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Schmitz, M.

Publications and source records attributed to Schmitz, M..

Accurate Positions for MCG Galaxies

We have measured accurate celestial coordinates for 4741 extragalactic objects, primarily drawn from a list of MCG galaxies with no recently published accurate positions.

MCG↗

NED and SIMBAD Conventions for Bibliographic Reference Coding

The primary purpose of the 'reference code' is to provide a unique and traceable representation of a bibliographic reference within the structure of each database. The code is used frequently in the interfaces as a succinct abbreviation of a full bibliographic reference. Since its inception, it has become a standard code not only for NED and SIMBAD, but also for other bibliographic services.

NED SIMBAD bibliographic reference coding astronom↗

Proton-induced fragmentation of carbon at energies below 100 MeV

Radiation effects caused by single cosmic ray particles have been studied for many years in radiobiological experiments for different biological objects and biological end-points. Additionally, single event effects in microelectronic devices have gained large interest. There are two fundamental mechanisms by which a single particle can cause radiation effects. On the one hand, a cosmic ray ion with high linear energy transfer can deposit a high dose along its path. On the other hand, in a nuclear collision, a high dose can be deposited by short range particles emitted from the target nucleus. In low earth orbits a large contribution to target fragmentation events originates from trapped protons which are encountered in the South Atlantic Anomaly. These protons have energies up to a few hundred MeV. We study the fragmentation of C, O and Si nuclei - the target nuclei of biological material and microelectronic devices - in nuclear collisions. Our aim is to measure production cross sections, energy spectra, emission directions and charge correlations of the emitted fragments. The present knowledge concerning these data is rather poor. M. Alurralde et al. have calculated cross sections and average energies of fragments produced from Si using the cascade-evaporation model. D.M. Ngo et al. have used the semiempirical cross section formula of Silberberg and Tsao to calculate fragment yields and the statistical model of Goldhaber to describe the reaction kinematics. Cross sections used in these models have uncertainties within a factor of two. Our data will help to test and improve existing models especially for energies below 300 MeV/nucleon. Charge correlations of fragments emitted in the same interaction are of particular importance, since high doses can be deposited if more than one heavy fragment with a short range is produced.

Schmitz, M.↗

Revised sizes and positions for the Mailyan dwarf galaxy catalog

New positions (good to +/- 15 arcsec), revised sizes, and sample cross-identifications are presented for dwarf galaxies discovered and published by Mailyan (1973, Astrofizika, 9, 33). Of the 104 originally cataloged galaxies we were able to recover only 100, despite an extensive search of the red and blue Palomar Observatory Sky Survey (POSS) prints. Over half of the recovered objects were found to correspond to previously cataloged galaxies; few if any of these are dwarf spheriodal galaxies, but rather mostly dwarf irregulars of low surface brightness.

Madore, B. F.↗

Far infrared supplement: Catalog of infrared observations

The Far Infrared Supplement: catalog of infrared observations summarizes all infrared astronomical observations at far infrared wavelengths published in the scientific literature between 1965 and 1982. The Supplement list contains 25% of the observations in the full catalog of infrared observations (C10), and essentially eliminates most visible stars from the listings. The Supplement is more compact than the main Catalog (it does not contain the bibliography and position index of the C10), and is intended for easy reference during astronomical observations.

Gezari, D. Y.↗

Catalog of infrared observations including: Bibliography of infrared astronomy and index of infrared source positions

The Catalog of Infrared Observations and its Far Infrared Supplement summarize all infrared astronomical observations at infrared wavelengths published in the scientific literature between 1965 and 1982. The Catalog includes as appendices the Bibliography of infrared astronomy which keys observations in the Catalog with the original journal references, and the index of infrared source positions which gives source positions for alphabetically listed sources in the Catalog. The Catalog data base contains over 85,000 observations of about 10,000 infrared sources, of which about 2,000 have no known visible counterpart.

Gezari, D. Y.↗

Ultraviolet observations of the transient X-ray sources A0535 + 26 and A0620-00

Observations of A0535+26 (HDE 245770) by the ANS in September 1975 and March 1976 when it was at the X-ray low state are discussed. Also observed were 58 early-type stars lying within 10 deg of HDE 245770; these stars are used to derive a localized extinction curve. On the basis of the depth of the 2200 A interstellar absorption feature observed in the ANS flux distribution of HDE 245770 and the shape of the localized extinction curve, an E(B-V) = 0.72 is derived for HDE 245770. Observations were made of this system during its X-ray flare-up (October 1980) and quiescent (November 1981) states by the IUE. It is noted that the fine error sensor on board the IUE detected an increase in the optical brightness of HDE 245770 during the X-ray outburst. This greatly corroborates the identification of HDE 245770 as the optical counterpart of A0535+26. No significant change in the absorption-line profiles during the X-ray high and low periods is found, indicating that there was no significant increase in the stellar wind density when the X-ray flare-up occurred. The UV continuum level increased by less than 6 percent when it was near peak X-ray luminosity. The UV spectrum of HDE 245770 suggests that it is a B0 V or a B0 III star with its dereddened continuum slope slightly in favor of being a giant.

Wu, C.-C.↗

Far infrared supplement: Catalog of infrared observations

The development of a new generation of orbital, airborne and ground-based infrared astronomical observatory facilities, including the infrared astronomical satellite (IRAS), the cosmic background explorer (COBE), the NASA Kuiper airborne observatory, and the NASA infrared telescope facility, intensified the need for a comprehensive, machine-readable data base and catalog of current infrared astronomical observations. The Infrared Astronomical Data Base and its principal data product, this catalog, comprise a machine-readable library of infrared (1 micrometer to 1000 micrometers) astronomical observations published in the scientific literature since 1965.

Gezari, D. Y.↗

Catalog of infrared observations

The infrared astronomical data base and its principal data product, the catalog of Infrared Observations (CIO), comprise a machine readable library of infrared (1 microns to 1000 microns astronomical observations. To date, over 1300 journal articles and 10 major survey catalogs are included in this data base, which contains about 55,000 individual observations of about 10,000 different infrared sources. Of these, some 8,000 sources are identifiable with visible objects, and about 2,000 do not have known visible counterparts.

Gezari, D. Y.↗

Infrared astronomical data base and catalog of infrared observations

A computer data base of infrared astronomical observations has been established at NASA/Goddard Space Flight Center. It contains a summary of all infrared (1-100 microns) observations of celestial sources outside the solar system, published in the major scientific journals since 1960, as well as the contents of infrared surveys and catalogs. A Catalog of Infrared Observations (CIO) has been developed from the data base in printed and magnetic tape versions. A bibliographic Guide to the Infrared Astronomical Literature, and an Altas of Infrared Source Names and Positions will be published in conjunction with the catalog. Future plans include development of an interactive data system at Goddard which will give a user direct access to the computerized data.

Schmitz, M.↗

Infrared astronomical data base and catalog of infrared observations

The NASA/Goddard Space Flight Center has developed a computer data base of infrared astronomical observations. The data base represents a machine-readable library of infrared observational data published in the relevant literature since 1960 for celestial sources outside the solar system. It likewise includes the contents of infrared surveys and catalogs. A catalog of infrared observations has been developed in both printed and magnetic-tape formats. The data base will be accessed through a bibliographic guide and an atlas of infrared source names and positions. Future plans also include two-dimensional graphical displays of infrared data and a user-interactive data terminal.

Schmitz, M.↗

Merged infrared catalogue

A compilation of equatorial coordinates, spectral types, magnitudes, and fluxes from five catalogues of infrared observations is presented. This first edition of the Merged Infrared Catalogue contains 11,201 oservations from the Two-Micron Sky Survey, Observations of Infrared Radiation from Cool Stars, the Air Force Geophysics Laboratory four Color Infrared Sky Survey and its Supplemental Catalog, and from Catalog of 10 micron Celestial Objects (HALL). This compilation is a by-product of a computerized infrared data base under development at Goddard Space Flight Center; the objective is to maintain a complete and current record of all infrared observations from 1 micron m to 1000 micron m of nonsolar system objects. These observations are being placed into a standardized system.

Schmitz, M.↗