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We report the detection with the Rossi X-Ray Timing Explorer (RXTE) of a Compton reflection signature in the Seyfert galaxy MCG -5-23-16. RXTE also resolves the Fe Kα fluorescence line with FWHM ~48,000 km s-1. This measurement provides the first independent confirmation of ASCA detections in Seyfert galaxies of broad Fe Kα lines that are thought to be the signature of emission from the inner regions of an accretion disk orbiting a black hole. Under the assumption that reflection arises from an isotropic source located above a neutral accretion disk, and using a theoretical model that accounts for the dependence of the reflected spectrum on inclination angle, we derive a 90% confidence range for the disk inclination of i = 50°-81°. The large inclination is consistent with that expected from the unified model for MCG -5-23-16 based on its Seyfert 1.9 classification. If we assume that the high-energy cutoff in the incident spectrum lies at energies larger than a few hundred keV, then the equivalent width of the Fe Kα line is much larger than predicted for the amount of reflection. This implies either an enhanced iron abundance, a covering factor of reflecting material cf > 0.5, or a cutoff in the incident spectrum at energies between ~60 and ~200 keV.

We investigate dusty molecular clouds on the inner edge of the torus which are exposed to the strong ionizing continuum of the active nucleus. The incident ionizing flux pressurizes the cloud and evaporates its outer layers in a wind. The dust grains are sputtered in this hot ( T ≥ 10 6 K) wind. We show that the cloud evaporation time is comparable to the radial drift time of clouds in the torus, but longer than the orbital time. The clouds produce line emission typical of highly ionized gas. Dust opacity prevents the torus line emission from overpowering the broad and narrow line regions, however the torus may be the source of the coronal lines seen in some AGN.

We examine the relative orientation of radio jets and dusty tori surrounding the AGN in powerful radio galaxies at z > 1. The radio core dominance R = P(20 GHz) /P(500 MHz) serves as an orientation indicator, measuring the ratio between the anisotropic Doppler-beamed core extended core emission and the isotropic lobe emission. Assuming a fixed cylindrical geometry for the hot, dusty torus, we derive its inclination i by fitting optically-thick radiative transfer models to spectral energy distributions obtained with the Spitzer Space Telescope. We find a highly significant anti-correlation (p < 0.0001) between R and i in our sample of 35 type 2 AGN combined with a sample of 18 z = 1 3CR sources containing both type 1 and 2 AGN. This analysis provides observational evidence both for the Unified scheme of AGN and for the common assumption that radio jets are in general perpendicular to the plane of the torus. The use of inclinations derived from mid-infrared photometry breaks several degeneracies which have been problematic in earlier analyses. We illustrate this by deriving the core Lorentz factor Gamma from the R-i anti-correlation, finding Gamma > 1.3., 18 pages, 12 figures, 6 tables

Treatment of 1-phospha-2,8,9-trioxaadamantane (III) with benzyl chloride, benzhydryl chloride, and 1-(chloromethyl) napthalene afforded a series of new bicyclic phosphonates which may be classified as derivatives of bicyclo[3.3.1]-nonane. Formation of 3-benzyl-7-chloro-2,4-dioxa-3-phosphalbicyclo[3.3.1]nonane, 3-oxide (IV-a) by a stereospecific, intramolecular Michaelis-Arbuzov rearrangement is indicated by stereochemical data via IR and NMR analysis. Although multiple separation in the NMR spectrum of IVa at 60 Mc was insufficiently resolved, the determination at 100 Mc gave excellent line separation. The double resonance technique was employed to verify peak assignments of the protons in IVa. Conformational homogeneity of the cyclohexane ring in IVa is postulated in view of the nine line grouping for the portion in an axial position at C1. Dipole moment measurements obtained on solutions of IVa in dioxane also support a boat-chair structure.

It is indicated that heteronuclear spin decoupling does aid the evaluation of 11boron spectra in that the information obtained is compatible with the information obtained from the 64.2 Mc/sec. spectra. It is noted that these spectral evaluations might suggest an unexpected consideration pertaining to spectral assignments. Both the ortho and meta isomers have one pair of equivalent boron nuclei more intimately neighbored to carbon than the four equivalent boron nuclei, and two pair of equivalent boron nuclei further removed from carbon than the four equivalent boron nuclei. This suggests that the spectra should have one doublet on one side of the resonance of the four equivalent boron nuclei and two doublets on the other side. In both cases, the doublet is at higher field than the resonance of the four equivalent boron nuclei, and the pair of doublets is at lower field. This seems to suggest that carbon could be imparting a diamagnetic shift to its neighboring boron nuclei. A paramagnetic shift would be expected if only relative electronegativities were considered.