SPICAand the Chemical Evolution of Galaxies: The Rise of Metals and Dust

Abstract

The physical processes driving the chemical evolution of galaxies in the last ∼ 11 Gyr cannot be understood without directly probing the dust-obscured phase of star-forming galaxies and active galactic nuclei. This phase, hidden to optical tracers, represents the bulk of star formation and black hole accretion activity in galaxies at 1 < z < 3. Spectroscopic observations with a cryogenic infrared (IR) observatory like SPICA will be sensitive enough to peer through the dustobscured regions of galaxies and access the rest-frame mid-to far-IR range in galaxies at high-z. This wavelength range contains a unique suite of spectral lines and dust features that serve as proxies for the abundances of heavy elements and the dust composition, providing tracers with a feeble response to both extinction and temperature. In this work, we investigate how SPICA observations could be exploited to understand key aspects in the chemical evolution of galaxies: the assembly of nearby galaxies based on the spatial distribution of heavy element abundances, the global content of metals in galaxies reaching the knee of the luminosity function up to z ∼ 3, and the dust composition of galaxies at high-z. Possible synergies with facilities available in the late 2020s are also discussed. Keywords: galaxies: evolution -galaxies: active -galaxies: starburst -infrared: galaxies -techniques: spectroscopic telescopes PrefaceThe following set of papers describe in detail the science goals of the future Space Infrared telescope for Cosmology and Astrophysics (SPICA). The SPICA satellite will employ a 2.5-m telescope, actively cooled to around 6 K, and a suite of mid-to far-IR spectrometers and photometric cameras, equipped with state of the art detectors. In particular the SPICA Far-Infrared Instrument (SAFARI) will be a grating spectrograph with low (R = 300) and medium (R 3 000-11 000) resolution observing modes instantaneously covering the 35-230 µm wavelength range. The SPICA Mid-Infrared Instrument (SMI) will have three operating modes: a large field of view (12 × 10 ) low-resolution 17-36 µm spectroscopic (R ∼ 50-120) and photometric camera at 34 µm, a medium resolution (R 2 000) grating spectrometer covering wavelengths of 17-36 µm, and a high-resolution echelle module (R 28 000) for the 12-18 µm domain. A large field of view (80 × 80 ), three channel (110, 220 and 350 µm), polarimetric camera will also be part of the instrument complement. These articles will focus on some of the major sci- *

PÉGASE.3: A code for modeling the UV-to-IR/submm spectral and chemical evolution of galaxies with dust

“…We also intend to implement in Pégase more-realistic models of dust grain composition and evolution, such as the one built with Themis (Jones et al 2017), and more-modern sets of stellar evolutionary tracks, spectra and chemical yields. However, in view of analyzing forthcoming infrared data, for example those that the SPICA space observatory will provide (Fernández-Ontiveros et al 2017) if selected for launch, our main effort will concentrate on the modeling of star-forming regions, in particular the competition between gas and dust in H ii regions to absorb ionizing photons and the effects of grains on nebular emission.…”

SPICA—A Large Cryogenic Infrared Space Telescope: Unveiling the Obscured Universe

“…These questions, their background science, and how SPICA would help resolve them, are discussed in much more detail in a dedicated series of papers (Spinoglio et al 2017;Fernández-Ontiveros et al 2017;González-Alfonso et al 2017;Gruppioni et al 2017;Kaneda et al 2017;E. Egami et al, in preparation;van der Tak et al 2017;P.…”

Probing the Baryon Cycle of Galaxies with SPICA Mid- and Far-Infrared Observations

“…An example of the first approach exists for small areas on the sky (Arendt et al 2010), and SPICA's sensitivity would enable such studies across entire galaxies, as done in the SMC by Sandstrom et al (2010), although further modeling efforts are needed. The second approach is interesting as a direct probe of the dust composition, as outlined in Fernández-Ontiveros et al (2017). At present, we have Fe and Si abundances from Spitzer observations (Okada et al 2008), but a good reference is lacking.…”

“…This paper describes the progress that can be made with SPICA in our understanding of the interstellar media of nearby galaxies. Companion papers by Spinoglio et al (2017), González-Alfonso et al (2017), Fernández-Ontiveros et al (2017, Gruppioni et al (2017), and Kaneda et al (2017) discuss the ability of SPICA to disentangle starburst nuclei from AGN, to study galactic winds and outflows, to probe the chemical evolution of galaxies, to carry out deep wide-field surveys of galaxies, and to probe the dust evolution of galaxies. The science case for the POL instrument is described by André et al (in prep), including topics in extragalactic polarimetry.…”