Fragmentation of light nuclei by intermediate energy photons

New data on the fragmentation of carbon nuclei by photons with energies from 800 to 1500 MeV, obtained in the collaboration GRAAL, are presented. These data include the yields of heavier fragments than nucleons. Comparison of new results with literature data, obtained with real and virtual photons in reactions with electrons and relativistic ions (Coulomb dissociation) is done using a general approach in frame of the Weizsäcker–Williams model. Possible reasons for the observed differences between them are discussed.     

The Fixed Target Experiment for Studies of Baryonic Matter at the Nuclotron (BM@N)

BM@N (Baryonic Matter at Nuclotron) is the first experiment to be realized at the NICA-Nuclotron accelerator complex. The aim of the BM@N experiment is to study relativistic heavy ion beam interactions with fixed targets. The BM@N setup, results of Monte Carlo simulations, and the BM@N experimental program are presented.     

The upgrade of endcap CMS muon system

The configuration and composition of the CMS muon system are presented. The paper is focused on cathode strip chambers (CSC) used as the endcap muon system detectors. The goals and objectives of the endcap muon system upgrade are formulated. The main results of works accomplished for the ME1/1 CSCs upgrade and the new ME4/2 muon station construction during the LHC Long Shutdown-1 (2013–2014) are presented. The improved performances of the endcap muon system are shown using experimental data obtained after the upgrade (Run2 data).     

Nuclear polarization of molecular hydrogen recombined on a non-metallic surface

The nuclear polarization of molecules formed by recombination of nuclear polarized H atoms on the surface of a storage cell initially coated with a silicon-based polymer has been measured by using the longitudinal double-spin asymmetry in deep-inelastic positron-proton scattering. The molecules are found to have a substantial nuclear polarization, which is evidence that initially polarized atoms retain their nuclear polarization when absorbed on this type of surface.Received: 15 December 2003, Published online: 24 February 2004PACS: 29.25.Pj Polarized and other targets - 34. Atomic and molecular collision processes and interactions - 39.10. + j Atomic and molecular beam sources and techniques - 13.88. + e Polarization in interactions and scattering     

Hard photon production in the reaction Xe+Sn at 50 A MeV

The first results of the analysis of the TAPS experiment performed at GANIL in 1998 are presented. First, the pre-analysis of a typical TAPS experiment (data storage, energy calibration, time alignment, time monitorings and pulse-shape analysis) is described. Secondly, a preliminary inclusive hard photon spectrum of the reaction ¹²⁹Xe+¹¹²Sn at 50 A MeV is shown. The hard photon spectrum exhibits a good agreement with the systematics collected by the TAPS collaboration in the last KVI experiments.     

Investigations into beam monitors at the AEg ̄ IS experiment

Detailed diagnostic of antiproton beams at low energies is required for essentially all experiments at the Antiproton Decelerator (AD), but will be particularly important for the future Extra Low ENergy Antiproton ring (ELENA) and its keV beam lines to the different experiments. Many monitors have been successfully developed and operated at the AD, but in particular beam profile monitoring remains a challenge. A dedicated beam instrumentation and detector test stand has recently been setup at the AE \(\bar {g}\) IS experiment (Antimatter Experiment: Gravity, Interferometry, Spectroscopy). Located behind the actual experiment, it allows for parasitic use of the antiproton beam at different energies for testing and calibration. With the aim to explore and validate different candidate technologies for future low energy beam lines, as well as the downstream antihydrogen detector in AE \(\bar {g}\) IS, measurements have been carried out using Silicon strip and pixel detectors, a purpose-built secondary emission monitor and emulsions. Here, results from measurements and characterization of the different detector types with regard to their future use at the AD complex are presented.     

Results from the CMS collaboration on the search of heavy dilepton and diphoton resonances

A survey of the results on the search of new heavy resonances decaying into muon, electron, or photon pairs in the CMS experiment at proton beams of the LHC in the run of 2015 for the total center of mass energy √s = 13 TeV is presented. The limits for heavy resonance production cross sections are set. Excess of diphoton events in the region of mass spectra near 750 GeV with a local statistical significance of 3.4 σ and a global statistical significance of 1.6 σ is observed.     

57Fe Emission Mössbauer Study on Gd3Ga5O12 implanted with dilute57Mn

⁵⁷Fe emission Mössbauer spectroscopy has been applied to study the lattice location and properties of Fe in gadolinium gallium garnet Gd₃Ga₅O₁₂ (GGG) single crystals in the temperature interval 300 – 563 K within the extremely dilute (<10^?4 at.%) regime following the implantation of⁵⁷Mn (T¹_/2= 1.5 min.) at ISOLDE/CERN. These results are compared with earlier Mössbauer spectroscopy study of Fe-doped gadolinium gallium garnet Gd₃Ga₅O₁₂(GGG), with implantation fluences between 8×10¹⁵ and 6×10¹⁶ atoms cm^?2. Three Fe components are observed in the emission Mössbauer spectra: (i) high spin Fe²⁺ located at damage sites due to the implantation process, (ii) high spin Fe³⁺ at substitutional tetrahedral Ga sites, and (iii) interstitial Fe, probably due to the recoil imparted on the daughter^57?Fe nucleus in the β^? decay of⁵⁷Mn. In contrast to high fluence⁵⁷Fe implantation studies the Fe³⁺ ions are found to prefer the tetrahedral Ga site over the octahedral Ga site. No annealing stages are evident in the temperature range investigated. Despite the very low concentration, high-spin Fe³⁺ shows fast spin relaxation, presumably due to an indirect interaction between nearby gadolinium atoms.     

The NA62 experiment at CERN

The goal of the NA62 experiment at CERN is to collect O(100) events of the ultrarare K\(^{+}\rightarrow \pi ^{+}\nu \bar {\nu }\) decay in two years. After a long R&D phase and a successful pilot run in 2014, the first data-taking phase took place in 2015. In this paper the importance of the experiment’s physics goal, as well as the experimental solutions adopted in order to attain it, will be reviewed.