Star cluster formation in the most extreme environments: Insights from the HiPEEC survey

التفاصيل البيبلوغرافية
العنوان: Star cluster formation in the most extreme environments: Insights from the HiPEEC survey
المؤلفون: Adamo, A., Hollyhead, K., Messa, M., Ryon, J. E., Bajaj, V., Runnholm, A., Aalto, S., Calzetti, D., Gallagher, J. S., Hayes, M. J., Kruijssen, J. M. D., König, S., Larsen, S. S., Melinder, J., Sabbi, E., Smith, L. J., Östlin, G.
سنة النشر: 2020
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Astrophysics of Galaxies
الوصف: We present the Hubble imaging Probe of Extreme Environments and Clusters (HiPEEC) survey. We fit HST NUV to NIR broadband and H$\alpha$ fluxes, to derive star cluster ages, masses, extinctions and determine the star formation rate (SFR) of 6 merging galaxies. These systems are excellent laboratories to trace cluster formation under extreme gas physical conditions, rare in the local universe, but typical for star-forming galaxies at cosmic noon. We detect clusters with ages of 1-500 Myr and masses that exceed $10^7$ M$_\odot$. The recent cluster formation history and their distribution within the host galaxies suggest that systems like NGC34, NGC1614, NGC4194 are close to their final coalescing phase, while NGC3256, NGC3690, NGC6052 are at an earlier/intermediate stage. A Bayesian analysis of the cluster mass function in the age interval 1-100 Myr provides strong evidence in 4 of the 6 galaxies that an exponentially truncated power law better describes the observed mass distributions. For two galaxies, the fits are inconclusive due to low number statistics. We determine power-law slopes $\beta \sim-1.5$ to $-2.0$, and truncation masses, M$_c$, between $10^6$ and a few times $10^7$ M$_\odot$, among the highest values reported in the literature. Advanced mergers have higher M$_c$ than early/intermediate merger stage galaxies, suggesting rapid changes in the dense gas conditions during the merger. We compare the total stellar mass in clusters to the SFR of the galaxy, finding that these systems are among the most efficient environments to form star clusters in the local universe.
Comment: Accepted for publication in MNRAS; data and catalogues will be released at this URL http://dx.doi.org/10.17909/t9-cn0b-ht83
نوع الوثيقة: Working Paper
DOI: 10.1093/mnras/staa2380
URL الوصول: http://arxiv.org/abs/2008.12794
رقم الأكسشن: edsarx.2008.12794
قاعدة البيانات: arXiv