PRESSURE EQUILIBRIUM BETWEEN THE LOCAL INTERSTELLAR CLOUDS AND THE LOCAL HOT BUBBLE

Journal Article · Sun Aug 10 00:00:00 EDT 2014 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/791/1/L14· OSTI ID:22365360

Snowden, S. L.; Chiao, M.; Collier, M. R.; Porter, F. S.; Thomas, N. E. ^[1]; Cravens, T.; Robertson, I. P. ^[2]; Galeazzi, M.; Uprety, Y.; Ursino, E. ^[3]; Koutroumpa, D. ^[4]; Kuntz, K. D. ^[5]; Lallement, R.; Puspitarini, L. ^[6]; Lepri, S. T. ^[7]; McCammon, D.; Morgan, K. ^[8]

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1. NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
2. Department of Physics and Astronomy, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, KS 66045 (United States)
3. Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States)
4. Université Versailles St-Quentin, Sorbonne Universités, UPMC Univ. Paris 06, CNRS/INSU, LATMOS-IPSL, 11 Boulevard d'Alembert, F-78280 Guyancourt (France)
5. The Henry A. Rowland Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD 21218 (United States)
6. GEPI, Observatoire de Paris, CNRS UMR8111, Université Paris Diderot, 5 Place Jules Janssen, F-92190 Meudon (France)
7. University of Michigan, 2455 Hayward Street, Ann Arbor, MI 48109 (United States)
8. Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, WI 53706 (United States)

Three recent results related to the heliosphere and the local interstellar medium (ISM) have provided an improved insight into the distribution and conditions of material in the solar neighborhood. These are the measurement of the magnetic field outside of the heliosphere by Voyager 1, the improved mapping of the three-dimensional structure of neutral material surrounding the Local Cavity using extensive ISM absorption line and reddening data, and a sounding rocket flight which observed the heliospheric helium focusing cone in X-rays and provided a robust estimate of the contribution of solar wind charge exchange emission to the ROSAT All-Sky Survey 1/4 keV band data. Combining these disparate results, we show that the thermal pressure of the plasma in the Local Hot Bubble (LHB) is P/k = 10, 700 cm{sup –3} K. If the LHB is relatively free of a global magnetic field, it can easily be in pressure (thermal plus magnetic field) equilibrium with the local interstellar clouds, eliminating a long-standing discrepancy in models of the local ISM.

• OSTI ID: 22365360
• Journal Information: Astrophysical Journal Letters, Vol. 791, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ABSORPTION
CHARGE EXCHANGE
HELIOSPHERE
HELIUM
INTERSTELLAR SPACE
KEV RANGE
MAGNETIC FIELDS
PLASMA
SOLAR WIND
SOUND WAVES
THREE-DIMENSIONAL CALCULATIONS
VOYAGER SPACE PROBES
X RADIATION