Observations of the darkest regions in the sky: X-ray shadowing by the Bok globule Barnard 68

Autor(en)

M. J. Freyberg, D. Breitschwerdt, J. Alves

Abstrakt

The densest and closest absorbers of the soft X-ray background (SXRB) in

the Milky Way are Bok globules, located just outside the Local Bubble in

the Pipe Nebula at a distance of 125 pc. With column densities of up to

NH ˜ 1023 cm-2, they are ideal

targets for shadowing the SXRB in the energy range 0.1 - 2 keV, thus

giving important information on the spatial and spectral variation of

the foreground X-ray intensity on small scales. Preliminary analysis of

a recent XMM-Newton EPIC observation of the Bok globule Barnard 68 has

revealed a deep X-ray shadow cast by the globule. The shadow is deepest

at an energy of ˜ 800 eV. Oxygen line emission at ˜ 560 and

˜ 660 eV seems to originate at least partially in the foreground.

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

Max-Planck-Institut für extraterrestrische Physik, European Southern Observatory (Germany)

Journal

Memorie Societa Astronomica Italiana

Band

75

Seiten

509

Publikationsdatum

2004

Peer-reviewed

Ja

Schlagwörter

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