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We present a preliminary analysis of the first high-resolution X-ray spectrum of a Seyfert 2 galaxy, Mkn 3, obtained with the High Energy Transmission Grating Spectrometer onboard the Chandra X-ray Observatory. The high-energy spectrum (lambda < 4 Ang) is dominated by reflection of the AGN continuum radiation in a cold optically thick medium and contains bright K-alpha fluorescent lines from iron and silicon, as well as weak, blended lines from sulfur and magnesium. The soft X-ray emission (4 < lambda < 23 Ang) is spatially extended along the [O III] ionization cone and shows discrete signatures of emission following recombination and photoexcitation produced in a warm photoionized region. The measured iron L line fluxes indicate that emission from collisionally ionized plasma is almost completely negligible, and does not contribute significantly to the total energy budget of the X-ray emission. We find that significant fractions of the H- and He-like resonance lines, as well as the observed iron L lines are produced through re-emission from the warm absorbing medium observed in Seyfert 1 galaxies. Its X-ray spectral properties are qualitatively consistent with those of a typical Seyfert 1 galaxy viewed at a different orientation, and provide further convincing evidence for the existence of an obscured Seyfert 1 nucleus in Mkn 3.
We present a preliminary analysis of the 1--10 keV spectrum of the massive X-ray binary Cyg X-3, obtained with the High Energy Transmission Grating Spectrometer on the Chandra X-ray Observatory. The source reveals a richly detailed discrete emission
High resolution spectra of the active binary Capella (G8 III + G1 III) covering the energy range 0.4-8.0 keV (1.5-30 Angstroms) show a large number of emission lines, demonstrating the performance of the HETGS. A preliminary application of plasma dia
We present the first X-ray spectrum obtained by the Low Energy Transmission Grating Spectrometer (LETGS) aboard the Chandra X-ray Observatory. The spectrum is of Capella and covers a wavelength range of 5-175 A (2.5-0.07 keV). The measured wavelength
Details of the design, fabrication, ground and flight calibration of the High Energy Transmission Grating, HETG, on the Chandra X-ray Observatory are presented after five years of flight experience. Specifics include the theory of phased transmission
In an earlier paper, we presented the first evidence for a bow-shock nebula surrounding the X-ray binary LMC X-1 on a scale of ~15 pc, which we argued was powered by a jet associated with an accretion disk. We now present the first evidence for an io