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Since the first cyclotron beam fifty years ago, the Texas A&M Cyclotron Institute has functioned as a university-based laboratory. Over the past two decades it has been funded by the U.S. Department of Energy, the State of Texas, the Welch Foundation, and commercial sale of beam-time. The first accelerator is a conventional isochronous cyclotron modeled after the 88″ cyclotron at the Lawrence Berkeley Laboratory. It arose from a proposal funded by the U.S. Atomic Energy Commission, the R. A. Welch Foundation (a private foundation headquartered in Houston), and the State of Texas and continued to operate from 1967 to 1987. After recommissioning in 2007 as a higher-field K150 machine, it is still in operation. The K500 cyclotron, funded in 1980 by the Welch Foundation and Texas A&M University and modeled after the Michigan State NSCL K500 cyclotron, is a superconducting isochronous cyclotron whose first beam was extracted in 1988.

Cluster formation is a fundamental aspect of the equation of state (EOS) of warm and dense nuclear matter such as can be found in supernovae (SNe). Similar matter can be studied in heavy-ion collisions (HIC). We use the experimental data of Qin et al. [Phys. Rev. Lett. 108, 172701 (2012)] to test calculations of cluster formation and the role of in-medium modifications of cluster properties in SN EOSs. For the comparison between theory and experiment we use chemical equilibrium constants as the main observables. This reduces some of the systematic uncertainties and allows deviations from ideal gas behavior to be identified clearly. In the analysis, we carefully account for the differences between matter in SNe and HICs. We find that, at the lowest densities, the experiment and all theoretical models are consistent with the ideal gas behavior. At higher densities ideal behavior is clearly ruled out and interaction effects have to be considered. The contributions of continuum correlations are of relevance in the virial expansion and remain a difficult problem to solve at higher densities. We conclude that at the densities and temperatures discussed mean-field interactions of nucleons, inclusion of all relevant light clusters, and a suppression mechanism of clusters at high densities have to be incorporated in the SN EOS., 20 pages, 15 figures, v2: matches published version, only minor editorial corrections

The diagnostics of particle flows in Inertial Confinement Fusion experiments is a delicate issue, due to the fast timescales and to the strong radiative electromagnetic contributions. This makes the discrimination of the different particles produced by the laser-plasma interaction not trivial, and requires the use of several diagnostic techniques. We describe here the diagnostics improvement in the ABC facility. They will provide more detailed analysis of microwave fields and particles originating from the interaction of laser with targets foreseen for future experiments. © 2013 Euratom-ENEA Association.

We present a novel way of determining the plasma temperature in a laser-cluster fusion experiment on the Texas Petawatt laser, which uses the ratio of the 2.45 MeV neutron and 14.7 MeV proton yields.

Multifragmentation, following the formation of toroidal and bubble nuclei, is observed with an improved Boltzmann-Uehling-Uhlenbeck (BUU) model for central {sup 92}Mo {plus} {sup 92}Mo collisions. Guided by our BUU model, we propose two signatures: (1) because of the geometries of bubbles and toroids and because of the cold breakup at low temperatures, we predict enhanced cross sections for fragments with nearly-equal masses at small center-of-mass energies. (2) the coplanarity of these nearly-equal fragments could carry important information concerning the geometry of the sources. This in turn, could provide information about the stiffness of the equation of state.

We present spectra of charged pions and protons in 0–10% central Au + Au collisions at s N N = 200 GeV at mid-rapidity ( y = 0 ) and forward pseudorapidity ( η = 2.2 ) measured with the BRAHMS experiment at RHIC. The spectra are compared to spectra from p + p collisions at the same energy scaled by the number of binary collisions. The resulting nuclear modification factors for central Au + Au collisions at both y = 0 and η = 2.2 exhibit suppression for charged pions but not for (anti-) protons at intermediate p T . The p ¯ / π − ratios have been measured up to p T ∼ 3 GeV / c at the two rapidities and the results indicate that a significant fraction of the charged hadrons produced at intermediate p T range are (anti-) protons at both mid-rapidity and η = 2.2 .

Measurements of particle emission, linear momentum transfer and angular momentum transfer have been used to explore reaction mechanisms in the intermediate energy range where qualitatively different nuclear processes may be observable. The current status of our understanding of heavy ion reaction mechanisms with projectiles having velocities comparable to the velocity of sound and the Fermi velocity is summarized.

Light charged particles and nuclei (1⩽Z⩽8) have been detected in a large forward plastic multidetector (3° < θ

Mica track detectors were used to detect recoil nuclei from the reactions of $^{12}\mathrm{C}$, $^{16}\mathrm{O}$, and $^{20}\mathrm{Ne}$ projectiles with Cu, Ag, Au, and Bi targets. The observed track-length distributions and angular distributions together with detector-threshold information indicate that the observed recoils result from complete fusion of the target and projectile nuclei. The cross section ${\ensuremath{\sigma}}_{\mathrm{CF}}$ for the complete fusion mechanism is found to be well below the total-reaction cross section ${\ensuremath{\sigma}}_{R}$ at the higher projectile energies. A sharp-cutoff model is employed to extract values of ${J}_{\mathrm{crit}}$, the maximum angular momentum of the compound nuclei formed in complete-fusion reactions. Using those values, complete-fusion cross sections are calculated as a function of the mass of the complete-fusion product for reactions induced by$\phantom{\rule{0ex}{0ex}}^{16}\mathrm{O}$, $^{20}\mathrm{Ne}$, and $^{40}\mathrm{Ar}$. Assuming only first-chance fission, the ratio $\frac{{\ensuremath{\Gamma}}_{f}}{{\ensuremath{\Gamma}}_{n}}$ has been calculated for the system $^{197}\mathrm{Au}$+$^{16}\mathrm{O}$\ensuremath{\rightarrow}$^{213}\mathrm{Fr}$*.