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For the target-reactor coupling calculation in Accelerator Driven Sub-critical System (ADS). We developed the proton-neutron transport code IMPC-MC1.0 by embedding the Intra-Nuclear Cascade model of Liege (INCL++5.1) and abrasion-ABLAtion model (ABLA) fission-evaporation de-excitation model into the OpenMC (v0.12.0). To verify the code, the Brookhaven National Laboratory - Alternating Gradient Synchrotron (BNL-AGS) experimental benchmark was investigated. And the IMPC-MC1.0 results for neutron yield of the Pb and W target are in perfect agreement with those of measured values. Moreover, the simulated neutron leakage spectra are consistent with MCNPX and FLUKA calculations. Then the ADS target models filled with different materials were simulated, the results of neutron yield, energy spectrum are reasonable when compared with LAHET calculation. Finally, the homogenized Japan Atomic Energy Agency (JAEA) 800 MW lead-bismuth cooled target-reactor model was verified for ADS application. The related results are reliable when compared with the those calculated by MCNPX.

The beam injection system of the Relativistic Heavy Ion Collider (RHIC) is the last section of the beam transfer line which transports the beam from the Alternating Gradient Synchrotron (AGS) to RHIC and comes under the acronym AtR (AGS to RHIC) ( https://ieeexplore.ieee.org/document/749599 , https://ieeexplore.ieee.org/abstract/document/749594 ). The Lambertson septum magnet is one of the magnetic elements of the RHIC injection system ( https://ieeexplore.ieee.org/abstract/document/749594 ). This paper presents results from the 2D and 3D electromagnetic design of the RHIC Lambertson septum magnet which has unique design features to minimize the magnetic field at the circulated beam region including the fringe field regions at the entrance and exit of the magnet.

To investigate the chiral magnetic effect, 96Zr and 96Ru beams were accelerated at the relativistic heavy ion collider (RHIC) during Run-18 at Brookhaven National Laboratory. The 96Zr beam was provided from the electron beam ion source (EBIS) injector, which consists of a laser ion source, an EBIS high charge state ion breeder, a 300 keV/u radio frequency quadrupole, and a 2 MeV/u interdigital H type drift tube linear accelerator (IH-DTL). The natural abundance of 96Zr is only 2.8% with about 50% of 90Zr. To obtain a sufficient beam current, Zr material enriched to about 60% of 96Zr was used. The only available form of the enriched material was zirconium oxide (ZrO2) powder, which was not well suited for a laser ion source target. We studied and established a sintering technique of the ZrO2 powder to make a solid sample which could be installed into the laser ion source. The singly charged Zr was produced in a laser ablation plasma, extracted, and delivered to the EBIS to be ionized further to 96Zr16+. We optimized the laser irradiation condition, the EBIS confinement time, and transport through the RF linacs to maximize the performance of the injector. The total number of shots provided from the laser ion source for injection into the EBIS was 489 910. The EBIS facility provided a 192 MeV stable beam of 96Zr16+ ions to the booster ring of alternating gradient synchrotron (AGS) for further acceleration and stripping in the AGS/RHIC complex, allowing for successful data acquisition at the Solenoidal Tracker at the RHIC.

The p-carbon polarimeter working in the dp/p Coulomb Nuclear Interference (CNI) region has been used in the Brookhaven Alternating Gradient Synchrotron (AGS ) for many years. It has gone though several upgrades to improve its performance. With targets sweeping through beam vertically and horizontally, the polarimeter can provide polarization profile information. To preserve polarization, a pair of horizontal tune jump quads have been used to overcome horizontal intrinsic resonances. Recently, the polarization measurement on the energy ramp has been used to decide the beam energy as function of time on the ramp. This paper summarize the recent operation experience of AGS p-carbon CNI polarimeter.

The main aim of the relativistic heavy-ion experiment is to create extremely hot and dense matter and study the QCD phase structure. With this motivation, experimental program started in the early 1990s at the Brookhaven Alternating Gradient Synchrotron (AGS) and the CERN Super Proton Synchrotron (SPS) followed by Relativistic Heavy Ion Collider (RHIC) at Brookhaven and recently at Large Hadron Collider (LHC) at CERN. These experiments allowed us to study the QCD matter from center-of-mass energies (sNN) 4.75 GeV to 2.76 TeV. Theϕmeson, due to its unique properties, is considered as a good probe to study the QCD matter created in relativistic collisions. In this paper we present a review on the measurements ofϕmeson production in heavy-ion experiments. Mainly, we discuss the energy dependence ofϕmeson invariant yield and the production mechanism, strangeness enhancement, parton energy loss, and partonic collectivity in nucleus-nucleus collisions. Effect of later stage hadronic rescattering on elliptic flow (v2) of proton is also discussed relative to corresponding effect onϕmesonv2.

Widths of the rapidity distributions of various identified hadrons generated with the UrQMD-3.4 event generator at all the Super Proton Synchrotron (SPS) energies have been presented and compared with the existing experimental results. An increase in the width of the rapidity distribution of $\mathrm{\ensuremath{\Lambda}}$ could be seen with both Monte Carlo (MC) and experimental data for the studied energies. Using MC data, the study has been extended to Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies. A similar jump, as observed in the plot of rapidity width versus rest mass at Alternating Gradient Synchrotron (AGS) and all SPS energies, persists even at RHIC and LHC energies, confirming its universal nature from AGS to the highest LHC energies. Such observation indicates that pair production may not be the only mechanism of particle production at the highest LHC energies. However, with MC data, the separate mass scaling for mesons and baryons is found to exist even at the top LHC energy.

The compressed baryonic matter (CBM) experiment planned at the Facility for Antiproton and Ion Research (FAIR) will provide a major scientific effort for exploring the properties of strongly interacting matter in the high baryon density regime. One of the important goals behind such experiment is to precisely determine the equation of state (EOS) for the strongly interacting matter at extremely large baryon density. In this paper, we have used some successful models for RHIC and LHC energies to predict different particle ratios and the total multiplicity of various hadrons in the CBM energy range, that is, from 10 A GeV to 40 A GeV lab energies, which corresponds to 4.43 A GeV and 8.71 A GeV center-of-mass energies. Our main emphasis is to estimate the strange particles enhancement as well as an increase in the net baryon density at CBM experiment. We have also compared the model results with the experimental data obtained at alternating gradient synchrotron (AGS) and super proton synchrotron (SPS).

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory is the only collider in the world to collide polarized protons. In order to maximize the polarization of the proton beam in RHIC, it is critical that the polarization is measured during the acceleration process. This is accomplished with Coulomb nuclear interference (CNI) polarimeters in the Alternating Gradient Synchrotron (AGS) and RHIC. The targets for the CNI polarimeters are carbon micro-ribbons that are optimized in width for the detectors. The targets used in the AGS CNI polarimeter are 4 μg/cm2 thick (25–30 nm) and 50 mm long. The width of these targets is either 75, 125 or 250 μm. The targets used in the RHIC CNI polarimeter are the same thickness but only 25 mm long and

Experimental results of the rapidity spectra of protons and net-protons (protons minus antiprotons) emitted in gold-gold (Au-Au) and lead-lead (Pb-Pb) collisions, measured by a few collaborations at the alternating gradient synchrotron (AGS), super proton synchrotron (SPS), and relativistic heavy ion collider (RHIC), are described by a three-source distribution. The values of the distribution width $\sigma_C$ and contribution ratio (relative contribution) $k_C$ of the central rapidity region, and the distribution width $\sigma_F$ and rapidity shift $\Delta y$ of the forward/backward rapidity regions, are then obtained. The excitation function of $\sigma_C$ increases generally with increase of the center-of-mass energy per nucleon pair $\sqrt{s_{NN}}$. The excitation function of $\sigma_F$ shows a saturation at $\sqrt{s_{NN}}=8.8$ GeV. The excitation function of $k_C$ shows a minimum at $\sqrt{s_{NN}}=8.8$ GeV and a saturation at $\sqrt{s_{NN}}\approx 17$ GeV. The excitation function of $\Delta y$ increase monotonously with $\ln \sqrt{s_{NN}}$ in the considered energy range., Comment: 19 pages, 8 figures, The European Physical Journal A, accepted

A novel polarization technique had been successfully implemented for the Relativistic Heavy Ion Collider (RHIC) polarized H(-) ion source upgrade to higher intensity and polarization. In this technique, a proton beam inside the high magnetic field solenoid is produced by ionization of the atomic hydrogen beam (from external source) in the He-gaseous ionizer cell. Further proton polarization is produced in the process of polarized electron capture from the optically pumped Rb vapor. The use of high-brightness primary beam and large cross sections of charge-exchange cross sections resulted in production of high intensity H(-) ion beam of 85% polarization. The source very reliably delivered polarized beam in the RHIC Run-2013 and Run-2015. High beam current, brightness, and polarization resulted in 75% polarization at 23 GeV out of Alternating Gradient Synchrotron (AGS) and 60%-65% beam polarization at 100-250 GeV colliding beams in RHIC.