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Near-IR Integral Field Spectroscopy Study of the Star Formation and AGN of the LIRG NGC 5135
We present a study of the central 2.3 kpc of NGC 5135, a nearbyluminous infrared galaxy (LIRG) with an active galactic nucleus (AGN)and circumnuclear starburst. Our main results are based on intermediatespectral resolution (~3000-4000) near-infrared data taken with theSINFONI integral field spectrograph at the ESO VLT. The ionization ofthe different phases of the interstellar gas and the complex structuresof the star formation have been mapped. Individual regions of interesthave been identified and studied in detail. For the first time in thisgalaxy, we have detected the presence of a high excitation ionizationcone centered on the AGN by using the [Si VI]λ1.96 μm line. Sofar, this structure is the largest reported in the literature for thiscoronal line, extending (in projection) as far as ~600 pc from thegalaxy nucleus. In a complex spatial distribution, a variety ofmechanisms are driving the gas ionization, including supernova remnant(SNR) shocks, young stars and AGN photoionization. The excitation of themolecular gas, however, is mainly produced by X-rays and SNR shocks. UVmechanisms like fluorescence represent a marginal overall contributionto this process, contrary to the expectations we might have for a galaxywith a recent and strong star formation. Our supernova (SN) rateestimations from [Fe II]λ1.64 μm are in excellent agreementwith 6 cm radio emission predictions. Typical SN rates between 0.01and 0.04 yr-1 were found for individual ≈200 pc-scale regions, with an overall SN rate of 0.4-0.5yr-1. Even though NGC 5135 has suffered a recentstarburst (6-7 Myr ago), the data strongly suggest the presence of asecond, older stellar population dominated by red giant/supergiantstars. However, simple stellar population models cannot sharplydiscriminate between the different populations.
| Walraven photometry of nearby southern OB associations
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars inthe regions of five nearby southern OB associations: Scorpio Centaurus(Sco OB2), Orion OB1, Canis Major OB1, Monoceros OB1, and Scutum OB2.Derived V and (B - V) in the Johnson system are included.
| The local system of early type stars - Spatial extent and kinematics
Published uvby and H-beta photometric data and proper motions arecompiled and analyzed to characterize the structure and kinematics ofthe bright early-type O-A0 stars in the solar vicinity, with a focus onthe Gould belt. The selection and calibration techniques are explained,and the data are presented in extensive tables and graphs and discussedin detail. The Gould belt stars of age less than 20 Myr are shown togive belt inclination 19 deg to the Galactic plane and node-lineorientation in the direction of Galactic rotation, while the symmetricaldistribution about the Galactic plane and kinematic properties (purecircular differential rotation) of the belt stars over 60 Myr oldresemble those of fainter nonbelt stars of all ages. The unresolveddiscrepancy between the expansion observed in the youngest nearby starsand the predictions of simple models of expansion from a point isattributed to the inhomogeneous distribution of interstellar matter.
| Four-colour and H-beta photometry for early type stars in three southern galactic regions
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...41...85L&db_key=AST
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