KMS, etc

A general form of the ``Wick rotation'', starting from imaginary-time Green functions of quantum-mechanical systems in thermal equilibrium at positive temperature, is established. Extending work of H. Araki, the role of the KMS condition and of an associated anti-unitary symmetry operation, the ``modular conjugation'', in constructing analytic continuations of Green functions from real- to imaginary times, and back, is clarified. The relationship between the KMS condition for the vacuum with respect to Lorentz boosts, on one hand, and the spin-statistics connection and the PCT theorem, on the other hand, in local, relativistic quantum field theory is recalled. General results on the reconstruction of local quantum theories in various non-trivial gravitational backgrounds from ``Euclidian amplitudes'' are presented. In particular, a general form of the KMS condition is proposed and applied, e.g., to the Unruh- and the Hawking effects. This paper is dedicated to Huzihiro Araki on the occasion of his seventieth birthday, with admiration, affection and best wishes.Comment: 56 pages, submitted to J. Math. Phy

Three-dimensional model study of the Arctic ozone loss in 2002/2003 and comparison with 1999/2000 and 2003/2004

We have used the SLIMCAT 3-D off-line chemical transport model (CTM) to quantify the Arctic chemical ozone loss in the year 2002/2003 and compare it with similar calculations for the winters 1999/2000 and 2003/2004. Recent changes to the CTM have improved the model's ability to reproduce polar chemical and dynamical processes. The updated CTM uses σ-θ as a vertical coordinate which allows it to extend down to the surface. The CTM has a detailed stratospheric chemistry scheme and now includes a simple NAT-based denitrification scheme in the stratosphere. In the model runs presented here the model was forced by ECMWF ERA40 and operational analyses. The model used 24 levels extending from the surface to ~55km and a horizontal resolution of either 7.5° x 7.5° or 2.8° x 2.8°. Two different radiation schemes, MIDRAD and the CCM scheme, were used to diagnose the vertical motion in the stratosphere. Based on tracer observations from balloons and aircraft, the more sophisticated CCM scheme gives a better representation of the vertical transport in this model which includes the troposphere. The higher resolution model generally produces larger chemical O3 depletion, which agrees better with observations. The CTM results show that very early chemical ozone loss occurred in December 2002 due to extremely low temperatures and early chlorine activation in the lower stratosphere. Thus, chemical loss in this winter started earlier than in the other two winters studied here. In 2002/2003 the local polar ozone loss in the lower stratosphere was ~40% before the stratospheric final warming. Larger ozone loss occurred in the cold year 1999/2000 which had a persistently cold and stable vortex during most of the winter. For this winter the current model, at a resolution of 2.8° x 2.8°, can reproduce the observed loss of over 70% locally. In the warm and more disturbed winter 2003/2004 the chemical O3 loss was generally much smaller, except above 620K where large losses occurred due to a period of very low minimum temperatures at these altitudes

First records of extinct kentriodontid and squalodelphinid dolphins from the Upper Marine Molasse (Burdigalian age) of Switzerland and a reappraisal of the Swiss cetacean fauna

The Swiss Upper Marine Molasse (OMM) documents a transgression event dated to around 21 to 17 million years in which dolphin and other vertebrate remains have been reported. We revised the whole cetacean (whales and dolphins) OMM assemblage available in main collections, focusing on the identification and interpretation of periotics (bone that contains the inner ear). Periotics are rare, but they provide the richest taxonomic information in the sample and hint to environmental associations. Micro-computerized tomography allowed the reconstruction of bony labyrinths for comparisons and environmental interpretations. Three families are represented by periotics: Kentriodontidae, Squalodelphinidae and Physeteridae. The cetacean taxonomic composition of the Swiss OMM reinforces biogeographical patterns reported for the Mediterranean and Paratethys during the Burdigalian at a regional scale and the Calvert cetacean fauna of the northwest Atlantic at oceanic scale

Aufnahme radioaktiver Stoffe durch Erdbeer· und Rebenblätter

Radioactive strontium in the form of an aqueous solution of 85 5rCl 2 was taken up by the leaves of strawberry plants and grapevines at different rates. Only a limited amount was transported from · the contaminated leaves into other plant organs. However, no strontium was found in the fruit. In contrast, radioactive caesium applied as an aqueous solution of 134CsCI was taken up very quickly from the leaf surface, transported from there to other plant parts and released to some extent into the soil via the roots. In our investigations, strawberry fruit showed a high caesium content. The caesium content in grape berries rose during growth and decreased again in a late phase of maturation and the nuclide was partly redistributed to other plant parts. Caesium reaching the soil may interact with day particles resulting in a very limited availability for plants. First results of investigations with grapevines in hydroculture demonstrated a close relationship between potassium supply and caesium release. The foliar up· take of radioactive strontium into plants is minor and represents therefore a negligible risk for the consumer of fruits. Radio· active caesium nuclides may however reach the human food chain through the leaves of food plants

Uptake and Transport of Radioactive Cesium and Strontium into Strawberry Plants and Grapevines After Leaf Contamination

Radioactive strontium in the form of a carrier-free aqueous solution of 85SrCl2 was taken up by the leaves of strawberry plants and grapevines at different rates. Only a limited amount was transported from the contaminated leaves into other plant organs. However, no strontium was found in the fruit. These findings show that bivalent strontium is mobile in plants only to a very minor extent. In contrast, radioactive cesium applied as an aqueous solution of carrier-free 134CsCl was taken up very quickly from the leaf surface, transported from there to other plant parts and released to some extent into the soil via the roots. In our investigations, strawberry fruit showed a high cesium content. The cesium content in grape berries rose during growth and decreased again in a late phase of maturation and the nuclide was partly redistributed to other plant parts. Cesium reaching the soil may interact with clay particles resulting in a very limited availability for plants. First results of investigations with · grapevines in hydroculture demonstrated a close relationship between potassium supply and cesium release. The foliar uptake of radioactive strontium into plants is minor and represents therefore a negligible risk for the consumer of fruits, berries and nuts. Radioactive cesium nuclides may however reach the hum.an food chain through the leaves of food plants

Development and Airborne Operation of a Compact Water Isotope Ratio Infrared Spectrometer

A sensitive laser spectrometer, named IRIS (water isotope ratio infrared spectrometer), was developed for the in situ detection of the isotopic composition of water vapour in the upper troposphere and the lower stratosphere. Isotope ratio measurements can be used to quantify troposphere stratosphere exchange, and to study the water chemistry in the stratosphere. IRIS is based on the technique of optical feedback cavity-enhanced absorption spectroscopy. It uses a room temperature near-infrared laser, and does not require cryogenic cooling of laser or detectors. The instrument weighs 51 kg including its support structure. Airborne operation was demonstrated during three flights aboard the European M55-Geophysica stratospheric research aircraft, as part of the AMMA/SCOUT-03 (African Monsoon Multidisciplinary Analysis/Stratospheric Climate links with emphasis on the Upper Troposphere and lower stratosphere) campaign in Burkina Faso in August 2006. The data are discussed with reference to a Rayleigh distillation model. As expected, there is no indication of non-mass-dependent fractionation (also known as mass-independent fractionation) in the troposphere. Furthermore, improvements to the thermal management system and a move to a (cryogen-free) longer-wavelength laser source are discussed, which together should result in approximately two orders of magnitude improvement of the sensitivit

Flight electronics of GC-mass spectrometer for investigation of volatiles in the lunar regolith

We introduce electronics designed to control measurement cycles performed with the compact neutral gas mass spectrometer (NGMS), which is a time-of-flight (TOF) system. NGMS is combined with a gas chromatograph (GC) and a pyrolysis oven to form a gas analytic complex on board the Russian Luna-Resurs spacecraft to land on the Moon. The instrument will investigate chemical composition of the soils at lunar polar regions and the tenuous lunar exosphere. NGMS measures the elemental, isotopic and molecular composition of gaseous samples including CHON compounds, water and noble gases, by recording TOF spectra that are converted to mass spectra during data analysis. Our miniature mass spectrometer has a robust and modular design. It combines an ion storage source with redundant thermionic electron emitters, a pulsed ion extraction for ion acceleration, ion drift path, ion mirror, a second ion drift path, and a high-speed microchannel plate detector. Starting from the ion source where species are ionized and the consecutive mass separation in the field free regions of a TOF section, ion packages arrive some microseconds later at the multichannel ion detector. The detector produces current pulses with peak widths of nanoseconds allowing for measurements with a high mass resolution in spite of a short drift tube length. During test measurements, we achieved mass resolution > 1000 together with a dynamic range of up to 10within 1 second integration time. Hence, the instrument depends on high electric field strengths in the ion-optical system and a high-speed and low-noise data acquisition system resulting in highly customized control electronics. We developed the complete electronic system complying with the mission requirements (power consumption of 25 watt maximum, size, mass and radiation tolerance) for controlling the instrument operation and acquiring data from this complex analytical package. Given the heritage from LASMA/Phobos-Grunt, CaSSIS/Exo-Mars, RTOF/Rosetta and P-BACE/MEAP missions, the presented design demonstrates that NGMS is capable to investigate chemical composition with allocated resources of power and size. Our flight-proven control unit operating NGMS represents a reliable system for further similar applications as the Neutral Gas and Ion Mass spectrometer NIM/PEP on board ESA's JUICE mission