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A detector consisting of four p-i-n silicon pad structures of size 6 × 6 mm2 and thickness 300 μm was developed for the rapid monitoring of carbon ion beam quality at the Temporary Radiobiology Facility at the Institute for High Energy Physics (TRBF IHEP) by measuring event-by-event energy release on passage of charged particles (ions) through it. This articles describes the detector design and the method used for identifying contaminants in the beam of carbon nuclei. The charge composition of the ion beam of the TRBF IHEP calculated using the amplitude spectra of signals from the p-i-n structures is presented.

The results obtained by estimating the contribution of 8Be and 9B nuclei to the coherent dissociation of 10C, 10B, and 12C relativistic nuclei in nuclear track emulsions (“white” stars) are presented. The selection of white stars accompanied by 9B leads to a distinct peak appearing in the distribution of the excitation energy of 2α2p ensembles and having a maximum at 4.1 ± 0.3 MeV. A 8Be nucleus manifests itself in the coherent-dissociation reaction 10B → 2He + H with a probability of (25 ± 5)%, (14 ± 3)% of it being due to 9B decays. The ratio of the branching fractions of the 9B + n and 9Be + p mirror channels is estimated at 6 ± 1. An analysis of the relativistic dissociation of 12C nuclei in a nuclear track emulsion revealed nine 3α events corresponding to the Hoyle state.

Production of ensembles of $\alpha$-particle triples associated with the Hoyle state (the second excited state of the ${}^{12}$C nucleus) in peripheral dissociation of relativistic ${}^{12}$C nuclei is studied. Stacks of nuclear track emulsion pellicles exposed to ${}^{12}$C with an energy from hundreds MeV to a few GeV per nucleon serve as the material for studies. The Hoyle state decays are reconstructed via measurement of emission angles of $\alpha$ particles with the precision sufficient for identification of the unstable ${}^{8}$Be nucleus. The estimate of the contribution of Hoyle's state to the ${}^{12}$C $\to$ 3$\alpha$ dissociation is 10-15\%., Comment: 12 pages, 11 figures, 1 table

The stages of development and the current status of the versatile “Spectrometer with a Vertex Detector” setup designed for physics experiments at the U-70 accelerator of the Institute for High Energy Physics (Protvino) is described. The main detectors of the setup are the vertex detector based on silicon microstrip detectors, the wide-aperture magnetic spectrometer based on multiwire proportional chambers, and the lead-glass hodoscope γ detector. In the setup, there is a fast two-level trigger system for selecting required particle interactions. The key characteristics of the setup systems are presented, and the physical results obtained on it are briefly listed.

A matrix gallium-arsenide detector for roentgenography and nondestructive monitoring is described in this work. The detector contains 128 × 128 sensitive elements with 50-μm pitch, an analog multiplexor, and a system for information acquisition. The detector is intended for use in low- or medium-dose medical X-ray apparatuses. It can also be used for nondestructive defectoscopy.

Experimental and theoretical studies of direct photon production in hadronic collisions essentially expand our insights in multiparticle production mechanisms. These photons are useful probes to investigate nuclear matter at all stages of the interaction. Soft photons play a particular role in these studies. Until now we have no explanation for the experimentally observed excess of soft photons. These photons have low transverse momenta \( p_{T} < 0.1\) GeV/c, \( \vert x\vert < 0.01\) . In this domain their yield exceeds the theoretical estimates by 5-8 times. The registration of soft photons at Nuclotron (LHEP, JINR) has been carried out by the electromagnetic calorimeter built by the SVD-2 Collaboration. Soft photon electromagnetic calorimeter was tested at U-70, IHEP (Protvino). For the first time the soft photon yield at interactions of 3.5A GeV/c per nucleon deuterium and lithium beams has been measured. The obtained energy spectra confirm the increased yield of soft photons with their energy less than 50MeV (in the laboratory system) in comparison with theoretical predictions and agree with previous experiments at high-energy interactions. It is planned to continue soft photon study at the future accelerator complex NICA with heavy-ion beams.

Study of production of ensembles of alpha-particle triples associated with the Hoyle state (the second excited state 0 + 2 of the 12 C nucleus) in peripheral dissociation of relativistic 12 C nuclei is started. Stacks of pellicles of nuclear track emulsion exposed to 12 C of energy from hundreds MeV to few GeV per nucleon serve as the material of the study. The Hoyle state decays are reconstructed via measurements of emission angles of α-particles with accuracy that allows one to identify the unstable 8 Be nucleus. A role in the Hoyle state of alpha-particle bonds corresponding to 8 Be is determined.

First results of a soft photon yield in nucleus-nuclear interactions at 3.5 GeV per nucleon are presented. These photons have been registered at Nuclotron (LHEP, JINR) by an electromagnetic calorimeter built in the SVD Collaboration. The obtained spectra confirm the excess yield in the energy region less than 50 MeV in comparison with theoretical predictions and agree with previous experiments at high-energy interactions., 5 pages, 3 figures, presented at the International Conference on New Photo-detectors July 6-9, 2015, Moscow, Troitsk, Russia