The Compact Uv Nucleus of M 33
نویسندگان
چکیده
The most luminous X-ray source in the Local Group is associated with the nucleus of M33. This source, M33 X-8, appears modulated by ∼ 20% over a ∼ 106 day period, making it unlikely that the combined emission from unresolved sources could explain the otherwise persistent ∼10erg s X-ray flux (Dubus et al. 1997, Hernquist et al. 1991). We present here high resolution UV imaging of the nucleus with the Planetary Camera of the Hubble Space Telescope undertaken in order to search for the counterpart to X-8. The nucleus is bluer and more compact than at longer wavelength images but it is still extended with half of its 3·10 erg s UV luminosity coming from the inner 0. 14. We cannot distinguish between a concentrated blue population and emission from a single object. Subject headings: galaxies: individual (M33) galaxies: nuclei Local Group ultraviolet: stars
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