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Hazard, C.

Publications and source records attributed to Hazard, C..

10 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

A radio-quiet galaxy at redshift z = 3.409

The discovery of an unresolved radio-quiet object with a redshift of 3.409 and visual magnitude of 24.3 +/-0.5 is reported. The object was identified during an imaging search for Ly-alpha emission near the redshift of a z(abs) = 3.390-damped Ly-alpha absorption-line system which appears in the spectrum of the z(em) = 4.11 QSO 0000-2619. It is determined that the bulk of the object's Ly-alpha and continuum emission comes from an unresolved region less than 9 kpc, and its absolute magnitude in the rest-frame UV near Ly-alpha is about -21.2. A long-slit CCD spectrum at 500 km/s resolution shows that it has kinematically unresolved Ly-alpha emission with a rest equivalent width in the range of about 10-20 A. The object is observed to be about 135 kpc in projection from the sight line to the WSO. No emission at the redshift of the damped Ly-alpha absorber is detected.

Turnshek, D. A.↗
NASA NTRS1984

The role of the Automated Plate Measuring (APM) machine in developing a program to discover QSOs automatically

The scanning of a direct plate with the automatic plate measuring machine which results in the automated selection and description of images is described. The selection of QSO candidates based on color-color diagrams constructed from the APM image data and the analysis of APM raster data for QSOs selected visually from objective prism plates are also discussed.

Turnshek, D.↗
NASA NTRS1977

Spectrophotometric observations of Molonglo radio source identifications

The paper presents spectrophotometric observations of 76 optical objects identified with radio sources from the MC2 and MC3 catalogs. Line intensities, equivalent widths, line widths, and optical spectral indices are presented for 44 objects confirmed as quasi-stellar objects. The statistical and physical properties of the Molonglo sample are briefly discussed.

Smith, H. E.↗
NASA NTRS1976

The redshift of 0938+119

Results are reported for digicon spectrophotometric observations of the radio source 0938+119, which was originally classified as a faint red galaxy. A prism spectrum of the source is presented along with the corresponding sky measurement, and several features of the spectrum are described. It is shown that this source is a QSO with a magnitude of 20.1, a redshift z = 3.19, and a spectrum similar to that of OH 471 or 4C 05.34. The question of whether other faint high-redshift QSOs have been misclassified as galaxies is considered.

Beaver, E. A.↗
NASA NTRS1973

A double quasistellar object

It is reported that 1548+115a is also a QSO. Spectral information is provided for 1548+115b and 1548+115a, giving attention to the very different redshifts of the objects. The observations reported are believed to add support to noncosmological theories of redshifts. Such theories will receive additional support if an interaction between the two components of a close pair can be shown.

Wampler, E. J.↗
NASA NTRS1973

Discrepant redshifts of QSOs in clusters of galaxies and a close QSO pair

The question is investigated whether QSO redshifts are cosmological in origin, taking into account the possibility that QSOs may be more local objects. A search is made for situations in which more than one blue stellar object (BSO) lay close to a radio position selected from the 4C catalog. It is found that in all four examples studied the radio emission arises in the QSO and not the galaxies or cluster of galaxies.

Hazard, C.↗
NASA NTRS1973

A spectroscopic survey of 92 QSO candidates

Spectra obtained for 92 QSO candidates selected mostly on the basis of their proximity to radio-source positions are presented. Thirty-two were classified as QSOs on the basis of broad emission lines and stellar appearance, whereas redshifts were determined in 14 instances.

Baldwin, J. A.↗
NASA NTRS1973

The absorption line spectrum of 1331 + 170.

The absorption-rich optical and near-infrared spectrum of the quasi-stellar object 1331 + 170 is analyzed. The emission-line redshift is about 2.08, and at least three absorption systems are shown to be present; the absorption redshifts are 1.7755, 1.7851, and 1.9637. We conclude that the absorbing material giving rise to the three systems is intrinsic to the QSO despite the high velocity difference between emission and absorption systems and the low velocity dispersion within each absorption system.

Strittmatter, P. A.↗