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Related papers: Metals, dust and the cosmic microwave background: …

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We study star cluster formation at low metallicities of $Z/Z_\odot=10^{-4}$--$10^{-1}$ using three-dimensional hydrodynamics simulations. Particular emphasis is put on how the stellar mass distribution is affected by the cosmic microwave…

Astrophysics of Galaxies · Physics 2022-06-22 Sunmyon Chon , Haruka Ono , Kazuyuki Omukai , Raffaella Schneider

It has been hypothesized that the cosmic microwave background (CMB) provides a temperature floor for collapsing protostars that can regulate the process of star formation and result in a top-heavy initial mass function at high metallicity…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Jeremy Bailin , Greg Stinson , Hugh Couchman , William E. Harris , James Wadsley , Sijing Shen

The thermal and chemical evolution of star-forming clouds is studied for different gas metallicities, Z, using the model of Omukai (2000), updated to include deuterium chemistry and the effects of cosmic microwave background (CMB)…

Astrophysics · Physics 2009-11-10 K. Omukai , T. Tsuribe , R. Schneider , A. Ferrara

Modern (sub-)millimeter interferometers enable the measurement of the cool gas and dust emission of high-redshift galaxies (z>5). However, at these redshifts the cosmic microwave background (CMB) temperature is higher, approaching, and even…

Shocks may have been prevalent in the early Universe, associated with virialization and supernova explosions, etc. Here, we study thermal evolution and fragmentation of shock-compressed clouds, by using a one-zone model with detailed…

Astrophysics of Galaxies · Physics 2018-08-01 Daisuke Nakauchi , Kazuyuki Omukai , Raffaella Schneider

The thermal and fragmentation properties of star-forming clouds have important consequences on the corresponding characteristic stellar mass. The initial composition of the gas within these clouds is a record of the nucleosynthetic products…

Astrophysics · Physics 2009-11-11 Raffaella Schneider , Kazuyuki Omukai , Akio Inoue , Andrea Ferrara

We present a novel scenario for the growth of dust grains in galaxies at high-redshift ($z\sim 6$). In our model, the mechanical feedback from massive star clusters evolving within high-density pre-enriched media allows to pile-up a large…

Astrophysics of Galaxies · Physics 2021-09-02 Sergio Martínez-González , Sergiy Silich , Guillermo Tenorio-Tagle

I examine a possible spectral distortion of the Cosmic Microwave Background (CMB) due to its absorption by galactic and intergalactic dust. I show that even subtle intergalactic opacity of $1 \times 10^{-7}\, \mathrm{mag}\, h\,…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-16 Vaclav Vavrycuk

We explore the minimal conditions which enable the formation of metal-enriched solar and sub-solar mass stars. We find that in the absence of dust grains, gas fragmentation occurs at densities nH ~ [10^4-10^5]cm^{-3} when the metallicity…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Raffaella Schneider , Kazuyuki Omukai , Simone Bianchi , Rosa Valiante

The notion that dust might have formed the cosmic microwave background (CMB) has been strongly refuted on the strength of four decades of observation and analysis, in favour of recombination at a redshift z ~ 1080. But tension with the data…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-10 Fulvio Melia

A cosmological model, in which the cosmic microwave background (CMB) is a thermal radiation of intergalactic dust instead of a relic radiation of the Big Bang, is revived and revisited. The model suggests that a virtually transparent local…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-30 Vaclav Vavrycuk

Analyses of the cosmic microwave background (CMB) radiation maps made by the Wilkinson Microwave Anisotropy Probe (WMAP) have revealed anomalies not predicted by the standard inflationary cosmology. In particular, the power of the…

Earth and Planetary Astrophysics · Physics 2014-11-20 V. Dikarev , O. Preuss , S. Solanki , H. Krueger , A. Krivov

The characteristic mass of stars at early times may have been higher than today owing to the cosmic microwave background (CMB). This study proposes that (1) the testable predictions of this "CMB-IMF" hypothesis are an increase in the…

Astrophysics · Physics 2009-11-13 Jason Tumlinson

Simulations of the formation of Population III (Pop III) stars suggest that they were much more massive than the Pop II and Pop I stars observed today. This is due to the collapse dynamics of metal-free gas, which is regulated by the…

Future observations of CMB anisotropies will be able to probe high multipole regions of the angular power spectrum, corresponding to a resolution of a few arcminutes. Dust emission from merging haloes is one of the foregrounds that will…

Astrophysics · Physics 2010-11-11 Mattia Righi , Carlos Hernandez-Monteagudo , Rashid Sunyaev

Dust is ubiquitous in the Universe and its influence on the observed Electromagnetic (EM) radiation needs to be correctly addressed. In recent years it became clear that scattering of EM radiation from interstellar dust grains could change…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-21 Ariel Guerreiro , José Tito Mendonça , Robert Bingham

We investigate the condition for the formation of low-mass second-generation stars in the early universe. It has been proposed that gas cooling by dust thermal emission can trigger fragmentation of a low-metallicity star-forming gas cloud.…

In a low-metallicity gas, rapid cooling by dust thermal emission is considered to induce cloud fragmentation and play a vital role in the formation of low-mass stars (<~ 1 M_sun) in metal-poor environments. We investigate how the growth of…

Astrophysics of Galaxies · Physics 2013-02-13 Gen Chiaki , Takaya Nozawa , Naoki Yoshida

In cosmology, the quest for primordial $B$-modes in cosmic microwave background (CMB) observations has highlighted the critical need for a refined model of the Galactic dust foreground. We investigate diffusion-based modeling of the dust…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-13 David Heurtel-Depeiges , Blakesley Burkhart , Ruben Ohana , Bruno Régaldo-Saint Blancard

The first stars in the universe, termed Population III, are thought to have been very massive compared to the stars that form in the present epoch. As feedback from the first generation of stars altered the contents of the interstellar…

Solar and Stellar Astrophysics · Physics 2014-03-24 Gregory R. Meece , Britton D. Smith , Brian W. O'Shea
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