First Penning-trap mass measurement in the millisecond half-life range: the exotic halo nucleus 11Li

In this letter, we report a new mass for $^{11}$Li using the trapping experiment TITAN at TRIUMF's ISAC facility. This is by far the shortest-lived nuclide, $t_{1/2} = 8.8 \rm{ms}$, for which a mass measurement has ever been performed with a Penning trap. Combined with our mass measurements of $^{8,9}$Li we derive a new two-neutron separation energy of 369.15(65) keV: a factor of seven more precise than the best previous value. This new value is a critical ingredient for the determination of the halo charge radius from isotope-shift measurements. We also report results from state-of-the-art atomic-physics calculations using the new mass and extract a new charge radius for $^{11}$Li. This result is a remarkable confluence of nuclear and atomic physics.Comment: Formatted for submission to PR

Non-classical symmetries and the singular manifold method: A further two examples

This paper discusses two equations with the conditional Painleve property. The usefulness of the singular manifold method as a tool for determining the non-classical symmetries that reduce the equations to ordinary differential equations with the Painleve property is confirmed once moreComment: 9 pages (latex), to appear in Journal of Physics

Group analysis and exact solutions of a class of variable coefficient nonlinear telegraph equations

A complete group classification of a class of variable coefficient (1+1)-dimensional telegraph equations $f(x)u_{tt}=(H(u)u_x)_x+K(u)u_x$, is given, by using a compatibility method and additional equivalence transformations. A number of new interesting nonlinear invariant models which have non-trivial invariance algebras are obtained. Furthermore, the possible additional equivalence transformations between equations from the class under consideration are investigated. Exact solutions of special forms of these equations are also constructed via classical Lie method and generalized conditional transformations. Local conservation laws with characteristics of order 0 of the class under consideration are classified with respect to the group of equivalence transformations.Comment: 23 page

Smooth Gowdy symmetric generalized Taub-NUT solutions

We study a class of S3 Gowdy vacuum models with a regular past Cauchy horizon which we call smooth Gowdy symmetric generalized Taub-NUT solutions. In particular, we prove existence of such solutions by formulating a singular initial value problem with asymptotic data on the past Cauchy horizon. The result of our investigations is that a future Cauchy horizon exists for generic asymptotic data. Moreover, we derive an explicit expression for the metric on the future Cauchy horizon in terms of the asymptotic data on the past horizon. This complements earlier results about S2xS1 Gowdy models.Comment: 56 pages, 1 figure. The new version contains a detailed explanation of the Fuchsian method on the 2-spher

New results on group classification of nonlinear diffusion-convection equations

Using a new method and additional (conditional and partial) equivalence transformations, we performed group classification in a class of variable coefficient $(1+1)$-dimensional nonlinear diffusion-convection equations of the general form $f(x)u_t=(D(u)u_x)_x+K(u)u_x.$ We obtain new interesting cases of such equations with the density $f$ localized in space, which have large invariance algebra. Exact solutions of these equations are constructed. We also consider the problem of investigation of the possible local trasformations for an arbitrary pair of equations from the class under consideration, i.e. of describing all the possible partial equivalence transformations in this class.Comment: LaTeX2e, 19 page

First Astronomical Use of Multiplexed Transition Edge Bolometers

We present performance results based on the first astronomical use of multiplexed superconducting bolometers. The Fabry-Perot Interferometer Bolometer Research Experiment (FIBRE) is a broadband submillimeter spectrometer that achieved first light in June 2001 at the Caltech Submillimeter Observatory (CSO). FIBRE'S detectors are superconducting transition edge sensor (TES) bolometers read out by a SQUID multiplexer. The Fabry-Perot uses a low resolution grating to order sort the incoming light. A linear bolometer array consisting of 16 elements detects this dispersed light, capturing 5 orders simultaneously from one position on the sky. With tuning of the Fabry-Perot over one free spectral range, a spectrum covering Δλ/λ= 1/7 at a resolution of δλ/λ ≈ 1/1200 can be acquired. This spectral resolution is sufficient to resolve Doppler-broadened line emission from external galaxies. FIBRE operates in the 350 µm and 450 µm bands. These bands cover line emission from the important star formation tracers neutral carbon [Cl] and carbon monoxide (CO). We have verified that the multiplexed bolometers are photon noise limited even with the low power present in moderate resolution spectrometry

Book Reviews

Basic Neurology. Ed. by J. Gilroy and P. L. Holliday. Pp. vii + 373. Illustrated. R27,90. London: Macmillan. 1982.The Pathology of the Heart. By E. G. J. Olsen. Pp. ix + 402. Illustrated. R91,85. London: Macmillan. 1982.Profile of Disease and Health Care in South Africa. By H. C. J. van Rensburg and A. Mans. Pp. xvii + 319. R29,50. Pretoria: Academica Press. 1982.Principles of Ambulatory Medicine. Ed. by L. R. Barker, J. R. Burton and P. D. Zieve. Pp. xiii + 1127. Illustrated. R78,-. Baltimore, Maryland: Williams & Wilkins. 1982.Topical Reviews in Accident Surgery, vol. 2. Ed. by N. Tubbs and P. S. London. Pp. ix +258. Illustrated. £18,50. London: Wright PSG.1982.Early Care of the Injured Patient. 3rd ed. Ed. by A. J. Wait, L. F. Peltier, B. A. Pruitt jun, D. D. Trunkey and R. F. Wilson. Pp. xv + 413. Illustrated. Philadelphia: W. B. Saunders. 1982.Current Pediatric Therapy. 10th ed. By S. S. Gellis and B. M. Kagan. Pp. xxxviii + 776. R94,25. Philadelphia: W. B. Saunders. 1982.Selected Techniques in Interventional Radiology,vol. 19 (Saunders Monographs in Clinical Radiology). By S. Kadir, S. L. Kaufman, K. H. Barth and R. 1. White jun. Pp. xi +216. Illustrated. R76,75. Philadelphia: W. B. Saunders. 1982.Clinical Topics in Internal Medicine. Ed. by G. M. Tisi and H. M. Ranney. Pp. xii 173. Illustrated. Baltimore, Maryland: Williams & Wilkins. 1982.Recognizable Patterns of Human Malformation: Genetic Embryologic and Clinical Aspects (Major Problems in Clinical Pediatrics, vo!. vii). 3rd ed. By W. David and M. D. Smith. Pp. xvii + 653. Illustrated. R78,55. Philadelphia: W. B. Saunders. 1982.The Patient and the Plastic Surgeon. By R. M. Goldwyn. Pp. xiii + 255. Boston: Little, Brown. 1981.The Aging Lumbar Spine. By S. W. Wiesel, P. Bernini and R. H. Rothman. Pp. 257. Illustrated. R69,55. Philadelphia: W. B. Saunders. 1982.Postoperative Complications of Intracranial Neurological Surgery. By N. H. Horwitz and H. V. Rizzoli. Pp. xi + 472. Illustrated. Baltimore: Williams & Wilkins. 1982.Current Topics in Inflammation and Infection (International Academy of Pathology Monograph). Ed. by G. Majno, R. S. Cotran and . Kaufman. Pp. xi + 242. Illustrated. Baltimore, Maryland: Williams & Wilkins. 1982.Radiology of the Ear, Nose and Throat. By G. E. Valvassori, G. D. Porter, W. N. Hanafee, B. L. Carter and R. A. Buckingham. Pp. viii + 342. Illustrated. RI94,30. Philadelphia: \Y/. B. Saunders. 1982.Neuropathology ofParasitic Infections. By W. J. Brown and M. Voge. Pp. 240. Illustrated. RI5,-. Oxford: Oxford Medical Publishers. 1982.Herzkrankheiten: Pathophysiologie, Diagoostik, Therapie. 2nd ed. By H. Roskamm and H. Reindel!. Pp. xxxiii + 1543. Illustrated. DM 278,-. Berlin: Springer-Verlag. 1982.Review ofSpeech, Language and Hearing, vols I, 2and 3. By N. J. Lass, L. V. McReynolds, J. L. Northern and D. E. Yoder. Illustrated. R36,20 each. Philadelphia: W. B. Saunders. 1982

Spin transport theory in ferromagnet/semiconductor systems with non-collinear magnetization configurations

We present a comprehensive theory of spin transport in a non-degenerate semiconductor that is in contact with multiple ferromagnetic terminals. The spin dynamics in the semiconductor is studied during a perturbation of a general, non-collinear magnetization configuration and a method is shown to identify the various configurations from current signals. The conventional Landauer-B\"{u}ttiker description for spin transport across Schottky contacts is generalized by the use of a non-linearized I-V relation, and it is extended by taking into account non-coherent transport mechanisms. The theory is used to analyze a three terminal lateral structure where a significant difference in the spin accumulation profile is found when comparing the results of this model with the conventional model.Comment: 17 pages, 10 figure