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Properties of individual X-ray sources: (Invited discourse)

Published online by Cambridge University Press:  14 August 2015

Laurence E. Peterson*
Affiliation:
Dept. of Physics, Space Physics Group, University of California, San Diego, La Jolla, Calif., U.S.A.

Abstract

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Observations to determine the spectra and time variations of hard X-rays from cosmic sources have been made from balloons and from the OSO-III satellite. These data have been obtained using actively collimated scintillation counters with apertures between 6 and 24° FWHM, areas between 10 and 50 cm2 and which operate over the 10–300 keV range. The Crab Nebula has been observed on three occasions over a 22-month period between September 1965 and July 1967. The power law spectrum has a number index of 2.0 ± 0.1. No long-term changes were observed over the 30–100 keV range with a limit at 3%/yr. A balloon search with a 10 cm2 Ge(Li) detector for X-ray lines at 62.5 keV, 110 keV and 180 keV due to heavy element radioactive decays which would be produced in the initial Crab explosion based on the Cf254 hypothesis has resulted in upper limits at about 10−3 γ-rays cm2-sec. This is about a factor of 20 above the predicted levels. Simultaneous X-ray and optical observations of SCO XR-1 from OSO-III confirm that X-ray and optical flaring are indeed coincident phenomena, and that although the X-ray intensity increases about a factor of two during the flare, the equivalent temperature of the excess radiation is nearly the same as that of the quiescent object. Upper limits, 95% confidence, on the flux of M-87 at 40 keV have been obtained. These are inconsistent with the flux of 1.2 × 10−4 photons/cm2-sec-keV reported in the literature. CYG X-1 has been observed to have a power law of number index 2.0 ± 0.2. The OSO-III has observed a number of sources in the southern skies including NOR XR-2 and the variable source Centaurus XR-2.

Type
Research Article
Copyright
Copyright © Reidel 1970 

References

Bowyer, S., Byram, E. T., Chubb, T. A., and Friedman, H.: 1964, ‘Lunar Occultation of X-Ray Emission from the Crab Nebula’, Science 146, 912.Google Scholar
Bradt, H., Mayer, W., Naranan, S., Rappaport, S., and Spada, G.: 1967, ‘Evidence for X-Radiation from the Radio Galaxy M-87’, Astrophys. J. Letters 150, L199.Google Scholar
Chodil, G., Mark, Hans, Rodrigues, R., Seward, F. D., and Swift, C. D.: 1967, ‘X-Ray Intensities and Spectra from Several Cosmic Sources’, Astrophys. J. 150, 57.Google Scholar
Chodil, G., Mark, Hans, Rodrigues, R., and Swift, C. D.: 1968a, ‘Nova-Like Behavior of the X-Ray Source Centaurus XR-2’, Astrophys. J. Letters 152, L45.Google Scholar
Chodil, G., Mark, Hans, Rodrigues, R., Seward, F. D., Swift, C. D., Turiel, Isaac, Hiltner, W. A., Wallerstein, George, and Mannery, E. J.: 1968b, ‘Simultaneous Observations of the Optical and X-Ray Spectra of SCO XR-1’, Astrophys. J. 154, 645.CrossRefGoogle Scholar
Clark, George W.: 1965, ‘Balloon Observation of the X-Ray Spectrum of the Crab Nebula above 15 keV’, Phys. Rev. Letters 14, 91.Google Scholar
Clayton, D. D. and Craddock, W. L.: 1965, ‘Radioactivity in Supernova Remnants’, Astrophys. J. 142, 189.CrossRefGoogle Scholar
Cocke, W. J., Disney, M. J., and Taylor, D. J.: 1969, Nature 221, 525.Google Scholar
Eggen, O. J., Freeman, Kenneth C., and Sandage, Allan: 1968, ‘On the Optical Identification of the X-Ray Source CEN XR-2 as WX CEN’, Astrophys. J. Letters 154, L27.Google Scholar
Fishman, G. J., Harnden, F. R., and Haymes, R. C.: 1970, this volume p. 116.Google Scholar
Friedman, H., Byram, E. T., and Chubb, T. A.: 1967, ‘Distribution and Variability of Cosmic X-Ray Sources’, Science 156, 3773, 374.Google Scholar
Fritz, G., Henry, R. C., Meekins, J. F., Chubb, T. A., and Friedman, H.: 1969, ‘X-Ray Pulsar in the Crab Nebula’, Science 164, 3880, 709.CrossRefGoogle ScholarPubMed
Frost, K. J., Rothe, E. D., and Peterson, Laurence E.: 1966, ‘A Search for the Quiet-Time Solar Gamma-Rays from Balloon Altitudes’, J. Geophys. Res. 71, 17, 4079.Google Scholar
Gatewood, George and Sofia, Sabatino: 1968, ‘Physical Characteristics of SCO X-1’, Astrophys. J. Letters 154, L69.Google Scholar
Giacconi, R., Gorenstein, P., Gursky, H., and Waters, J. R.: 1967, ‘An X-Ray Survey of the Cygnus Region’, Astrophys. J. Letters 148, L119.Google Scholar
Haymes, R. C., Ellis, D. V., Fishman, G. J., Kurfess, J. D., and Tucker, W. H.: 1968a, ‘Observation of Gamma Radiation from the Crab Nebula’, Astrophys. J. Letters 151, L9.Google Scholar
Haymes, R. C., Ellis, D. V., Fishman, G. J., Glenn, S. W., and Kurfess, J. D.: 1968b, ‘Detection of Gamma Radiation from the Cygnus Region’, Astrophys. J. Letters 151, L125.Google Scholar
Haymes, R. C., Ellis, D. V., Fishman, G. J., Glenn, S. W., and Kurfess, J. D.: 1968c, ‘Detection of Hard X-Radiation from Virgo’, Astrophys. J. Letters 151, L131.Google Scholar
Hicks, D. B., Reid, L. Jr., and Peterson, L. E.: 1965, ‘X-Ray Telescope for an Orbiting Solar Observatory’, IEEE Trans. Nucl. Sci. NS-12, 54.CrossRefGoogle Scholar
Hudson, H. S., Peterson, L. E., and Schwartz, D. A.: 1969, ‘Solar and Cosmic X-Rays above 7.7 keV’, Solar Phys. 6, 205.Google Scholar
Jacobson, A. S.: 1968, A Search for Gamma-Ray Line Emissions from the Crab Nebula, .Google Scholar
Jacobson, A. S.: 1969, The Gamma-Ray Line Spectrum of the Crab Nebula (UCSD Preprint).Google Scholar
Jerde, R. L., Peterson, L. E., and Stein, W.: 1967, ‘Effects of High Energy Radiations on Noise Pulses from Photomultiplier Tubes’, Rev. Sci. Instr. 38, 1387.Google Scholar
Johnson, H. M. and Golson, J. C.: 1968, ‘Narrow-Band and UBV Photometry of GX3-1 and Two Wolf-Rayet Stars’, Astrophys. J. Letters 154, L77.Google Scholar
Lewin, W. H. G., Clark, G. W., and Smith, W. B.: 1968a, ‘Observation of an X-Ray Flare from SCO X-1’, Astrophys. J. 152, L55.Google Scholar
Lewin, W. H. G., Clark, G. W., and Smith, W. B.: 1968b, ‘Observation of CEN XR-2 and Other High-Energy X-Ray Sources in the Southern Sky’, Astrophys. J. Letters 152, L49.CrossRefGoogle Scholar
Mook, Delo E.: 1967, ‘UBV Photometry of SCO XR-1’, Astrophys. J. 150, L25.Google Scholar
Neugebauer, G., Oke, J. B., Becklin, E., and Garmire, G.: 1969, ‘A Study of Visual and Infrared Observations of SCO XR-1’, Astrophys. J. 155, 1.Google Scholar
Overbeck, James W. and Tananbaum, Harvey D.: 1968, ‘Time Variations in Scorpius X-1 and Cygnus XR-1’, Astrophys. J. 153, 899.Google Scholar
Peterson, L. E.: 1966, ‘Upper Limits of the Cosmic Gamma-Ray Flux from OSO-I’, Space Research, Vol. VI, p. 53.Google Scholar
Peterson, L. E. and Jacobson, A. S.: 1966, ‘The Spectrum of SCO XR-1 to 50 keV’, Astrophys. J. 145, 962.CrossRefGoogle Scholar
Peterson, L. E., Jerde, R. L., and Jacobson, A. S.: 1967, ‘Balloon X-Ray Astronomy’, AIAA J. 5, 1921.CrossRefGoogle Scholar
Peterson, L. E., Jacobson, A. S., Pelling, R. M., and Schwartz, D. A.: 1968, ‘Observations of Cosmic X-Ray Sources in the 10–250 keV Range (Presented at 10th International Cosmic Ray Conference, Calgary, Canada, June 1967) Can. J. Phys. 46, S437.Google Scholar
Riegler, G. and Ramaty, R.: 1969, ‘Physical Properties of the Radio-Emitting Region of SCO X-1 (GSFC X-611-69-123)’; Preprint March.Google Scholar
Sartori, L. and Morrison, P.: 1967, ‘Thermal X-Rays from Non-Thermal Radio Sources’, Astrophys. J. 150, 385.CrossRefGoogle Scholar
Schwartz, D. A., Hudson, H. S., and Peterson, L. E.: 1968, ‘Satellite Observation of the X-Ray Source in Lupus’, Preprint January 1969.Google Scholar
Trimble, Virginia: 1968, ‘Motions and Structure of the Filamentary Envelope of the Crab Nebula’, Astron. J. 73, 535.Google Scholar
Vette, J. I., Matteson, J. L., Gruber, D., and Peterson, L. E.: 1970, this volume p. 355.Google Scholar
Westphal, J. A., Sandage, Allan, and Kristian, Jerome: 1968, ‘Rapid Changes in the Optical Intensity and Radial Velocities of the X-Ray Source SCO X-l’, Astrophys. J. 154, 139.CrossRefGoogle Scholar