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Mckee, J. D.

Publications and source records attributed to Mckee, J. D..

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

HEAO A-2 observations of non-Abell Zwicky clusters containing extended radio sources

Burns and Owen's sample of 25 4C radio sources which coincide with Zwicky clusters of galaxies has been searched for X-ray emission using the HEAO 1 A-2 experiment. X-ray emission was detected from five sources at the 3sigma level, two of which exceeded 5sigma. Positions and 90% X-ray error boxes are given for each of the five sources detected. The clusters surveyed are non-Abell clusters which would generally not be expected to be detectable with the A-2 experiment. The search for X-ray emission was prompted by the knowledge of the existence of extended radio sources in the clusters. The relaxed structure of these sources implies the presence of a relatively dense intracluster medium which is expected to produce thermal bremsstrahlung X-ray emission.

Holman, G. D.↗
NASA NTRS1980

The HEAO A-2 survey of Abell clusters and the X-ray luminosity function

A statistically complete sample of 225 Abell clusters has been examined. Twelve new identifications of clusters with X-ray sources have been made. It is found that (1) Lx is roughly correlated with richness for richness classes 0, 1, and 2; (2) Lx is well correlated with Rood-Sastry type and only loosely correlated with Bautz-Morgan type; and (3) the cluster contribution to the X-ray background is less than or equal to 5% between 2 and 10 keV.

Mckee, J. D.↗
NASA NTRS1980

Soft X-ray sources in the bar of the Large Magellanic Cloud

X-ray observations of the Large Magellanic Cloud were made with two collimated proportional counters having high angular resolution, a wide spectral dynamic range and a large aperture. Counting rates in the two detectors during the entire rocket flight are presented, and a number of soft X-ray (0.5-2 keV) sources were found in the bar of the LMC, having luminosities between 10 to the 37th and 10 to the 38th ergs/s. Emission in the 0.15-0.28 keV band from LMC X-3 was also detected.

Mckee, J. D.↗
NASA NTRS1980

The HEAO A-2 survey of Abell clusters and the X-ray luminosity function

The HEAO A-2 all sky data base was surveyed for 2-10KeV X-rau emission from the 225 Abell clusters og galaxies listed in Abell's (1958) catalog which are of distance class four or less, and are within the fraction of the sky surveyed completely by Abell. Thirty-two identifications of clusters with X-ray sources were made, for which 2-10 KeV fluxes and 90% error boxes are presented. Twelve of these identification are new. The X-ray luminosity function was derived for this statistically complete sample and the best exponential fit was found to be f(L) = 20.2 x 10 to the minus 8 power exp (-l(44)/1.9) per cu Mpc 2-10KeV. The relationship between X-ray luminosity and richness was examined and a correlation was found for richness classes 0, 1, and 2. The relationship of X-rau luminosity, Bautz-Morgan type, and Rood-Sastry type was examined. It was found that BM type I's and RS type cD and B have the greatest average luminosity. The contribution of clusters to the X-ray background was calculated from the luminosity function and was found to be 5%, and with 90% certainty, less than 8% in the 2-10 KeV band pass.

Mckee, J. D.↗
NASA NTRS1979

X-ray locations and sizes of clusters of galaxies observed with the HEAO 1 scanning modulation collimator

Observations with the HEAO 1 scanning modulation collimator (MC) have yielded improved locations for the centroids of X-ray sources in clusters of galaxies dominated by a giant central galaxy. For A85, A478, A1795, A2029, A2199, A2319 A, and SC 0316-444, these positions are consistent with those of the clusters' dominant cD galaxies. By comparing the HEAO 1 MC flux with that obtained with the HEAO 1 A-2 experiment, estimates of the X-ray sizes for these clusters have been obtained. The correlation of these sizes with other cluster properties is discussed.

Schwarz, J.↗
NASA NTRS1977

A new measurement of the spin-up rate of SMC X-1

Observations of the X-ray pulsar, SMC X-1, made from an Aerobee rocket and an Apollo spacecraft have been re-analyzed. The rotation periods found have been combined with observations made from Uhuru, SAS-3, and Ariel 5 to obtain a new measurement of the spin-up rate of SMC X-1.

Yentis, D.↗