Ruedi Graf, Die Tagebücher des Pfarrers Diethelm Schweizer (1751–1824), 2010

No abstract availabl

Probing the initial conditions of high-mass star formation -- IV. Gas dynamics and NH2_2D chemistry in high-mass precluster and protocluster clumps

The initial stage of star formation is a complex area study because of its high density and low temperature. Under such conditions, many molecules become depleted from the gas phase by freezing out onto dust grains. However, the deuterated species could remain gaseous and are thus ideal tracers. We investigate the gas dynamics and NH$_2$D chemistry in eight massive pre/protocluster clumps. We present NH$_2$D 1$_{11}$-1$_{01}$ (at 85.926 GHz), NH$_3$ (1, 1) and (2, 2) observations in the eight clumps using the PdBI and the VLA, respectively. We find that the distribution between deuterium fractionation and kinetic temperature shows a number density peak at around $T_{\rm kin}=16.1$ K, and the NH$_2$D cores are mainly located at a temperature range of 13.0 to 22.0 K. We detect seven instances of extremely high deuterium fractionation of $1.0 \leqslant D_{\rm frac} \leqslant 1.41$. We find that the NH$_2$D emission does not appear to coincide exactly with either dust continuum or NH$_3$ peak positions, but often surrounds the star-formation active regions. This suggests that the NH$_{2}$D has been destroyed by the central young stellar object (YSO) due to its heating. The detected NH$_2$D lines are very narrow with a median width of $\rm 0.98\pm0.02 km/s$. The extracted NH$_2$D cores are gravitationally bound ($\alpha_{\rm vir} < 1$), are likely prestellar or starless, and can potentially form intermediate-mass or high-mass stars. Using NH$_3$ (1, 1) as a dynamical tracer, we find very complicated dynamical movement, which can be explained by a combined process with outflow, rotation, convergent flow, collision, large velocity gradient, and rotating toroids. High deuterium fractionation strongly depends on the temperature condition. NH$_2$D is a poor evolutionary indicator of high-mass star formation in evolved stages, but a useful tracer in the starless and prestellar cores.Comment: 27 pages, 25 figures, 6 tables, accepted for publication in A&

Outflows, Accretion, and Clustered Protostellar Cores around a Forming O Star

We present a Submillimeter Array study in the 1.3 mm waveband of the NGC 7538 IRS 1--3 massive star-forming region. The brightest core in the mm continuum map, MM1, harbors the IRS 1 young O star. The core has a gas temperature of about 245 K and shows spatially unresolved emission in complex organic molecules, all typical of a hot molecular core. Toward MM1, redshifted absorption is seen in molecular lines with different energies above the ground state. This absorption probes inward motion of the dense gas toward the central young O star, and the estimated mass accretion rate reaches 10^{-3} Msun/yr. Multiple outflows are seen in the CO and 13CO maps. The gas mass of 50 Msun and mass outflow rate of 2.5 by 10^{-3} Msun/yr measured in CO line wings are dominated by the MM1 outflow, which is most likely driven by a fast wide-angle wind. Apart from MM1, we discover eight new dusty cores, MM2--9, within a projected distance of 0.35 pc from MM1. These cores show no counterpart in infrared or radio continuum emission, while seven of them appear to be forming intermediate- to high-mass stars. This manifests a deeply embedded star-forming component of the parent cloud of IRS 1--3. Apparently we are observing a Trapezium system in formation, and the system is presumably surrounded by a cluster of lower mass stars.Comment: Accepted for publication in Ap

High-mass star-forming cloud G0.38+0.04 in the Galactic center dust ridge contains H2CO and SiO masers

We have discovered a new H2CO (formaldehyde) 11,0−11,1 4.82966 GHz maser in Galactic center Cloud C, G0.38+0.04. At the time of acceptance, this is the eighth region to contain an H2CO maser detected in the Galaxy. Cloud C is one of only two sites of confirmed high-mass star formation along the Galactic center ridge, affirming that H2CO masers are exclusively associated with high-mass star formation. This discovery led us to search for other masers, among which we found new SiO vibrationally excited masers, making this the fourth star-forming region in the Galaxy to exhibit SiO maser emission. Cloud C is also a known source of CH3OH Class-II and OH maser emission. There are now two known regions that contain both SiO and H2CO masers in the CMZ, compared to two SiO and six H2CO in the Galactic disk, while there is a relative dearth of H2O and CH3OH Class-II masers in the CMZ. SiO and H2CO masers may be preferentially excited in the CMZ, perhaps because of higher gas-phase abundances from grain destruction and heating, or alternatively H2O and CH3OH maser formation may be suppressed in the CMZ. In any case, Cloud C is a new testing ground for understanding maser excitation conditions

"Ich habe alles reiflich erwogen" : Wirklichkeit und Ideal in Karl Kraus' "Die letzten Tage der Menschheit"

Seiner Gattung nach ist das Monumentaldrama von Karl Kraus "Die letzten Tage der Menschheit" unzweifelhaft eine Satire. Einen Zugang zum Verständnis kann denn auch Schillers berühmte Satirebestimmung eröffnen. Sie steht in seiner Abhandlung "Über naive und sentimentalische Dichtung", die erstmals 1795/96 in den "Horen" erschien. Darin lautet die Definition der Satire als einer sentimentalischen Gattung folgendermaßen: "In der Satire wird die Wirklichkeit als Mangel dem Ideal als der höchsten Realität gegenübergestellt. Es ist übrigens gar nicht nötig, daß das letztere ausgesprochen werde, wenn der Dichter es nur im Gemüt zu erwecken weiß; dies muß er aber schlechterdings, oder er wird gar nicht poetisch wirken. Die Wirklichkeit ist also hier ein notwendiges Objekt der Abneigung, aber, worauf hier alles ankömmt, diese Abneigung selbst muß wieder notwendig aus dem entgegengesetzten Ideale entspringen. […] Die pathetische Satire muß also jederzeit aus einem Gemüte fließen, welches von dem Ideal lebhaft durchdrungen ist. Nur ein herrschender Trieb nach Übereinstimmung kann und darf jenes tiefe Gefühl moralischer Widersprüche und jenen glühenden Unwillen gegen moralische Verkehrtheit erzeugen, welche in einem Juvenal, Swift, Rousseau, Haller und andern zur Begeisterung wird"

Für die Uebungen der Centralschule 1857

[gezeichnet von] Karl PestalozziOstorientier

[Planungsvariante des Gebiets an der Oberen Bahnhofstrasse Zürich] : [Situationsplan]

Pestalozzi und Breitinge

Ueber die Rheincorrection im Canton St. Gallen

von Karl PestalozziSeparatabdruck aus der Vierteljahrsschrift der Naturforschenden Gesellschaft in Züric