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At least 109 records · Page 6

A Far Infrared Sky Survey

Balloon-borne instrumentation for detection of far IR extended emission regions and bright point sources, describing results of initial flights

Frederick, C. L.↗

The list of the stars from the Two-micron sky survey: A preliminary catalog by G. N. Neugebauer et al (IRC), the identification of which is not correct

Two tables are published. The first presents the numbers of stars according to the Catalog IRC for which all or part of the identification with the Catalogs BS-HR, GC or DM is incorrect. The second table presents the numbers of stars in the IRC catalog, for which the identifications with variable stars printed with them are erroneous, whereas other identifications are usually correct.

Kukarkin, B. V.↗

A 1.2 meter balloon-borne telescope for a submillimeter wave sky survey

A balloon-borne, 1.2 meter Cassegrain telescope designed for diffraction-limited imagery at 100 microns is being developed for a survey of the Galactic plane at submillimeter wavelengths. The telescope pointing system is servocontrolled using a gyroscope for the primary stabilization reference. Extensive use is made of microprocessors for flight sequencing, pointing control and stabilization, and telemetry formatting. A description of the telescope, helium-cooled detectors, and the orientation subsystems are presented together with a brief discussion of the proposed astronomical observations.

Silverberg, R. F.↗

A large-beam sky survey at millimeter and submillimeter wavelengths made from balloon altitudes

A survey has been made of a quarter of the celestial sphere from balloon altitudes with a telescope having a 1.6-deg beamwidth and two spectral bands: 3-10 kaysers and 10-25 kaysers. The limiting sensitivity of the survey was 10,000 Jy. The galactic disk was detected from 358 to 45 deg galactic longitude. The total far-infrared flux from several regions on the galactic plane measured in this survey is 5-10 times larger than that observed by others using smaller beamwidths and small-amplitude spatial chopping, indicating that a substantial part of the emission comes from extended sources. Two other extended sources were also observed, one in the Cygnus region and the other a spur running off the galactic plane at 130 deg galactic longitude toward the north celestial pole. In addition, lower limits for the spectral index of interstellar dust emission are presented.

Owens, D. K.↗

Near infrared photographic sky survey. 1: Catalog of red stellar objects

Red stellar objects for which V-1 was greater than a value of about 2 (supm). 5 were extracted from photographs of 23 program fields. Tabular data for each field show the object name; the 1950 epoch right ascension, declination, galactic longitude, galactic latitude; radial distance from field venter in decimal degrees; color classes; and objects ordered by redness.

Craine, E. R.↗

A dedicated 26-m SETI sky survey instrument facility: A feasibility study

The feasibility of converting a deactivated GSTDN 26 m facility into a dedicated SETI Instrument Facility is examined. Additional benefits that would accrue from the proposed utilization of these facilities are the capability for remote and control the Deep Space Communications Complex (DSCC) Signal Processing Center, combined with a reduction in ground-induced radio frequency interference due to the physical distance to the other DSCC front end areas and the Signal Processing Center.

Berman, A. L.↗

An Investigation of the Effects of Scan Separation on the Sensitivity of the SETI All Sky Survey for the Case of Gaussian Noise

The scalloping problem for the case of Gaussian noise statistics is analyzed. The optimal weighting strategy for linearly combining two observations in adjacent beam areas is derived, and the sensitivity and scalloping for this weighting strategy are compared with those realized using a single observation or using equal weighting of two observations. The variation of the probability for detecting ETI signals with scan separation are calculated for the various weighting strategies, assuming that the transmitters are of equal strength and are uniformly distributed throughout space.

Lokshin, A.↗

A simple technique for estimating EUVE sky survey exposure times

A simple way to estimate accumulated exposure time over the celestial sphere for a scanning telescope in earth orbit is described. Primary constraints on observation time, such as earth blockage, solar occultation, and passage through the South Atlantic Anomaly, are modeled using relatively straightforward, mainly closed-form geometrical solutions. The resulting algorithm is implemented on a desktop microcomputer. Though not rigorously precise, the algorithm is sufficient for conducting preliminary mission design studies for the Extreme Ultraviolet Explorer (EUVE).

Carlisle, G. L.↗

Radio astronomy aspects of the NASA SETI Sky Survey

The application of SETI data to radio astronomy is studied. The number of continuum radio sources in the 1-10 GHz region to be counted and cataloged is predicted. The radio luminosity functions for steep and flat spectrum sources at 2, 8, and 22 GHz are derived using the model of Peacock and Gull (1981). The relation between source number and flux density is analyzed and the sensitivity of the system is evaluated.

Klein, Michael J.↗

Emission-line galaxies in the third list of the Case Low-Dispersion Northern Sky Survey

Observations of 47 galaxies in the third Case list are reported. Thirty-five of the galaxies in the sample were selected for the presence of emission lines on the objective prism plates. At the higher spectral dispersion of the data, significant line emission was found in 46 of the 47 galaxies. Twenty-six galaxies are found to be undergoing significant bursts of star formation. Ten additional galaxies may be starburst galaxies with low-excitation spectra. Two galaxies are probably type Seyfert 2. The most distant object, CG 200, at a redshift of 0.144, has a strong broad H-alpha emission line, and is probably a Seyfert 1. Seventeen of the galaxies have been detected by IRAS. Eight of the IRAS galaxies have H-II-region-type spectra and eight have low-ionization starburst spectra. The galaxies represent a mixture of types, ranging from intrinsically faint dwarf galaxies with Mb equalling -16 mag, to powerful galaxies with MB equalling -23 mag. Galaxies CG 234 and CG 235 are interacting, as are galaxies CG 269 and CG 270.

Weistrop, Donna↗

ROSAT-IUE All Sky Survey (RIASS): First results on active galaxies

To optimize the activity of the RIASS collaboration was established between IUE and Rosat projects. Some of the results obtained are given and the importance of such coordinated observations for the Spectral Energy Distribution (SED) definition of Active Galactic Nuclei is illustrated. All the participants in the AGN part of the RIASS program are listed. The RIASS observations allow for a comprehensive study of the overall spectral energy distribution of AGN's. For the first time, data from different instruments can be used to determine the SED, since the observations were simultaneous. A preliminary analysis shows that the energies radiated in the UV and the soft X-rays domains are closely related. The spectra of individual objects as well as the correlation found between the intensity of CIV lambda 1550 emission line and the soft X-rays luminosity, suggest that the excess detected in this band is the high energy tail of the big UV bump.

Wamsteker, W.↗

The Guide Star Catalog and related sky surveys

The basic properties and foundations of the Guide Star Catalog (GSC) are presented. Special emphasis is given to the published versions of the GSC, and the project on image compression and distribution of the digitized survey plate scans is mentioned.

Jenkner, Helmut↗

Osse Sky Survey Observations for Cycles Three Extreme Red Egret Blazars

The original purpose of this work was to probe EGRET sources of low significance, and to use statistical techniques to construct a log N - log S of sources at greater than 50 MeV. At this writing, the detection significance of EGRET sources is still an issue. Therefore, we shifted our focus to the known EGRET detections. These came in two groups: (a) the known blazars; and (b) the high-Galactic latitude EGRET sources not identified with optical (or radio) counterparts.

Schachter, Jonathan F.↗

Compton Observatory EGRET All-Sky Survey

We describe the EGRET data products which we anticipate will suffice for virtually all guest and archival investigations. The production process, content, availability, format, and the associated software of each product is described. This paper also supplies sufficient detail for the archival researcher to do analysis which is not supported by extant software. Where published references don't exist, the EGRET team documentation is cited.

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