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The region of $N\approx Z\approx 40$ has long been associated with strongly deformed nuclear configurations. The presence of this strong deformation was recently confirmed through lifetime measurements in $N\approx Z$ Sr and Zr nuclei. Theoretically, however, these nuclei present a challenge due to the vast valence space required to incorporate all deformation driving interactions. Recent state-of-the-art predictions indicate a near axial prolate deformation for $N=Z$ and $N=Z+2$ nuclei between $N=Z=36$ and $N=Z=40$. In this work we investigate the shores of this island of deformation through a sub-barrier Coulomb excitation study of the $N=Z+4$ nucleus, \textsuperscript{80}Sr. Extracting a spectroscopic quadrupole moment of $Q_s(2^+_1) = 0.45^{+0.83}_{-0.88}$~eb, we find that \textsuperscript{80}Sr is inconsistent with significant axial prolate deformation. This indicates that the predicted region of strong prolate deformation around $N=Z=40$ is tightly constrained to the quartet of nuclei: \textsuperscript{76,78}Sr and \textsuperscript{78,80}Zr., Comment: Submitted to Physics Letters B

We have performed the first direct measurement of the 83Rb(p,g) radiative capture reaction cross section in inverse kinematics using a radioactive beam of 83Rb at incident energies of 2.4 and 2.7 A MeV. The measured cross section at an effective relative kinetic energy of Ecm = 2.393 MeV, which lies within the relevant energy window for core collapse supernovae, is smaller than the prediction of statistical model calculations. This leads to the abundance of 84Sr produced in the astrophysical p process being higher than previously calculated. Moreover, the discrepancy of the present data with theoretical predictions indicates that further experimental investigation of p-process reactions involving unstable projectiles is clearly warranted., Comment: 6 pages, 4 figures, published in Physical Review Letters

We investigate various aspects of the "weighted" greedy algorithm with respect to a Schauder basis. For a weight w, we describe w-greedy, w-almost-greedy and w-partially-greedy bases, and show some properties of w-semi-greedy bases. To achieve these goals, we introduce and study the w-Property (A)., Comment: 23 pages

Radial scans of main rings obtained at a variety of phase angles, local times and ring opening angles. Circular focal plane 1 slowly scanned across rings. Radial resolution approx. 2500 km. Temperatures decrease with increasing phase angle for all main rings. Rough estimate of particle spin period for B ring particle is P > 1.8 hours

We observed slected mutual occultations of Jupiter's satellites in 1990-1991 and we used the occultation profiles to constrain the areal distribution of selected spectrally active compounds on Io's surface.

The surface properties of Triton were investigated using data from the ground-based and Voyager photopolarimeter subsystem (PPS) observations of Triton's phase curve. The results indicate that Triton has a high single-scattering albedo (0.96 +/-0.01 at 0.75 micron) and an unusually compacted surface, possibly similar to that of Europa. Results also suggest that Triton's single-particle phase function and the macroscopically rough character of its surface are similar to those of most other icy satellites.

The spectral geometric albedo and the bolometric Bond albedo of Triton are calculated using data from the Voyager spacecraft photopolarimeter and science experiments. The geometric albedo is not inconsistent with the presence of a weak absorption feature in Triton's spectrum near 0.75 micron. The bolometric Bond albedo (0.65) is consistent with the 38 K daytime surface temperature of Triton. The results are also in agreement with the 37.5 K temperature of nitrogen at an infrared basal pressure of 14 microbar.