bluuebunny/crossref_metadata_2025 huggingface dataset:
The Fragmentation of Asteroids – A Synopsis of Analytical Methods (Mitteilungen der Universitäts‐Sternwarte Jena Nr. 119)
Authors: Dorschner J.
Published: July 2007

Basing on the author's work a review of the possibilities as well as the limits of treating the problem of the collisional history of the asteroids by analytical methods is given. Using empirical data on rock fragmentation and general principles like symmetry and mass conservation the distribution function of the fragments arising from a single collision is analytically formulated. The size distribution of asteroids adjusting when crushing collisions have taken place a sufficiently long time can be obtained as the solution of an integrodifferential equation with partial derivatives (equation of fragmentation). Quasi‐stationary solutions of the equation of fragmentation are discussed for particular cases. The problem of the steady state is reduced to the solution of a transcendental equation. The results obtained show that analytical methods already offer a good theoretical understanding of the observed size distribution of the asteroids. They should be, therefore, a useful basis of carrying out numerical calculations.
The Extinction Feature at λ 2200 Å and the Diffuse Interstellar Lines (Mitteilungen der Universitäts‐Sternwarte Jena Nr. 120)
Authors: Dorschner J.
Published: July 2007

Correlations of the diffuse interstellar lines λλ 5780, 5797, and 6284 Å with the λ 2200 Å feature as well as the interstellar extinction in the visual and in the UV have been found.
On the Reynolds stresses in mean‐field hydrodynamics II. Two‐dimensional turbulence and the problem of negative viscosity
Authors: Krause F. , Rüdiger G.
Published: July 2007

The methods proposed in a foregoing paper are used for the derivation of the eddy viscosity of a two‐dimensional homogeneous isotropic turbulence. In contrast to three‐dimensional isotropic turbulence is shown that for the two‐dimensional case the eddy viscosity (i) has no definite sign, (ii) tends to zero if the molecular viscosity tends to zero, (iii) is negative for special cases. However, the modes with large wave numbers decay in any case as is shown by investigating a dispersion relation.
Gravitational attenuation and the internal heating of planetary bodies
Authors: Crowley R. J. , Woodward J. F. , Yourgrau W.
Published: July 2007

The hypothesis of gravitational attenuation is discussed and several theoretical problems with possible solutions are noted. It is pointed out that, if energy were attenuated out of the gravitational field by matter, it would ultimately be thermalized. Geothermal data are then employed to establish an upper limit to the gravitational attenuation coefficient, some fifteen orders of magnitude smaller than the currently accepted value. The internal heating of other planetary bodies is investigated to see if a yet smaller upper limit is deducible therefrom – with negative results.
Lichtelektrische Untersuchung der drei Mangan‐Sterne HD 207 857, HD 220 933 und HD 225 289
Authors: Hildebrandt G. , Schöneich W.
Published: July 2007

Die lichtelektrischen Untersuchungen in den Jahren 1969 und 1970 der drei Mangan‐Sterne HD 207857, HD 220933 und HD 225289 im UBV‐System zeigen für alle drei Objekte einen periodischen Lichtwechsel mit einer Amplitude von etwa 0.01 mag. Die Lichtkurve für HD 207857 zeigt eine Doppelwelle bei einer Periode von 20.70 Tagen. Die Periode für HD 220933 ergab sich zu 6.97 Tagen und für HD 225289 zu 6.4332 Tagen.
Non,thermal Cosmic Gravitational Radiation and Redshift Fluctuations
Authors: Dautcourt G.
Published: July 2007

Intergalactic gravitational radiation fields with wavelengths in the range of 1 to 103 Megaparsecs have remarkable observational effects if the energy density of the fields becomes comparable to the equivalent “critical” cosmological matter density χo = 3H02. In this case the perturbation in the space‐time metric caused by the radiation field is high enough to change the frequency and to shift the path of light rays of extragalactic objects in a random manner by observable amounts.

The present paper discusses the wave spectrum as a function of cosmic time and gives a statistical treatment of the redshift fluctuations.
On the Influence of a Large‐scale Magnetic Field on Turbulent Motions in an Electrically Conducting Medium
Authors: Rädler K.‐H.
Published: July 2007

This paper deals with turbulent motions in a homogeneous incompressible electrically conducting medium in the presence of a magnetic field which is on average homogeneous and stationary. Using a model in which the turbulence is produced by a stochastic body force, and supposing a weak interaction between motion and magnetic field, a method is developed for calculating the pair correlation tensor of the velocity field from that occuring in a zero magnetic field. As an example, the pair‐correlation tensor for a homogeneous stationary turbulence, which is isotropic and mirror‐symmetric for zero magnetic field, is determined. With obvious assumptions on the correlation for zero field, two results are obtained. Firstly, the turbulent velocity is reduced by the magnetic field, the component parallel to the field, however, less than those perpendicular to it. Secondly, the correlation length parallel to the field turns out to be greater than the one perpendicular to it, indicating a tendency towards two‐dimensional motion. Finally, the possibility of special situations is briefly discussed in which the turbulent velocity is enhanced by the magnetic field, and the anisotropies of the velocity components and the correlation lengths are opposite to those above.
Die träge und die schwere Masse eines Himmelskörpers nach der trägheitsfreien Dynamik und die Selbstabsorption der Schwerkraft
Authors: Treder H.‐J.
Published: July 2007

In unserer “trägheitsfreien” Dynamik (TREDER 1972) sind die effektiven trä,en Massen \documentclass{article}\pagestyle{empty}\begin{document}$ m_\alpha ^*$\end{document} der Teilchen Kα homogene Funktionen des “äußeren” NEWTONschen Gravitationspotentials \documentclass{article}\pagestyle{empty}\begin{document}$ f\sum\limits_\beta {'\frac{{m\beta }}{{\gamma _{\alpha \beta } }}}. $\end{document} Wir zeigen, daß aus dieser “Trägheitsinduktion” resultiert, daß die Summe \documentclass{article}\pagestyle{empty}\begin{document}$ \sum\limits_A^N {m_A^* } $\end{document} der effektiven trägen Massen \documentclass{article}\pagestyle{empty}\begin{document}$ m_A^* $\end{document} der N Teilchen KA eines Sterns immer größer ist als seine Gesamtmasse M*

hierbei ist M* die dynamisch bestimmte träge Masse des Sterns. Als Folge hiervon sind die tatsächlichen Gravitations‐Beschleunigungen der Teilchen KA im Sterninnern immer kleiner als diejenigen, die sich NEWTONisch aus der gravischen Masse \documentclass{article}\pagestyle{empty}\begin{document}$ fM = f\sum {m_A } $\end{document} des Sterns berechnen würden. — Wir vergleichen diesen Effekt mit dem der “Selbstabsorption der Schwere”, wie er aus unserer Tetradenfeldtheorie der Gravitation (TREDER 1967/71) folgt.
The General Metrical Fundamental Form of the DE SITTER Universes
Authors: Treder H.‐J.
Published: July 2007

Das allgemeine Linienelement eines DE SITTER‐Kosmos mit

hängt von zwei Integrationskonstanten A und B ab. Mit EINSTEIN's kosmologischer Konstante \documentclass{article}\pagestyle{empty}\begin{document}$ \lambda > o $\end{document} ist

und \documentclass{article}\pagestyle{empty}\begin{document}$ \varepsilon {\rm = }\frac{{{\rm 4}\lambda }}{{\rm 3}}AB $\end{document} AB gemäß der FRIEDMANNschen Gleichung.
Die Fallbeschleunigung in der SCHWARZSCHILD‐Metrik
Authors: Treder H.‐J. , Fritze K.
Published: July 2007

Die Fallbeschleunigung für die SCHWARZSCHILD‐Metrik wird abgeleitet und ihre Abhängigkeit von der Radialkoordinate r betrachtet.
Die Wechselwirkung zwischen homogener Turbulenz und inhomogenem magnetischen Feld in der Umgebung neutraler Flächen
Authors: RÜDIGER G.
Published: July 2007

In Fortführung der Untersuchung über den Einfluß eines konstanten Magnetfeldes auf homogene Turbulenz (RÜDIGER 1974) wird im Vorliegenden die Wirkung eines schwachen, schwach räumlich veränderlichen, eine Nullfläche enthaltenden Magnetfeldes bestimmt. Es wird nunmehr nicht nur die Isotropie sondern auch die Homogenität des ursprünglich als homogen und isotrop eingeführten Turbulenzfeldes aufgehoben. Wegen der endlichen Korrelationslänge wird das Bewegungsverhalten auch innerhalb der neutralen Schicht beeinflußt. Die dort anzutreffende anisotrope Dämpfung der turbulenten Bewegung wird für eine spezielle Klasse von Spektralfunktionen zwei‐ und dreidimensionaler Turbulenz angegeben.

Fernet wird der Einfluß des nunmehr inhomogenen Turbulenzfeldes auf das die Inhomogenität hervorrufende mittlere Magnetfeld bestimmt. Man erhält eine zeitliche Veränderung des mittleren Magnetfeldes, die mit Hilfe des BOCHNERschen Theorems als zusätzlicher Zerfallsmechanismus charakterisierbar ist.
Structural Investigations in the Central Part of the Coma Cluster on the Base of Equidensity Diagrams. I.
Authors: Richter N. , HÖGNER W.
Published: July 2007

Auf der Grundlage einer photographischen Himmelsaufnahme im Farbsystem V, die mit der Schmidtkamera 134/200/400 cm des Karl‐Schwarzschild‐Observatoriums Tautenburg erhalten wurde, werden mit Hilfe photographischer Äquidensiten maximale Durchmesser von Galaxien im Zentrum des Coma‐Haufens abgeleitet. Ein weiteres System von Durchmesserwerten bezieht sich auf mittlere Schwärzungsgebiete der Objekte. Die Ergebnisse werden mit einer Statistik von ROOD und BAUM verglichen, deren Durchmesserbestimmungen durch visuelle Messungen auf Platten erhalten wurden, die mit dem 5‐Meter‐Spiegel der Hale Observatories gewonnen wurden. Beide Statistiken erreichen Galaxien bis 19m. Sie sind vollständig bis 17m.5. Es zeigt sich, daß die Tautenburger Durchmesser die von ROOD und BAUM im Mittel um das Dreifache übertreffen, in zahlreichen Fällen um das Fünffache. Es werden Durchmesser‐Helligkeits‐Diagramme abgeleitet, Elliptizitäten der Objekte bestimmt und Korrektionswerte zur photometrischen Entzerrung von stark geneigten Objekten abgeleitet. Zur Beschreibung der Haufenstruktur werden Durchmesserfunktionen anstelle von Helligkeitsfunktionen abgeleitet. Die Genauigkeit der mit der Äquidensitenmethode aus den Durchmesser‐Helligkeits‐Diagrammen dargestellten Einzelhelligkeiten übertrifft die analogen Werte von ROOD und BAUM um das Doppelte.
Astrophysikalische Diskussion des COMPTONeffektes im äußeren Magnetfeld
Authors: Herrmann J. , KÄMpfer B.
Published: July 2007

Der Einfluß eines äußeren, zeitlich konstanten und homogenen Magnetfeldes auf das COMPTONspektrum, das durch die Streuung einer Photonenverteilung an einer Verteilung ultrarelativistischer Elektronen entsteht, wird diskutiert.
On the mass discrepancy in double galaxies
Authors: Oleak H.
Published: July 2007

Comparing the M/L‐distribution function of single spiral and irregular galaxies with that of double galaxies (S,S and E,E) from the list of KARACHENTSEV (1974) it can be shown that the mass discrepancy can be ascribed to the skewedness of this frequency function and thus to the strong dependence of the mean value of M/L on the dispersion. An unavoidable enlargement of the dispersion by errors of measurement and wrong attachment of objects of the sample always raises the mean of M/L. This effect could be then mistaken for a mass discrepancy.
Counts of galaxies in the region of the “intergalactic dark cloud” near ι microscopii
Authors: Meinunger I.
Published: July 2007

The distribution of the total numbers of galaxies down to about 18TH magnitude on 84 squares is largely in agreement with the structure of the hypothetic intergalactic absorbing cloud near ι Microscopii found by C. HOFFMEISTER. The counts of galaxies were performed on the WHITEOAK prints covering that region.
Remarks on Khalatnikov Lifshitz Type Theorems
Authors: Von Borzeszkowski H.‒H. , Kasper U.
Published: July 2007

It is shown that the proof of the g = o theorem established by KHALATNIKOV and LIFSHITZ in general relativity has to be supplemented by additional considerations. The same investigations are made for TREDER'S tetrad theory of gravitation.
Lichtelektrische Untersuchungen des Ap‐Sterns HD 148112
Authors: Schöneich W. , Hildebrandt G.
Published: July 2007

Der Ap‐Stern HD 148112 wurde im Zeitraum von Juli 1971 bis Juli 1972 lichtelektrisch im BV‐System untersucht. Der Stern zeigt mit einer Periode von 2.951 Tagen eine Doppelwelle in der Lichtkurve. Die Amplituden betragen in beiden Farbbereichen etwa 0.04 mag.
BOLTZMANNS Kosmogonie und die hierarchische Struktur des Kosmos
Authors: Treder H.‐J.
Published: July 2007

Gemäß BOLTZMANNS Kosmogonie quasi‐isolierter Systeme ist die Manningfaltigkeit der möglichen (d. i. mit den kanonischen Bewegungsgleichungen und den als „Hemmungen”︁ wirkenden Nebenbedingungen verträglichen) Vorgeschichten ein Maß für die Wahrscheinlichkeit des gegenwärtigen Zustandes eines Systems Σ. Diese Fundamental‐Hypothese von BOLTZMANN ist die Aufklärung des sogenannten „Wiederkehreinwandes”︁ von POINCARÉ und ZERMELO. BOLTZMANNS Prinzip bestimmt aber auch die epistemologische und methodologische Bedeutung z. B. der geologischen und paläontologischen Facies als „Dokumente”︁ für die Erdgeschichte.

Die Geschichte keines kosmischen Systems ist vollständig aus seiner Eigengesetzlichkeit allein verständlich. Die Systeme entstanden allgemein im Verband eines großen Obsersystems, und ihre Entstehungsgeschichte (z. B. die Kosmogonie der Planeten) ist die Geschichte ihrer Herauslösung aus diesem Obsersystem.

Aus diese Weise gelangen wir schließlich zu einer kosmogonischen Hierarchie kosmischer Systeme, und diese zeitartig geordnete Hierarchie ist letztlich äquivalent der räumlichen Hierarchie kosmischer Strukturen, wie sie die „hierarchische Kosmologie”︁ seit KANT und LAMBERT postuliert hat.

Das Universum ist eine räumlich und zeitlich nach oben unbeschränkte Hierarchie kosmischer Systeme: Σ0 Σ Σ1 Σ Σ Σ Σ Σ Σ Σ. Daher ist auch die astronomische „Metagalaxis”︁ nur ein System in einer unendlichen Mannigfaltigkeit neben‐ und übergeordneter Strukturen. — In einem Anhang geben wir ein mathematisches Modell für einen solchen „hierarchischen Evolutions‐Kosmos”︁ an, welches aus den kosmologischen Prinzipien der hierarchischen und der relativistischen Kosmologie ableitbar ist.
On the Possibility of a Finite Model Describing the Universe
Authors: Järnefelt G.
Published: July 2007

In his book “The expanding universe” EDDINGTON (1933) suggested the idea of an astronomical world model containing a finite number of material particles. Starting from this idea the author has speculated about the possibility to create a cosmological model where in addition also the number of geometrical points and time‐instants is finite (JÄRNEFELT 1929, 1949, 1951, 1954a, 1954b, 1957, 1964, 1974, JÄRNEFELT and KUSTAANHEIMO 1952, JÄRNEFELT and QVIST 1955). The ultimate goal would be a world model based essentially upon GALOIS fields. In order to explore such a possibility the most simple actually existing physical system, the structure describing a non‐relativistic free particle in an one‐dimensional Euclidean space, is treated here. A discrete representation of this system is outlined and then a GALOIS‐finitization of this platform is discussed. The author suggests that the method presented here for a very special case, could be generalizable and finally extended to a cosmological model.
Nova Cygni 1975. I. Beobachtungsmaterial und Entfernungsbestimmung
Authors: Bartl E. , Marx S. , Ziener R.
Published: July 2007

From the strength of the interstellar H‐ and K‐line in the spectrum of Nova Cygni 1975 its distance is determined to 1.2 kpc.
Variability of emission line spectrum and physical conditions in the nucleus of the seyfert galaxy NGC 1275
Authors: Pronik I.
Published: July 2007

The observational evidences on the variability of relative intensities of emission lines of the Seyfert galaxy NGC 1275 are discussed. The time scale of these variations is about half a year. It equals to the time scale of continuous and radio variations of the nucleus of that galaxy. The changes of the electron temperature Te and the electron density ne calculated from the emission line intensities were found to have a functional connection. This evidences that the physical conditions in the gaseous zone of the nucleus of NGC 1275 are recurrent.
Active nuclei of galaxies
Authors: Dibay E. A.
Published: July 2007

The parameters of fifteen active nuclei are determined from spectroscopic and photometric observations. The values of bolometric luminosity, gas volume and mass, kinetic energy, characteristic dimension and kinematic time‐scale are given. The fluxes of radiative and mechanical energy of the gas envelope are compared. A steady‐state model of the nucleus is proposed with the kinetic energy of the envelope being balanced by the light pressure. The life‐time of the nucleus appears to be of the same order of magnitude as the life‐time of the surrounding galaxy.

The broad emission lines suggest to be caused by the gravitational potential of the nucleus. The masses of the central bodies are calculated on this basis. The typical central body mass of an active nucleus is about 108 solar masses. The mass‐luminosity relation is constructed.

The steady‐state model seems to explain the optical variability process. Collaps to the center of separate gas clouds, as results of Rayleigh‐Taylor instability, leads to the flares, amplitudes and time‐scales being in agreement with observations.
Cosmogony of galaxies as based on the spatial distribution of matter
Authors: Rudnicki K.
Published: July 2007

A morphological box for the space distribution of galaxies and dark matter as the consequence of various types of cosmogonical hypotheses is presented. A short review of concepts of clustering of galaxies is given. One has to distinguish between the phenomena of “clusters of galaxies” and of “clustering of galaxies”. The second notion is more general. The investigations of KIANG, FLIN, and PEEBLES speak in favour of general clustering rather than overal existence of individual clusters. Individuals such as our Supergalaxy, Coma cluster etc. seem rather to be exceptional features.
Polteilchen in der TREDERSchen Tetradentheorie
Authors: Fuchs H.
Published: July 2007

In the framework of TREDERS' tetrad theory of gravitation the interaction of pole‐particles is considered in post‐NEWTONian approximation. The perihelion shift for the two‐body problem is calculated for different matter‐field‐couplings. In general it depends not only from the sum of the masses but also from the reduced mass. The additional term is connected with the absorption of gravitation.
Unusual extinction profiles by RAYLEIGHscattering
Authors: Shah G. A.
Published: July 2007

The extinction efficiencies for small smooth metallic particles (granules) have been calculated using rigorous MIEtheory of scattering. Strong size dependent resonances for spheres composed of sodium, potassium, and calcium have been found. The results seem to have relevance to the problems of interstellar grains especially with reference to structures in the observed extinction curve, diffuse bands and anomaly of cosmic abundances of elements.
Etude de la fonction dnx/dτn = ax + β dx/dτ
Authors: Fichera E.
Published: July 2007

General expressions of α and β developments, allowing to generalize GIBBS' formulae in the determination of orbits by means of observations, are given.
Zur Darstellung der anomalen EINSTEIN‐Effekte mit Hilfe einer effektiven Metrik
Authors: Treder H.‐J. , Gottlöber S.
Published: July 2007

Wir diskutieren die behaupteten Exzesse der gravo‐optischen EINSTEIN‐Effekte an der Sonne. Hierbei unterstellen wir hypothetisch die Signifikanz der in der Literatur behaupteten Anomalien und versuchen, diese mit Hilfe einer effektiven Raum‐Zeit‐Metrik darzustellen, die das formale Modell von dielektrischen Eigenschaften des Vakuums ist. Die effektive Metrik kann so gewählt werden, daß die durch sie bestimmten nichtlinearen elektromagnetischen Effekte mit der Quantenelektrodynamik kompatibel werden.
Small‐Scale Angular Fluctuations of Cosmic Background Radiation. Basic relations
Authors: Dautcourt G.
Published: July 2007

A statistical treatment is given of small‐scale angular fluctuations of cosmic background radiation propagating in FRIEDMANN models with Λ= o. It is assumed that the fluctuations arise from

the discrete nature of radiation sources;

density inhomogeneities in continuously distributed radiating matter or from

variable absorption along different light paths towards the observer.

The observable angular correlation function of the intensity fluctuations is expressed in terms of statistical measures of the sources of fluctuations. The rather general formulae are reduced as far as possible without specifying the frequency region.
Réflexions sur la contingence des lois de la Nature
Authors: Boneff N.
Published: July 2007

There are two fundamental conceptions concerning the laws of nature — these laws are eternal or they may vary in the course of time. We suggest an experiment in order to find an intermediary thesis — i.e. to discover that law, if it really exists, according to which a given law of nature varies, or, at least, to find out the direction in which this variation is performed.
An equatorially symmetric rotator model for magnetic stars
Authors: Oetken L.
Published: July 2007

Suggested by theoretical and empirical investigations, a very simple magnetic field distribution at the surface of magnetic stars is proposed. This model corresponds to the superposition of a dipole and a quadrupole, both lying in the equatorial plane with their axes in the same direction. The observed variations of the effective magnetic field strength of the sixteen stars investigated can be represented surprisingly well with this model. When the quadrupole contribution is large, the variation of the magnetic field vector over the surface of the star differs characteristically from that of the decentred dipole model; thus the difficulty with the latter, regarding the representation of both the effective magnetic field and the mean surface field with the same parameters may perhaps be avoided.
Discussion of infrared measurements of T Tauri stars and related objects
Authors: Rössiger S.
Published: July 2007

It is at first reported that certain kinds of stars which have been classified as T Tauri stars or related objects are in reality not of this type. After the exclusion of those objects, the infrared measurements accessible in the literature permit to draw some astrophysical inferences. It is then possible to distinguish three classes of light variations. All T Tauri stars have an infrared excess. From the colour indices H – K and K – L it can be deduced that the infrared excess for more than one half of the objects is due to the thermal radiation of the circumstellar dust envelope; for the remaining stars also free‐free radiation from the gas envelope can play an essential part. The largest infrared excesses EH–K were found with the hotter stars (spectral type A) and the strongest emission lines with the cooler stars (spectral types G, K, M). This can finally be explained by the fact that the convection zone in cooler stars reaches far down into their interior than in hotter stars.
Correlation analysis of the space and surface distribution of galaxies
Authors: Dautcourt G.
Published: July 2007

The paper presents a number of calculations which are useful for the interpretation of catalogues of galaxies. It is suggested that a correlation function approach based on a MAYER cluster expansion for the N‐point probability function of galaxies leads to a complete description of galaxy clustering. Other statistical measures of clustering such as the distribution function for the cell population or the distribution of the next neighbour distances are shown to be reducible to a correlation approach. For the classical cell count method smoothing effect estimates are given and the ZWICKY dispersion curve technique is studied. The relation between the space distribution and the surface distribution of galaxies is discussed in cosmological models of FRIEDMANN type. Deviations from PEEBLES' scaling law occur for catalogues extending to faint magnitudes and suggest the existence of strong evolutionary effects in the distribution of galaxies. From the DODD et al. field and the Jagiellonian field one derives — comparing the data with those of the ZWICKY catalogue — that the clustering amplitude decreases like (I + z)‐s within increasing redshift, where s is of the order 6. Since the catalogues extend to small redshifts only, it is not clear if this behaviour continues to larger redshifts. Within the observationally accessible range of z, the value of s does not essentially depend neither on the galaxian luminosity function nor on the deceleration parameter q0, it depends weakly on the assumed K correction.
A thin disc model of the galactic dynamo
Authors: Soward A. M.
Published: July 2007

An axisymmetric αω‐dynamo model of the Galactic disc is investigated. The disc is thin and its width, 2h*, varies slowly with distance, ωT*, from the axis of symmetry. The strength of the α*, varies linearly with axialdistance, z*, while differential rotation, dΩ*/dωT*, remains constant. Otherwise α* and dΩ*/dωT* are arbitrary functions of ωT*. The results are applied to the special case of the oblate spheroid first investigated by STIX (1976) and later by WHITE (1977). In the limit of small aspect ratio the new results agree with those obtained by WHITE and confirm that the dynamo numbers computed by STIX are too small.
A method for reddening determination in the uvby photometric system (Mitteilung der Universitätssternwarte zu Jena Nr. 133)
Authors: Reimann H. G.
Published: July 2007

A new method for reddening determination in the uvby system is described. Using a Quby parameter calibrated in terms of b–y it is possible to determine simultaneously luminosity, spectral type, reddening, and metallicity of a star. The colour excess rations for the uvby photometric system are given and also analytical functions for the ZAMS are presented.
The distribution of galaxies in the field of the hercules supercluster
Authors: Baier F. W. , Mai W.
Published: July 2007

The number‐density distribution of four ABELL‐clusters in the region of the Hercules supercluster was derived by counting galaxies on the red Palomar Sky Survey prints. For one isolated cluster the radial number‐density distribution and the radial cumulative galaxy distribution were calculated.
Evolution effects in the distribution of distant galaxies?
Authors: Dautcourt G. , Richter N.
Published: July 2007

The amplitudes of the two‐point correlation function for galaxies are compared for galaxy catalogues extending to different depths. Strong evolution effects in the pattern of galaxy distribution seem to be present suggesting a secular increase of the clustering amplitude. Other explanations would involve large errors in the identification of faint objects as galaxies or a considerable contamination of the counts by very young highly redshifted galaxies as recently proposed by TINSLEY.
Note on the population type of novae
Authors: Wenzel W. , Meinunger I.
Published: July 2007

By comparing the nova frequency in the halo of the Andromeda nebula with the density gradients of the “normal” halo stars of the Milky Way System we conclude that probably a high percentage, if not all, of the novae belong to population II.
On the tidal theory of solar activity
Authors: Hantzsche E.
Published: July 2007

The hypothesis of a generation or triggering of solar activity by the combined planetary tides on the solar surface is examined by a search for correlations between the sunspot numbers and the tidal amplitudes, using averaged values of several time scales (between one day and eleven years), and taking non‐linear amplitude effects into account. The result is negative: There exist no detectable correlations.
Laboratory spectra of phyllosilicates and the interstellar 10‐micrometer absorption band
Authors: Dorschner J. , Friedemann C. , Gürtler J.
Published: July 2007

The reliability of results obtained through infrared spectroscopy by means of the KBr pellet pressing technique is examined for silicates, using MIE calculations. The embedding medium causes a distortion of the profile of the 10‐μm band. The absorption coefficient may be enlarged by as much as 10 to 20 per cent. The absorption peak is shifted by 0.2 μm in the direction to larger wavelengths.

Mass absorption coefficients are derived from laboratory spectra for submicrometer‐sized particles of chamosite, chlorite, montmorillonite, serpentine, and talc. Chamosite and talc show the absorption peak at the wavelength position required by the observations. Concerning chlorite and montmorillonite the agreement seems to be tolerable. For each substance the band is, however, much too narrow in order to fit the observed profile.

On the basis of the measured absorption coefficients and assuming an ad hoc broadening mechanism curves of growth are calculated. With the values for chamosite column densities of 10‐4 to 2.5 · 10‐3 g cm‐2 for silicate dust are found in the line of sight toward infrared sources.
On the Real Number of Objects in the Tautenburg Catalogues of Blue Objects Suspected as Quasistellar (QSO)
Authors: Richter N.
Published: July 2007

The results of the U, B, V photometries of W. BRONKALLA and N. RICHTER near the north galactic pole are discussed. In these photometries which have been carried out on the same Tautenburg Schmidt plates the share of blue objects suspected as quasistellar (QSO) has been determined by total photometry of all starlike objects in selected partly overlapping test fields. The results of both photometries agree very well. The position of the blue objects of the Tautenburg catalogues and BRONKALLA's photometry in the two‐colour diagram is compared with the two‐colour diagram of QSO's published by C. BARBIERI and M. CAPPACIOLI. In both cases 65 per cent of the objects are placed on the right‐hand side and 35 per cent on the left‐hand side (region of white dwarfs) of the black‐body line. Therefore, it is no longer admissible to qualify in a photometric statistics of blue objects all those objects as white dwarfs which are situated on the left‐hand side of the black‐body line in the two‐colour plot. This result is confirmed by the discussion of the number‐magnitude relation of these objects. Clustering of blue objects and their connection with clusters of galaxies are discussed. Using results from A. SANDAGE and E. M. BURBIDGE and our own results one can conclude that more than 60 per cent of Tautenburg blue objects must be QSO's. For further spectroscopic and proper motion investigations it is proposed to prefer the objects placed on the left‐hand side of the black‐body line in order to obtain the real share of white dwarfs in this group of objects suspected to be quasistellar.
An equatorially symmetric rotator model for magnetic stars. II. Inhomogeneous element distribution
Authors: Oetken L.
Published: July 2007

For the construction of more realistic models of magnetic stars the influence of large inhomogeneities in the distribution of line absorbing elements over the stellar surface on the determination of the mean longitudinal magnetic field component, Beff, is discussed. In this paper we assume the same magnetic field geometry as in paper I, i.e. the superposition of a dipole and an axissymmetrical quadrupole both lying in the equatorial plane with their axes parallel to one another. The models for the inhomogeneties can be classified by the concentration of the line absorbing elements:

(1) at the polar caps, (2) in rings surrounding the polar caps, (3) in a belt in the neighbourhood of the “magnetic” latitude δ = 90°. The result of the computations shows that the amount of compensations of both polarities by integration over the visible hemisphere may be remarkably reduced, yielding values of Beff not so far away from the polar field strength as in the homogeneous models.

Moreover, the large quadrupole contribution necessary in some cases to represent the observations in the homogeneous models may be considerably smaller with inhomogeneites taken into account. First comparisons between computed and observed values of Beff(t) are made for the stars α2CVn, 53 Cam and HD 215441.
The spectra of three newly discovered high‐redshift quasars
Authors: Afanasjev V. L. , Karachentsev I. D. , Lipovetsky V. A. , Lorenz H. , Stoll D.
Published: July 2007

Spectra of three high‐redshift quasars discovered on low‐dispersion objective prism plates were obtained. We present the emission line identifications and redshifts of the objects. Equivalent widths, line widths and low‐resolution line profiles are given characterizing the quasar emission region.

The Lyα and CIV equivalent widths indicate that the considered quasars are luminous objects at high redshift. Both these equivalent widths are too low by a factor 4, whereas the N V/Lyα ratio is 5 times larger than predicted by the photoionisation models.

The line profiles are compared with logarithmic, electron‐scattering and Gaussian profiles. In all the spectra rich absorption line systems are evident.
Spectrographic observations of optical counterparts of 5C radio sources and of blue objects
Authors: Afanasjev V. L. , Karachentseva V. , Karachentsev I. D. , Notni P.
Published: July 2007

First results of spectrographic observations of bright optical 5C1 and 5C2 radio candidates and of some blue radio‐quiet objects are presented. Among them are three emission line galaxies, three possible quasars and four galactic stars.
Der Einfluß des SCHWARZSCHILD‐Effektes auf die Bahn‐und Systemelemente lichtschwacher und kurzperiodischer spektroskopischer Doppelsternsysteme
Authors: Yavuz I.
Published: July 2007

Es wird der Einfluß des SCHWARZSCHILD‐Effektes auf die Bahn‐ und Systemelemente lichtschwacher und kurzperiodischer spektroskopischer Doppelsterne untersucht. Dieser beeinflußt über die gemessenen Dopplerbreiten der Spektrallinien Beobachtungszeiten und Phasen. Um Form, Art und Größe der an die Beobachtungszeiten und Phasen anzubringenden Korrekturen und ihren Einfluß auf die Bahn‐ und Systemelemente zu bestimmen, werden zwei Beispielsysteme betrachtet. Es handelt sich hier um ein theoretisches und um ein wirkliches lichtschwaches und kurzperiodisches Doppelsternsystem, Bd + 57$ 1942. Die Bahn‐ und Systemelemente werden nach der Methode von WILSING und RUSSELL mit Hilfe einer IB M 370 bestimmt. Die daraus resultierenden Ergebnisse können wie folgt zusammengefaßt werden: 1. Die wegen des SCHWARZSCHILD‐Effektes an die Beobachtungszeiten t bzw. an die Phasen ϕ anzubringenden Korrekturen haben folgende Formen:

Hier sind t2 und t2 die Anfangs‐ und Endzeiten der Beobachtungen, P die Periode und p der SCHWARZSCHILD‐Exponent 2. Der Einfluß des SCHWARZSCHILD‐Effektes macht sich besonders bei den Elementen ω und T bemerkbar und verursacht eine Verschiebung der Lage des Periastrompunktes.

Dies ist ein bemerkenswertes Ergebnis, weil es einer Apsidendrehung des Systems entspricht. Deswegen müssen die Bahn‐ und Systemelemente der schwachen und kurzperiodischen spektroskopischen Doppelsternsystemen von den Einflüssen des SCHWARZSCHILD‐Effektes befreit werden.

3. Die wegen des SCHWARZSCHILD‐Effektes an die Beobachtungszeiten bzw. an die Phasen anzubringenden Korrekturen und ihre Einflüsse auf die Bahn‐ und Systemelemente sind bei den Elementen V,0, a sin i und e nicht groß und können deswegen in nicht größere Genauigkeit erfordernden Fällen vernachlässigt werden.
Generalized Gödel Universe with Heavy Photons
Authors: Dyllong U.
Published: July 2007

An exact solution of EINSTEIN's field equations with cosmological constant coupled with the field equations of a massive vector field is given. The model has zero expansion and shear, but nonvanishing constant rotation.
Positionen Kleiner Planeten und Kometen
Authors: Gressmann M.
Published: July 2007

Es werden topozentrische Positionen mehrerer Kleiner Planeten und Kometen für die Epoche 1950.0 mitgeteilt.
Beobachtungsergebnisse der Berliner Arbeitsgemeinschaft für Veränderliche Sterne e.V. (BAV) (BAV‐Mitteilungen Nr. 29)
Authors: Braune W. , Hübscher J. , Mundry E.
Published: July 2007

In dieser 12. Zusammenstellung von Beobachtungsergebnissen der BAV werden 231 beobachtete Minima von 58 Bedeckungssternen, 108 Maxima von 25 RR Lyrae‐Sternen, vier Maxima von vier δ Cephei‐Sternen, vier Maxima eines δ Scuti‐Sternes, 353 Ergebnisse von 77 Mira‐Sternen und 182 Ergebnisse von 23 langperiodischen, halbregelmäßigen, unregelmäßigen und RV Tauri‐Sternen der Jahre 1976 und 1977 mitgeteilt.
On Expanding MACH‐EINSTEIN Universes
Authors: Treder H.‐J.
Published: July 2007

The “telescopic” gravodynamics of the MACH‐EINSTEIN‐Doctrine gives expanding “MACHian clouds” as world models. The universe becomes a closed system (according to the classical statistical mechanics) if and only if the total energy H of this cloud, i.e. its HAMILTONian, vanishes. This cloud is the MACHian equivalent to the EINSTEIN‐de SITTER universe of general relativity (or of “NEWTONian cosmology”). However, the MACHian cloud with H = o describes a linearly expanding universe.
Comments on the HUBBLE Diagram, the Luminosity Function and the Space Density Evolution of Radio Quiet Quasars
Authors: Notni Peter
Published: July 2007

The consequences of a pure power law luminosity function on the distribution of objects in the HUBBLE diagram are described. As long as such a law acts, magnitudes do not contain any information on distances. A high value of the coefficient of the luminosity function of radio quiet quasars, b = 0.95 ± 0.05 in the expression lg ψ(M) ∽ b. M, is shown to be plausible. This implies a high density evolution, ǫ ∽ (1 + z)k, with k near 9–10. Findings from modern samples, searched on low‐dispersion spectral plates point to an even stronger evolution at z < 2.5; the discrepancy may be removed if Lα/Hβ > 3 (about 30) for these radio‐quiet QSOs.
Barred Spirals, Double Galaxies and massive Halos1
Authors: Bergh Sidney Van Den
Published: July 2007

It is shown that there is no significant dependence of the frequency with which barred spirals occur on environment. Therefore, the difference between normal and barred spirals must be largely due to initial conditions. The excess of early type galaxie (in particular ellipticals and SO's) among the statistically selected binary samples is probably caused by a contamination by cluster members and will therefore result in a systematic overestimate of the masses of binary galaxies. The large fraction of multiple first‐ranked galaxies found in rich clusters of BAUTZ‐MORGAN type I is surprising in view of tidal effects and dynamical friction, which should lead to the destruction of such massive binary systems on a time scale much shorter than the age of the Universe.
Optical Image of Stars in the Camera Field
Authors: Tschobanoff P. D. , Nikolov N. S.
Published: July 2007

The possibility the turbulent atmosphere to act as a cause for an amplification of the optical star images is considered. This is made on introducing the turbulent atmosphere a an optical collimator set. Some considerations about the modelling and formalization of this effect are made. Finally some consequences relative to the optical record photometrical information extraction are mentioned.
Line Formation in Turbulent Media with Finite Correlation Length
Authors: Stahlberg J.
Published: July 2007

The influence of a stochastic velocity field on the line formation is investigated. A method similar to the mean field electrodynamics is described, where only two‐point correlations are taken into account. The influence of velocity model parameters, e. g. the correlation length and the dispersion of the velocity field, on the line profiles is discussed by simplified assumptions.
On Measuring the Dynamical Age of Clusters of Galaxies (Mitteilungen der Universitätssternwarte zu Jena Nr. 139) Universitätssternwarte and Zentralinstitut für Astrophysik der Akademie der Wissenschaften der DDR With 4 Figures
Authors: Schmidt K.‐H. , Baier F. W.
Published: July 2007

Die von S. von HOERNER (1976) vorgeschlagene Methode zur Bestimmung des dynamischen Alters von n‐Körpersystemen wird auf Galaxienhaufen angewendet und der Entwicklungsparameter W ermittelt. Danach ist der Virgo‐Haufen einer der dynamisch jüngsten Galaxienhaufen.
On a discription of dynamical properties of the gravitational field in vacuum
Authors: Sedov L. I.
Published: July 2007

The PETROV representation of the vacuum field classification is discussed. The introduction of canonical tetrads leads to an energy definition based of the Ricci rotation coefficients.
Search and Photographic Photometry of Ultraviolet Excess Objects in the Region of the 5C1 Radio Survey
Authors: Notni P.
Published: July 2007

A sample of ultraviolet excess objects in a 12.56 square degree field near α = 9h40m, δ = +50° (5C1‐radio survey) is presented. In addition to starlike or and nearly starlike objects a sample of more diffuse ones is listed, presumably containing many Markarjan‐type galaxies. UBV‐photometry and first spectroscopic results are communicated; the number magnitude relation and the projected number‐density of the objects are shortly discussed.
Completeness and reliability of star counts from microphotometer scannings
Authors: Richter G. M.
Published: July 2007

If there plates of the same field are scanned and star catalogues are compiled from these scans then completeness and reliability of the catalogues and an estimate of the true star numbers can be derived as functions of the brightness or other parameters down to the plate limit. An applications is described.
Möglichkeiten der photometrischen Untersuchung von Kugelhaufen mittels photographischer Äquidensiten
Authors: Strugatskaya A. A. , Högner W. , Ziener R.
Published: July 2007

Es wird eine Methode beschrieben, mit der auf der Basis von Äquidensiten Oberflächenhelligkeiten von Kugelhaufen abgeleitet werden können.
Beobachtungen kleiner Planeten
Authors: Landgraf W.
Published: July 2007

Nachfoigend sind Positionen kleiner Planeten mitgeteilt, die aus photographischen Aufnahmen, angestellt an der Sternwarte der Gesamthochschule Siegen, erhalten wurden.
X‐ray emission – an ageing effect of galaxy clusters (Mitteilungen der Universitäts‐Sternwarte zu Jena Nr. 145)
Authors: Schmidt Karl‐Heinz
Published: July 2007

The observed X‐ray luminosity, LX, and temperature, TX, of clusters of galaxies are correlated with the dynamical evolution modulus, W, defined by VON HOERNER (1976). Obviously X‐ray emission is an ageing effect of galaxy clusters.
Astrophysical statistics of compact galaxies near the galactic north pole. Part II. Blue galaxies in the tautenburg catalogue of compact galaxies
Authors: Richter N.
Published: July 2007

From the Tautenburg catalogue of 745 compact galaxies in 4 fields round M3 blue objects are selected by help of the color index U – B ≧ −0.40 mag and by spectroscopic inspection on objective prism plates. There are found 45 objects as blue or suspected to have emissions.
Visual minima of eclipsing variables
Authors: Kreiner J. M. , Mistecka A. , Winiarski M.
Published: July 2007

This paper contains 57 heliocentric minima for 37 eclipsing variables.
User's guide to REDUCE subroutines for algebraic computations in general relativity
Authors: Dautcourt G. , Jann K.‐P. , Riemer E. , Riemer M.
Published: July 2007

Es werden Unterprogramme für allgemein‐relativistische algebraische Rechnungen in dem von Anthony Hearn entwickelten algebraischen Programmsystem REDUCE, das auf der Computersprache LISP basiert, beschrieben. Die erste Programmgruppe berechnet Konkominanten des metrischen Tensors wie den Riemann‐Tensor, den Ricci‐Skalar, den Einstein‐und Weyl‐Tensor aus seinen kovarianten oder kovarianten und kontravarianten Komponenten. Eine der Prozeduren schließt die Berechnung der Maxwell‐Gleichungen und Invarianten wie auch des Maxwellschen Energie‐Impuls‐Tensors ein. Eine zweite Gruppe benutzt die Komponenten einer Nulltetrade als Eingang und berechnet die Tetrad‐Komponenten des Riemann‐Tensors, des Einstein‐Tensors und – falls erwünscht – die 14 lokalen Invarianten des Riemann‐Tensors. Eine Bestimmung des Petrov‐Types ist ebenfalls enthalten.

Störungsrechnungen sind möglich und lassen sich effektiv durchführen. Die Form der Ausgabe ist flexibel. Weitere Programme sind auf Anforderungen verfügbar.

Der Artikel sollte es einem mit der Allgemeinen Relativitätstheorie vertrauten Leser ermöglichen, das Programmpaket auch ohne Kenntnis vom Computersprachen zu benutzen.
Selection, statistics and photometry of compact galaxies with different instrumental equipment. Part III. Selection and statistics with objective prism plates
Authors: Richter N.
Published: July 2007

The application of Tautenburg objective prism plates with a limiting identification magnitude of 19m.0 (B) for the selection of compact galaxies shows the superiority of this method over the hitherto used selection on the basis of the normal photographic sky plates with the same limiting magnitude.

Die Benutzung von Tautenburger Objektivprismenaufnahmen bis zu einer Identifzierungsreichweite von 19m.0 (B) für die Selektierung von kompakten Galaxien zeigt die Überlegenheit dieser Methode gegenüber den bisher durchgeführten Selektierungen auf konventionellen photographischen Himmelsaufnahmen gleicher Reichweite.
Photometrische Untersuchungen des Ap‐Sternes HD 153882
Authors: Hempelmann A.
Published: July 2007

Reihenmessungen des Ap‐Sterns HD 153882 erbrachten keinen Hinweis auf kurzzeitige Variabilität. Eine Untersuchung des gesamten zugänglichen Beobachtungsmaterials ergab mit hoher Wahrscheinlichkeit eine Veränderlichkeit des auch von anderen Autoren verwendeten Vergleichsstern HD 154228. Die Elemente dieses Lichtwechsels werden bestimmt und die Elemente des Lichtwechsels von HD 153882 did verbessert.
Automatisierung astronomischer Beobachtungs‐ und Auswertemeßtechnik mit Hilfe eines Kleinrechners im Dialogbetrieb (Mitteilung der Universitäts‐Sternwarte zu Jena Nr. 142)
Authors: Schielicke R. , Stecklum B. , Tenner B.
Published: July 2007

Zur wahlweisen online‐Steuerung von drei Meßeinrichtungen (photonenzählendes Sternphotometer, Registrierphotometer und Irisblendenphotometer) durch einen Kleinsteuerrechner wurde eine Interpreter‐Programmiersprache modifiziert. Damit ist es möglich, im Dialogbetrieb, aber auch durch Abarbeiten von Programmen die Meßabläufe zu steuern, die Meßwerte zu erfassen und auszuwerten und gegebenenfalls Parameter des Meßprozesses zu optimieren.
Eddingtons Zahlen, Einsteins Kriterium und Rydbergs rationelles Dimensionssystem
Authors: Treder H.‐J.
Published: July 2007

Eddingtons kosmologische Zahlen ω ≈ hc/fm2∼ 1040 verbinden – ganz im Sinne des Machschen Prinzips und der Mach‐Einstein‐Doktrin – „teleskopisch”︁ kosmologische und mikroskopische Größen. Eddingtons Zahlen geben auch den Größenordnungs‐Hiatus zwischen Gravitations‐ und anderen Wechselwirkungen an. Sie enthalten damit das Problem des physikalischen Sinnes der „großen Zahlen”︁. Nach den dimensionsanalytischen Postulaten von Einstein, Bridgman u. a. darf man solche großen Zahlen nicht einfach als Zahlenkoeffizienten der physikalischen Gleichungen hinnehmen. Die Dimensionsanalyse führt aber auch auf Rydbergs Problem der „physikalischen Dimensionen”︁ von Länger L, Fläche S und Volumen V, wobei in der Mikrophysik diese Größen „operationalistisch”︁ unabhängig werden. Diese neuen physikalischen Dimensionen verlangen neue universelle Konstanten, welche im Sinne der „Physikalisierung der Geometrie”︁ die physikalischen Zusammenhänge zwischen L2 und S bzw. L3 und V herstellen (Dällenbachs „Flächenkonstante des Vakuums”︁ bzw. die „universelle Volumen‐Konstante”︁). Auf Plancks Elementarkonstanten h, c und f als Einheiten bezogen, haben die Konstanten den Zahlenwert der Eddingtonschen Zahl. Newtons Gravitationsgesetz und Coulombs Gesetz haben dieselbe Form, aber die Gravitation ist Geometrie und hängt auch von S‐1 ∼ α‐1 L‐2 ∼ ω‐1 L‐2 ab.