Context. Broad emission lines originate in the surroundings of supermassive black holes in the centers of active galactic nuclei (AGN). These broad-line emitting regions are spatially unresolved even for the nearest AGN. The origin and geometry of broad-line region (BLR) gas and their connection with geometrically thin or thick accretion disks is of fundamental importance for the understanding of AGN activity. Aims. One method to investigate the extent, structure, and kinematics of the BLR is to study the continuum and line profile variability in AGN. We selected the radio-loud Seyfert 1 galaxy 3C 120 as a target for this study. Methods. We took spectra with a high signal-to-noise ratio of 3C 120 with the 9.2 m Hobby-Eberly Telescope between Sept. 2008 and March 2009. In parallel, we photometrically monitored the continuum flux at the Wise observatory. We analyzed the continuum and line profile variations in detail (1D and 2D reverberation mapping) and modeled the geometry of the line-emitting regions based on the line profiles. Results. We show that the BLR in 3C 120 is stratified with respect to the distance of the line-emitting regions from the center with respect to the line widths (FWHM) of the rms profiles and with respect to the variability amplitude of the emission lines. The emission line wings of Hα and Hβ respond much faster than their central region. This is explained by accretion disk models. In addition, these lines show a stronger response in the red wings. However, the velocity-delay maps of the helium lines show a stronger response in the blue wing. Furthermore, the He ii λ4686 line responds faster in the blue wing in contradiction to observations made one and a half years later when the galaxy was in a lower state. The faster response in the blue wing is an indication for central outflow motions when this galaxy was in a bright state during our observations. The vertical BLR structure in 3C 120 coincides with that of other AGN. We confirm the general trend: the emission lines of narrow line AGN originate at larger distances from the midplane than AGN with broader emission lines.
We found an error in the header of Table I. In the last column, the E FS =E Bdl ratio should not have a ( 10 ÿ6 ) factor. We apologize for our error; it does not affect any numbers or figures in the original text.PHYSICAL REVIEW SPECIAL TOPICS -ACCELERATORS AND BEAMS 9, 089901 (2006) 1098-4402=06=9(8)=089901 (1) 089901-1
The reaction pp → K + + (Λp) was measured at T p = 1.953 GeV and Θ = 0 • with a high missing mass resolution in order to study the Λp final state interaction. The large final state enhancement near the Λp threshold can be described using the standard Jost-function approach. The singlet and triplet scattering lengths and effective ranges are deduced by fitting simultaneously the Λp invariant mass spectrum and the total cross section data of the free Λp scattering.
Excitation functions AN (p lab , Θc.m.) of the analyzing power in elastic proton-proton scattering have been measured in an internal target experiment at the Cooler Synchrotron COSY with an unpolarized proton beam and a polarized atomic hydrogen target. Data were taken continuously during the acceleration and deceleration for proton kinetic energies T lab (momenta p lab ) between 0.45 and 2.5 GeV (1.0 and 3.3 GeV/c) and scattering angles 30 • ≤ Θc.m. ≤ 90 • . The results provide excitation functions and angular distributions of high precision and internal consistency. The data can be used as calibration standard between 0.45 and 2.5 GeV. They have significant impact on phase shift solutions, in particular on the spin triplet phase shifts between 1.0 and 1.8 GeV. PACS. 25.40.Cm Elastic proton scattering -13.75.Cs Nucleon-nucleon interactions -24.70.+s Polarization phenomena in reactions -21.30.-x Nuclear forces
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