Star Formation Rate Distribution in the Galaxy NGC 1232
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 Hα 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 (log L > 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 Hα 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.
- Publication:
-
The Astronomical Journal
- Pub Date:
- June 2018
- DOI:
- arXiv:
- arXiv:1805.09911
- Bibcode:
- 2018AJ....155..234A
- Keywords:
-
- galaxies: individual: NGC 1232;
- galaxies: star formation;
- H ii regions;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 13 pages + table (27 pages), 8 figures