (SM) of electroweak interactions the positron from the decay of polarized positive muons is mainly longitudinally polarized. However the model also predicts a small transverse polarization component P[sub T[sub 1]], which lies in the plane spanned by muon-spin and positron momentum. Interference with additional, scalar couplings would result in substantial values for P[sub T[sub 1]] as well as in a non-zero value of the transverse component P[sub T[sub 2]] which is perpendicular to the above mentioned plane. A nonzero component P[sub T[sub 2]], proportional to the imaginary part of a possible scalar coupling, would be the first observation of time reversal violation in a purely leptonic decay. Measuring P[sub T[sub 1]], which is proportional to the real part, amounts to a model independent determination of the Fermi-coupling constant. The μ[sub P[sub T]] experiment [1] at the Paul Scherrer Institute will improve the current experimental limits P[sub T[sub 1]] = (16 ± 22) x 10[sup -3], P[sub T[sub 2]] = (7 ± 23) x 10[sup -3] by almost one order of magnitude. First preliminary results of the experiment are given. [ABSTRACT FROM AUTHOR]

Close-to-threshold data on the elementary kaon and antikaon production channels in the proton-proton interaction have been taken using the COSY-11 installation at the cooler synchrotron COSY Ju¨lich. The experimental technique applied at the internal COSY-11 facility—designed for meson production studies at small excess energies—is outlined. The threshold excitation functions for the kaon-hyperon production via the reactions pp→pK[sup +]Λ and pp→pK[sup +]Σ[sup 0] are presented. The magnitude of the production amplitudes is compared at equal excess energies and physical implications of the observed Σ[sup 0] suppression in the threshold region are discussed. In addition, within a Dalitz plot analysis the spin-averaged S-wave scattering parameters could be extracted for the Λ-p channel. With the possibility of detecting all final state particles the elementary antikaon production in the reaction pp→ppK[sup +]K[sup -] has been investigated. Results on the exclusive total cross section fix the scale of the strangeness dissociation into two kaons. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The COSY-11 collaboration has measured the total cross section for the pp→ppη[sup ′] and pp→ppη reactions in the excess energy range from Q=1.5 MeV to Q=23.6 MeV and from Q=0.5 MeV to Q=5.4 MeV, respectively. Measurements have been performed with the total luminosity of 73 nb-1 for the pp→ppη reaction and 1360 nb-1 for the pp→ppη[sup ′] one. Recent results are presented and discussed. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Pion and η production on the deuteron are studied at energies in the vicinity of the absolute threshold. The data are expected to be sensitive to high momentum components in the deuteron wavefunction as well as to two step processes. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]