Space Science Reviews

, Volume 72, Issue 3–4, pp 499–592 | Cite as

Characteristics of nearby interstellar matter

  • Priscilla C. Frisch
Article

Abstract

There is a warm tenuous partially ionized cloud (T∼104 K,n(HI)∼0.1 cm−3,n(Hii∼ 0.22–0.44 cm−3) surrounding the solar system which regulates the environment of the solar system, determines the structure of the heliopause region, and feeds neutral interstellar gas into the inner solar system. The velocity (V∼−20 km s−1 froml∼335°,b∼0° in the local standard of rest) and enhanced Caii and Feii abundances of this cloud suggest an origin as evaporated gas from cloud surfaces in the Scorpius-Centaurus Association. Although the soft X-ray emission attributed to the ‘Local Bubble’ is enigmatic, optical and ultraviolet data are consistent with bubble formation caused by star formation epochs in the Scorpius-Centaurus Association as regulated by the nearby spiral arm configuration. The cloud surrounding the solar system (the ‘local fluff’) appears to be the leading region of an expanding interstellar structure (the ‘squall line’) which contains a magnetic field causing polarization of the light of nearby stars, and also absorption features in nearby upwind stars. The velocity vectors of the solar system and local fluff are perpendicular in the local standard of rest. Combining this information with the low column densities seen towards Sirius in the anti-apex direction, and the assumption that the cloud velocity vector is parallel to the surface normal, suggests that the Sun entered the local fluff within the historical past (less than 10 000 years ago) and is skimming the surface of the cloud. Comparison of magnesium absorption lines towards Sirius and anomalous cosmic-ray data suggest the local fluff is in ionization equilibrium.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Adams, W. S.: 1949, ‘Observations of Interstellar Caii H and K, Molecular Lines, and Radial Velocities in the Spectra of 300 O and B Stars’,Astrophys. J. 109, 354–379.Google Scholar
  2. Adams, T. F. and Frisch, P. C.: 1977, ‘High-Resolution Observations of the Lyman Alpha Sky Background’,Astrophys J. 212, 300–308.Google Scholar
  3. Adams, J. H., Jr., Garcia-Munoz, M., Grigorov, N. L., Klecker, Bl., Kondratyeva, M. A., Mason, G. M., McGuire, R.E., Mewaldt, R. A., Panasyuk, M. I., and Tretyakova, Ch. A.: 1991, ‘The Charge State of the Anomalous Component of Cosmic Rays’,Astrophys. J. 375, L45–49.Google Scholar
  4. Adler, D. S. and Westpfahl, D. J.: 1994, ‘HI Aperture Synthesis Images of M81’,183rd Astron. Astrophys. Meeting, January, Washington, D.C.Google Scholar
  5. Ajello, J. M., Stewart, A. I., Thomas, G. E., and Graps, A.: 1987, ‘Solar Cycle Study of Interplanetary Lα Variations: Pioneer Venus Orbiter Sky Background Results’,Astrophys. J. 317, 964.Google Scholar
  6. Alfaro, E. J., Cabrera-Cano, J., and Delgado, A. J.: 1991 ‘Topography of the Galactic Disk: Z-Structure and Large-Scale Star Formation’,Astrophys. J. 378, 106–118.Google Scholar
  7. Allan, R. J., Clegg, R. E. S., Dickinson, A. S., and Flower, D. R.: 1988, ‘Mg−H+ Charge Transfer and Mg Line Intensities in Gaseous Nebulae’,Monthly Notices Roy. Astron. Soc. 235, 1245.Google Scholar
  8. Anantharamiah, K. R., Radhakrishnan, V., and Shaver, P. A.: 1984, ‘On the Statistics of GalacticHI Clouds’,Astron. Astrophys. 138, 131–139.Google Scholar
  9. Arnaud, M. and Rothenflug, R.: 1986, ‘Heating of the Local Interstellar Medium’,Adv. Space Res. 6, 129–138.Google Scholar
  10. Arnaud, M., Rothenflug, R., and Rocchia, R.: 1984, ‘The Local Hot Bubble from X-Ray Spectroscopic Measurements’,Physica Scripta T7, 48–49.Google Scholar
  11. Baliunas, S. L. and Dupree, A. K.: 1979, ‘Ultraviolet and Optical Spectroscopic Studies of λ Andromedae: The Chromosphere and Interstellar Matter’,Astrophys. J. 227, 870.Google Scholar
  12. Baranov, V. B., Lebedev, M. G., and Ruderman, M. S.: 1979, ‘Structure of the Region of Solar Wind-Interstellar Medium Interaction and Its Influence on H Atoms Penetrating the Solar Wind’,Astrophys. Space Sci. 66, 441–451.Google Scholar
  13. Baranov, V. B., Lebedev, M. G., and Malama, Ju. G.: 1991, ‘The Influence of the Interface between the Heliosphere and the Local Interstellar Medium on the Penetration of the H Atoms to the Solar System’,Astrophys. J. 375, 347–351.Google Scholar
  14. Barlow, M. J. and Silk, J.: 1977, ‘Sputtering in Interstellar Shocks: A Model for Heavy Element Depletion’,Astrophys. J. 211, L83-L87.Google Scholar
  15. Barstow, M. A., Holberg, J. B., Werner, K., Buckley, D. A. H., and Stobie, R. S.: 1993a, ‘The Nature of the Newly Discovered DO White Dwarf, RE0503-289’,Monthly Notices Roy. Astron. Soc., in press.Google Scholar
  16. Barstow, M. A., Wesemael, F., Holberg, J. B., Werner, K., Buckley, D. A. H., Stobie, R. S., Fontaine, G., Rosen, S. R., Demers, S., Lamontagne, R., Irwin, M. J., Bergeron, P., Kepler, S. O., and Vennes, S.: 1993b, ‘Two New Hot White Dwarfs in a Region of Exceptionally LowHI Density’,Adv. Space Res. 13, 281–285.Google Scholar
  17. Barstow, M. A., Wesemael, F., Holberg, K., Buckley, D. A. H., Stobie, R. S., Mittaz, J. P. D., Fontaine, G., Rosen, S. R., Demers, S., Lamontagne, R., Irwin, M. J., Bergeron, P., Kepler, S. O., and Vennes, S.: 1994, ‘A New Hot DA White Dwarf in a Region of Exceptionality LowHI Density’,Monthly Notices Roy. Astron. Soc., in press.Google Scholar
  18. Berkhuijsen, E. M.: 1971, ‘A Survey of the Continuum Radiation at 820MHz between Declinations −7° and +85°’,Astron. Astrophys. 14, 359–386.Google Scholar
  19. Bertaux, J. L., Lallement, R., Kurt, V. G., and Mironova, E. N.: 1985, ‘Characteristics of the Local Interstellar Hydrogen Determined from Prognoz 5 and 6 Interplanetary Lyman α Profile Measurements with a Hydrogen Absorption Cell’,Astron. Astrophys. 150, 1.Google Scholar
  20. Bertaux, J. L. and Blamont, J. E.: 1971, ‘Evidence for a Source of Extraterrestrial Hydrogen Lyman-α Emission: The Interstellar Wind’,Astron. Astrophys. 11, 200–217.Google Scholar
  21. Bertin, P., Lallement, R., Ferlet, R., and Vidal-Madjar, A.: 1993, ‘NaI/Caii Ratio in the Local Interstellar Medium’,Astron. Astrophys. 278, 549–560.Google Scholar
  22. Bignami, G. G., Caraveo, P. A., and Mereghetti, S.: 1993, ‘The Proper Motion of Geminga's Optical Counterpart’,Nature 361, 704–706.Google Scholar
  23. Black, J. H. and Dalgarno, A.: 1977, ‘Models of Interstellar Clouds. I. The Zeta Ophiuchi Cloud’,Astrophys. J. Suppl. Ser. 34, 405–423.Google Scholar
  24. Bloch, J. J., Jahoda, K., Juda, M., McCammon, D., Sanders, W. T., and Snowden, S. L.: 1986, ‘Observations of the Soft X-Ray Diffuse Background at 0.1 keV’,Astrophys. J. 308, L59.Google Scholar
  25. Bochkarev, N. G.: 1984, ‘Large-Scale Bubble Structure of the Interstellar Medium and Properties of the Local Spiral Arm’,IAU Colloq. 81, 305–309.Google Scholar
  26. Bochkarev, N. G.: 1987, ‘Local Interstellar Medium’,Astrophys. Space Sci. 138, 229–302.Google Scholar
  27. Boggess, A., Bruhweiler, F. C., Grady, C. A., Ebbets, D. C., Kondo, Y. H., Trafton, L. M., Brandt, J. C., and Heap, S. R.: 1991, ‘First Results from the GHRS: Resolved Velocity and Density Structure in the β Pictoris Circumstellar Gas’,Astrophys.J. 377, L49-L52.Google Scholar
  28. Bohlin, R. C., Savage, B. D., and Drake, J. F.: 1978, ‘Survey of Interstellar HI from Lα Absorption Measurements, II’,Astrophys. J. 224, 132–142.Google Scholar
  29. Bohlin, R. C., Hill, J. K., Jenkins, E. B., Savage, B. D., Snow, T. P., Spitzer, L., and York, D. G.: 1983, ‘Survey of Ultraviolet Interstellar Lines: Velocities and Equivalent Widths’,Astrophys. J. Suppl. Ser. 51, 277–320.Google Scholar
  30. Bohlin, R. C., Savage, B. D., and Drake, J. F.: 1978, ‘Survey of Interstellar HI from L alpha Absorption Measurements. II’,Astrophys. J. 224, 132–142.Google Scholar
  31. Bohm-Vitense, E.: 1981, ‘Interstellar Absorption in the Mgii Resonance Line Emissions’,Astrophys. J. 244, 504–510.Google Scholar
  32. Boksenberg, A., Kirkham, B., Pettini, M., Bates, B., Carson, P. P. D., Dufton, P. L., and McKeith, C. D.: 1975, ‘Interstellar Magnesium Absorption in the Direction of Four Unreddened Stars’,Astrophys. J. 202, L91-L96.Google Scholar
  33. Borken, R. J. and Iwan, D. C.: 1977, ‘Spatial Structure in the Soft X-Ray Background as Observed from OSO-8, and the North Polar Spur as a Reheated Supernova Remnant’,Astrophys. J. 218, 511–520.Google Scholar
  34. Boulares, A. and Cox, D. P.: 1990, ‘Galactic Hydrostatic Equilibrium with Magnetic Tension and Cosmic Ray Diffusion’,Astrophys. J. 365, 544–555.Google Scholar
  35. Bregman, J. N., Kelson, D. D., and Ashe, G. A.: 1993, ‘Modeling the Structure of HI in the Galactic Disk’,Astrophys. J. 409, 682–690.Google Scholar
  36. Bruhweiler, F. C. and Kondo, Y.: 1982a, ‘Detection of Interstellar CI in the Immediate Vicinity of the Sun’,Astrophys. J. 260, L91-L94.Google Scholar
  37. Bruhweiler, F. C.: 1984, in F. Bruhweiler, Y. Kondo, and B. D. Savage (eds.), ‘Absorption Line Studies and the Distribution of Neutral Gas in the Local Interstellar Medium’,IAU Colloq. 81, 39.Google Scholar
  38. Bruhweiler, F. C. and Kondo, Y.: 1982b, ‘UV Spectra of Nearby White Dwarfs and the Nature of the Local Interstellar Medium’,Astrophys. J. 259, 232–238.Google Scholar
  39. Bruhweiler, F. C. and Vidal-Madjar, A.: 1987, in Y. Kondo (ed.), ‘The Interstellar Medium Near the Sun’,Scientific Accomplishments of the IUE, D. Reidel Publ. Co., Dordrecht, Holland, pp. 467–484.Google Scholar
  40. Bruhweiler, F. C., Oegerle, W., Weiler, E., Stencel, R., and Kondo, Y.: 1984, in F. Bruhweiler, Y. Kondo, and B. D. Savage (eds.), ‘Observations of Local Interstellar MgI and Mgii’,IAU Colloq. 81, 39.Google Scholar
  41. Burrows, D. N.: 1989, ‘Observational Constraints on an Embedded Cloud Model for the Soft X-Ray Diffuse Background’,Astrophys. J. 340, 775.Google Scholar
  42. Burrows, DD. N. and Mendenhall, J. A.: 1991,Nature 351, 629.Google Scholar
  43. Bzowski, M.: 1988, ‘Local Interstellar Wind Velocity from Doppler Shifts of Interstellar Matter Lines’,Acta Atron. 38, 443–453.Google Scholar
  44. Cappa de Nicolau, C. E. and Poppel, W. G. L.: 1986, ‘The Interstellar Medium in the Vicinity of the Association Sco OB2’,Astron. Astrophys. 164, 274–299.Google Scholar
  45. Centurion, M. and Vladilo, G.: 1991, ‘The Local Interstellar Medium Toward the Center of Loop I’,Astrophys. J. 372, 494–592.Google Scholar
  46. Centurion, M., Vladilo, G., Molaro, P., and Beckman, J. E.: 1986, ‘Ultraviolet Interstellar Lines Towards Nearby Fast Rotators: Znii Distribution and Mgii/MgI Ratios’,Adv. Space Res. 6, 43–46.Google Scholar
  47. Cheng, K.-P. and Bruhweiler, F. C.: 1990, ‘Ionization Processes in the Locai Interstellar Medium: Effects of the Hot Coronal Substrate’,Astrophys. J. 364, 573–580.Google Scholar
  48. Christian, E. R.: 1989, ‘Evidence for Anomalous Cosmic Ray Hydrogen’, Ph.D. Thesis, California Institute of Technology.Google Scholar
  49. Clarke, J. T., Bowyer, S., Fahr, H. J., and Lay, G.: 1985, ‘IUE High Resolution Spectrophotometry of H Ly Alpha Emission from the Local Interstellar Medium’,Astron. Astrophys. 139, 389.Google Scholar
  50. Cleary, M. N., Heiles, C., and Haslam, C. G. T.: 1979, ‘A Synoptic View of the Galaxy in HI’,Astron. Astrophys. Suppl. Ser. 40, 47–50.Google Scholar
  51. Colomb, F. R., Poppel, W. G. L., and Heiles, C.: 1980,Astron. Astrophys. Suppl Ser. 40, 47–50.Google Scholar
  52. Cordes, J., Rickett, B., and Backer, D.: 1988, ‘Radio Wave Scattering in the Interstellar Medium’,AIP Conf. Proc. 174.Google Scholar
  53. Cox, D. P. and Anderson, P. R.: 1982, ‘Extended Adiabatic Blast Waves and a Model of the Soft X-Ray Background’,Astrophys. J. 253, 268–289.Google Scholar
  54. Cox, D. P. and Reynolds, R. J.: 1987, ‘The Local Interstellar Medium’,Ann. Rev. Astron. Astrophys. 25, 303–344.Google Scholar
  55. Cox, D. P. and Snowden, S. L.: 1986, ‘Perspective on the Local Interstellar Medium’,Adv. Space Res. 6, 97–108.Google Scholar
  56. Cowie, L. L.: 1978, ‘Refractory Grain Destruction in Low-Density Shocks’,Astrophys. J. 225, 887–892.Google Scholar
  57. Cowie, L. L., McKee, C. F., and Ostriker, J. P.: 1981, ‘Supernova Remnant Evolution in an Inhomogeneous Medium I. Numeric Models’,Astrophys. J. 247, 908–924.Google Scholar
  58. Crawford, I. A.: 1991, ‘High-Resolution Observations of Interstellar NaI and Caii Towards the Scorpius Centaurus Association’,Astron. Astrophys. 247, 183–201.Google Scholar
  59. Crawford, I. A.: 1992, ‘High-Resolution Observations of the Interstellar λ3302 NaI Doublet and a Discussion of the Resulting NaI/Caii Ratios’,Monthly Notices Roy. Astron. Soc. 259, 47–62.Google Scholar
  60. Crinklaw, G., Federman, S. R., and Joseph, C. L.: 1993, ‘The Depletion of Calcium in the Interstellar Medium’, preprint.Google Scholar
  61. Crutcher, R. M.: 1982, ‘The Local Interstellar Medium’,Astrophys. J. 254, 82–87.Google Scholar
  62. Cui, W. and Cox, D. P.: 1992, ‘Two-Temperature Models of Old Supernova Remnants with Ion and Electron Thermal Conduction’,Astrophys. J. 401, 206–219.Google Scholar
  63. Cummings, A. C. and Stone, E. C.: 1988, in V. J. Pizzo, T. Holzer, and D. Sime (eds.), ‘Composition, Gradients, and Temporal Variations of the Anomalous Cosmic-Ray Component’,Solar Wind VI Proceedings, National Center for Atmospheric Research, Boulder.Google Scholar
  64. Cummings, A. C. and Stone, E. C.: 1990, ‘Elemental Composition of the Very Local Interstellar Medium as Deduced from Observations of Anomalous Cosmic Rays’,Contributions to the 21 st Int. Cosmic Ray Conf., Adelaide.Google Scholar
  65. Cummings, J. R., Cummings, A. C., Mewaldt, R. A., Selesnic, E. C. Stone, and von Rosenvinge, T. T.: 1993, ‘New Evidence for Anomalous Cosmic Rays Trapped in the Magnetosphere’, paper SH6.2,23rd Int. Cosmic Ray Conf., Calgary, Canada.Google Scholar
  66. Davelaar, J., Bleeker, J. A. M., and Deerenberg, A. J. M.: 1980, ‘X-Ray Characteristics of Loop I and the Local Interstellar Medium’,Astron. Astrophys. 92, 231–237.Google Scholar
  67. De Boer, K. S., Lenhart, H., van der Hucht, K. A., Kamperman, T. M., Kondo, Y., and Bruhweiler, F. C.: 1986, ‘Interstellar Absorption Lines between 2000 and 3000 A in Nearby Stars’,Astron. Astrophys. 157, 119–128.Google Scholar
  68. De Geus, E. J.: 1991, ‘Interaction of Stars and Interstellar Matter in Scorpio Centaurus’,Astron. Astrophys. 262, 258–270.Google Scholar
  69. Devereux, N. A. and Young, J. S.: 1990, ‘The Gas/Dust Ratio in Spiral Galaxies’,Astrophys. J. 359, 42–55.Google Scholar
  70. Diamond, P. J., Goss, W. M., Romney, J. D., Booth, R. S., Kalberia, P. M. W., and Mebold, U.: 1989, ‘Structure of the Interstellar Medium at the 25 AU Scale’,Astrophys. J. 347, 302.Google Scholar
  71. Dieter, N., Welch, W. J., and Romney, J. D.: 1976, ‘A Very Small Interstellar Neutral H Cloud Observed with VLBI Techniques’,Astrophys. J. 206,L113-L117.Google Scholar
  72. Diplas, A. and Savage, B. D.: 1993, ‘An IUE Survey of Interstellar HI Lyα Absorption. II. Interpretations’,Astrophys.J., in press.Google Scholar
  73. Duley, W. W.: 1978, ‘Magnetic Alignment of Interstellar Grains’,Astrophys. J. 219, L129-L132.Google Scholar
  74. Dunn, G. H.: 1992, in W. G. Graham, W. Fritsche, Y. Hahn, and J. A. Tanis (eds.), ‘Early Dielectronic Recombination Measurements: Singly Charged Ions’,Recombination of Atomic Ions, Plenum Press, New York.Google Scholar
  75. Dupree, A. K. and Raymond, J. C.: 1982, ‘Discovery of Highly Ionized Species in the Ultraviolet Spectrum of Feige 24’,Astrophys. J. 263, L63.Google Scholar
  76. Dupree, A. K., Baliunas, S. L., and Shipman, H. L.: 1977, ‘Deuterium and Hydrogen in the Local Interstellar Medium’,Astrophys. J. 218, 361.Google Scholar
  77. Edgar, R. J., and Cox, D. P.: 1993, ‘Hot Bubbles in a Magnetic Interstellar Medium: Another Look at the Soft X-Ray Background’,Astrophys. J. 413, 190–197.Google Scholar
  78. Evans, R. G., Jordan, C., and Wilson, R.: 1975, ‘Ultraviolet Emission Lines in the Spectrum of Procyon’,Nature 253, 612.Google Scholar
  79. Fahr, H. J.: 1971, ‘Interplanetary Hydrogen Cone and Its Solar Cycle Variations’,Astron. Astrophys. 14, 263–274.Google Scholar
  80. Fahr, H. J. and Scherer, K.: 1990, ‘Heliospheric Neutral Gases in the Three-Dimensional and Time-Dependent Solar Force and Ionization Fields’,Astron. Astrophys. 232, 556–564.Google Scholar
  81. Ferlet, R., Lallement, R., and Vidal-Madjar, A.: 1986, ‘The Local Interstellar Medium over 5 pc in the Direction of α Aquilae’,Astron. Astrophys. 163, 204–209.Google Scholar
  82. Ferlet, R., Vidal-Madjar, A., and Gry, C.: 1985, ‘NaI as a Tracer of HI in the Diffuse Interstellar Medium’,Astrophys. J. 298, 838–843.Google Scholar
  83. Ferrara, A.: 1993, ‘On Turbulence Decay in the Local Bubble and Its Implications for the Galactic ISM’,Astrophys. J., submitted.Google Scholar
  84. Ferriere, K. M., MacLow, M.-M., and Zweibel, E. G.: 1991, ‘Expansion of a Superbubble in a Uniform Magnetic Field’,Astrophys.J. 375, 239–253.Google Scholar
  85. Finley, D. S. and Kimble, R. A.: 1994, ‘EUV Spectra of Hot DA White Dwarfs’,183rd Astron. Astrophys. Meeting, Washington, D.C.Google Scholar
  86. Finley, D. S., Jelinsky, P., Dupuis, J., and Koester, D.: 1993, ‘Initial White Dwarf Results from the Extreme Ultraviolet Explorer’,Astrophys. J. 417, 259–264.Google Scholar
  87. Frail, D. A., Cordes, J. M., Hankins, T. H., and Weisberg, J. M.: 1991, ‘HI Absorption Measurements toward 15 Pulsars and the Radial Distribution of Diffuse Ionized Gas in the Galaxy’,Astrophys. J. 382, 168–181.Google Scholar
  88. Frisch, P. C.: 1973, private letter to G. Munch.Google Scholar
  89. Frisch, P. C.: 1980, ‘The Interstellar Material in Front of χ Ophiuchus. II. Ultraviolet Observations’,Astrophys. J. 241, 697–708.Google Scholar
  90. Frisch, P. C.: 1981, ‘The Nearby Interstellar Medium’,Nature 293, 377–379.Google Scholar
  91. Frisch, P. C.: 1986, ‘The Physical Properties of the “Local Fluff'’,Adv. Space Res. 6, 345–352.Google Scholar
  92. Frisch, P. C.: 1990, in S. Grzedzielski and E. Page (eds.), ‘Characteristics of the Local Interstellar Medium’,COSPAR Colloquia Series, No. 1, Physics of the Outer Heliosphere, Pergamon Press, London, pp. 19–21.Google Scholar
  93. Frisch, P. C.: 1993a, ‘Whence Geminga?’,Nature 364, 395–396.Google Scholar
  94. Frisch, P. C.: 1993b, ‘G-Star Astropauses: A Test for Interstellar Pressure’,Astrophys. J. 407, 198–212.Google Scholar
  95. Frisch, P. C.: 1994, ‘Morphology and Ionization of the Interstellar Cloud Surrounding the Solar System’,Science, in press (September).Google Scholar
  96. Frisch, P. C. and York, D. G.: 1983, ‘Synthesis Maps of Ultraviolet Observations of Neutral Interstellar Gas’,Astrophys. J. 271, L59-L63.Google Scholar
  97. Frisch, P. C. and York, D. G.: 1986, in R. Smoluchowski, J. N. Bahcall, and M. Matthews (eds.), ‘Interstellar Clouds Near the Sun’,The Galaxy and the Solar System,University of Arizona Press, Tucson, AZ, pp. 83–100.Google Scholar
  98. Frisch, P. C. and York, D. G.: 1990, in R. F. Malinaand S. Bowyer (eds.), ‘The Distribution of Nearby HI and Hii Gas’,Extreme Ultraviolet Astronomy, Pergamon Press, London.Google Scholar
  99. Frisch, P. C., York, D. G., and Fowler, J.: 1987, ‘Local Interstellar Medium. VII. The Local Interstellar Wind and Interstellar Material in Front of the Nearby Star α Ophiuchi’,Astrophys. J. 320, 842–849.Google Scholar
  100. Frisch, P. C., Welty, D. E., York, D. G., and Fowler, J.: 1990a, ‘Ionization in Nearby Interstellar Gas’,Astrophys. J. 357, 514–523.Google Scholar
  101. Frisch, P. C., Sembach, K., and York, D. G.: 1990b, ‘Studies of the Local Interstellar Medium. VIII. Morphology and Kinematics of the Diffuse Interstellar Clouds toward Orion’,Astrophys. J. 364, 540–548.Google Scholar
  102. Frisch, P. C., Slojkowski, S. E., Rodriguez-Bell, T., and York, D.: 1993, ‘Model Atmospheres: Tool for Identifying Interstellar Features’,Astrophys. J. Suppl. Ser. 84, 55–70.Google Scholar
  103. Frisch, P. C., Welty, D. E., and York, D. G.: 1994, ‘IUE Observations of Nearby Interstellar Matter’, in preparation.Google Scholar
  104. Frogel, J. A. and Stothers, R.: 1977, ‘Local Complex of O and B Stars’,Astron. J. 82, 890–901.Google Scholar
  105. Garcia-Munoz, M., Mason, G. M., and Simpson, J. A.: 1973, ‘A New Test for Solar Modulation Theory: The 1972 May–July Low-Energy Galactic Cosmic-Ray Proton and Helium Spectra’,Astrophys. J. 182, L81-L84.Google Scholar
  106. Garmire, G. P., Nousek, J. A., Apparao, K. M. V., Burrows, D. N., Fink, R. L., and Kraft, R. P.: 1992, ‘The Soft X-Ray Diffuse Background Observed with the HEAO 1 Low-Energy Detectors’,Astrophys. J. 399, 694–703.Google Scholar
  107. Gehrels, N. and Chen, W.: 1993, ‘The Geminga Supernova as a Possible Cause of the Local Interstellar Bubble’,Nature 361, 706–707.Google Scholar
  108. Genova, R., Molaro, P., Vladilo, G., and Beckman, J. E.: 1990, ‘Mgii Observed in the Local Interstellar Medium: The Local Cloud’,Astrophys. J. 355, 150–158.Google Scholar
  109. Gloeckler, G., Geiss, J., Balsiger, H., Fisk, L. A., Galvin, A. B., Ipavich, F. M., Ogilvie, K. W., von Steiger, R., and Wilken, B.: 1993, ‘Detection of Interstellar Pick-up Hydrogen in the Solar System’,Science 261, 70.Google Scholar
  110. Goulet, T.: 1984, ‘Kinematics of Gas and Stars in the Solar Neighborhood’, M.S. Thesis, Department of Physics, University of British Columbia.Google Scholar
  111. Green, J. C., Jelinksky, P. J., and Bowyer, S.: 1990, ‘The Extreme Ultraviolet Spectrum of G1912-B2B and the Ionization of the Local Interstellar Medium’,Astrophys. J. 359, 499.Google Scholar
  112. Grun, E., Zook, H. A., Baguhl, M. et al.: 1992, ‘Ulysses Dust Measurements Near Jupiter’,Science 257, 1550–1552.Google Scholar
  113. Grun, E., Zook, H. A., Baguhl, M. et al.: 1993, ‘Discovery of Jovian Dust Streams and Interstellar Grains by the Ulysses Spacecraft’,Nature 362, 428–430.Google Scholar
  114. Gruntman, M. A.: 1989, ‘Solar Flare Effects on Neutral Gas Glow in Interplanetary Space’,Planetary Space Sci. 37, 369–377.Google Scholar
  115. Gruntman, M. A.: 1993, ‘A New Technique forin situ Measurement of the Composition of Neutral Gas in Interplanetary Space’,Planetary Space Sci. 41, 307–319.Google Scholar
  116. gry, C., York, D. G., and Vidal-Madjar, A.: 1985, ‘The Exceptionally Vacant Line of Sight to Beta Canis Majoris’,Astrophys. J. 296, 593–599.Google Scholar
  117. Gurnett, D. A., Kurth, W. S., Allendorf, S. C., and Poynter, L. R.: 1993, ‘Radio Emission from the Heliopause Triggered by an Interplanetary Shock’,Science 262, 199–203.Google Scholar
  118. Hamdy, M. A., Abo Elazm, M. S., and Saad, S. M.: 1993, ‘Spectrophotometric Studies of Two Be Stars, Alpha Leo and 17 Tau. Comment: The Comparison Star CANNOT BE HD 79917, but is Most Likely HD 79913’,Astrophys. Space Sci. 202, 315–325.Google Scholar
  119. Harris, A. W., Gry, C., and Bromage, G. W.: 1984, ‘Correlation of Interstellar Element Depletions with Mean Gas Density’,Astrophys. J. 284, 157–162.Google Scholar
  120. Hayakawa, S., Kato, T., Nagase, F., Yamashita, K., and Tanaka, K.: 1978, ‘Distribution and Energy Spectrum of Diffuse Soft X-Rays’,Astron. Astrophys. 62, 21–28.Google Scholar
  121. Heiles, C. and Habing, H. J.: 1974, ‘A Complete Survey of 21 cm Line Radiation for |b|>100. I. Atlas of Almost Contour Maps’,Astron. Astrophys. Suppl. Ser. 14, 1–556.Google Scholar
  122. Herbig, G. H.: 1968, ‘The Interstellar Line Spectrum of Zeta Ophiuchi’,Z. f. Astrophys. 68, 243–277.Google Scholar
  123. Hobbs, L. M. and Welty, D. E.: 1991, ‘The InterstellarD 1 Line at High Resolution’,Astrophys. J. 368, 426.Google Scholar
  124. Hobbs, L. M., Blitz, L., Penprase, B. E., Magnani, L., and Welty, D. E.: 1988, ‘On the Nearest Molecular Clouds. II. MBM 12 and 16’,Astrophys. J. 327, 356–363.Google Scholar
  125. Hoffleit, D. and Warren, W.: 1991,The Bright Star Catalog, 5th Rev. ed., Selected Astronomical Catalogs, Volume 1, NASA, Astronomical Data Center.Google Scholar
  126. Holzer, T. E.: 1977, ‘Neutral Hydrogen in Interplanetary Space’,Rev. Geophys. Space Phys. 15, 467–489.Google Scholar
  127. Holzer, T. E.: 1989, ‘Interaction Between the Solar Wind and the Interstellar Medium’,Ann. Rev. Astron. Astrophys. 27, 199–234.Google Scholar
  128. Holzer, T. E., Mewaldt, R. A., and Neugebauer, M.: 1990, ‘Collected Papers from Interstellar Probe Workshop’, held in Ballston, Virginia, March 20–21, 1990.Google Scholar
  129. Innes, D. E. and Hartquist, T. W.: 1984, ‘Are We in an Old Superbubble?’,Monthly Notices Roy. Astron. Soc. 209, 7–13.Google Scholar
  130. Iwan, D. C.: 1980, ‘X-Ray Observations of the North Polar Spur’,Astrophys. J. 239, 316–327.Google Scholar
  131. Jacobs, V. L., Davis, J., Rogerson, J. E., and Blaha, M.: 1979, ‘Dielectronic Recombination Rates, Ionization Equilibrium, and Radiative Energy-Loss Rates for Neon, Magnesium and Sulfur Ions in Low-Density Plasmas’,Astrophys. J. 230, 627–638.Google Scholar
  132. Jakobsen, P.: 1991, in R. F. Malina and S. Bowyer (eds.),Extreme Ultraviolet Astronomy, Pergamon Press, London, pp. 281–291.Google Scholar
  133. Jenkins, E. B. and Shaya, E. J.: 1979, ‘Survey of Interstellar Ci: Abundances and Pressures in the ISM’,Astrophys. J. 231, 55–72.Google Scholar
  134. Jenkins, E. B.: 1987, in D. J. Hollenbach and H. A. Thronson, Jr., ‘Element Abundances in the Interstellar Atomic Material’,Interstellar Processes, D. Reidel Publ. Co., Dordrecht, Holland, pp. 533–560.Google Scholar
  135. Jokipii, J. R.: 1991, in S. Grzedzielski and E. page (eds.), ‘Anomalous Component of Cosmic Rays’,Physics of the Outer Heliosphere, COSPAR Colloq. Series 1, 169.Google Scholar
  136. Jones, D. H. P.: 1971, ‘Kinematics of the Scorpio-Centaurus Association and Gould's Belt’,Monthly Notices Roy. Astron. Soc. 152, 231–259.Google Scholar
  137. Joseph, C. L.: 1993,Additional Constraints on the Spitzer Interstellar Depletion Model 275, 597–601.Google Scholar
  138. Juda, M., Bloch, J. J., Edwards, B. C., McCammon, D., Sanders, W. T., Snowden, S. L., and Zhang, J.: 1991, ‘Limits on the Density of Neutral Gas within 100 Parsecs from Observations of the Soft X-ray Background’,Astrophys. J. 367, 182.Google Scholar
  139. Kashyap, V., Rosner, R., Micela, G., Sciortino, S., Vaiana, G. S., Harnden, F. R., Jr.: 1992, ‘Modeling the Stellar Contribution to the Galactic Component of the Diffuse Soft X-Ray Background. I. Background Fluxes and Number Counts’,Astrophys. J. 391 667.Google Scholar
  140. Kimble, R. A., Davidsen, A. F., Blair, W. P., Bowers, C. W., Dixon, W. V., Durrance, S. T., Feldman, P. D., Ferguson, H. C., Henry, R. C., Kriss, G. A., Druk, J. W., Long, K. S., Moos, H. W., and Vancura, O.: 1993a, ‘Extreme Ultraviolet Observations of G191-B2B and the Local Interstellar Medium with the Hopkins Ultraviolet Telescope’,Astrophys. J. 404, 663.Google Scholar
  141. Kimble, R. A., Davidsen, A. F., Long, K. S., and Feldman, P. D.: 1993, ‘Extreme Ultraviolet Observations of HZ43 and the Local H/He Ratio with the Hopkins Ultraviolet Telescope’,Astrophys. J. 408, L41-L44.Google Scholar
  142. Kondo, Y., Talent, D. L., Barker, E. S., Dufour, R. J., and Modisette, J. L.: 1978, ‘On the Column Densities of Interstellar Mg+ to Sirius and Other Nearby Stars’,Astrophys. J. 220, L97-L102.Google Scholar
  143. Kondo, Y., Bruhweiler, F. C., and Savage, B. D.: 1984, ‘Local Interstellar Medium’,IAU Colloq. 81, 39–96.Google Scholar
  144. Kulkarni, S. R. and Fich, M.: 1985, ‘The Fraction of High Velocity Dispersion Hi in the Galaxy’,Astrophys. J. 289, 792–802.Google Scholar
  145. Kulkarni, S. R. and Heiles, C.: 1987, in D. J. Hollenbach and H. A. Thronson, Jr., ‘The Atomic Component’,Interstellar Processes, pp. 87–122.Google Scholar
  146. Kurth, W. S. and Gurnett, D. A.: 1993, ‘Plasma Waves as Indicators of the Termination Shock’,J. Geophys. Res. 98, 15, 129–15, 136.Google Scholar
  147. Lallement, R.: 1993, ‘Measurements of the Interstellar Gas’,Adv. Space Res. 13, 113–120.Google Scholar
  148. Lallement, R.: 1990, in S. Grzedzielski and E. Page (eds.), ‘Scattering of Solar UV on Local Neutral Gases’,COSPAR Colloquia Series, No. 1, Physics of the Outer Heliosphere, Pergamon Press, London, pp. 49–60.Google Scholar
  149. Lallement, R. and Bertin, P.: 1992, ‘Northern-Hemisphere Observations of Nearby Interstellar Gas: Possible Detection of the Local Could’,Astron. Astrophys. 266, 479.Google Scholar
  150. Lallement, R., Vidal-Madjar, A., and Ferlet, R.: 1986, ‘Multi-Component Velocity Structure of the Local Interstellar Medium’,Astron. Astrophys. 168, 225–236.Google Scholar
  151. Lallement, R., Bertaux, J. L., Chassefiere, E., and Sandel, B.: 1991, ‘Interplanetary Lyman-Alpha Observations with UVS on Voyager’,Astron. Astrophys. 252, 385–401.Google Scholar
  152. Lallement, R., Malama, Y. G., Quemerais, E., Bertaux, J. L., and Zaitsev, N. A.: 1992, ‘Interplanetary Lyman-Alpha Spectra as a Diagnostic of the Local Interstellar Plasma Density: The Baranov Two-Shocks Heliosphere Case’,Astrophys. J. 396, 696.Google Scholar
  153. Lallement, R., Bertaux, J.-L., and Clarke, J. T.: 1993a, ‘Deceleration of Interstellar Hydrogen at the Heliospheric Interface’,Science 260, 1095–1098.Google Scholar
  154. Lallement, R., Bertin, P., Ferlet, R., Vidal-Madjar, A., and Bertaux, J. L.: 1993b, ‘Interstellar Clouds toward Sirius and Local Cloud Ionization’,Astron. Astrophys., in press.Google Scholar
  155. Landsman, W. B., Murthy, J., Henry, R. C., Moos, H. W., Linsky, J. L., and Russell, J. L.: 1986, ‘IUE Observations of Interstellar Hydrogen and Deuterium toward Alpha Cen B’,Astrophys. J. 303, 791.Google Scholar
  156. Landsman, W. B. and Simon, T.: 1993, ‘Stellar Lyman-Alpha Emission and the Local Interstellar Medium’,Astrophys. J. 366, L79-L82.Google Scholar
  157. Landsman, W. B., Henry, R. C., Moos, H. W., and Linsky, J. L.: 1984, ‘Observation of Interstellar Hydrogen and Deuterium toward Alpha Centauri A’,Astrophys. J. 285, 801.Google Scholar
  158. Landini, M. and Fossi, B. C.: 1990, ‘The X-UV Spectrum of Thin Plasmas’,Astron. Astrophys. Suppl. Ser. 82, 229–260.Google Scholar
  159. Lazio, T. J., Spangler, S. R., and Cordes, J. M.: 1990, ‘Faraday Rotation Measure Variations in the Cygnus Region and the Spectrum of Interstellar Turbulence’,Astrophys. J. 363, 515–527.Google Scholar
  160. Leroy, J. L.: 1993, ‘A Polarimetric Investigation on Interstellar Dust within 50 pc from the Sun’,Astron. Astrophys. 274, 203–213.Google Scholar
  161. Lieu, R., Sumner, T. J., Bowyer, S., and Sidher, S. D.: 1993, ‘Discovery of a Shadow in the Diffuse EUV Background’,Astrophys. J., in press.Google Scholar
  162. Lieu, R., Quenby, J. J., Sidher, S. D., Sumner, T. J., Willingale, R., West, R. G., Harris, A. W., Snowden, S. L., and Bickert, K.: 1992, ‘Rosat Wide Field Camera Minisurvey of the Diffuse Sky Bacground in 90–188 eV Soft X-Rays’,Astrophys. J. 397, 158–164.Google Scholar
  163. Lilienthal, D. and de Boer, K. S.: 1991, ‘Location and Thickness of the Nearest Neutral Gas Cloud in the Direction of Auriga-Perseus’,Astron. Astrophys. Suppl. Ser. 87, 471–479.Google Scholar
  164. Linsky, J. L., Brown, A., Gayley, K., Diplas, A., Savage, B. D., Ayres, T. R., Landsman, W., Shore, S. N., and Heap, S. R.: 1993, ‘GHRS Observations of the Local Interstellar Medium and the Deuterium/Hydrogen Ratio Along the Line of Sight toward Capella’,Astrophys. J. 402, 694–709.Google Scholar
  165. Linsky, J. L., Diplas, A., Ayres, T., Wood, B., and Brown, A.: 1994, ‘A Reanalysis of the Interstellar Medium Along the Capella Line of Sight’,183rd American Astronomical Society Meeting, Washington, D.C.Google Scholar
  166. Lucke, P. B.: 1978, ‘Distribution of Color Excesses and Interstellar Reddening Material in the Solar Neighbourhood’,Astron. Astrophys. 64, 367–377.Google Scholar
  167. MacLow, M.-M. and McCray, R.: 1988, ‘Superbubbles in Disk Galaxies’,Astrophys. J. 324, 776–785.Google Scholar
  168. Martin, E. R.: 1981, ‘Components in the Interstellar Medium’, Ph.D. Dissertation, Princeton University.Google Scholar
  169. Mathis, J. S.: 1986, ‘The Alignment of Interstellar Grains’,Astrophys. J. 308, 281.Google Scholar
  170. Mathis, J. S.: 1990, ‘Interstellar Dust and Extinction’,Ann. Rev. Astron. Astrophys. 28, 37–70.Google Scholar
  171. Mathis, J. S., Rumpl, W., and Nordsieck, K. H.: 1977, ‘The Sized Distribution of Interstellar Grains’,Astrophys. J. 217, 425.Google Scholar
  172. McCammon, D. and Sanders, W. T.: 1990, ‘The Soft X-Ray Background and Its Origins’,Ann. Rev. Astron. Astrophys. 28, 657–688.Google Scholar
  173. McClintock, W., Henry, R. C., Linsky, J. L., and Moos, W. H.: 1978, ‘Ultraviolet Observations of Cool Stars. VII. Local Interstellar Hydrogen and Deuterium Lyman α’,Astrophys. J. 225, 465–481.Google Scholar
  174. McCray, R. and Kafatos, M. C.: 1987, ‘Supershells and Propagating Star Formation’,Astrophys. J. 317, 190–196.Google Scholar
  175. McKee, C. and Cowie, J. L.: 1977, ‘The Evaporation of Spherical Clouds in a Hot Gas. II. Effects of Radiation’,Astrophys. J. 215, 213–225.Google Scholar
  176. McKee, C. and Ostriker, J. P.: 1977, ‘Theory of the Interstellar Medium: Three Components Regulated by Supernova Explosions in an Inhomogeneous Substrate’,Astrophys. J. 218, 148–169.Google Scholar
  177. Mewaldt, R. A., et al.: 1993a, ‘The Return of the Anomalous Cosmic Ray Component to 1 AU in 1992’,Geophys. Res. Letters 20, 2263.Google Scholar
  178. Mewaldt, R. A., Cummings, A. C., Cummings, J. R., Stone, E. C., and von Rosenvinge, T. T.: 1993b, ‘The Return of the Anomalous Cosmic Ray Component to 1 AU in 1992’, paper SH6.1,23rd Int. Cosmic Ray Conf., Calgary, Canada.Google Scholar
  179. Micela, G., Harnden, F. R., Rosner, R., Sciortino, S., and Vaiana, G. S. P.: 1991, ‘The Diffuse Soft X-Ray Background as Seen with the Einstein Observatory’,Astrophys. J. 380, 495–510.Google Scholar
  180. Mihalas, D. and Binney, J.: 1981,Galactic Astronomy: Structure and Kinematics, W. H. Freeman and Co., san Francisco, p. 398.Google Scholar
  181. Miller, W. W. and Cox, D. P. 1993, ‘The Diffuse Ionized Interstellar Medium: Structures Resulting from Ionization by O Stars’,Astrophys. J. 417, 579–594.Google Scholar
  182. Mobius, E., Hovestadt, D., Klecker, B., Scholer, M., Gloeckler, G., and Ipavich, F. M.: 1985, ‘Direct Observation of Heii Pick-up Ions of Interstellar Origin in the Solar Wind’,Nature 318, 426–429.Google Scholar
  183. Mobius, E., Klecker, B., Hovestadt, D., and Scholer, M.: 1988, ‘Interaction of Interstellar Pick-up Ions with the Solar Wind’,Astron. Space Sci. 144, 487.Google Scholar
  184. Morton, D. C.: 1991, ‘Atomic Data for Resonance Absorption Lines. I. Wavelengths Longward of the Lyman Limit’,Astrophys. J. Suppl. Ser. 77, 119–202.Google Scholar
  185. Munch, G. and Unsold, A.: 1962, ‘Interstellar Gas Near the Sun’,Astrophys. J. 135, 711–714.Google Scholar
  186. Murray, M. J., Dufton, P. L., Hibbert, A., and York, D. G.: 1984, ‘Interstellar Magnesium Abundances’,Astrophys. J. 282, 481–484.Google Scholar
  187. Murthy, J., Henry, R. C., Moos, H. W., Landsman, W. B., Linsky, J. L., Vidal-Madjar, A., and Gry, C.: 1987, ‘IUE Observations of Hydrogen and Deuterium in the Local Interstellar Medium’,Astrophys. J. 315, 675.Google Scholar
  188. Murthy, J., Wofford, J. B., Henry, R. C., Moos, W. H., Vidal-Madjar, A., Linsky, J. L., and Gry, C.: 1989, ‘IUE Observations of the Interstellar Medium toward Beta Geminorum’,Astrophys. J. 336, 949–953.Google Scholar
  189. Murthy, J., Henry, R. C., Moos, H. W., Vidal-Madjar A., Linsky, J. L., and Gry, C.: 1990, ‘IUE Observations of Hydrogen and Deuterium in the Local Interstellar Medium’,Astrophys. J. 356, 223.Google Scholar
  190. Nussbaumer, H. and Storey, P. J.: 1986, ‘Dielectronic Recombination at Low Temperatures. III. Recombination Coefficients for Mg, Al, Si’,Astron. Astrophys. Suppl. Ser. 64, 545–555.Google Scholar
  191. Paresce, F.: 1984, ‘On the Distribution of Interstellar Matter Around the Sun’,Astron. J. 89, 1022–1037.Google Scholar
  192. Paerels, F. B. S. and Heise, J.: 1989, ‘A Soft X-Ray Survey of Hot White Dwarfs with EXOSAT’,Astrophys. J. 339, 1000–1012.Google Scholar
  193. Parker, E. N.: 1992, ‘Fast Dynamos, Cosmic Rays, and the Galactic Magnetic Field’,Astrophys. J. 401, 137–146.Google Scholar
  194. Pequignot, D. and Aldrovandi, S. M. V.: 1986, ‘The Ionization Balance inHi Regions’,Astron. Astrophys. 161, 169–176.Google Scholar
  195. Perry, C. L. and Johnston, L.: 1982, ‘Photometric Map of Interstellar Redding within 300 Parsecs’,Astrophys. J. Suppl. Ser. 50, 451–516.Google Scholar
  196. Perry, C. L., Johnston, L., and Crawford, P. L.: 1983, ‘Photometric Map of Interstellar Reddening within 100 Parsecs’, preprint.Google Scholar
  197. Phillips, J. A. and Wolszczan, A.: 1991, “Time Variability of Pulsar Dispersion Measures’,Astrophys. J. 382, L27-L30.Google Scholar
  198. Pounds, K. A., Allan, D. J., Barber, C. et al.: 1993, ‘The Rosat Wide Field Camera All-Sky Survey of Extreme Ultraviolet Sources’,Monthly Notices Roy. Astron. Soc. 260, 77–102.Google Scholar
  199. Puget, J. L. and Leger, A.: 1989, ‘A New Component of the Interstellar Matter: Small Grains and Large Aromatic Molecules’,Ann. Rev. Astron. Astrophys. 27, 161–198.Google Scholar
  200. Rand, R. J. and Kulkarni, S. R.: 1989, ‘Local Galactic Magnetic Field’,Astrophys. J. 343, 760–772.Google Scholar
  201. Rand, R. J. and Lyne, A. G.: 1993, ‘New Rotation Measures of Distant Pulsars in the Inner Galaxy and Magnetic Field Reversals’,Monthly Notices Roy. Astron. Soc., submitted.Google Scholar
  202. Reynolds, R. J.: 1990, in S. Grzedzielski and E. Page (eds.), ‘Lower Limit on the Ionization Fraction of the Very Local Interstellar Medium’,COSPAR Colloquia Series, No. 1, Physics of the Outer Heliosphere, pp. 101–104.Google Scholar
  203. Reynolds, R. J.: 1992a, in J. Cassinelli and E. Churchwell (eds.), ‘The Radiative Ionization of the Interstellar Medium — The Warm Ionized Gas’,Massive Stars: Their Lives in the Interstellar Medium.Google Scholar
  204. Reynolds, R. J.: 1992b, ‘The Warm Ionized Medium’,Back to the Galaxy.Google Scholar
  205. Ripkin, H. W. and Fahr, H. J.: 1983, ‘Modification of the Local Interstellar Gas Properties in the Heliospheric Interface’,Astron. Astrophys. 122, 181–192.Google Scholar
  206. Rogerson, J. B., York, D. G., Drake, J. F., Jenkins, E. B., Morton, D. C., and Spitzer, L.: 1973, ‘Spectroscopic results from the Copernicus Satellite. III. Ionization and Composition of the Intercloud Medium’,Astrophys. J. 181, L110.Google Scholar
  207. Rucinski, D. and Fahr, H. J.: 1989, ‘Influence of Electron Impact Ionization on the Distribution of Interstellar Helium in the Inner Heliosphere’,Astron. Astrophys. 224, 290–298.Google Scholar
  208. Rumph, T. R., Bowyer, S., and Vennes, S.: 1994, ‘Interstellar Medium Continuum, Autoionization, and Line Absorption in the Extreme Ultraviolet’,Astron. J., in press.Google Scholar
  209. Sancisi, R.: 1974, in F. J. Kerr and S. C. Simonson, III (eds.), ‘Expanding Shells of Neutral Hydrogen as Birthplaces of Stellar Associations’,Galactic Radio Astronomy, pp. 115–128.Google Scholar
  210. Sanders, W. T., Kraushaar, W. L., Nousek, J. A., and Fried, P. M.: 1977, ‘Soft Diffuse X-Rays in the Southern Galactic Hemisphere’,Astrophys. J. 217, L87-L91.Google Scholar
  211. Savage, B. D. and Bohlin, R. C.: 1979, ‘Depletion of Interstellar Gaseous Iron’,Astrophys. J. 229, 136.Google Scholar
  212. Savage, B. D., Cardelli, J. A., and Sofia, U. J.: 1992, ‘Ultraviolet Observations of the Gas Phase Abundances in the Diffuse Clouds Toward ζ Ophiuchi at 3.5 km s−1 Resolution’,Astrophys. J. 401, 706–723.Google Scholar
  213. Scalo, J. M.: 1987, in D. J. Hollenbach and H. A. Thronson, Jr., ‘Theoretical Approaches to Interstellar Turbulence’,Interstellar Processes, pp. 349–396.Google Scholar
  214. Seab, C. G.: 1987, in D. J. Hollenbach and H. A. Thronson, Jr. (eds.), ‘Grain Destruction, Formation, and Evolution’,Interstellar Processes.Google Scholar
  215. Shull, J. M., York, D. G., and Hobbs, L. M.: 1977, ‘Abundance Variations in High-Velocity Interstellar Gas’,Astrophys. J. 211, L139-L143.Google Scholar
  216. Shull, J. M. and van Steenberg, M.: 1982, ‘Ionization Equilibrium of Astrophysically Abundant Elements’,Astrophys. J. Suppl. Ser. 48, 95–107.Google Scholar
  217. Slavin, J. D.: 1989, ‘Consequences of a Conductive Boundary on the Local Cloud. I. No Dust’,Astrophys. J. 392, 718–727.Google Scholar
  218. Slavin, J. D. and Cox, D. P.: 1992, ‘Completing the Evolution of Supernova Remmants and their Bubbles’,Astrophys. J. 392, 131–144.Google Scholar
  219. Slavin, J. D. and Cox, D. P.: 1993, ‘Evolution of Supernova Remnant Bubbles in a Warm Diffuse Medium: Survey of Results from 1D Models and their Impact on Estimates of Interstellar Porosity’,Astrophys. J., in press.Google Scholar
  220. Smith, V. V., Cunha, K., and Plez, B.: 1993, ‘Is Geminga a Runaway Member of the Orion Association?’,Astron. Astrophys. 281, L41-L44.Google Scholar
  221. Snowden, S. L. and Freyberg, M. J.: 1993, ‘The Scattered Solar X-Ray Background of the ROSAT PSPC’,Astrophys. J. 404, 403–411.Google Scholar
  222. Snowden, S. L., Cox, D. P., McCammon, D., and Sanders, W. T.: 1990a, ‘A Model for the Distribution of Material Generating the Soft X-Ray Backgroun’,Astrophys. J. 354, 211–219.Google Scholar
  223. Snowden, S. L., Schmitt, J., and Edwards, B.: 1990b, ‘A Color Gradient in the Soft X-ray Diffuse Background’,Astrophys. J. 364, 118–122.Google Scholar
  224. Snowden, S. L., Mebold, U., Hirth, W., Herbstmeier, U., and Schmitt, J. H. M.: 1991,Science 252, 1529.Google Scholar
  225. Snowden, S. L., MaCammon, D., and Verter, F.: 1993, ‘The X-Ray Shadow of the High-Latitude Molecular Cloud MBM 12’,Astrophys. J. 409, L21-L24.Google Scholar
  226. Snowden, S. L., Hasinger, G., Jahoda, K., Lockman, F. J., McCammon, D., and Sanders, W. T.: 1994, ‘Soft X-Ray and Hi Surveys of the LowN H Region in Ursa Major’,Astrophys. J., August 1.Google Scholar
  227. Sofue, Y. and Reich, W.: 1979, ‘Radio Continuum Observations of the North Polar Spur at 1420 MHz’,Astron. Astrophys. Suppl. Ser 38, 251–263.Google Scholar
  228. Spangler, S. R.: 1991,Astrophys. J. 376, 540.Google Scholar
  229. Spangler, S. R. and Gwinn, C. R.: 1990, ‘Evidence for an Inner Scale to the Density Turbulence in the Interstellar Medium’,Astrophys. J. 353, L29-L32.Google Scholar
  230. Spangler, S. R. and Reynolds, R. J.: 1990, ‘Comparison of H Alpha Intensity and Radio Wave Scattering on Eight Low-Latitude Lines of Sight’,Astrophys. J. 361, 116–120.Google Scholar
  231. Spitzer, L.: 1976, ‘High-Velocity Interstellar Clouds’,Comm. Astrophys. 6, 177–187.Google Scholar
  232. Spitzer, L.: 1978,Physical Processes in the Interstellar Medium, Wiley and Sons, New York.Google Scholar
  233. Stern, S. A., Weintraub, D. A., and Festou, M. C.: 1993, ‘The Discovery of a Beta Pic-like Disk Around the Nearby Star Formalhaut (Alpha PsA)’,Bull. Amer: Astron. Soc. 25, 1124.Google Scholar
  234. Stokes, G. M.: 1978, ‘Interstellar Titanium’,Astrophys. J. Suppl. Ser. 36, 115.Google Scholar
  235. Storey, P. J.: 1981, ‘Dielectric Recombination at Nebular Temperatures’,Monthly Notices Roy. Astron. Soc. 195, 27p-31p.Google Scholar
  236. Stothers, R. and Frogel, J. A.: 1974, ‘Local Complex of O and B Stars. I. Distribution of Stars and Interstellar Dust’,Astron. J. 79, 456–571.Google Scholar
  237. Taylor, J. H. and Cordes, J. M.: 1993, ‘Pulsar Distances and the Galactic Distribution of Free Electrons’,Astrophys. J. 411, 674–684.Google Scholar
  238. Thomas, G. E. and Krassa, R. F.: 1971, ‘OGO5 Measurements of the Lyman Alpha Sky Background’,Astron. Astrophys. 11, 218–233.Google Scholar
  239. Tinbergen, J.: 1982, ‘Interstellar Polarization in the Immediate Solar Neighborhood’,Astron. Astrophys. 105, 53–64.Google Scholar
  240. Vallerga, J. V., Vedder, P. W., Craig, N., and Welsh, B. Y.: 1993a, ‘High-Resolution Caii Observations of the Local Interstellar Medium’,Astrophys. J. 411, 729–749, (V93).Google Scholar
  241. Vallerga, J. V., Vedder, P. W., and Welsh, B. Y.: 1993b, ‘Intense Extreme Ultraviolet Emission from the B Star ∈ CMa’,Astrophys. J. 414, L65-L68.Google Scholar
  242. Vennes, S., Dupuis, J., Rumph, T., Drake, J., and Bowyer, S.: 1993a, ‘The First Detection of Ionized Helium in the Local ISM: EUVE and IUE Spectroscopy of the Hot DA Dwarf GD 246’,Astrophys. J. 410, L119-L122.Google Scholar
  243. Vennes, S., Dupuis, J., Bowyer, S., Fontaine, G., Wiercigroch, A., Jelinsky, P., Wesemael, F., and Malina, R.: 1993b, ‘Low Density of Neutral Hydrogen and Helium in the Local ISM: EUVE Photometry of the Lyman Continuum of the Hot Dwarfs MCT 0501-2858, MCT 0455-2812, HZ 43, and GD 153’,Astrophys. J. 421, L35-L38.Google Scholar
  244. Verschuur, G. L.: 1993, ‘Zeeman Effect Observations of Hi Emission Profiles: Low Field Limits in the Diffuse Interstellar Medium’, preprint.Google Scholar
  245. Vidal-Madjar, A., Laurent, C., Burston, P., and Audouze, P.: 1978, ‘Is the Solar System Entering a Nearby Interstellar Cloud?’,Astrophys. J. 223, 589–600.Google Scholar
  246. Wallis, M. K.: 1975, ‘Local Interstellar Medium’,Nature 254, 202–265.Google Scholar
  247. Wang, Q. D.: 1993, ‘Exploring the Interstellar Medium with X-Ray Shadows’, paper presented at the 1st ROSAT Science Symposium and Data Analysis Workshop.Google Scholar
  248. Warwick, R. S., Barber, C. R., Hodgkin, S. T., and Pye, J. P.: 1993, ‘The EUV Source Population and the Local Bubble’,Monthly Notices Roy. Astron. Soc. 262, 289–300.Google Scholar
  249. Weaver, H.: 1979, in W. B. Burton (ed.), ‘Large Supernova Remnants as Common Features of the Dick’, The Large-Scale Characteristics of the Galaxy, pp. 295–300 (IAU).Google Scholar
  250. Weaver, R., Castor, J., McCray, R., Shapiro, P., and Moore, R.: 1977, ‘Interstellar Bubbles. II. Structure and Evolution’,Astrophys. J. 218, 377–395 (Erratum 1978,220, 742).Google Scholar
  251. Weller, C. S. and Meier, R. R.: 1974, ‘Observations of Helium in the Interplanetary/Interstellar Wind: The Solar-Wake Effect’,Astrophys. J. 193, 471–476.Google Scholar
  252. Welsh, B. Y., Vedder, P. W., Vallerga, J. V., and Craig, N.: 1991, ‘Further High-Resolution Nai Observations of the Local Interstellar Medium’,Astrophys. J. 381, 462.Google Scholar
  253. Welty, D.: 1994, in preparation.Google Scholar
  254. Welty, D., Morton, D. C., and Hobbs, L. M.: 1994, in preparation.Google Scholar
  255. Welty, D. E., Hobbs, L. M., and Kulkarni, V. P.: 1994, ‘High Resolution Survey of Interstellar Nai D1 Lines’,Astrophys. J., submitted.Google Scholar
  256. White, R. L. and Long, K. S.: 1991, ‘Supernova Remnant Evolution in an Interstellar Medium with Evaporating Clouds’,Astrophys. J. 373, 543–555.Google Scholar
  257. Witte, M., Rosenbauer, H., Banaskiewicz, M., and Fahr, H.: 1993, ‘Ulysses Neutral Gas Experiment: Determination of the Velocity and Temperature of the Interstellar Neutral Helium’,Adv. Space Res. 13 (6), 121–130.Google Scholar
  258. York, D. G.: 1976, ‘On the Existence of Molecular Hydrogen along Lines of Sight with Low Reddening’,Astrophys. J. 204, 750.Google Scholar
  259. York, D. G.: 1983, ‘The Interstellar Medium Near the Sun. III. Detailed Analysis of the Line of Sight to Lambda Scorpii’,Astrophys. J. 264, 172–195.Google Scholar
  260. York, D. G. and Rogerson, J. B.: 1976, ‘The Abundance of Deuterium Relative to Hydrogen in Interstellar Space’,Astrophys. J. 203, 378.Google Scholar
  261. York, D. G. and Frisch, P. C.: 1984, in F. Bruhweiler, Y. Kondo, and B. D. Savage (eds.), ‘Synthesis of Data on the Local Interstellar Medium’,Local Interstellar Medium, IAU Colloq.81, 51.Google Scholar
  262. York, D. G. and Kinahan, B. F.: 1979, ‘The Interstellar Medium Near the Sun. II. The Line of Sight to α Virginis’,Astrophys. J. 228, 127–146.Google Scholar
  263. zombeck, M. V.: 1982,Handbook of Space Astronomy and Astrophysics, Cambridge University Press, London.Google Scholar

Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • Priscilla C. Frisch
    • 1
  1. 1.Department of Astronomy and AstrophysicsThe University of ChicagoUSA

Personalised recommendations