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We have analyzed FUSE (905-1187Å) spectra of a sample of 16 local starburst galaxies. These galaxies cover almost three orders of magnitude in starformation rates and over two orders of magnitude in stellar mass. Absorption features from the stars and interstellar medium are observed in all the spectra. The strongest interstellar absorption features are generally blue-shifted by ∼ 50 to 300 km s −1 , implying the almost ubiquitous presence of starburst-driven galactic winds in this sample. The outflow velocites increase with both the star formation rate and the star formation rate per unit stellar mass, consistent with a galactic wind driven by the population of massive stars. We find outflowing coronal-phase gas (T ∼ 10 5.5 K) detected via the O VI absorption-line in nearly every galaxy. The O VI absorption-line profile is optically-thin, is generally weak near the galaxy systemic velocity, and has a higher mean outflow velocity than seen in the lower ionization lines. The relationship between the line width and column density for the O VI absorbing gas is in good agreement with expectations for radiatively cooling and outflowing gas. Such gas will be created in the interaction of the hot out-rushing wind seen in X-ray emission and cool dense ambient material. O VI emission is not generally detected in our sample, suggesting that radiative cooling by the coronal gas is not dynamically significant in draining energy from galactic winds. We find that the measured outflow velocities in the HI and HII phases of the interstellar gas in a given galaxy increase with the strength (equivalent width) of the absorption feature and not with the -2 -ionization potential of the species. The strong lines often have profiles consisting of a broad and optically-thick component centered near the galaxy systemic velocity and weaker but highly blue-shifted absorption. This suggests that the outflowing gas with high velocity has a lower column density than the more quiescent gas, and can only be readily detected in the strongest absorption lines. From direct observations below the Lyman edge in the galaxy rest-frame, we find no evidence of Lyman continuum radiation escaping from any of the galaxies in the sample. Moreover, the small escape fraction of light in the center of the strong C II absorption feature confirms the high opacity below the Lyman limit in the neutral ISM. The absolute fraction of escaping Lyman continuum photons is typically <1%. This sample provides a unique window on the global properties of local star-forming galaxies as observed in the far-UV and also provides a useful comparison sample for understanding spectra of high redshift star-forming galaxies.

We present images from five observations of the quasar 3C 273 with the Chandra X-Ray Observatory. The jet has at least four distinct features that are not resolved in previous observations. The first knot in the jet (A1) is very bright in X-rays. Its X-ray spectrum is well fitted with a power law with (where a p 0.60 ‫ע‬ 0.05 ). Combining this measurement with lower frequency data shows that a pure synchrotron model can fit Ϫa S ∝ n n the spectrum of this knot from 1.647 GHz to 5 keV (over nine decades in energy) with , similar a p 0.76 ‫ע‬ 0.02 to the X-ray spectral slope. Thus, we place a lower limit on the total power radiated by this knot of 1.5 # ergs s Ϫ1 ; substantially more power may be emitted in the hard X-ray and g-ray bands. Knot A2 is also 43 10 detected and is somewhat blended with knot B1. Synchrotron emission may also explain the X-ray emission, but a spectral bend is required near the optical band. For knots A1 and B1, the X-ray flux dominates the emitted energy. For the remaining optical knots (C through H), localized X-ray enhancements that might correspond to the optical features are not clearly resolved. The position angle of the jet ridge line follows the optical shape with distinct, aperiodic excursions of ‫1ע‬Њ from a median value of Ϫ138Њ .0. Finally, we find X-ray emission from the "inner jet" between 5Љ and 10Љ from the core.

We have analyzed observations with the Chandra X-Ray Observatory of the diffuse emission by hot gas in seven dwarf starburst galaxies, six edge-on starburst galaxies, and nine ultraluminous infrared galaxies. These systems cover ranges of $10 4 in X-ray luminosity, and several thousand in star formation rate and K-band luminosity (a proxy for stellar mass). Despite this range in fundamental parameters, we find that the properties of the diffuse X-ray emission are very similar in all three classes of starburst galaxies. The spectrum of the diffuse emission is well fitted by thermal emission from gas with kT $ 0:25-0.8 keVand with several times solar abundance ratios of -elements to Fe. The ratio of the thermal X-ray to far-infrared luminosity is roughly constant, as is the characteristic surface brightness of the diffuse X-ray emission. The size of the diffuse X-ray source increases systematically with both farinfrared and K-band luminosity. All three classes show strong morphological relationships between the regions of hot gas probed by the diffuse X-ray emission and the warm gas probed by optical line emission. These findings suggest that the same physical mechanism is producing the diffuse X-ray emission in the three types of starbursts. These results are consistent with that mechanism being shocks driven by a galactic ''superwind,'' which is powered by the kinetic energy collectively supplied by stellar winds and supernovae in the starburst.

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