The ${}^{17}\mathrm{F}(p,\gamma {)}^{18}\mathrm{Ne}$ reaction is important in stellar explosions, but its rate has been uncertain because of an expected $3^{+}$ state in ${}^{18}\mathrm{Ne}$ that has never been conclusively observed. This state would provide a strong $\ell =0\mathrm{}$ resonance and, depending on its excitation energy, could dominate the stellar reaction rate. We have observed this missing $3^{+}$ state by measuring the ${}^1\mathrm{H}{(}^{17}\mathrm{F},p{)}^{17}\mathrm{F}$ excitation function with a radioactive ${}^{17}\mathrm{F}$ beam at the ORNL Holifield Radioactive Ion Beam Facility. We find that the state lies at a center-of-mass energy of $E_r=599.8\mathrm{}\pm 1{.5}_{\mathrm{stat}}\pm {2.0}_{\mathrm{sys}}\mathrm{keV}$ ( $E_x=4523.7\mathrm{}\pm 2.9\mathrm{keV}$) and has a width of $\Gamma =18\mathrm{}\pm 2_{\mathrm{stat}}\pm 1_{\mathrm{sys}}\mathrm{keV}$.

The breakup of ${}^{12}\mathrm{Be}$ into ${}^6\mathrm{He}{+}^6\mathrm{He}$ and ${}^4\mathrm{He}{+}^8\mathrm{He}$ has been studied using a 378 MeV ${}^{12}\mathrm{Be}$ beam inelastically excited by ${}^{12}\mathrm{C}$ and $({\mathrm{CH}}_2{)}_n$ targets. The measurements indicate that breakup occurs from rotational states in the 10 to 25 MeV excitation energy interval, with spins in the range of $4ħ$ to $8ħ$. The inferred moment of inertia is consistent with the cluster decay of an exotic molecular structure in ${}^{12}\mathrm{Be}$, which may be associated with an $\alpha -4n-\alpha$ cluster configuration.

The ground-state band of the $Z=102\mathrm{}$ isotope ${}^{254}\mathrm{No}$ has been identified up to spin 14, indicating that the nucleus is deformed. The deduced quadrupole deformation, $\beta =0.27\mathrm{}$, is in agreement with theoretical predictions. These observations confirm that the shell-correction energy responsible for the stability of transfermium nuclei is partly derived from deformation. The survival of ${}^{254}\mathrm{No}$ up to spin 14 means that its fission barrier persists at least up to that spin.

Several approaches to QCD with two massless quarks at finite temperature $T$ and baryon chemical potential $\mu$ suggest the existence of a tricritical point on the boundary of the phase with spontaneously broken chiral symmetry. In QCD with massive quarks there is then a critical point at the end of a first order transition line. We discuss possible experimental signatures of this point, which provide information about its location and properties. We propose a combination of event-by-event observables, including suppressed fluctuations in $T$ and $\mu$ and, simultaneously, enhanced fluctuations in the multiplicity of soft pions.

Breakup temperatures in central collisions of ${}^{197}\mathrm{Au}{+}^{197}\mathrm{Au}$ at bombarding energies $E/A=50\mathrm{}$ to 200 MeV were determined with two methods. Isotope temperatures, deduced from double ratios of hydrogen, helium, and lithium isotopic yields, increase monotonically with bombarding energy from 5 to 12 MeV, in qualitative agreement with a scenario of chemical freeze-out after adiabatic expansion. Excited-state temperatures, derived from yield ratios of states in ${}^4\mathrm{He}$, ${}^{5,6}\mathrm{Li}$, and ${}^8\mathrm{Be}$, are about 5 MeV, independent of the projectile energy, and seem to reflect the internal temperature of fragments at their final separation from the system.

We report on a measurement of the ${}^{44}\mathrm{Ti}$ half-life aimed at lowering existing systematic uncertainties in this value, which is important to astrophysics. The half-life was measured by following the decay of ${}^{44}\mathrm{Ti}$ relative to ${}^{60}\mathrm{Co}$ for about 5 yr and the measurements were performed independently in three laboratories—Argonne, Jerusalem, and Torino. We suggest to combine our result, $59.0\pm 0.6$ yr, with the one from the accompanying Letter by Görres et al., $60.3\pm 1.3$ yr, to obtain a current “best value” for the half-life of ${}^{44}\mathrm{Ti}$ of $59.2\pm 0.6$ yr ( $1\sigma$ error).

Recent measurements of galactic radioactivity with the Compton Gamma Ray Observatory reported ${}^{44}\mathrm{Ti}$ activity from the supernova remnant Cassiopeia A. The absolute amount of ${}^{44}\mathrm{Ti}$ provides a stringent test for current supernova models. The main uncertainty is presently the half-life of ${}^{44}\mathrm{Ti}$. We report a new measurement of the half-life of ${}^{44}\mathrm{Ti}$ applying a novel technique using a mixed radioactive ion beam containing ${}^{44}\mathrm{Ti}$ as well as ${}^{22}\mathrm{Na}$ ions. This method allows the reliable determination of the half-life of ${}^{44}\mathrm{Ti}$ with high accuracy, $t_{1/2}=(60.3\pm 1.3)\mathrm{yr}$. The ${}^{44}\mathrm{Ti}$ abundance determined for Cassiopeia A with this half-life agrees with theoretical predictions within the observational uncertainties.