Engineering topics

Szymkowiak, A.

Publications and source records attributed to Szymkowiak, A..

7 records

NASA NTRS1993

BBXRT observations of supernova remnants

The Broad Band X-ray Telescope (BBXRT) was designed to perform sensitive, moderate resolution spectroscopy of cosmic X-ray sources in the 0.3-10 keV band from the Space Shuttle. During its nine-day flight in December, 1990, the BBXRT observed a variety of supernova remnants and related objects. We present results from some of these observations, emphasizing the ability of the BBXRT to perform spatially-resolved spectroscopy. The improved specral resolution and efficiency over previous instruments makes possible measurements of previously undetectable lines, and the broad bandpass allows simultaneous measurements of lines from oxygen through iron.

Petre, R.↗

NASA NTRS1993

Broad-Band X-Ray Telescope spectroscopy of Xi Puppis

The Broad-Band X-Ray Telescope obtained moderate-resolution (about 90 eV) X-ray spectra of the O4 f star Xi Pup during the STS 35/Astro 1 mission in 1990 December. Despite the shortness of the observation (600 s), the data show a surprising amount of detail. We report the detection of an O absorption edge produced by ionized overlying wind material and K-shell line emission from Mg produced by a thermal plasma of temperature near 6 x 10 exp 6 K. The data are used to place constraints on the location, temperature, and amount of the X-ray-emitting gas, as well as the abundance and ionization of the wind material.

Corcoran, M. F.↗

NASA NTRS1990

Thermal detection of X-rays

The development of calorimeters is described in terms of their proposed application to sounding-rocket investigations of cosmic X-ray sources. The fundamental theory of the energy resolution of the devices is given, and general discussions are presented regarding the limitations associated with the materials used and available thermometer types. Also given are data describing electrical nonlinearity as a function of temperature, thermistor sensitivity, and heat capacity, as well as data regarding the excess noise that aids in the conduction process. Cryogenic calorimeters based on doped semiconductor thermistors are found to be limited, although thermal detectors have important applications to high-resolution laboratory spectroscopy. Electrical nonlinearity and the excess noise are found to be important for obtaining optimum heat capacity in the thermistor.

Mccammon, D.↗

NASA NTRS1990

Observing soft X-ray line emission from the interstellar medium with X-ray calorimeter on a sounding rocket

For an X-ray calorimeter working at 0.1 K, the energy resolution ideally can be as good as one eV for a practical detector. A detector with a resolution of 17 eV FWHM at 6 keV has been constructed. It is expected that this can be improved by a factor of two or more. With X-ray calorimeters flown on a sounding rocket, it should be possible to observe soft X-ray line emission from the interstellar medium over the energy range 0.07 to 1 keV. Here, a preliminary design for an X-ray calorimeter rocket experiment and the spectrum which might be observed from an equilibrium plasma are presented. For later X-ray calorimeter sounding rocket experiments, it is planned to add an aluminum foil mirror with collecting area of about 400 sq cm to observe line features from bright supernova remnants.

Zhang, J.↗

NASA NTRS1986

Infrared studies of supernova remnants with the IRAS

A comparative study of the infrared and X-ray fluxes and morphologies of supernova remnants (SNR) can yield valuable information on their evolution and on their interaction with the smbient interstellar medium (ISM).

Dwek, E.↗

NASA NTRS1984

The X-ray nebula around PSR 1509 - 58

With the use of measured spectra and a model, volumes and luminosities are derived for several components of the supernova remnant MSH 15 - 52. The hard, featureless spectrum and spatial symmetry of the X-ray nebula surrounding the central pulsar strongly indicate synchrotron radiation as the source of emission. Power requirements are easily supplied by the pulsar. The observed surface brightness is only 0.00002 that of the X-ray synchrotron emission around the Crab pulsar, and the X-ray luminosity is 0.01 that of the Crab. In spite of the great difference in luminosity and size, the two systems are probably similar in nature, with the high brightness and unique appearance of the Crab synchrotron nebula being due to the high energy output of the pulsar and the relatively small volume of the confining filaments.

Seward, F. D.↗

NASA NTRS1984

X-rays from Eta Carinae

X-ray observations of Eta Car obtained with the high-resolution imager and solid-state spectrometer of the Einstein observatory are reported and interpreted in terms of a two-shell model. A soft component with temperature 5 million K is located in the expanding outer shell, and the hard core component with temperature 80 million K is attributed to the interaction of a high-velocity stellar wind from the massive central object with the inner edge of a dust shell. Model calculations based on comparison with optical and IR data permit estimation of the mass of the outer shell (0.004 solar mass), the mass of the dust shell (3 solar mass), and the total shell expansion energy (less than 2 x 10 to the 49th ergs).

Chlebowski, T.↗