= The upper layers of the atmospheres of late-ype stars is investigated. The study is based on the observation and analysis of carbon monoxide (CO) fundamental (delta v 1) spectra at 4.7 microns. CO fundamental spectra provide an alternative way for the study of cool stellar atmospheres. A postdispersion system for astronomical Fourier spectrometers is developed. This is achieved in the constructed instrument by using a liquid helium-cooled grating monochromator as a narrowband filter. The theoretical basis for the quantitative evaluation of observed CO spectra in a number of cool stars is provided. Boundary temperatures and thermal profiles of stellar atmospheres were determined from the observation of a number of stars and semi-empirical models derived. The comparison of the observed temperatures with theoretical predictions based on radiative equilibrium (RE) models yields good agreement for several cool stars including Arcturus and Aldebaran. The CO models are incompatible with homogeneous chromospheres (hot, non-classical regions), as derived for some of the stars from conventional diagnostics by other groups. A second group of stars (epsilon Vir, beta Draco, beta Corvi, beta Gem) shows boundary temperatures considerably higher than predicted from RE-models. A strong discrepancy between CO-based and chromospheric model is still obvious in beta Gem, but cannot be claimed for beta Draco. " Annual Report, 1988 H. vanderLaan 1988 116 P The European Southern Observatory annual report, 1988, is presented. The research papers are focused on the following subjects: the European coordination facility for the space telescope, the research with Chilean institutes, image processing, and sky survey. The considered equipment and instrument facilities are: telescopes, optical and infrared instrumentation, seeing improvement, computer equipment, and high resolution imaging and interferometry. Financial and organizational matters are discussed. The use of telescopes, the study programs, the publications, the 1989 council and committee members are listed. extragalactic sources, the statistical evolution of the observed population of sources, and the cosmological model is discussed. Three simple forms of statistical evolution: pure luminosity evolution (PLE), pure density evolution (PDE), and generalized luminosity evolution (GLE), are considered in detail together with what these forms imply about the physical evolution of individual sources. Two methods are used to analyze the statistical evolution of the observed distribution of QSO's (quasars) from combined flux limited samples. It is shown that both PLE and PDE are inconsistent with the data over the redshift range 0 less than z less than 2.2, and that a more complicated form of evolution such as GLE is required, independent of the cosmological model. This result is important for physical models of AGN, and in particular, for the accretion disk model which recent results show may be inconsistent with PLE. Author N89-29284 Max-Planck-Inst. fuer Physik und Astrophysik, (MPE-Preprint-145; ETN-89-95340) Copyright Avail: Eggenstein-Leopoldshafen 2, Fed. Republic of Germany The theory of the formation and evolution of X-ray binaries and binary or low-magnetic-field radio pulsars is discussed. The simple semi-analytical description is emphasized. Massive X-ray binaries, low-mass X-ray binaries, and X-ray binaries in globular clusters, as well as the transformation of some of these into millisecond radio pulsars, are studied. ESA N89-29285 Max-Planck-Inst. fuer Physik und Astrophysik, Garching (Germany, F.R.). Inst. fuer Extraterrestrische Physik. EVOLUTION OF WIDE BINARY MILLISECOND PULSARS IN GLOBULAR CLUSTERS S. Rappaport (Massachusetts Inst. of Tech., Cambridge.), A. Putney, and Frank Verbunt Apr. 1989 37 p Submitted for publication (MPE-Preprint-148; ETN-89-95342) Copyright Avail: Fachinformationszentrum Karlsruhe, 7514 Eggenstein-Leopoldshafen 2, Fed. Republic of Germany The evolution of wide binary millisecond radio pulsars, in a globular cluster environment, is investigated. Through an extensive series of numerical scattering experiments, the study of encounters between a binary radio pulsar (consisting of a neutron star and a low-mass degenerate companion) and passing cluster field stars is effectuated. Initial binary orbital periods from 3 to 1000 days are considered. Globular cluster star densities and distributions of stellar masses and velocities are taken from two models to represent moderately condensed (omega Cen) and highly condensed (47 Tuc) cluster cores. The scattering cross sections are derived for three scattering processes which can liberate the neutron star, including exchange and ionization reactions as well as direct collisions between stars. They are computed for inducing orbital eccentricities into binary radio pulsars with initially circular orbits and applied to the known pulsars in globular clusters. The measured orbital eccentricity of the PSR 1620-26 system in M4 is only marginally consistent with its spin-down age, and that the PSR 0021-72B system in 47 Tuc is expected to have a significant eccentricity (approximately higher than 0.1) if its orbital period is near the upper end of its presently allowed period range and its age exceeds 10 to the 9th power years; and that the single millisecond pulsar PSR 2127+12 in M15 may be liberated from a wide binary via an encounter with a cluster star, whereas such a process is not likely to have produced the single millisecond pulsar PSR 1821-24 in M28. The calculations made for wide binary millisecond radio pulsars, have implications for other wide binaries in globular clusters. ESA N89-29286 Max-Planck-Inst. fuer Physik und Astrophysik, Garching (Germany, F.R.). Inst. fuer Extraterrestrische Physik. EVIDENCE FOR TWO CHARGED PARTICLE POPULATIONS IN THE CRAB NEBULA Thomas Bork Mar. 1989 7 p Submitted for publication (MPE-Preprint-147; ETN-89-95341) Copyright Avail: Fachinformationszentrum Karlsruhe, 7514 Eggennstein-Leopoldshafen 2, Fed. Republic of Germany A comparison between the measured soft X-ray brightness distribution of the Crab nebula and simulated data is made, in order to understand the conversion of the Crab pulsar's rotational energy into synchrotron radiation. Data is obtained from the High Resolution Imager on board the Einstein observatory. A 3-D model based on Rees and Gunn, and Aschenbach and Brinkmann theories is applied. The model suggests a torus shaped emission region. The analysis shows that this region, when viewed from the earth, has an angular extent of 0.24 radians and ellipticity of 5.5. Data from radio, optical, soft- and hard X-ray frequencies allowed to infer the existence of two spatially separated charged particle ESA populations in the Crab pulsar environment. N89-29287 Max-Planck-Inst. fuer Physik und Astrophysik, Garching (Germany, F.R.). Inst. fuer Extraterrestrische Physik. TOWARDS A THEORY OF STAR FORMATION Hans Zinnecker Apr. 1989 18 p Submitted for publication (MPE-Preprint-150; ETN-89-95344) Avail: Fachinformationszentrum Karlsruhe, 7514 Eggenstein-Leopoldshafen 2, Fed. Republic of Germany Some key elements towards a theory of star formation are discussed. Local and global star formation processes are included. The role of molecules and dust as well as spatial and temporal variations of the initial conditions are emphasized. Globally, the energy input from massive stars seems to regulate gas-rich galactic systems. Massive stars can cause negative or positive feedback on star formation, leading to a steady star formation rate or molecular cloud scale, starbursts, respectively. On the fragmentation is influenced by the effects of the tidal field and the magnetic field inside the clouds, with the possibility of a spatial segregation of high mass and low mass bound fragments. Locally, starbursts, respectively. On the molecular cloud scale, fragmentation is influenced by the effects of the tidal field and protostellar fragments where magnetic support breaks down. When collapse is triggered by an increase in external pressure or by radiative implosion, magnetic support is less effective and a larger fraction of the mass of each fragment will end up as stellar mass. The relation between fragment mass and stellar mass determines the slope of the Initial Mass Function that is derived from the fragment mass spectrum. For triggered star formation this relation should differ from that for spontaneous star formation which may explain why the slope of the Initial Mass Function in starburst systems is flatter than in the solar neighborhood. ESA N89-29288 Max-Planck-Inst. fuer Physik und Astrophysik, Garching (Germany, F.R.). Inst. fuer Extraterrestrische Physik. MEASUREMENT OF THE VELA PULSAR'S PROPER MOTION AND DETECTION OF THE OPTICAL COUNTERPART OF ITS COMPACT X-RAY NEBULA Hakki Oegelman, Lydie Koch-Miramond, and Michel Auriere (Observatoire du Pic-du-Midi, Bagneres de Bigorre, France) Apr. 1989 18 p Submitted for publication (Contract DFG-Mo-416/3-3) (MPE-Preprint-151; ETN-89-95345) Copyright Avail: Fachinformationszentrum Karlsruhe, 7514 Eggenstein-Leopoldshafen 2, Fed. Republic of Germany = The results of optical astrometry and photometry in the Vela pulsar field are reported. The proper motion of the pulsar and the optical counterpart of the approximately 2 minutes diameter compact nebula seen in X-rays, are investigated. The relative position measurements are fitted with previous published data yield of mu (alfa) -0.026 (+ or -) 0.006 (1 sigma) seconds/year and mu (delta) = 0.028 (+ or -) 0.006 (1 sigma) seconds/year as the proper motion of the pulsar. The implied transverse velocity of the pulsar at an assumed distance of 500 parsec is approximately 90 (+ or -) 15 km/s, in the northwest direction. After a star detection algorithm is used to detect and subtract the stellar contribution, a diffuse nebula centered around the pulsar is clearly distinguishable in the V and B band exposures; several whisp-like structures can be recognized in the images. The optical size of the compact nebula, 2 to 6 x 10(17) cm, is comparable to that in X-rays, and the optical intensity can be connected to the X-ray points by a power-law type emission with photon number index gamma approximately 2. With this spectrum, the total luminosity of the compact nebula extending from optical to X-rays is about 10(33) power erg/s. Possible origins of this compact nebula are discussed. ESA N89-29289# Tata Inst. of Fundamental Research, Bombay (India). IMPLICATIONS OF THE CORRELATION BETWEEN THE T. N. Rengarajan and K. V. K. Iyengar 1989 15 p The correlation observed between the radio continuum and the far-infrared (far-IR) luminosities for spiral galaxies was extended to lower frequency by using the 408 MHz data of Harnett (1982). The correlation was also studied as a function of radio spectral index between 2.8 cm and 6.3 cm and was found to be independent of it. The tighter correlation between the radio and the far-IR luminosities as compared to those between the blue and the radio, the blue and the far-IR, is evidence that the electrons responsible for the radio emission mostly originate in young massive stars. The dispersion observed for the far-IR radio correlation was used to set limits on the variation of several parameters like the star formation rate, the slope of the initial mass function, the relative frequency of supernovae of type I and type II, the frequency of supernovae as a function of the morphological type of the galaxy, the magnetic field in the galaxies, and the residence time of energetic electrons. Author N89-29290# Geneva Observatory (Switzerland). Swiss National Foundation for Scientific Research The coravel radial velocity observations of 62 red giant stars in five Hyades-like open clusters (NGC 2447, 2539, 2632, 6633 and 6940) are analyzed for membership determination and binary detection. Fourteen spectroscopic binaries are discovered and four more are suspected, (a binary percentage equal to 25 to 30 percent). Twelve orbits are determined, including one for KW 428 in Praesepe, and two triple systems identified. At least nine of the ten stars found in the Hertz-sprung gap are composite binaries of the (gK+dA) type. Seven nonmember stars are detected. The radial velocity dispersion is close to the value expected from the virial theorem. The composite color magnitude diagram of the 55 members shows a very clean isochronous curve: the clump loop and the asymptotic branch are well defined. All bright giants appear to be in the latter phase. A second concentration of red giants RED GIANTS IN OPEN CLUSTERS. 2: ORBITS OF TEN SPECTROSCOPIC BINARIES IN NGC 2360, 2437, 2447, 5822, 5823, 6475 J.-C. Mermelliod, M. Mayor, J. Anderson, B. Nordstrom, H. Lindgren, and A. Duquennoy 1989 14 P Submitted for publication Sponsored by the European Southern Observatory, the Danish Board for Astronomical Research and the Swiss National Fund for Scientific Research (Ser-C-Prepubl-Fasc-38-Pt-2; ETN-89-95177) Avail: NTIS HC A03/MF A01 The results of a systematic program to detect spectroscopic binaries in open clusters and determine their orbits are given, based on radial velocity observations made with the CORAVEL scanners in both hemispheres. Orbits for ten (single-lined) spectroscopic binaries in six southern clusters (NGC 2360, 2437, 2447, 5822, 5823, and 6475) are presented. The orbital periods range from 65 to 1370 days, and the velocity semi-amplitudes from 4.4 km/s to 26.0 km/s. All the binaries are confirmed cluster members except that in NGC 5823. The star NGC 2360-0051 has an eccentric despite its 98-day period. NGC 6475-0134 has a circular orbit with a 217-day period. For cluster giants, the cutoff period for eccentric orbits decreases with age. 91 LUNAR AND PLANETARY EXPLORATION ESA Includes planetology; and manned and unmanned flights. For spacecraft design or space stations see 18 Spacecraft Design, Testing and Performance. N89-29292*# Martin Marietta Aerospace, Denver, CO. Planetary Science Branch. STUDY OF SAMPLING SYSTEMS FOR COMETS AND MARS Final Report 196 p R. J. Amundsen and B. C. Clark Mar. 1987 (Contract NAS9-17511) (NASA-CR-185514; NAS 1.26:185514; MCR-86-654) Avail: NTIS HC A09/MF A01 CSCL 03B Several aspects of the techniques that can be applied to acquisition and preservation of samples from Mars and a cometary nucleus were examined. Scientific approaches to sampling, grounded in proven engineering methods are the key to achieving the maximum science value from the sample return mission. If development of these approaches for collecting and preserving does not preceed mission definition, it is likely that only suboptimal techniques will be available because of the constraints of formal schedule timelines and the normal pressure to select only the most conservative and least sophisticated approaches when development has lagged the mission milestones. With a reasonable investment now, before the final mission definition, the sampling approach can become highly developed, ready for implementation, and mature enough to help set the requirements for the mission hardware and its performance. Author N89-28532# Joint Publications Research Service, Arlington, VA. METHOD FOR RESEARCH ON PLANET VENUS USING FLOATING BALLOON STATIONS: MATHEMATICAL MODEL V. A. Vorontsov, V. A. Deryugin, V. P. Karyagin, R. S. Kremnev, V. V. Kuznetsov, V. M. Linkin, K. M. Pichkhadze, G. N. Rogovskiy, and A. V. Terterashvili In its JPRS Report: Science and Technology. USSR Report: Life Sciences 15 Mar. 1989 p 49-50 Transl. into ENGLISH from Kosmicheskiye Issledovaniya (Moscow, USSR), v. 26 no. 3, May-Jun. 1988 p 430-433 (For primary document see N89-28527 23-12) Avail: NTIS HC A05/MF A01 92 SOLAR PHYSICS Includes solar activity, solar flares, solar radiation and sunspots. For related information see 93 Space Radiation. N89-29293 Institut d'Aeronomie Spatiale de Belgique, Brussels. SOLAR ULTRAVIOLET RADIATION WITHIN THE MIDDLE ATMOSPHERE Paul C. Simon and Didier Gillotay 1989 20 P Presented at the International Radiation Symposium, Lille, France, 18-24 Aug. 1988 Submitted for publication (Aeronomica-Acta-A-337-1989; ISSN-0065-3713; ETN-89-95187) Avail: Institut d'Aeronomie Spatiale de Belgique, 3 Avenue Circulaire, B-1180 Brussels, Belgium The analysis of the observations of solar ultraviolet irradiance, above Lyman alfa wevelength during phase of solar cycle 21, is performed. Important discrepancies (up to 40 percent) between the observations are present below 200 nm. Above this wavelength the agreement between the two space shuttle observations is good. Ultraviolet irradiance values with accuracies between 3.5 and 5.2 per cent are obtained. Variabilities related to the 27-day rotation period and the 11-year cycle are revised on the basis of the recent analysis of the solar backscatter ultraviolet and solar mesophere explorer observations. ESA N89-29294 Institut d'Aeronomie Spatiale de Belgique, Brussels. Marcel Nicolet 1989 90 p Submitted for publication The representative observations of the recent solar spectral irradiance measurements are reported. The observations are performed by means of satellites, rockets and balloons, in addition to ground level and aircraft measurements. It is shown that simultaneous and continuous measurements are needed to reduce the systematic differences between the various observed spectral irradiances. It is important to reduce the multiple random errors in order to permit meaningful studies of the variability of the solar fluxes. Permanent support by space agencies is required for the acquisition of a reliable data base of accurate spectral solar irradiances. ESA N89-29295# European Space Agency, Paris (France). R. Reinhard, comp. and B. Battrick, comp. Nov. 1988 118 p The planning includes 24 projects involving a total of 36 spacecraft. A summary of the scientific objectives, the payload, the key spacecraft and mission/orbit of each project are presented together with a drawing of the spacecraft and a plot of the orbit. ESA Alan J. Kogut Apr. 1989 195 p (Contract DE-AC03-76SF-00098) (DE89-014895; LBL-27233) Avail: NTIS HC A09/MF A01 Three experiments measured the intensity of the Cosmic Microwave Background (CMB) at wavelengths 4.0, 3.0, and 0.21 cm. The measurement at 4.0 cm used a direct-gain total-power radiometer to measure the difference in power between the zenith sky and a large cryogenic reference target. Foreground signals are measured with the same instrument and subtracted from the zenith signal, leaving the CMB as the residual. The reference target consists of a large open-mouth cryostat with a microwave absorber submerged in liquid helium; thin windows block the radiative heat load and prevent condensation atmospheric gases within the cryostat. The thermodynamic temperature of the CMB at 4.0 cm is 2.59+ or 0.07 K. The measurement at 3.0 cm used a superheterodyne Dicke-switched radiometer with a similar reference target to measure the zenith sky temperature. A rotating mirror allowed one of the antenna beams to be redirected to a series of zenith angles, permitting automated atmospheric measurements without moving the radiometer. A weighted average of 5 years of data provided the thermodynamic temperature of the CMB at 3.0 cm of 2.62 + or 0.06 K. The measurement at 0.21 cm used Very Large Array observations of interstellar ortho-formaldehyde to determine the CMB intensity in molecular clouds toward the giant HII region W51A (G49.5-0.4). Solutions of the radiative transfer problem in the context of a large velocity gradient model provided estimates of the CMB temperature within the foreground clouds. Collisional excitation from neutral hydrogen molecules within the clouds limited the precision of the result. The thermodynamic temperature of the CMB at 0.21 cm is 3.2 + or - 0.9 K. DOE N89-29297# Ballistic Research Labs., Aberdeen Proving Ground, QUANTIZATION BY COSMIC BACKGROUND RADIATION (AD-A208103; BRL-TR-2991) Avail: NTIS HC A03/MF A01 It is suggested that various modes in the cosmic background radiation field may account for the discrete properties exhibited by small systems. In particular, this view is applied to the 1, 2-, and 3-D oscillators and the hydrogen atom, systems which were treated by Schrodinger in his first papers on quantum mechanics. The usual energy formulas for the above systems are derived using this point of view, together with some indication of how transition probabilities might also be calculated. A connection between de Broglie's associated wave and a free mass moving in the cosmic background is also discussed. Analogs of the uncertainty and correspondence principles are briefly mentioned as are some of the implications this view might have for interpreting quantum theory. In this view particles and waves are separate, interacting entities and not complementary aspects of the same thing. GRA N89-29298* Max-Planck-Inst. fuer Physik und Astrophysik, (Grants NAG8-571; NAG8-674; NSG-7643; NATO-RG-331/88) It is shown that the number of millisecond radio pulsars, in globular clusters, should be larger than 100, applying the standard scenario that all the pulsars descend from low-mass X-ray binaries. Moreover, most of the pulsars are located in a small number of clusters. The prediction that Teran 5 and Liller 1 contain at least about a dozen millisecond radio pulsars each is made. The observations of millisecond radio pulsars in globular clusters to N89-29299# Office National d'Etudes et de Recherches LA RECHERCHE AEROSPATIALE, BIMONTHLY BULLETIN, The model of a parallel shared memory computer and two classes of parallel multi-instruction multiple-data machines; the laminar stability theory applied to two-dimensional boundary layers in compressible flow over an adiabatic wall; an implicit finite-volume method for solving the two-dimensional and three-dimensional time-dependent Navier-Stokes equations; the applications of infrared absorption spectrometry by diode laser to the analysis of gases of combustion; and the aerodynamic visualization for ESA impulsively started airfoils are discussed. N89-29300# Office National d'Etudes et de Recherches Aerospatiales, Paris (France). LA RECHERCHE AEROSPATIALE, BIMONTHLY BULLETIN, NUMBER 1988-5 ESA Jun. 1989 62 p Transl. into ENGLISH of La Recherche Aerospatiale, Bulletin Bimestriel (Paris, France), no. 1988-5, 1988 (ESA-TT-1162; ETN-89-95392) Avail: NTIS HC A04/MF A01 The use of electromagnetic waves in the fabrication of composite materials; the optimization of the inputs and outputs of a secondary memory in multiprocessor architecture; the model of nonlinear combustion instability with nonlinear pressure coupling in solid propellant rocket motors; the tension-torsion testing machine operating at high temperature (1000 C); and the possibilities of millimetric waves for local, contactless measurement of temperature and humidity are discussed. ESA N89-29301# Office National d'Etudes et de Recherches LA RECHERCHE AEROSPATIALE, BIMONTHLY BULLETIN, ESA Jun. 1989 55 p Transl. into ENGLISH of La Recherche Aerospatiale, Bulletin Bimestriel (Paris, France), no. 1988-6, 1988 (ESA-TT-1165; ETN-89-95393) Avail: NTIS HC A04/MF A01 Topics discussed include: (1) the solution of Euler equations, applied to supersonic flows, using a finite element method; (2) the language designed to provide a synthetic specification of the architecture/algorithm/mapping system; (3) the concept of the chemical laser emission in the visible range; (4) the generalization of the Roe scheme for computing flows by solution of the Euler equations, in the case of a mixture of inviscid gases with variable concentrations; and (5) the numerical simulation of an incompressible two-dimensional mixing layer at high Reynolds number, using a finite-difference method. ESA N89-29302# European Space Agency, Paris (France). [ACTIVITIES REPORT OF ESA] Annual Report, 1988 Norman Longdon, ed. and James Hunt, ed. 1989 222 p Original contains color illustrations (ISSN-0258-025X; ETN-89-94989) Copyright Avail: NTIS HC A10/MF A01 The described activities include, scientific programs, Earth observation program, microgravity program, telecommunications program, space transportation systems, space stations and platforms, technological research and development, scientific research, satellite operations, data handling and archiving, ground facilities for space systems, and technical infrastructure. ESA 3379 |