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arXiv · 1805.09911

Star Formation Rate Distribution in the Galaxy NGC 1232

Alexandre Araújo de Souza·Lucimara P. Martins·Alberto Rodríguez-Ardila·Luciano Fraga
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Abstract

NGC 1232 is a face-on spiral galaxy and a great laboratory for the study of star-formation due to its proximity. We obtained high spatial resolution H{\alpha} images of this galaxy, with adaptive optics, using the SAM instrument at the SOAR telescope, and used these images to study its H ii regions. These observations allowed us to produce the most complete H ii region catalog for it to date, with a total of 976 sources. This doubles the number of H ii regions previously found for this object. We used these data to construct the H ii luminosity function, and obtained a power-law index lower than the typical values found for Sc galaxies. This shallower slope is related to the presence of a significant number of high-luminosity H ii regions (logL>39 dex). We also constructed the size distribution function, verifying that, as for most galaxies, NGC 1232 follows an exponential law. We also used the H{\alpha} luminosity to calculate the star formation rate. An extremely interesting fact about this galaxy is that X-ray diffuse observations suggest that NGC 1232 recently suffered a collision with a dwarf galaxy. We found an absence of star formation around the region where the X-ray emission is more intense, which we interpret as a star formation quenching due to the collision. Along with that, we found an excess of star-forming regions in the northeast part of the galaxy, where the X-ray emission is less intense.

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Alexandre Araújo de Souza, Lucimara P. Martins, Alberto Rodríguez-Ardila, Luciano Fraga. 2018-05-24. Star Formation Rate Distribution in the Galaxy NGC 1232. https://doi.org/10.3847/1538-3881%2Faab6b2

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