Interpolation of subcouples and quotient couples

We extend recent results by Pisier onK-subcouples, i.e. subcouples of an interpolation couple that preserve theK-functional (up to constants) and corresponding notions for quotient couples. Examples include interpolation (in the pointwise sense) and a reinterpretation of the Adamyan-Arov-Krein theorem for Hankel operators. This work was done at the Mittag-Leffler Institute. I am particularly grateful to Richard Rochberg for helpful discussions.     

Decay of63Zn

Investigation of the 38.8 min decay of⁶³Zn has resulted in 31 gamma-ray transitions in⁶³Cu. New levels not earlier reported inΒ ⁺-decay of⁶³Zn, but found in nuclear reactions, are suggested at 2,010.9 and 3,101 keV. It is assumed that the excited core model generates a multiplet of levels at 669.75 keV (1/2^?), 962.1 keV (5/2^?), 1,327.1 keV (7/2^?) and 1,546.6 keV (3/2^?). Intensities for intramultiplet transitions were found to be: 219.4 keV, <0.004 (in units of 200 for annihilation radiation), 292.4 keV, <0.004, 365.0 keV, 0.03±0.03, 584.4 keV, <0.005, and 876.8 keV, <0.005.     

Vibrations of a taut string and torsional vibration of a gun barrel under the influence of a moving mass

Vibration of a string under a moving mass is considered. Owing to the interplay between inertial forces and the string tension this problem shows some differences from that of a travelling force. The torsional vibration of a gun barrel induced by the spin-up of a bullet, being of ballistic interest, is also treated.     

A potential diquark in the proton

A non-relativistic, QCD-based, potential quark model for the proton and the neutron inevitably predicts a spin-0 diquark structure with an rms radius of the order of 0.35 fm or smaller. We prove this by solving the (S wave}) hamiltonian by De Rüjula et al. with variational methods. It is essential to include all quark interactions and to use realistic test wave–functions. The protondelta mass difference, the magnetic moments and the nucleon charge radii can be reproduced only with wave functions that contain a mixture of quark–diquark and three–quark states. Approaches with just a quark–diquark component give incorrect magnetic moments, while those without diquarks lead to a too low proton–delta mass difference.     

Sub-nanosecond lifetimes in Te

The half-lives of the 1776.8 keV 6⁺ level and the 2497.3 keV 7^? level in ¹²⁶Te are measured by registering β-γ coincidences in the decay of ¹²⁶Sb. The results are $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext><mtext>(1776.8)\; =\; 66\pm 3</mtext><mtext>ps</mtext>}}$ and $\text{T}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext><mtext>(2497.3)\; =\; 152\pm 5\; </mtext><mtext>ps</mtext>}}$. The collective strength of the 6⁺ → 4⁺ transition depopulating the 1776.8 keV state is estimated. An additional half-life of 0.36±0.06 ns is found but not definitely assigned in the level scheme.