bluuebunny/crossref_metadata_2025 huggingface dataset:
Über die Bestimmung absoluter Koordinatensysteme mit Hilfe von Planetenbeobachtungen
Authors: Schmeidler F.
Published: July 2007

Die Bedingungsgleichungen für die Verbesserung der Bahnelemente von Planeten aus Meridianbeobachtungen werden so umgeformt, daß in den Koeffizienten nur die geozentrischen Koordinaten des Planeten und der Sonne auftreten. Für Planeten, die sich in Bahnen kleiner Exzentrizität und Neigung bewegen, können die Gleichungen in der bequemen Form

geschrieben werden; dabei hängen die Koeffizienten ai, bi auch von der Größe α—α⊙ ab, die ein Maß für die seit der letzten Zeit Oppositon vergangene Zeit ist. Das Beobachtungsmaterial ist in Gruppen zu unterteilen derart, daß in jeder Gruppe der Wert von α—α⊙ und damit auch die Werte der ai, bi konstant sind. In der Regel interessieren nur die Systemkorrektionen E und D, die für Instrumente und Beobachter charakteristisch sind; die Bestimmung der Bahnelemente der Planeten kann meist späteren Bearbeitungen überlassen werden.

Die vereinfachte Form der Gleichungen ermöglicht eine übersichtliche Diskussion, welche der Unbekannten unter welchen Bedingungen sicher getrennt werden können. Ein numerisches Beispiel zeigt, daß die Voraussetzung kleiner Exzentrizität und Neigung auch für Mars noch zulässig ist, bei dem wegen Bahnform und Erdnähe maximale Fehler zu erwarten sind. Die mit den Münchner Meridianinstrumenten in den Jahren 1941—1956 gemachten Beobachtungen großer Planeten werden mit Hilfe des erläuterten Verfahrens behandelt.
Das System der Ephemeridenhelligkeiten der kleinen Planeten (Mitteilungen der Landessternwarte Heidelberg‐Königstuhl Nr. 115)
Authors: Pohl E.
Published: July 2007

Die an der Heidelberger Sternwarte angewandte Methode von Helligkeitsschätzungen kleiner Planeten auf photographischen Aufnahmen wird beschrieben und deren Genauigkeit untersucht. Von 32 kleinen Planeten wurden in Heidelberg lichtelektrische Helligkeitsmessungen gleichzeitig mit photographischen Aufnahmen vorgenommen. Mit Hilfe der lichtelektrischen Helligkeiten von 48 kleinen Planeten wird eine Beziehung zwischen dem in den Ephemeriden kleiner Planeten benutzten Helligkeitssystem einerseits und dem UBV‐System von JOHNSON UND MORGAN sowie dem internationalen photographischen System andererseits abgeleitet.
Bahnbestimmung mittels harmonischer Analyse der Doppelsterne RST 321 UND RST 3442
Authors: Wieth‐Knudsen N.
Published: July 2007

Die unten gegebenen Bahnbestimmungen zweier Doppelsterne sind nach dem vom Verfasser [1], [2] entwickelten Verfahren durchgeführt. Die hier verwendeten Bezeichnungen sind diejenigen der zitierten Arbeiten, und auch die Anordnung der Tafeln ist, mit ein wenig Vereinfachung, dieselbe wie dort.
Mikrometermessungen von Doppelsternen (Veröffentlichungen der Sternwarte München Bd. 5 Nr. 11)
Authors: Heintz W. D.
Published: July 2007

Diese Liste enthält 1697 visuelle, am 11‐zölligen Münchner Refraktor ausgeführte Messungen von 340 Objekten. Die Diskussion der systematischen Fehler ist vorläufig; die Messungen sind unkorrigiert tabuliert. Für ADS 12 557 wird eine Kreisbahn gegeben und bei ADS 16638 die Identifikation berichtigt.
Vier visuelle Doppelsternbahnen (Veröffentlichungen der Sternwarte München Bd. 5 Nr. 8)
Authors: Heintz W. D.
Published: July 2007

Für die vier Systeme ∑ 2315 = ADS 11 334, ∑ 13 = ADS 207, ∑ 1423 = ADS 7721 und ∑ 2281 = ADS 11 111 werden Elemente, dynamische Parallaxen, die benutzten Normalörter mit ihrer Darstellung und Ephemeriden mitgeteilt.
Zur Entdeckungsmöglichkeit von intergalaktischen Wolken
Authors: Schmidt K Arl‐Heinz
Published: July 2007

Unter bestimmten Annahmen über die Rate der Entstehung von Sternsystemen wird die Zahl der intergalaktischen Wolken in der Raumeinheit abgeschätzt. Daraus ergibt sich für verschiedene Beobachtungsmethoden die Zahl der beobachtbaren intergalaktischen Wolken. Es zeigt sich, daß die Entdeckungswahrscheinlichkeit im allgemeinen sehr gering ist. Den meisten Erfolg verspricht die Beobachtung der 21 cm‐Linie, wenn angenommen wird, daß der überwiegende Teil des Wasserstoffs einer intergalaktischen Wolke neutral ist.

Die Entfernung der von HOFFMEISTER gefundenen Wolke liegt zwischen 120 kpc und 1.15 Mpc, wenn ihre Masse zwischen 1 · 109 und 3 · 1011 𝔪⊙ angenommen wird.
Über einen eruptiven Veränderlichen in Hercules
Authors: Dorschner J. , Friedemann R.
Published: July 2007

On plates of the 60/90 cm Schmidt‐telescope of the Jena University Observatory taken 1967 June 29 up to August 2 an eruptive variable with a maximum magnitude B = 15m5 and an amplitude of at least 6 mag was found. There are indications that the object is a U Geminorum star of the subtype SW Ursae maioris.
Zur Wolkenstatistik des Planeten Mars
Authors: Schlosser Wolfhard
Published: July 2007

Die Verteilung der Wolken auf der Oberfläche des Planeten Mars in den Oppositionsjahren 1948, 1958, 1963, 1965 und 1967 wird graphisch dargestellt. Die Wolkenhäufigkeit pro Längengrad zeigt eine positive Korrelation mit der bei 21°.5 Nord gemessenen Radar‐Höhe.
Magnetic Neutron Stars. I. Static Field Configurations
Authors: Dautcourt G. , Fritze K.
Published: July 2007

The paper is the first in a series dealing with the structure of magnetic and rotating neutron stars including general relativistic effects. The geometry of fossile magnetic fields frozen in the highly conductive neutron star matter in a non‐rotating (or weakly rotating) star is studied. § 2 treats the general poloidal field in a vacuum outside the star. The geometry of magnetic fields within the star — whose matter is governed by a barytropic equation of state — is restricted by the condition that the magnetic force density should be curl‐free to maintain equilibrium (§ 3). Numerical results are obtained for a poloidal and a toroidal dipole field (§ 4).
Untersuchungen über die Struktur junger Sternhaufen und die Entwicklungsphasen ihrer Mitglieder. III. NGC 6611
Authors: Götz Woldemar
Published: July 2007

Untersuchungen über den Aufbau des Sternhaufens und das Verhalten astrophysikalischer Parameter hinsichtlich der Struktur zeigen, daß der Aufbau des Sternhaufens eng mit der kontinuierlichen Entstehung und Entwicklung seiner Mitglieder verbunden ist. Es wurde eine Zeitskala abgeleitet, die Aussagen über bestimmte Gebiete und über Entwicklungsphasen der Sterne gestattet.
Zur Spiralarmstruktur am südwestlichen Rand von M 31
Authors: Börngen F. , Astrophysik Zentralinstitut FÜR
Published: July 2007

Die Spiralstruktur am südwestlichen Rand von M 31 wird an Hand der Verteilung der dort bekannten OB‐Assoziationen diskutiert. Ausgehend von vier eindeutig definierten Spiralarmsegmenten wird nach dem Verlauf der Spiralarme gefragt. Es wird darauf hingewiesen, daß der äußerste Spiralarm am nördlichen Ende der großen Achse von M 31 eine merklich geringere Kernentfernung besitzt als der entsprechende Arm am südlichen Ende der großen Achse. Man darf deshalb am Nordostrand des Andromedanebels einige weitere, bisher unbekannte OB‐Assoziationen vermuten.
Steady State Distribution of an Ideal Cluster of Galaxies for Negative Cosmological Constants
Authors: Chen Mao C. , Sachdev Sushil K.
Published: July 2007

Die räumliche Verteilung eines idealisierten Galaxienhaufens im Gleichgewichtszustand wird für verschiedene negative kosmologische Konstanten numerisch berechnet, wobei die Haufenmitglieder als punktförmige Objekte gleicher Masse betrachtet werden. Dies stellt eine Erweiterung der klassischen isothermen LANE‐EMDEN‐Kugel für negative kosmologische Konstanten dar.
Possible Interpretations of B2 and 5C Quasar Candidate Counts and the “Cut off” in Quasar Density
Authors: Notni P.
Published: July 2007

Optical quasar candidate counts in the far reaching radio surveys B2 and 5C are consistent either with a luminosity function containing a high percentage of low luminosity objects and a cut off in quasar density or, more probably, with a normal number of quasars at high redshifts and a less steep luminosity function. The absence of high redshifted objects in currently available samples is to be expected of q0 ≈︂ o and if some of the few quasars observed at z>2.2 are exceptionally bright intrinsically and not typical for the bulk.
An interpretation of Pluto's light variation
Authors: Renschen C. P.
Published: July 2007

A first albedo distribution of a zonal region of Pluto's surface is presented which is based on the analysis of the observed light variations. Light scattering on the planet's surface is described by LAMBERT's law.
On the α‐effect for slow and fast rotation
Authors: Rüdiger Günther
Published: July 2007

This paper deals with the influence of global rotation on a special inomogeneous field of incompressible turbulence. All its deviations from homogeneity and isotropy may be described only by a constant gradient of turbulence intensity. Using a FOURIER representation we are able to determine the α‐effect for any given rotational rates and material constants. In the case of slow rotation our expressions show a strong similarity with those of other authors. Increasing angular velocities do not – as is to be assumed at first sight – suppress the production of mean electromotive force caused by turbulence. They rather lead to a two‐dimensionality of this e.m.f. with respect to the axis of rotation. It seems, therefore, that very fast rotation can not completely delete the dynamo instability.
A new strong emission line quasar with a redshift z = 0.189
Authors: Lorenz H. , Richter G. A. , Afanasjev V. L. , Lipovetsky V. A.
Published: July 2007

An object is described which has a redshift of z = 0.189.
Definitive orbit of minor planet (85) Io from observations 1865–1977 (Astronomisches Rechen‐Institut Heidelberg – Mitteilungen Serie B).
Authors: Schmadel L. D.
Published: July 2007

An improved orbit of minor planet (85) Io is determined from an analysis of all known observations over the 112 year period 1865 – 1977. Some 735 observations from 63 apparitions are recorded. A comprehensive bibliography of the observations is given as well as a discussion of the O–C residuals. The final solution, based on 548 accurate positions from 54 oppositions, yields a total rms value of 2.″61.
Nouvelle Determination des Elements Orbitaux de L'etoile Double Visuelle ADS 7203–σ2 UMA
Authors: Scardia M.
Published: July 2007

The orbital elements of the binary star ADS 7203 – σ2 UMa were determined with the method of KOWALSKY, by the use of 168 observations. These provisional elements were then corrected with the differential method of HELLERICH. At last the total mass of the system was calculated and the dynamical parallax was obtained with the method of BAIZE‐ROMANI.
EINSTEIN and MICHELSON The Context of Discovery and the Context of Justification
Authors: Stachel J.
Published: July 2007

The philosopher of science is not much intersted in the thought processes which lead to scientific discoveries; he looks for a logical analysis of the completed theory, including the relationships establishing its validity. That is, he is not interested in the context of discovery, but in the context of justification … it appears amazing to what extent the logical analysis of relativity coincides with the original interpretation by its author, as far as it can be constructed from the scanty remarks in EINSTEIN's publications. In contradistinction to some developments in quantum theory, the logical schema of the theory of relativity corresponds surprisingly with the program which controlled its discovery.
Photometric catalogue of Shakhbazian compact groups of galaxies. IV.
Authors: Stoll D. , Tiersch H. , Oleak H. , Macgillivray H. T.
Published: July 2007

The fourth part of the photometric catalogue of Shakhbazian compact groups of galaxies contains optical and geometrical properties of another 26 groups (Shkh 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333, 334, 335, 336, 337, 357). As in the previous papers photometric data were obtained from the COSMOS/UKST catalogue of the Southern sky with δ ± +2°30'. The survey of compact galaxy groups by Shakhbazian, Petrosian, Baier, and Tiersch is a basis for studying physical properties of such groups.
Photographic positions of Minor Planets
Authors: Debehogne H. , Scardia M. , Ghiringhelli D.
Published: July 2007

Photographic precise positions of 13 minor planets obtained with the G.P.O. astrograph at E.S.O. (La Silla, Chile) in September 1987 are given.
Non‐rigid rotation of solar spicules
Authors: Pishkalo M. I.
Published: July 2007

Hα profiles of chromospheric spicules computed for a variety of rotational behavior are compared with an observed profile, which was derived by averaging 11 Hα profiles taken near times of maximum spicule intensity. If turbulent velocity is small or equals zero, calculated profiles are in good agreement with the observed one under the conditions that rotation is non‐rigid (faster rotation further away from the axis of the spicule) and the source function decreases in the direction from the spicule axis to the periphery. The comparison of calculated and observed tilts of spicule spectra relative to the direction of dispersion seems to corraborate the non‐rigid character of spicular rotation.
Proper motions in the field of the globular cluster NGC 6934
Authors: Tucholke H.‐J.
Published: July 2007

We measured relative proper motions with a typical accuracy of 1.0 milliarcsec/year (mas/a) for 2000 stars in a 1°4 × 1°4 field around the low‐latitude globular cluster NGC 6934. Four plates taken with the Bonn double refractor, spanning an epoch difference of 62 years, were digitized completely. Within the tidal radius of the cluster, we find 106 stars with proper motion errors less than 5 mas/a. Membership probalilities are computed taking into account the individual proper motion errors and the radial distances to the cluster centre. We derive the mean relative proper motion of NGC 6934 using stars with high membership probabilities from radial velocities (Smith and Bell 1986) or from their location in the colour‐magnitude diagram (Harris and Racine 1973). The relative proper motions of four Hipparcos stars in the field will be used to obtain the absolute proper motion of NGC 6934 once the extragalactically calibrated Hipparcos Output Catalogue is available.
The true rotational period of the Ap star HD 193722 = V 1584 Cyg
Authors: Hildebrandt G. , Scholz G. , Lehmann H. , Panov K.
Published: July 2007

Photometric observations of the Ap star HD 193722 give unambiguous proofs for a rotational period of P=8.5297 days in contradiction to the earlier found value of P=1.13316 days. Spectroscopic measurements yield a line width equivalent to the value v sin i=44.5 km/s. Both findings show convincingly that HD 193722 is an evolved Ap star with a position in the giant region of the HR diagram. This place falls into a domain occupied by the hypothetic Maia sequence.
The charged particle distribution due to emission in a magnetic field
Authors: Gunko Y. F. , Ponomaryv M. G.
Published: July 2007

Charged particles emission in a magnetic field on the basis of Boltzman equation with source term is studied. The work develops the results of Narasimha (1962), where the neutral gas expansion into a vacuum is studied. The different specific cases of emission are given for moving sources. The results may be of use when we study phenomena which happen in plasma close to the Earth and in space, as well as for studies of phenomena which take place due to moving satellites in the ionosphere and in interplanetary or interstellar plasma.
Solar corona photometry by electropolarimetric and CCD observations during the eclipse of July 11, 1991
Authors: Kulidzanishvili V. I. , Georgobani D. G.
Published: July 2007

The observational data of the solar corona obtained during the solar eclipse of July 11, 1993, using both a electropolarimeter (EP) and a CCD matrix were processed. Using these data the photometry of the solar corona was carried out. The results of EP data were compared with those of the CCD data. It must be noticed here that the CCD data give us only the characteristics of the inner corona, while the EP data show the features of both the inner and the middle corona up to 4 solar radii.

The standard flattening index ϵ was evaluated from both data. The dependence of ϵ on the distance from the solar limb was investigated. Three‐dimensional images of the coronal intensity distribution for different spectral lines are shown. Isophotes in Na and Ca lines with unusual features are plotted. Based on these data some ideas and conclusions on the type of the solar corona and the physical conditions in it are presented.
Construction of a diameter‐limited sample of galaxies in the northern sky. The catalogue
Authors: Bardelli S. , Zucca E.
Published: July 2007

In order to understand if the differences between the SSRS of Da Costa et al. (which is diameter‐limited) and the CfA survey (which is magnitude‐limited) are real or induced by the different selection criteria, the CfA survey has been directly compared with a diameter‐limited sample covering the same region of the sky (UDLS, Bardelli et al. 1991, Zucca et al. 1991).

In this paper we present the data for the galaxies in the UDLS sample, in an updated version which collects velocity information from the literature until June 1993, leaving us with a velocity completeness better than ˜ 95%.
The difference between the nearby galaxies and the Virgo cluster
Authors: Schmidt K.‐H. , Boller Th.
Published: July 2007

The sample of galaxies within 7 Mpc has been compared with that of the Virgo cluster in order to find new and confirm already known differences which may be caused by the environment. The well‐known morphology‐density relation is found to be valid not only for luminous galaxies but also for faint objects. The differences in the global luminosity functions are mainly caused by the different composition of the samples, whereas the luminosity functions of narrow morphological subgroups, with the exception of the irregulars, probably are not dependent on the density or on other quantities. The already observed HI‐deficiency of the interstellar medium of the Virgo cluster spirals has been confirmed. There is a steep drop of this quantity with increasing distance from the dominant galaxies M 87 and M 49. The interstellar dust masses of Virgo cluster spirals and irregulars have been estimated from far‐infrared fluxes. These data have been combined with the HI masses in order to obtain the gas‐to‐dust ratios, which come out to be smaller by a factor of 4 for the Virgo cluster spiral galaxies than for the nearby systems, on the average. The gas‐to‐dust ratio is strongly correlated with the HI‐deficiency. These results support the concept of the ram pressure of the intracluster medium on the spiral galaxies in the core of the Virgo cluster.
The additional radiation of Cyg X‐1 at primary minimum
Authors: Voloshina I. , Lyuty V. M.
Published: July 2007

New UBV‐photoelectric observations of the well‐known massive X‐ray binary system Cyg X‐1/V 1357 Cyg are obtained near the primary minimum. The detailed analysis of these observations confirms the existence of additional blue radiation which appears as a narrow peak with an amplitude of 0.01–0.02 mag near phase 0.00 on the light curve (the superior conjunction of the relativistic component), firstly detected by Lyuty (1985). This emission does not appear at every orbital cycle. The appearance of this narrow peak of additional blue radiation on the light curve of Cyg X‐1 can be explained as the radiation of relativistic electrons in the disturbed magnetic field of the optical star in frames of the model proposed by Ikhsanov and Fabrika (1990).
Photographic positions of Minor Planets
Authors: Debehogne H. , Scardia M. , Ghiringhelli D.
Published: July 2007

Photographic precise positions of 16 minor planets obtained with the G.P.O. astrograph at E.S.O. (La Silla ‐ Chile) in January 1988 are given.
The influence of the surroundings on the morphology of galaxies
Authors: Mahtessian A. P. , Movsessian V. H. , Khachikian E. Ye. , Tiersch H.
Published: July 2007

The characteristics of galaxies within galaxy groups are investigated as a function of the surroundings. It is shown that the relative number of the galaxies with different morphological type is correlated with the number of members within the group, but the fraction of E+S0 galaxies does not depend on the mean‐pairwise distance between the galaxies, the density of the luminous matter as well as the velocity dispersion in the group.
On the period changes of RR Lyrae variables in the globular cluster M3
Authors: Wenzel W.
Published: July 2007

O – C diagrams of 78 RR Lyrae variables of the years 1963 to 1978 were used to investigate their comparability with the diagrams of 1895 to 1963. Only 5% have been proved to show a fundamentally deviating trend of the period change.
Radial velocities of the components of the Trapezium‐type multiple systems
Authors: Javakhishvili G. Sh. , Salukvadze G. N.
Published: July 2007

From 1988 to 1989 radial velocities of 76 components of 46 Trapzium‐type multiple systems have been measured with the 125‐cm reflector of the Abastumani Astrophysical Observatory. In Table 1 a list of observations is given, containing the mean values of radial velocities, velocities of axial rotation, the halfwidth of contours and equivalent width.
Identification of D3 and Hα spicules
Authors: Khutsishvili E. V.
Published: July 2007

Basing on the analysis of observational material obtained with the 53‐cm coronagraph in Abastumani, the author concludes that chromospheric spicules in hydrogen and helium lines are one and the same formation. Besides, it should be noted that, as a result of radial velocity measurements, it was found that hydrogen and helium D3 lines are emitted from different areas of the same spicule.
Stochastic forces in space plasmas with ion‐acoustic and lower‐hybrid‐drift turbulence
Authors: Meister C.‐V.
Published: July 2007

A Langevin equation for charged particles in a plasma with electrostatic turbulence is developed from first principles and in consistency with the kinetic theory in polarization approximation. For the case of ion‐acoustic and electrostatic lower‐hybrid‐drift turbulence approximate expressions for the space‐time spectral density of the wave energy are given and estimates of the intensities of the stochastic wave forces are made. The application is done for the plasmas of the earth's magnetosphere, the solar wind and solar flares.

It seems, that ion‐acoustic and electrostatic lower‐hybrid‐drift waves can contribute to electron chaotization in different regions of the space plasma.
Positional and photometric CCD observations of the comet Shoemaker‐Levy 9
Authors: Kiladze R. , Kvernadze T. , Ogadze G. , Inasaridze R.
Published: July 2007

Positional and photometric CCD observations of the comet Shoemaker‐Levy 9 fragments were carried out at the Abastumani Astrophysical Observatory. Up to 15 named fragments were detected and their equatorial coordinates and magnitudes are reported. CCD frames were processed using DAOPHOT II. The internal precision of reference star positions down to 18m is 0.″7 and the mean error of photometry does not exceed ±0.3 mag.
Beobachtungen Kleiner Planeten. II
Authors: Börngen F. , Kirsch K.
Published: July 2007

Es wird eine übersicht gegeben über die im Jahr 1981 auf Tautenburger Schmidtaufnahmen gefundenen Kleinen Planeten. Es wurden 294 Objekte entdeckt und für sie 614 Positionen gerechnet.
Approximate Solutions of the Equations of Motion of a Charged Particle in the Field of a Magnetic Dipole
Authors: Kustaanheimo P. E. , Tutein J.
Published: July 2007

Three differential equations of the first order (26)—(28) which determine the trajectory are deduced. An approximate integration by means of elementary functions yields a set of formulas (in chapt. 13. Conclusions) that give a „window”︁ in the sky inside of which the radiation point of a high energy cosmic ray (monotonely bent in the magnetic field) must lie.
BIANCHI‐I‐Kosmen der BRANS‐DICKE‐Theorie für das Vakuum
Authors: Dyllong U.
Published: July 2007

The field equations of the BRANS‐DICKE theory are solved for a vacuum with the aid of a space‐time metric of BIANCHI‐I‐type. Two solutions are found. One of them corresponds to a generalization of the flat de SITTER‐universe. On the other side we have obtained the KASNER‐like solution on the basis of original the version of BRANS‐DICKE theory.
Singularity‐free static centrally symmetric solutions of some fourth order gravitational field equations
Authors: Fiedler B. , Schimming R.
Published: July 2007

Die von TREDER vorgeschlagenen Gravitationsfeldgleichungen 4. Ordnung mit einer Linearkombination des Bachtensors und des Einsteintensors auf der linken Seite besitzen statische zentralsymmetrische Lösungen, welche in einer Umgebung des Symmetriezentrums analytisch und nicht flach sind.
Astronomische Längen‐und Breitendifferenzen der Basisobservatorien Irkutsk, Potsdam und Simeiz (Mitteilungen des Zentralinstituts für Physik der Erde, Nr. 1180)
Authors: Höpfner J.
Published: July 2007

In den Jahren 1980—1981 wurden auf den Stationen Irkutsk, Potsdam und Simeiz astronomische Beobachtungen an einem transportablen DANJON‐Astrolab zwecks Bestimmung von Längen‐ und Breitendifferenzen ausgeführt. — Es wird über die durchgeführten Beobachtungen und ihre Auswertung berichtet, wobei auch die benötigten Formeln zur astronomischen Längen‐ und Breitenbestimmung angegeben werden. Die erhaltenen Längen‐ und Breitenwerte werden eingeschätzt. Hiernach dient die gewogene Mittelung dazu, sie schrittweise zu verdichten. Dabei werden sie auf systematische Gruppendifferenzen und persönliche Fehler hin untersucht. Abschließend werden die Längen‐ und Breitendifferenzen unter Berücksichtigung der persönlichen Gleichungen der Beobachter abgeleitet. Ihre Genauigkeiten betragen zwischen ±0,0020 s und ±0,0028 s bzw. ±0,013”︁ und ±0,017”︁.
Transits of Mercury: Results of Belgrade Observations in 1970 and 1973
Authors: Protitch‐Benishek V.
Published: July 2007

Photographische Beobachtungen der Merkurdurchgänge vor der Sonne 1970 und 1973 an der Sternwarte Belgrad wurden zur Ermittlung der scheinbaren Halbmesser von Sonne und Merkur benutzt. Die mittleren Werte des Sonnenradius, reduziert auf die Längeneinheit, sind um ca. 1.3 größer als die Auwersschen Werte, wohingegen die Werte für den Merkur mit denen von LE VERRIER übereinstimmen.

Für die Sonnenparallaxe wurden folgende Werte erhalten: 8.800 ± 0.008 (1970) und 8.788 ± 0.032 (1973) und als gewogenen Mittelwert: πs = 8.794 ± 0.013.
Values of the Atmospheric Density at 280 km Obtained from Spin Drag Data of COSMOS 54 Rocket
Authors: Mioc V.
Published: July 2007

A set of atmospheric density values at a height of 280 km between MJD 39675—39702 is determined by using the spin drag data of COSMOS 54 rocket. For this purpose photometric observations from five tracking stations and data about the satellite and its orbital evolution were used. The density values determined firstly at the perigee height were reduced at a standard height of 280 km and then compared with density values determined by using orbital drag data of this rocket at the same height and in the same time interval. The agreement between the two sets of densities (determined by using two different methods) is satisfactory.
On‐line‐Steuerung eines lichtelektrischen Sternphotometers
Authors: Reimann H.‐G. , Pfau W. , Stecklum B.
Published: July 2007

Die on‐line‐Steuerung eines photonenzählenden Photometers mit dem Kleinsteuerrechner KSR 4100 in der erweiterten Sprache INKA wird beschrieben. Charakteristische Größen des Photometers (Farbgleichungskoeffizienten, Totzeit) sind angegeben. Dabei erfolgte die Ermittlung der Totzeit mit einem neuen Verfahren unter Ausnutzung der Photonenstatistik bei Messungen mit hoher Zeitauflösung (1 ms).
Faint Blue Galaxies in the Virgo Cluster Region
Authors: BÖrngen F.
Published: July 2007

Finding charts, coordinates, B magnitudes, and U – B color estimates are given for 110 faint blue galaxies located near the centre of the Virgo cluster of galaxies. The galaxies have been found by blinking on plates taken with the Tautenburg 52 inch SCHMIDT telescope.
The Close Encounter of Comet Wild 3 with Jupiter
Authors: Buffoni L. , Carta F. , Manara A. , Scardia M.
Published: July 2007

The periodic comet Wild 3 had in May 1977 a close encounter with Jupiter. The motion and magnitudes of Wild 3 before and after this event are examined.
Observations of Minor Planets
Authors: Kroll P.
Published: July 2007

151 positions of 32 minor planets found on plates taken from 1979 to 1983 with the astrograph 400/1950 mm of Sonneberg Observatory are given.
The binary nature of the magnetic star β CrB
Authors: Oetken L. , Orwert R.
Published: July 2007

The radial velocity of the binary star β CrB was reinvestigated to look for the hypothetical third body, suggested by NEUBAUERS results. Under the assumption that a systematic difference of 1.4 km/sec between NEUBAUERS results from 1931–43 and ours from 1971–83 is of instrumental origin, the radial velocities of both epochs can be well represented with the same orbital elements: thus the probability for the existence of a third component in the system is reduced. The eccentricity and the angle of periastron passage of the visual orbit, derived from published speckle interferometric measurements, agree very well with the corresponding elements of the spectroscopic orbit. For the masses of the components those of giant resp. subgiant stars of type A8 and F5 are found. The geometry of the binary β CrB with a magnetic star as the primary component is demonstrated.
Observer dependence of past light cone initial data in cosmology
Authors: Dautcourt G.
Published: July 2007

We discuss some properties of the initial data introduced in previous articles to study the past light cone initial value problem in cosmology. A parametrization of the conformal cone metric (the geometrical part of the initial data) is proposed which is closely related to astronomical observations of image distrotions of distant extragalactic objects. The quantities used here as initial data have simple transformation properties under a Lorentz rotation of the oberver.
On the existence of periodic orbits in a nearly axisymmetric galaxy
Authors: Caranicolas N.
Published: July 2007

Assuming that the potential field on the plane of symmetry of a nearly axisymmetric galaxy is a polynomial of the fourth degree, we study the conditions of existence and stability of the main types of periodic orbits. We verify the theoretical results by numerical calculations.
Photometric investigations of compact galaxies
Authors: Börngen F. , Kalloghlian A. T.
Published: July 2007

No exact definition of compact galaxes with regard to their degree of concentration exists up to now. 169 objects visually selected by ZWICKY respectively BÖRNGEN and KALLOGHLIAN in the field ZwCl 1710.4 + 6401 are analysed photometrically and morphologically. The brighness profiles are determined by means of equidensities calibrated into intensities. The different parts of these profiles are investigated with regard to their utility of an objective description of compact galaxies. Whereas the halo is not suitable, a classification is practicable by means of the gradient G of the middle part of the profile. Especially, it is shown that the (lg Imax, m)‐diagram is well suited to represent the compact galaxies. In an interval of some magnitudes in which the density of star images is not yet saturated the positions of stars and compact galaxies differ significantly. The star positions obey a linear relation which is used for the calibration of our method and for the derivation of the plate constants. By means of the characteristic quantity m0 and the compactness k one gets a quantitative characterization of compact galaxies and a subdivision into the classes K = 1, 2, and 3. Extreme compact galaxies (K = o) are difficult or not at all discernible from stars, galaxies of the class K = 4 are no more compact.
Photometry of groups of galaxies. I
Authors: Richter G. M. , Vennik J. , Struve W.
Published: July 2007

Photometric data (magnitudes, radii, profiles) for galaxies in the field of 7 nearby groups of galaxies are measured by photographic surface photometry. Most of them are dwarf galaxies.
Some results of model calculations of the solar S‐component radio emission
Authors: Krüger A. , Hildebrandt J.
Published: July 2007

Numerical calculations of special characteristics of the solar S‐component microwave radiation are presented on the basis of recent sunspot and plage models. Quantitative results are discussed and can be used for the plasma diagnostics of solar active regions by comparisons with observations with high spatial and spectral resolution
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The possibility of generalized applications to magnetic stars and stellar activity is briefly noted.
On tidal radius determination for a globular cluster
Authors: Ninkovica S.
Published: July 2007

A tidal radius determination for a globular cluster based on its density minimum, which is caused by the galactic tidal forces and derivable from a model of the Galaxy, is proposed. Results obtained on the basis of the Schmidt model for two clusters are in a satisfactory agreement with those obtained earlier by means of other methods. A mass determination for the clusters through the tidal redius, when the latter one is identified with the cluster perigalactic distance, yields unusually large mass values. Probably, the tidal radius should be identified with the instantaneous galactocentric distance. Use of models more recent than the Schmidt one indicates that a globular cluster may contain a significant portion of an invisible interstellar matter.
New results on large‐scale structures
Authors: Kalinkov M. , Stavrev K. , Kuneva I.
Published: July 2007

A new version of the magnetic‐tape catalog of ABELL clusters of galaxies is used to obtain redshift estimators and to generate two samples of clusters. A procedure for searching for superclusters of galaxies is applied and the results are given in tabular and graphic form. For a lmited homogeneous sample (distance 60–275 Mpc, galactic latitude B > 35°), 12 multiplets, having member clusters with known redshifts, are found. It is shown that the spatial covariance function for rich clusters has the form ξ = (r0/r)γ with r0 = 22.4 ± 1.8 Mpc and γ = 1.90 ± 0.25 for 3 Mpc ≲ r ≲ 80 Mpc.
Galaxy photometry in the Virgo cluster. II
Authors: Fritze K.
Published: July 2007

For two fields of the Virgo cluster of galaxies a photometry in B, V, and R has been performed. A total of 72 galaxies has been identified and their magnitudes and diameters have been determined.
Investigation of clusters of galaxies. I. Explanation of photometric scale of errors by light diffusion in a photographic emulsion
Authors: Baier F. W. , Ziener R.
Published: July 2007

A photographic photometry in B and V was performed for 326 galaxies in the central field of the Coma cluster. We found an explanation (diffusion of light in the emulsion according to an earlier investigation of ZIENER) for the systematic deviation between the results from ROOD and BAUM and from GODWIN and PEACH in the V pass band. We conclude that the photometry of ROOD and BAUM is true. Diffusion also can explane the results of FONG, GODWIN, and METCALFE.
Boundary behaviour of accretion disks determined by gravity induced cooling near the black hole
Authors: Paul H. G.
Published: July 2007

In the framework of thin, rigorous relativistic accretion disks the inner boundary behaviour is studied taking into cosideration the internal energy of the disk plasma. Consuming the internal energy stored in the accretion flow the disk forms a cusplike wall in the effective gravitational potential; the disk matter is raised on higher levels of the angular momentum by cooling simultaneously. This gravity induced cooling leads to a rigorous braking of the radial accretion flow. There is a steep, inner boundary with a very small gap very close at the orbit of last bound motion of test matter. Especially natural boundary conditions can be imposed in contrast to the boundary value problem in the divergent, relativistic standard models.
Eléments orbitaux corrigés de l'étoile double visuelle ADS 9626 BC—STF 1938
Authors: Scardia M.
Published: July 2007

Orbital elements of the visual binary star ADS 9626 BC are given. The dynamical parallax and total mass of the system have been calculated.
Accretion disks in bimetric theory of gravitation. A strong field test of general relativity?
Authors: Paul H. G.
Published: July 2007

The sensitivity of accretion disk models with respect to its inner boundary conditions, being located in the strong gravity region of a highly compact central body, is used to discuss a possibility of strong field tests of gravitation via compact source observations. Within the bimetric theory of gravitation the optically thin bremsstrahlung model is calculated as an example for this possibility. Using this model to describe the innermost region of the “bimetric disk”, significant differences with respect to the corresponding results in Einstein's theory were found. The more massiv and compact “bimetric disk” radiates softer with higher luminosity.
Entropy production during an isothermal phase transition in the early Universe
Authors: Kämpfer B.
Published: July 2007

The isothermal confinement transition in the early Universe is treated. For the bag model equation of state a very large entropy production is found at sufficiently large supercooling. This tremendous entropy increase can significantly dilute the primordial monopole or baryon to entropy ratio.
S‐matrix approach to interacting quantum field theory in curved space‐time1)
Authors: Audretsch J.
Published: July 2007

We give an analysis of mutually interacting quantum fields in given unquantized Robertson‐Walker universes using an S‐matrix approach. Transition probabilities and particle number mean values are discussed in detail with the intention to read off the underlying physics and to apply them to scattering and decay processes.
Quark‐Hadron transition in cosmology
Authors: Bonometto S. A.
Published: July 2007

The present understanding of the cosmological quark‐hadron transition is briefly reviewed, trying to outline the physical questions which are related to measurable astrophysical parameters. In particular the possible impact of baryon number inhomogeneities on primeval nucleosynthesis is discussed.
On the concept of gravitons in General Relativity Theory
Authors: Von Borzeszkowski H.‐H.
Published: July 2007

Discussing three arguments which verify the quantum‐field hypothesis in electrodynamics, it is shown that in GRT analogous investigations demonstrate the opposite, namely a limitation of this conception to the low‐frequency region.
Einstein‐Gleichungen mit Zusatztermen 4. Ordnung und Raum‐Zeit‐Modelle vom Bianchi‐Typ I
Authors: John R. W.
Published: July 2007

Die Einsteinschen Gleichungen, verallgemeinert durch additive Terme, die Ableitungen der Metrik bis zur 4. Ordnung enthalten, werden im Vakuum‐Fall auf kosmologische Raum‐Zeit‐Modelle vom Bianchi‐Typ I angewandt.
Definitive orbit of minor planet (29) Amphitrite from 91 oppositions 1825‐‐1985 and a new determination of the mass of Jupiter
Authors: Schmadel L. D.
Published: July 2007

Minor planet (29) Amphitrite will serve as a target for the first asteroid flyby with NASA spacecraft Galileo on December 6, 1986. It also represents a first priority object for solar system observations with the ESA astrometry satellite Hipparcos which is scheduled to be launched in 1988. In order to meet the high astrometric accuracy requirements, a definitive orbit based on 1,577 observations from 91 apparitions covering the time span 1825 to 1985 is evaluated. (29) Amphitrite moves near to the 3:1 resonance to Jupiter and seems particularly suited for a new determination of the mass of the Jupiter system. A most probable mass value of 1/(1047.369±0.029) solar masses is obtained and the relaibility of this result is discussed.
Distribution of luminous blue stars in M33
Authors: Ivanov G. R. , Kunchev P. Z.
Published: July 2007

M33 luminous stars with MV ≲ ‐7 and U‐‐B < o are selected in this paper. The spatial distribution of the stars shows a good agrement with the associations and HII regions. However HII regions are absent in the three youngest associations in M33 (t ≈ 5 ÷ 7 × 10yr). It is supposed that the true distance modulus of M33 derived from the brightest blue stars is 24.2. An age gradient across the arms is absent. The spiral arms outlined by the luminous stars differ form those in M31. They are diffuse and wide. The multiarm features of M33 support the stochastic self‐propagating model.
Die Hadamard‐Konstruktion Greenscher Funktionen auf gekrümmter Raum‐Zeit: Physikalische Zusammenhänge und explizite strenge Resultate
Authors: John R. W.
Published: July 2007

Zunächst wird die mathematisch‐physikalische Bedeutung kovarianter Greenscher Funktionen im relativistischen Gravitationsfeld‐gemäß EINSTEIN: auf gekrümmter Raum‐Zeit‐in Verbindung mit ihrer Konstruktion nach HADAMARD erörtert. Sodann werden für den Fall einer allgemeinen statischkugelsymmetrischen Raum‐Zeit die Konstruktionsgleichungen für eine skalare Greensche Funktion in symmetrieangepaßte Form gebracht, was einen günstigen Ausgangspunkt zur expliziten Berechnung der Hadamard‐Bauelemente gibt. Bei Anwendung der so gewonnenen Grundgleichungen auf eine spezielle einparametrige Schar von Modell‐Metriken gelingt es, bis zur expliziten strengen Berechnung von Schweifterm‐Koeffizienten einer masselosen Greenschen Funktion vorzudringen; sie sind zugleich Koeffizienten in der Schwinger‐DeWitt‐Entwicklung des Feynman‐Propagators zur entsprechenden Ruhmasse enthaltenden Klein‐Gordon‐Gleichung auf gekrümmter Raum‐Zeit.
The interstellar 217 nm band: a third catalogue of equivalent widths
Authors: Friedemann C. , Röder U.‐K.
Published: July 2007

Using the data obtained with the ultraviolet photometer in the Astronomical Netherlands Satellite the equivalent widths of the interstellar 217 nm band as well as other parameters characterizing the behaviour of the continuous interstellar extinction in the wavelength region of the band have been derived for 790 O, B stars with colour excesses E(B ‐ V) ≥ 0·4 mag.
The cycle length of the U Geminorum star HT Cassiopeiae
Authors: Wenzel W.
Published: July 2007

The mean cycle length of the catalysmic binary HT Cas, which is remarkable because of the shortness of its orbital period, has been determined as 400d±50d. The hitherto assuixed value of 30d proved unfounded. Some aspects arising when classifying long‐cycle objects and SU Ursae Majoris variables are pointed out, a s well as the relation between large cycle length and small accretion rate.
Determination of gravitational potential for axisymmetric mass‐distribution. IV. Some hydrodynamical test results
Authors: Tschaepe R.
Published: July 2007

Economy of computing the gravitational potential for quasihydrostatic and hydrodynamical models, respectively, (axisymmetric mass distribution in spherical coordinates) suggests the application of the successive overrelaxation method in spherical coordinates, because a good approximation of potential from a previous cycle leads to the wanted solution by means of only few iterations.
Monopole abundance from first‐order GUT phase transition of the early Universe
Authors: Bagoly Zs. , Lukács B. , Paál G.
Published: July 2007

Monopole annihilation and pair creation are investigated in a first order GUT symmetry breaking phase transition without inflation. It is found that even with complete initial monopole suppression, some monopoles are inevitably produced during the transition. According to this, some constraints are obtained for initial and equilibrium monopole densities in order to be compatible with the present observational limits even without inflation.
Comparing selfinteracting scalar fields and R + R3 cosmological models
Authors: Schmidt H.‐J.
Published: July 2007

We generalize the well‐known analogies between m2φ2 and R + R2 theories to include the selfinteraction λφ4‐term for the scalar field. It turns out to be the R + R3 Lagrangian which gives an appropiate model for it. Considering a spatially flat Friedman cosmological model, common and different properties of these models are discussed, e. g., by linearizing around a ground state the masses of the resp. spin 0‐parts concide. Finally, we prove a general conformal equivalence theorem between a Lagrangian L = L(R), L′L″ ≠ 0, and a minimally coupled scalar field in a general potential.
On the mechanism of the “Noisar” phenomenon in magnetic close binary systems
Authors: Andronov I. L.
Published: July 2007

The mechanisms of “Noisar” phenomenon in AM Herculis‐type stars are discussed. In an accretion column above the surface of the magnetized degenerate star the instability of some types may be excited, such as axi‐symmetrical quasi‐periodical penetration of the low‐density “bulks” from the column axis to the outer parts; “boiling” with “bulks” moving inside or outside the column; “tornado” with low‐density region rapidly rotating around the column axis; “switchings” of the accretion from one half of the “polar cap” to another and vice versa. The oscillations of different plasma clots (“spaghetti”) may interfer causing flux changes as well. Such “Noisar” oscillations appear in different regions of the accretion column (at the upper shock and near the column base, respectively), so hard and soft X‐ray fluxes might not have correlation in their variability. The observations are in qualitative agreement with the models.
V 361 Lyrae: An exotic binary system with a “Hot Spot” between the components?
Authors: Andronov I. L. , Richter G. A.
Published: July 2007

A phenomenological model for V 361 Lyr is proposed. Probably it is a binary system which consists of a mass accreting primary star with mass of about M1 ≈ 0·81 M⊙ and radius R1 ≈ (6.1 ± 0·4) · 1010 cm and a mass losing secondary with about M2 ≈ 0·77 M⊙ and R2 ≈ 5.8 · 1010 cm. The secondary fills its Roche lobe, but the primary is something smaller than this lobe, contrary to the models of W UMa‐type systems. So the hot spot appears in the atmosphere of the primary, but not in a disk, like in cataclysmic variables. The luminosity of the hot spot, L = (6‐15) · 1032 erg/s, is large enough to be the main emission source of the system in visible light. So phenomenologically the object may be somewhat between W UMa‐type stars and cataclysmic variables.
The interpretation of oscillations in sunspot umbrae
Authors: Žugžda Y. D. , Locāns V. , Staude J.
Published: July 2007

We review possibilities for an interpretation of oscillations observed in several period bands (3 min., 5 min., 20 min.) and at different heights in sunspot umbrae. At subphotospheric depths two independent resonators are acting: A resonator for slow, quasi‐transverse waves can explain the lifetimes of bright umbral dots (≥20 sec.), while a resonator for fast (acoustic), quasi‐longitudinal waves could result in the 5‐min. oscillations. The acoustic resonator strongly couples with the slow‐mode longitudinal resonator at photospheric and chromospheric heights, the latter produces the resonance peaks in the 3‐min. period band. The whole scheme of resonance levels generalizes and corroborates a chromospheric resonator model earlier proposed by the present authors. Comparisons with alternative models and recent measurements show that the present model most naturally explains the majority of observed data.
The LMC supernova (SN 1987 A) as a probe for the outcome of stellar collapse
Authors: Haubold H.‐J. , Gottlöber S. , Mücket J. P. , Müller V. , Kämpfer B.
Published: July 2007

Implications from the available information on the supernova SN 1987 A are discussed for the supernova models. We derive an upper bound of 10–25 eV for the neutrino rest mass.
Phenomenological models of cosmic phase transitions
Authors: KÄmpfer B.
Published: July 2007

Phenomenological models of cosmic phase transitions are presented. We consider phase transitions (i) with fixed initial and final states or (ii) in the relaxation time approximation. The Friedmann equations are solved and the entropy production due to the non‐equilibnum transition is calculated for a bag model equation of state. Numerical examples are given for the confinement transition, but the formulae presented apply directly to the GUT transition, too.