We present optical and IR integrated colours and SBF magnitudes, computed from stellar population synthesis models that include emission from the dusty envelopes surrounding TP-AGB stars undergoing mass-loss. We explore the effects of varying the mass-loss rate by one order of magnitude around the fiducial value, modifying accordingly both the stellar parameters and the output spectra of the TP-AGB stars plus their dusty envelopes. The models are single burst, and range in age from a few Myr to 14 Gyr, and in metallicity between $Z$ = 0.0001 and $Z$ = 0.07; they combine new calculations for the evolution of stars in the TP-AGB phase, with star plus envelope SEDs produced with the radiative transfer code DUSTY. We compare these models to optical and near-IR data of single AGB stars and Magellanic star clusters. This comparison validates the current understanding of the role of mass-loss in determining stellar parameters and spectra in the TP-AGB. However, neither broad-band colours nor SBF measurements in the optical or the near-IR can discern global changes in the mass-loss rate of a stellar population. We predict that mid-IR SBF measurements can pick out such changes, and actually resolve whether a relation between metallicity and mass-loss exists.
LIGHTS. Limitations of Far-Infrared Tracers for Galactic Cirrus Mitigation in the Era of Ultra-Deep Imaging
University of Padova(帕多瓦大学);Institute of Space Sciences (ICE, CSIC)(空间科学研究所);Instituto de Astrofísica de Canarias(加那利天体物理研究所);Universidad de La Laguna(拉古纳大学);Steward Observatory and Department of Astronomy, University of Arizona(亚利桑那大学斯图尔德天文台及天文系);Universidad de Córdoba(科尔多瓦大学)
The [CII] 157.74 $μ$m transition is the dominant coolant of the neutral interstellar gas, and has great potential as a star formation rate (SFR) tracer. Using the Herschel KINGFISH sample of 46 nearby galaxies, we investigate the relation of [CII] surface brightness and luminosity with SFR. We conclude that [CII] can be used for measurements of SFR on both global and kiloparsec scales in normal star-forming galaxies in the absence of strong active galactic nuclei (AGN). The uncertainty of the $Σ_{\rm [CII]}-Σ_{\rm SFR}$ calibration is $\pm$0.21 dex. The main source of scatter in the correlatio…
Intracluster globular clusters as tracers of the mass assembly of the Hydra I galaxy cluster
European Southern Observatory(欧洲南方天文台);Universitätssternwarte der Ludwig-Maximilians Universität(路德维希-马克西米利安大学大学天文台);INAF – Astronomical Observatory of Capodimonte(意大利国家天体物理研究所卡波迪蒙特天文台);Max-Planck-Institut für Extraterrestrische Physik(马克斯·普朗克地外物理学研究所);INAF – Astronomical Observatory of Abruzzo(意大利国家天体物理研究所阿布鲁佐天文台);Gran Sasso Science Institute(格兰萨索科学研究所)
Characterizing the properties of the host galaxies of merging compact objects provides essential clues to interpret current and future gravitational-wave detections. Here, we investigate the stellar mass, star formation rate (SFR), metallicity and colours of the host galaxies of merging compact objects in the local Universe, by combining the results of MOBSE population-synthesis models together with galaxy catalogs from the EAGLE simulation. We predict that the stellar mass of the host galaxy is an excellent tracer of the merger rate per galaxy ${\rm n}_{\rm GW}$ of double neutron stars (DNSs)…