Connecting the Interstellar Gas and Dust Properties in Distant Galaxies Using Quasar Absorption Systems

AbstractGas and dust grains are fundamental components of the interstellar medium and significantly impact many of the physical processes driving galaxy evolution, such as star-formation, and the heating, cooling, and ionization of the interstellar material. Quasar absorption systems (QASs), which trace intervening galaxies along the sightlines to luminous quasars, provide a valuable tool to directly study the properties of the interstellar gas and dust in distant, normal galaxies. We have established the presence of silicate dust grains in at least some gas-rich QASs, and find that they exist at higher optical depths than expected for diffuse gas in the Milky Way. Differences in the absorption feature shapes additionally suggest variations in the silicate dust grain properties, such as in the level of grain crystallinity, from system-to-system. We present results from a study of the gas and dust properties of QASs with adequate archival IR data to probe the silicate dust grain properties. We discuss our measurements of the strengths of the 10 and 18 μm silicate dust absorption features in the QASs, and constraints on the grain properties (e.g., composition, shape, crystallinity) based on fitted silicate profile templates. We investigate correlations between silicate dust abundance, reddening, and gas metallicity, which will yield valuable insights into the history of star formation and chemical enrichment in galaxies.

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Mentari: A pipeline to model the galaxy SED using semi analytic models

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319002813 ◽

2019 ◽

Vol 15 (S341) ◽

pp. 119-123

Author(s):

Dian Triani ◽

Darren Croton ◽

Manodeep Sinha

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Spectral Energy Distribution ◽

Cosmic Time ◽

Spectral Energy ◽

Chemical Enrichment ◽

The Galaxy ◽

History Of ◽

Gas Accretion ◽

Analytic Models

AbstractWe build a theoretical picture of how the light from galaxies evolves across cosmic time. In particular, we predict the evolution of the galaxy spectral energy distribution (SED) by carefully integrating the star formation and metal enrichment histories of semi-analytic model (SAM) galaxies and combining these with stellar population synthesis models which we call mentari. Our SAM combines prescriptions to model the interplay between gas accretion, star formation, feedback process, and chemical enrichment in galaxy evolution. From this, the SED of any simulated galaxy at any point in its history can be constructed and compared with telescope data to reverse engineer the various physical processes that may have led to a particular set of observations. The synthetic SEDs of millions of simulated galaxies from mentari can cover wavelengths from the far UV to infrared, and thus can tell a near complete story of the history of galaxy evolution.

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The Intricate Role of Cold Gas and Dust in Galaxy Evolution at Early Cosmic Epochs

Proceedings of the International Astronomical Union ◽

10.1017/s1743921315010315 ◽

2015 ◽

Vol 11 (S319) ◽

pp. 105-108

Author(s):

Dominik A. Riechers ◽

Peter L. Capak ◽

Christopher L. Carilli

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Galaxy Formation ◽

Big Bang ◽

Star Formation History ◽

Very Large Array ◽

Normal Galaxies ◽

Galaxy Formation And Evolution ◽

History Of ◽

The Big Bang

AbstractCold molecular and atomic gas plays a central role in our understanding of early galaxy formation and evolution. It represents the component of the interstellar medium (ISM) that stars form out of, and its mass, distribution, excitation, and dynamics provide crucial insight into the physical processes that support the ongoing star formation and stellar mass buildup. We here present results that demonstrate the capability of the Atacama Large (sub-)Millimeter Array (ALMA) to detect the cold ISM and dust in “normal” galaxies at redshifts z=5–6. We also show detailed studies of the ISM in massive, dust-obscured starburst galaxies out to z>6 with ALMA, the Combined Array for Research in Millimeter-wave Astronomy (CARMA), the Plateau de Bure Interferometer (PdBI), and the Karl G. Jansky Very Large Array (VLA). These observations place some of the most direct constraints on the dust-obscured fraction of the star formation history of the universe at z>5 to date, showing that “typical” galaxies at these epochs have low dust content, but also that highly-enriched, dusty starbursts already exist within the first billion years after the Big Bang.

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Catalytic Role of Refractory Interstellar Grain Analogs on H2 Formation

Frontiers in Astronomy and Space Sciences ◽

10.3389/fspas.2021.655883 ◽

2021 ◽

Vol 8 ◽

Author(s):

Tushar Suhasaria ◽

Vito Mennella

Keyword(s):

Molecular Hydrogen ◽

Laboratory Experiments ◽

Dust Grains ◽

Interstellar Gas ◽

Complex Molecules ◽

Catalytic Role ◽

H2 Formation ◽

Dust Grain

Refractory dust grains have an important role to play in the chemistry of star and planet-forming regions. Their surfaces interact with interstellar gas and act as a catalyst for the formation of simple and complex molecules in space. Several mechanisms have been invoked to explain how molecular hydrogen is formed in reactions on dust grain surfaces in different regions of space. In this article, we give an overview of our understanding of the laboratory experiments, conducted over the last 20 years, that deal with H2 formation on interstellar grain analogs in space simulated conditions.

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The star formation history of galaxies in 3D: CALIFA perspective

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314009399 ◽

2014 ◽

Vol 10 (S309) ◽

pp. 99-104

Author(s):

R. M. González Delgado ◽

R. Cid Fernandes ◽

R. García-Benito ◽

E. Pérez ◽

A. L. de Amorim ◽

...

Keyword(s):

Star Formation ◽

Surface Density ◽

Spectral Synthesis ◽

Stellar Mass ◽

Star Formation History ◽

Chemical Enrichment ◽

Radial Profiles ◽

Formation History ◽

The Galaxy ◽

History Of

AbstractWe resolve spatially the star formation history of 300 nearby galaxies from the CALIFA integral field survey to investigate: a) the radial structure and gradients of the present stellar populations properties as a function of the Hubble type; and b) the role that plays the galaxy stellar mass and stellar mass surface density in governing the star formation history and metallicity enrichment of spheroids and the disks of galaxies. We apply the fossil record method based on spectral synthesis techniques to recover spatially and temporally resolved maps of stellar population properties of spheroids and spirals with galaxy mass from 109 to 7×1011 M⊙. The individual radial profiles of the stellar mass surface density (μ⋆), stellar extinction (AV), luminosity weighted ages (〈logage〉L), and mass weighted metallicity (〈log Z/Z⊙〉M) are stacked in seven bins of galaxy morphology (E, S0, Sa, Sb, Sbc, Sc and Sd). All these properties show negative gradients as a sight of the inside-out growth of massive galaxies. However, the gradients depend on the Hubble type in different ways. For the same galaxy mass, E and S0 galaxies show the largest inner gradients in μ⋆; and Andromeda-like galaxies (Sb with log M⋆ (M⊙) ∼ 11) show the largest inner age and metallicity gradients. In average, spiral galaxies have a stellar metallicity gradient ∼ −0.1 dex per half-light radius, in agreement with the value estimated for the ionized gas oxygen abundance gradient by CALIFA. A global (M⋆-driven) and local (μ⋆-driven) stellar metallicity relation are derived. We find that in disks, the stellar mass surface density regulates the stellar metallicity; in spheroids, the galaxy stellar mass dominates the physics of star formation and chemical enrichment.

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The star formation history of the Fornax dwarf spheroidal galaxy

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310003200 ◽

2009 ◽

Vol 5 (S262) ◽

pp. 353-354

Author(s):

Enrico V. Held ◽

Eline Tolstoy ◽

Luca Rizzi ◽

Mary Cesetti ◽

Andrew A. Cole ◽

...

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Stellar Population ◽

Main Sequence ◽

Dwarf Galaxy ◽

Star Formation History ◽

Stellar Content ◽

Formation History ◽

First Results ◽

History Of

AbstractWe present the first results of a comprehensive HST study of the star-formation history of Fornax dSph, based on WFPC2 imaging of 7 Fornax fields. Our observations reach the oldest main-sequence turnoffs, allowing us to address fundamental questions of dwarf galaxy evolution, such as the spatial variations in the stellar content, and whether the old stellar population is made up of stars formed in a very early burst or the result of a more continuous star formation.

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CALIFA survey: The spatially resolved star formation history of massive galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313005097 ◽

2012 ◽

Vol 8 (S295) ◽

pp. 300-303

Author(s):

Rosa González Delgado ◽

Enrique Pérez ◽

Roberto Cid Fernandes ◽

Rubén García-Benito ◽

André de Amorim ◽

...

Keyword(s):

Growth Rate ◽

Star Formation ◽

Galaxy Evolution ◽

Local Density ◽

Spectral Synthesis ◽

Mass Density ◽

Stellar Mass ◽

Star Formation History ◽

Formation History ◽

History Of

AbstractThe Calar Alto Legacy Integral Field Area (CALIFA) project is an ongoing 3D spectroscopic survey of 600 nearby galaxies of all kinds. This pioneer survey is providing valuable clues on how galaxies form and evolve. Processed through spectral synthesis techniques, CALIFA datacubes allow us to, for the first time, spatially resolve the star formation history of galaxies spread across the color-magnitude diagram. The richness of this approach is already evident from the results obtained for the first ~ 1/6 of the sample. Here we show how the different galactic spatial sub-components (“bulge” and “disk”) grow their stellar mass over time. We explore the results stacking galaxies in mass bins, finding that, except at the lowest masses, galaxies grow inside-out, and that the growth rate depends on a galaxy's mass. The growth rate of inner and outer regions differ maximally at intermediate masses. We also find a good correlation between the age radial gradient and the stellar mass density, suggesting that the local density is a main driver of galaxy evolution.

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Effects of Supernova Feedback on the Formation of Galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308027828 ◽

2008 ◽

Vol 4 (S254) ◽

pp. 369-374

Author(s):

Cecilia Scannapieco ◽

Patricia B. Tissera ◽

Simon D. M. White ◽

Volker Springel

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Chemical Properties ◽

Multiphase Model ◽

Energy Feedback ◽

Chemical Enrichment ◽

Feedback Model ◽

Type Ia ◽

Virial Mass ◽

Hydrodynamical Simulations

AbstractWe study the effects of Supernova (SN) feedback on the formation of galaxies using hydrodynamical simulations in a ΛCDM cosmology. We use an extended version of the code GADGET-2 which includes chemical enrichment and energy feedback by Type II and Type Ia SN, metal-dependent cooling and a multiphase model for the gas component. We focus on the effects of SN feedback on the star formation process, galaxy morphology, evolution of the specific angular momentum and chemical properties. We find that SN feedback plays a fundamental role in galaxy evolution, producing a self-regulated cycle for star formation, preventing the early consumption of gas and allowing disks to form at late times. The SN feedback model is able to reproduce the expected dependence on virial mass, with less massive systems being more strongly affected.

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Molecular Gas in Galaxies at all Redshifts

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311022447 ◽

2010 ◽

Vol 6 (S277) ◽

pp. 47-54

Author(s):

Françoise Combes

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Star Formation History ◽

Gas Content ◽

Continuum Emission ◽

Massive Galaxies ◽

Normal Galaxies ◽

Galaxy Type ◽

Formation History ◽

Formation Efficiency

AbstractI review some recent results about the molecular content of galaxies, obtained essentially from the CO lines, but also dense tracers, or the dust continuum emission. New results have been obtained on molecular cloud physics, and their efficiency to form stars, shedding light on the Kennicutt-Schmidt law as a function of surface density and galaxy type. Large progress has been made on galaxy at moderate and high redshifts, allowing to interprete the star formation history and star formation efficiency as a function of gas content, or galaxy evolution. In massive galaxies, the gas fraction was higher in the past, and galaxy disks were more unstable and more turbulent. ALMA observations will allow the study of more normal galaxies at high z with higher spatial resolution and sensitivity.

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Modelling the carbon AGB star R Sculptoris

Astronomy and Astrophysics ◽

10.1051/0004-6361/201732065 ◽

2018 ◽

Vol 614 ◽

pp. A17 ◽

Cited By ~ 2

Author(s):

M. Brunner ◽

M. Maercker ◽

M. Mecina ◽

T. Khouri ◽

F. Kerschbaum

Keyword(s):

Mass Loss ◽

Spectral Energy Distribution ◽

Expansion Velocity ◽

Agb Stars ◽

Dust Grains ◽

Dust Shell ◽

Shell Mass ◽

Dust Mass ◽

Dust Grain ◽

Grain Properties

Context. On the asymptotic giant branch (AGB), Sun-like stars lose a large portion of their mass in an intensive wind and enrich the surrounding interstellar medium with nuclear processed stellar material in the form of molecular gas and dust. For a number of carbon-rich AGB stars, thin detached shells of gas and dust have been observed. These shells are formed during brief periods of increased mass loss and expansion velocity during a thermal pulse, and open up the possibility to study the mass-loss history of thermally pulsing AGB stars. Aims. We study the properties of dust grains in the detached shell around the carbon AGB star R Scl and aim to quantify the influence of the dust grain properties on the shape of the spectral energy distribution (SED) and the derived dust shell mass. Methods. We modelled the SED of the circumstellar dust emission and compared the models to observations, including new observations of Herschel/PACS and SPIRE (infrared) and APEX/LABOCA (sub-millimeter). We derived present-day mass-loss rates and detached shell masses for a variation of dust grain properties (opacities, chemical composition, grain size, and grain geometry) to quantify the influence of changing dust properties to the derived shell mass. Results. The best-fitting mass-loss parameters are a present-day dust mass-loss rate of 2 × 10−10 M⊙ yr−1 and a detached shell dust mass of (2.9 ± 0.3) × 10−5 M⊙. Compared to similar studies, the uncertainty on the dust mass is reduced by a factor of 4. We find that the size of the grains dominates the shape of the SED, while the estimated dust shell mass is most strongly affected by the geometry of the dust grains. Additionally, we find a significant sub-millimeter excess that cannot be reproduced by any of the models, but is most likely not of thermal origin.

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