ADS BibCode:
1983Msngr..34....1E
Author(s)/Affiliation(s):
Enard, D.; Swings, J.-P.
AA(Head of the VLT Project Group) AB(Chairman of the VLT Astronomy Advisory Committee)
Abstract:
As emphasized unanimously at the time of the Cargese workshop" a Very Large Telescope (VLT) project is of vital importance to the future vigour of European astronomy. The table given below shows indeed that "competing" projects exist in the US, UK, USSR, all of which are to be completed within about 10 years. The Space Telescope is indicated in the same table for comparison, in order to stress its high cost and its size of "only" 2.4 metres. It is also very important to keep in mind that the Space Telescope and future large ground-based telescopes are to be considered as complementary, not as competitors.

ADS BibCode:
1983Msngr..34....3M
Author(s)/Affiliation(s):
Mouchet, M.
AA(Meudon, Observatoire, Meudon, Hauts-de-Seine, France)
Abstract:
Attention is given to the characteristics of the four 'interemediate polar' objects exhibiting optical pulsations, AO Pisc, V1223-Sgr, H2215-086, and 3 AO729 + 103. After interpreting their pulsation phenomena, a discussion is conducted on the existence in these objects of an accretion disk and an accretion column. H2215-086 is singled out for detailed description. The proposed interpretation of the pulsations requires a white dwarf that is sufficiently magnetized to favor an anisotropic accretion along the magnetic field.

ADS BibCode:
1983Msngr..34....3.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1983Msngr..34....6.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
276. G. Chincarini: HI Content in Cluster and Supercluster Galaxies. COSPARIIAU Symposium in Rojen, Bulgaria. September 1983.

ADS BibCode:
1983Msngr..34....7H
Author(s)/Affiliation(s):
Hensberge, H.; Maitzen, H. M.; Weiss, W. W.
AA(Astrofysisch Instituut, Vrije Universiteit Brussel) AB(Institut für Astronomie, Universität Wien) AC(Institut für Astronomie, Universität Wien)
Abstract:
On October 5 and 6, 1983 the European Working Group on Chemically Peculiar Stars (CP Stars, formerly called Ap Stars) convened its 10th meeting at the ESO headquarters in Garching. After the opening, Dr. Herman Hensberge from the Vrije Universiteit Brussel gave a seminar to the ESO audience on "Progress of Ap research at ESO". In what follows we shall provide the reader with the essence of his talk. The foundation of the European Working Group on CP Stars dates back to autumn 1978 (more precisely and more astronomically: to J. D. 2443793.917) when on the occasion of a workshop on Ap stars in the Infrared, held at the Vienna Observatory, half a dozen Belgian and Austrian astronomers got together and decided that the unsatisfactory situation concerning data cOllecting in Ap research should be removed by Coordinated planning of the observations, especially at ESO, and by more intense exchange of information concerning available, but unpublished data.
References:
Balona, L. A.: 1981, Mon. Not. Roy. Astr. Soc. 196, 159.
Balona, L. A., Stobie, R. S.: 1979a, Mon. Not. Roy. Astr. Soc. 187,217.
Balona, L. A., Stobie, R. S.: 1979b, Mon. Not. Roy. Astr. Soc. 189,649.
Cramer, N., Maeder, A.: 1980, Astron. Astrophys. BB, 135.
Crawtord, D. L.: 1978, Astron. J. 83, 48.
Dziembowski, W.: 1977, Acta Astr. 27,203.
Fleck, R. C., Jr.: 1981, in: 23eme Coll. Intern. d'Astrophysique, Liege,
p.341.
Havnes, 0., Conti, P. S.: 1971, Astron. Astrophys. 14, 1.
Kurtz, D. W.: 1982, Mon. Not. Roy. Astr. Soc. 200, 807.
Maitzen, H. M.: 1982, Astron. Astrophys. 115,275.
Maitzen, H. M., Floquet, M.: 1981, Astron. Astrophys. 100,3.
Maitzen, H. M., Hensberge, H.: 1981, Astron. Astrophys. 96, 151.
Maitzen, H. M., Vogt, N.: 1983, Astron. Astrophys. 123,48.
Maitzen, H. M., Wood, H. J.: 1983, Astron. Astrophys. 126,80.
Michaud, G.: 1970, Astrophys. J. 160,641.
Stritlmatler, P. A., Norris, J.: 1971, Astron. Astrophys. 15,239.
Vogt, N., Faundez, M.: 1979, Astron. Astrophys. Suppt. 36,477.
Weiss, W. W., Schneider, H.: 1983a, The Messenger No. 33, 7.
Weiss, W. W., Schneider, H.: 1983b, Astron. Astrophys., submitted.
Wesselink, A. J.: 1969, Mon. Not. Roy. Astr. Soc. 144,297.

ADS BibCode:
1983Msngr..34...10L
Author(s)/Affiliation(s):
Lauberts, A.; Valentijn, E. A.
AA(European Southern Observatory, Garching, West Germany), AB(European Southern Observatory, Garching, West Germany)
Abstract:
Under a restriction for minimum angular diameter of not less than 1 arcmin, corresponding to the 15th magnitude and allowing morphological classification of structure, 16,000 galaxies have been brought together in the single volume of the ESO/Uppsala catalog (1982). Attention is given to the automatic parameter extraction methods employed, and detailed information is presented for preliminary results on test field No. 358, which covers the Fornax cluster. The data for the 70 galaxies in this test field yield results which are of general interest, such as estimates of total magnitude from a combination of major and minor diameters that yields angular size.

ADS BibCode:
1983Msngr..34...12.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1983Msngr..34...15T
Author(s)/Affiliation(s):
Tarenghi, M.
AA(ESO)
Abstract:
The 2.2 m Zeiss telescope is the last telescope to have arrived on La Silla, thanks to a 25-year loan to ESO from the Max-Planck-Gesellschaft (MPG) who will receive for their contribution 25 %of the observing time. ESO assumed responsibility for the installation of the telescope, the arrangement of necessary modifications, and construction of the building and dome according to specifications agreed with the MPG. ESO will also assume responsibility for the maintenance and operation of the telescope.

ADS BibCode:
1983Msngr..34...16Q
Author(s)/Affiliation(s):
Q-Rieu, N.; Epchtein, N.; Le Bertre, T.
AA(Meudon, Observatoire, Meudon, Hauts-de-Seine, France), AB(Meudon, Observatoire, Meudon, Hauts-de-Seine, France), AC(Meudon, Observatoire, Meudon, Hauts-de-Seine, France)
Abstract:
IR and radio molecular line observations furnish data that are significant not only in the investigtion of circumstellar shell parameters, but in the understanding of circumstellar molecular line excitation. Late-type stars undergo periodic intensity variation in both IR continuum and IR and radio molecular line emission. Molecular species having high dipole moment are very sensitive to radiation. Line shape change, as a function of stellar phase, merely reflects the stellar flux variation. Time-monitoring studies in the IR and mm molecular line emission range is therefore of great importance in the elucidation of circumstellar envelope inner and outer portion interaction via the mass loss phenomenon.
References:
(1) Epchtein N., and Nguyen-Q-Rieu, 1982, Astronomy and Astrophysics
107, 229.
(2) Le Bertre T., Epchtein N., Gispert R., Nguyen-Q-Rieu and Truong-Bach,
Astronomy and Astrophysics, in press.
(3) Caswell J. L., Milne D. K., and Wellington K. J., 1981, M.N.R.AS.
195,89.
(4) Nguyen-Q-Rieu, Laury-Micoulaut C., Winnberg A, and Schultz
G. V., 1979, Astronomy and Astrophysics 75, 351.
(5) Leung C. M., 1975, Astrophysical Journal 199, 340.
(6) Olofsson H., Johansson L. E. B., Hjalmarson A, Nguyen-Quang-Rieu,
1982; Astronomy and Astrophysics 107, 128.

ADS BibCode:
1983Msngr..34...16.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1983Msngr..34...19B
Author(s)/Affiliation(s):
Barwig, H.
AA(Universitäts-Sternwarte München)
Abstract:
Among all kinds of stars probably the most spectacular ones are novae, which suddenly increase their brightness up to more than a million times and then fade again in timescales of months or years to their original faintness. In spite of this outstanding, dramatic behaviour these objects have many properties in common with other so-calied cataclysmic variables (CV). From numerous observational and theoretical work we have learned that these particular stars are very close binaries, some with orbital dimensions of the order of our sun's diameter. The systems consist of a late-type secondary filling its Roche lobe, and a very compact hot primary, which is supposed to be a white dwarf or even a neutron star. Matter flowing from the expanding cooler companion towards the primary normally cannot reach its surface directly due to its excess angular momentum. It is therefore stored first in a rotating accretion disko An important subgroup of the CVs are the dwarf novae which in contrary to novae show quasiperiodic outbursts on a timescale of days with much smaller amplitudes.

ADS BibCode:
1983Msngr..34...20.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1983Msngr..34...21P
Author(s)/Affiliation(s):
Pedersen, H.
AA(European Southern Observatory, Garching, West Germany)
Abstract:
Attention is given to the spectrum of the optical counterpart of the X-ray source 4U1543-47, which was obtained on September 2, 1983 with an Image Dissector Scanner yielding a dispersion of 171 A/mm. The emission line He II 4686 A, and the blend N III 4634, 4631 A, are both clearly visible and allow conclusive identification with the X-ray source. Several interstellar absorption features are present with a relatively large equivalent width, showing that this star is relatively distant.
References:
(1) van Paradijs, J. 1981, The Messenger 23, 1.
(2) Forman, W. et al. 1978, Astrophysical Journal Supplement Series,
38,357.
(3) Blissett, R. J. 1983, lAU Circular No. 3858.
(4) Pedersen, H., Veron, M., Veron, P., and Schuster, H.-E. 1983, IAU
Circular No. 3858.
(5) Oke, J. B., and Greenstein, J. L. 1977, Astrophysical Journal 211,
872.

ADS BibCode:
1983Msngr..34...22V
Author(s)/Affiliation(s):
Véron-Cetty, M.-P.; Véron, P.
AA(ESO) AB(ESO)
Abstract:
The 1.5 m Oanish telescope at La Silla has been used to photograph a number of galaxies with a CCO camera (1) through three different filters: blue (Johnson B), red and infrared (Gunn r (L) and z). The images have been reduced with the ESO image processing system IHAP and then transferred to the VAX computer to use OICOMEO, the high quality hard copy device which produces colour slides. These photographs are in real but not natural colours in the sense that instead of using blue, green and red images, we have used blue, red and infrared. The colour balance is arbitrary but the same for all pictures, except #2. The seeing was 1.2 to 1.5 arcsec. In all cases, north is at the top, east to the left.

ADS BibCode:
1983Msngr..34...24R
Author(s)/Affiliation(s):
Rupprecht, G.; Bues, I.
AA(Remeis-Sternwarte, Bamberg, West Germany), AB(Remeis-Sternwarte, Bamberg, West Germany)
Abstract:
The alleged 'deficit' in cool white dwarf stars of the solar neighborhood is contradicted by the application of a 3/2 reduction factor to the white dwarf numbers presently observed, and the extrapolation of this study's small observed sky area to the total area of the Liebert et al (1979) study. Slightly more cool dwarfs are found than had been predicted by theory. This result is noted to require future spectroscopic checks of the photometric identification procedure, as well as a better statistical basis for the identification success ratio. A further result is the substantial increase in the number of observations of southern GD stars.

ADS BibCode:
1983Msngr..34...26A
Author(s)/Affiliation(s):
Andersen, J.; Gustafsson, B.; Lambert, D. L.
AA(Universitetets Astronomiske Observatorium, Copenhagen, Denmark), AB(Astronomiska Observatoriet, uppsala, Sweden), AC(Texas, University, Austin, TX)
Abstract:
The ESO's CoudeEchelle Spectrometer is presently used in investigtions of the mechanisms by which Li is produced in stars and the connection between atmospheric Li abundance and the degree of mixing in the stellar envelope. Determinations are made by measurements of the Li-6/Li-7 isotopic abundance ratio, and of the Li abundance in such evolved stars as those with weak G-bands, whose chemical composition suggests that their atmospheres are mixed with large amounts of CNO-processed interior materials. The present observations have nearly doubled the number of weak G-band stars with Li, enlarging the observational bases for attempts to understand the conditions under which these stars preserve or produce Li.

ADS BibCode:
1983Msngr..34...28B
Author(s)/Affiliation(s):
Baade, D.
AA(ESO)
Abstract:
Two well-attended IAU symposia in 1975 and 1981 (in the respective proceedings the interested reader may find all relevant references) and an IAU colloquium being planned for the mid-eighties, all three devoted exclusively to Be and shell stars, show that stellar astronomers take a very active interest in these strange objects. The first Be star, y Cas, was identified as such by Secchi as early as 1866, and today 2- 3% of all stars in the Bright Star Catalogue are known to belong to this class. The amount of observational data that has been accumulated is therefore vast, and at all times it has been of the best technical quality. For this reason we are now at a stage where for more and more of these stars it becomes possible (or tempting) to search for periodicities in the (sometimes spectacular) spectroscopic variability exhibited on time seales of years by many Be stars. The idea is that these stars might be binaries and that the mass exchange between the two components is the origin of the line emitting shell around the B-type primary. But for many objects it may weil take a few more decades to distinguish with some certainty between true and spurious periods. So far, there is no indication that the binary frequency of Be stars is any higher than the one of "normal" B stars which itself is roughly the same as for 0 through G type stars.

ADS BibCode:
1983Msngr..34...28.
Author(s)/Affiliation(s):
ESO
AA(ESO)

ADS BibCode:
1983Msngr..34...30H
Author(s)/Affiliation(s):
Holweger, H.
AA(Kiel, Neue Universitaet, Institut fuer Theoretische Physik und Sternwarte, Kiel, West Germany)
Abstract:
The ESO's Coude Echelle Spectrometer is used to obtain spectra of sufficiently high resolution to yield true stellar line profiles, for the case of the Ba stars that make up at least 1 percent of all red giants. An attempt is made to determine the mechanism by which unorthodox mixing events and neutron releases occur in the lower red giant branch. Data are obtained which suggest an entire sequence of combined neutron irradiation and mixing processes, although the standard stellar evolution theory does not predict heavy element production at the relatively high effective temperatures and low luminosities of the objects presently studied.

ADS BibCode:
1983Msngr..34...33K
Author(s)/Affiliation(s):
Kubiak, M.
AA(Obserwatorium Astronomiczne, Warsaw, Poland; Observatorium Hoher List, Daun, West Germany)
Abstract:
The optical pulsar H2252-035 has been observed with a standard UBV photometer at La Silla Observatory, using an integration time of 5 sec in each bandpass. Attention is given to the results of a periodogram analysis of the data in which amplitudes are given in intensity units. These data, after subtraction of the short period modulations, were folded with the orbital period to yield average light and color curves. It appears that the site at which the original radiation is being reprocesed is located far enough from the disk so that both illuminating and reprocessed radiations can travel to and from it relatively undisturbed. The stability of the 859- and 805-sec periods is noted.

ADS BibCode:
1983Msngr..34...35B
Author(s)/Affiliation(s):
Biereichel, B.; Gustafsson, B.; Raffi, G.
AA(ESO) AB(ESO) AC(ESO)
Abstract:
New instrumental control and acquisition software has been developed for the on-line minicomputers on La Silla. This has been done to allow easy portability of programmes between the various installations, to shorten the development time for new programmes, to ease software maintenance problems, and to provide the observer with a common, high-level interface to the various instruments.

ADS BibCode:
1983Msngr..34...38G
Author(s)/Affiliation(s):
Gillet, D.; Bouchet, P.; Maurice, E.
AA(European Southern Observatory, Garching, West Germany), AB(European Southern Observatory, Garching, West Germany), AC(European Southern Observatory, Garching, West Germany)
Abstract:
Pulsating stars, which constitute an important group of variables, exhibit in their spectra a large number of intensity, shape, and emission variations that can be observed with modern high resolution spectrographs and which, being a consequence of the dynamic state of the stars' pulsating atmospheres, can reveal fundamental processes. After briefly assessing the pertinent emission line observations and their interpretation in terms of stellar atmosphere shock wave propagation, attention is given to the H-alpha emission of Mira Ceti, which is the brightest Mira star in the sky. It is shown that the emission profile intensity can be very different for each period.
References:
Baird, S. R., 1982, P.A.S.P. 94, 850.
Breger, M., 1979, P.A.S.P. 91, 5.
Dravins, 0., Lind, J., Särg, K., 1977, Astronomy and Astrophysics
54,381 (c).
Dürbeck, H. W., Seitter, W. C., 1982, Landolt-Börnstein, 2, p. 197, ed.
K. Schaiters and H. H. Voigt, Springer-Verlag.
Goldberg, B. A., Walker, G. A. H., 1974, Astronomy and Astrophysics
32,355.
Havlen, R. J., 1970, ESO Annual Report (d).
Hutchinson, J. L., Hili, S. J., Lillie, C. F., 1975, Astronomical Journal
80, 1044.
LeContel, J.-M., Morel, P.-J., 1982, Astronomy and Astrophysics
107, 406 (b).
Preston, G. W., 1962, Astrophysical Journal 136, 866 (a).
Preston, G. W., Paczynski, B., 1964,AstrophysicalJournal140, 181 (f).
Wallerstein, G., 1959, Astrophysical Journal 130, 560 (e).

ADS BibCode:
1983Msngr..34...41B
Author(s)/Affiliation(s):
Bauersachs, W.
AA(ESO)
Abstract:
In the beginning of July 1983, an unusual snowstorm somewhat perturbed the life on La Silla. Here are the records: Thursday, July 7, 1983: bad weather with symptoms of a development to the worse. Friday, July 8, 1983: snow-storm, power-faifure, evacuation of the mountain, 30 trapped. Saturday, July 9, 1983: storm continues until midnight. Sunday, July 10, 1983: bright weather, snow-sweeping, repairs. Monday, July 11, 1983: half of the crew returns, preparations of equipment. Tuesday, July 12, 1983: return to full work.

ADS BibCode:
1983Msngr..34...43.
Author(s)/Affiliation(s):
ESO
AA(ESO)
Abstract:
EI telescopio de 2,2 m se encuentra Listo