%0 Generic %1 kreckel2016characterizing %A Kreckel, K. %A Blanc, G. A. %A Schinnerer, E. %A Groves, B. %A Adamo, A. %A Hughes, A. %A Meidt, S. %D 2016 %K HII arm interarm region %T Characterizing spiral arm and interarm star formation %U http://arxiv.org/abs/1603.08009 %X Interarm star formation contributes significantly to a galaxy's star formation budget, and provides an opportunity to study stellar birthplaces unperturbed by spiral arm dynamics. Using optical integral field spectroscopy of the nearby galaxy NGC 628 with VLT/MUSE, we identify 391 HII regions at 35pc resolution over 12 kpc^2. Using tracers sensitive to the underlying gravitational potential, we associate HII regions with either arm (271) or interarm (120) environments. We find that most HII region physical properties (luminosity, size, metallicity, ionization parameter) are independent of environment. We calculate the fraction of Halpha luminosity due to the diffuse ionized gas (DIG) background contaminating each HII region, and find the DIG surface brightness to be higher within HII regions compared to the surroundings, and slightly higher within arm HII regions. Use of the temperature sensitive SII/Halpha line ratio map instead of the Halpha surface brightness to identify HII region boundaries does not change this result. Using the dust attenuation as a tracer of the gas, we find relatively short depletion times (6 x 10^8 yr) with no differences between the arm and interarm, however this is very sensitive to the DIG correction. Unlike molecular clouds, which can be dynamically affected by the galactic environment, we see fairly consistent HII region properties in both arm and interarm environments. This suggests either a difference in arm star formation and feedback, or a decoupling of dense star forming clumps from the more extended surrounding molecular gas.

@misc{kreckel2016characterizing, abstract = {Interarm star formation contributes significantly to a galaxy's star formation budget, and provides an opportunity to study stellar birthplaces unperturbed by spiral arm dynamics. Using optical integral field spectroscopy of the nearby galaxy NGC 628 with VLT/MUSE, we identify 391 HII regions at 35pc resolution over 12 kpc^2. Using tracers sensitive to the underlying gravitational potential, we associate HII regions with either arm (271) or interarm (120) environments. We find that most HII region physical properties (luminosity, size, metallicity, ionization parameter) are independent of environment. We calculate the fraction of Halpha luminosity due to the diffuse ionized gas (DIG) background contaminating each HII region, and find the DIG surface brightness to be higher within HII regions compared to the surroundings, and slightly higher within arm HII regions. Use of the temperature sensitive [SII]/Halpha line ratio map instead of the Halpha surface brightness to identify HII region boundaries does not change this result. Using the dust attenuation as a tracer of the gas, we find relatively short depletion times (6 x 10^8 yr) with no differences between the arm and interarm, however this is very sensitive to the DIG correction. Unlike molecular clouds, which can be dynamically affected by the galactic environment, we see fairly consistent HII region properties in both arm and interarm environments. This suggests either a difference in arm star formation and feedback, or a decoupling of dense star forming clumps from the more extended surrounding molecular gas.}, added-at = {2016-03-29T10:10:56.000+0200}, author = {Kreckel, K. and Blanc, G. A. and Schinnerer, E. and Groves, B. and Adamo, A. and Hughes, A. and Meidt, S.}, biburl = {https://www.bibsonomy.org/bibtex/2e799193370cb75c720fda45a3723de3c/miki}, description = {[1603.08009] Characterizing spiral arm and interarm star formation}, interhash = {fa172a0ae82dd30edff0cc9c25a506b1}, intrahash = {e799193370cb75c720fda45a3723de3c}, keywords = {HII arm interarm region}, note = {cite arxiv:1603.08009Comment: 8 pages, 4 figures, 1 table, submitted to ApJ Letters}, timestamp = {2016-03-29T10:10:56.000+0200}, title = {Characterizing spiral arm and interarm star formation}, url = {http://arxiv.org/abs/1603.08009}, year = 2016 }