X-ray Observations of SNR E0102.2-72.2 in the SMC

AbstractThe supernova remnant (SNR) E0102.2-72.2 is the brightest in the Small Magellanic Cloud (SMC) at X-ray wavelengths. This object, which is remarkable because of its high velocity (∼4000 km s−1) oxygen-rich optical emission, appears to be similarly remarkable at X-ray wavelengths. The high resolution imager (HRI) data can be quite well described by a thick ring with a radius of ∼19" (6 pc at a distance of 63 kpc). The imaging proportional counter (IPC) X-ray spectral data can be best fit by a single emission line of energy ∼0.9 keV. It seems likely that this is the emission from a plasma of almost pure neon.

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Detailed X-ray Observations of the Cygnus Loop

Symposium - International Astronomical Union ◽

10.1017/s0074180900033969 ◽

1983 ◽

Vol 101 ◽

pp. 253-260

Author(s):

W. H.-M. Ku ◽

K. Long ◽

R. Pisarski ◽

M. Vartanian

Keyword(s):

High Resolution ◽

Proportional Counter ◽

Supernova Remnant ◽

Sounding Rocket ◽

Loop Structure ◽

High Quality ◽

Radio Structure ◽

X Ray ◽

Cygnus Loop ◽

Spatially Resolved

High quality X-ray spectral and imaging observations of the Cygnus Loop have been obtained with three different instruments. The High Resolution Imager (HRI) on the Einstein Observatory was used to obtain arcsecond resolution images of select bright regions in the Cygnus Loop which permit detailed comparisons between the X-ray, optical, and radio structure of the Loop. The Imaging Proportional Counter (IPC) on the Einstein Observatory was used to obtain an arcminute resolution map of essentially the full Loop structure. Finally, an Imaging Gas Scintillation Proportional Counter (IGSPC), carried aloft by a sounding rocket last fall, obtained modest resolution, spatially resolved spectrophotometry of the Cygnus Loop. An X-ray map of the Loop in the energy of the 0 VIII line was obtained. These data combine to yield a very powerful probe of the abundance, temperature, and density distribution of material in the supernova remnant, and in the interstellar medium.

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High Resolution Radio Observations of the SNR G160.9+2.6 (HB9)

International Astronomical Union Colloquium ◽

10.1017/s0252921100102556 ◽

1988 ◽

Vol 101 ◽

pp. 301-304

Author(s):

D.A. Leahy ◽

R.S. Roger

Keyword(s):

High Resolution ◽

Surface Brightness ◽

Supernova Remnant ◽

Optical Emission ◽

Continuum Emission ◽

Filamentary Structure ◽

X Ray ◽

Significant Spatial Variation ◽

Optical Structure ◽

The Continuum

AbstractG160.9+2.6 (HB9) is a supernova remnant of large angular diameter and low radio surface brightness. We report new observations of the continuum emission from HB9 at 408 MHz and 1420 MHz with angular resolutions of 3.5’ and 1.0#x2019;, respectively, which reveal significant filamentary structure not previously detected. The 1420 MHz field covers only the central and eastern parts of HB9. The 408-1420 MHz spectral index (S∝vα) of regions common to both maps is α=-0.68, with no significant spatial variation. The radio filamentary structure closely follows the optical structure. X-ray emission from HB9 is more centrally concentrated than the radio or optical emission. The radio, optical, and particularly, the X-ray surface brightness are all diminished in the northern and northwestern portions of the remnant, in directions approximately coincident with an extensive molecular cloud detected in CO.

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Herculis X1: Results and Interpretation

Symposium - International Astronomical Union ◽

10.1017/s0074180900160747 ◽

1987 ◽

Vol 125 ◽

pp. 201-201

Author(s):

Ph. Durouchoux

Keyword(s):

High Resolution ◽

Emission Line ◽

Absorption Line ◽

X Ray ◽

First Time ◽

Best Fit

The hard X-ray spectrum of Her X1 was measured for the first time with a high-resolution (1.4 keV FWHM) germanium spectrometer (LEGS: GSFC/Saclay collaboration). The observation was performed near the peak of the 0B state in the 35 day cycle and 1.24 s pulsations were observed between the energies of 20 keV and 70 keV. The best fit energies are 35 keV for an absorption line and 39 keV for an emission line. These are significantly lower energies than those derived from previous experiments.

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A High Resolution, High Efficiency Proportional Counter X-Ray Camera

IEEE Transactions on Nuclear Science ◽

10.1109/tns.1973.4326926 ◽

1973 ◽

Vol 20 (1) ◽

pp. 333-333 ◽

Cited By ~ 3

Author(s):

Richard N. St. Onge

Keyword(s):

High Resolution ◽

Proportional Counter ◽

High Efficiency ◽

X Ray

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Non-Equilibrium Ionization in Puppis A

Symposium - International Astronomical Union ◽

10.1017/s0074180900033957 ◽

1983 ◽

Vol 101 ◽

pp. 245-252

Author(s):

P. F. Winkler ◽

C. R. Canizares ◽

B. C. Bromley

Keyword(s):

High Resolution ◽

Spectroscopic Data ◽

Supernova Remnant ◽

Optical Data ◽

Equilibrium Conditions ◽

X Ray ◽

Flux Measurements ◽

Far From Equilibrium ◽

Einstein Observatory ◽

Non Equilibrium

High resolution X-ray spectroscopy of the brightest knot of emission in the Puppis A supernova remnant shows that it is made up of ionizing plasma, far from equilibrium. Flux measurements in several X-ray lines enable us to determine the non-equilibrium conditions: electron temperature, ion populations, and time since the knot was heated by the supernova shock. Imaging and spectroscopic data from the Einstein Observatory together suggest that this knot is a cloud of density about 10 cm−3 which has recently been shocked to a temperature 7 × 106 K. Radio and optical data on the region appear consistent with this picture.

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A new high-resolution small-angle X-ray scattering apparatus using a fine-focus rotating anode, point-focusing collimation and a position-sensitive proportional counter

Journal of Applied Crystallography ◽

10.1107/s0021889884011614 ◽

1984 ◽

Vol 17 (5) ◽

pp. 337-343 ◽

Cited By ~ 4

Author(s):

O. Yoda

Keyword(s):

High Resolution ◽

Small Angle ◽

Proportional Counter ◽

Anisotropic Scattering ◽

Photon Flux ◽

X Rays ◽

X Ray ◽

X Ray Scattering ◽

Position Sensitive ◽

Ray Scattering

A high-resolution small-angle X-ray scattering camera has been built, which has the following features. (i) The point collimation optics employed allows the scattering cross section of the sample to be directly measured without corrections for desmearing. (ii) A small-angle resolution better than 0.5 mrad is achieved with a camera length of 1.6 m. (iii) A high photon flux of 0.9 photons μs−1 is obtained on the sample with the rotating-anode X-ray generator operated at 40 kV–30 mA. (iv) Incident X-rays are monochromated by a bent quartz crystal, which makes the determination of the incident X-ray intensity simple and unambiguous. (v) By rotation of the position-sensitive proportional counter around the direct beam, anisotropic scattering patterns can be observed without adjusting the sample. Details of the design and performance are presented with some applications.

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The optical counterpart of the ultraluminous X-ray source NGC6946 ULX-1

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307005029 ◽

2006 ◽

Vol 2 (S238) ◽

pp. 229-232

Author(s):

P. K. Abolmasov ◽

S. N. Fabrika ◽

O. N. Sholukhova

Keyword(s):

Emission Line ◽

Spectral Data ◽

Line Source ◽

Total Power ◽

High Excitation ◽

Optical Counterpart ◽

Additional Source ◽

X Ray ◽

Long Time ◽

Integral Field

AbstractWe present a study of a peculiar nebula MF16 associated with an Ultraluminous X-ray Source NGC6946 ULX-1. We use integral-field and long-slit spectral data obtained with the 6-m telescope (Russia). The nebula was for a long time considered powered by strong shocks enhancing both high-excitation and low-excitation lines. However, kinematical properties point to rather moderate expansion rates (VS ∼ 100÷200 km s−1). The total power of the emission-line source exceeds by one or two orders of magnitude the power observed expansion rate can provide, that points towards the existence of an additional source of excitation and ionization. Using CLOUDY96.01 photoionization code we derive the properties of the photoionizing source. Its total UV/EUV luminosity must be about 1040 erg/s.

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