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Related papers: Evidence of Enhanced Ionization in Protostellar En…

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Protostellar disks are a ubiquitous part of the star formation process and the future sites of planet formation. As part of the Early Planet Formation in Embedded Disks (eDisk) large program, we present high-angular resolution dust…

Up to 90% of the chemical reactions during star formation occurs on ice surfaces, probably including the formation of complex organics. Only the most abundant ice species are however observed directly by infrared spectroscopy. This study…

Solar and Stellar Astrophysics · Physics 2015-05-13 Karin I. Oberg , Sandrine Bottinelli , Ewine F. van Dishoeck

Early dust grain growth in protostellar envelopes infalling on young discs has been suggested in recent studies, supporting the hypothesis that dust particles start to agglomerate already during the Class 0/I phase of young stellar objects…

Complex organic molecules (COMs), the building blocks of life, have been extensively detected under various physical conditions, from quiescent clouds to star-forming regions. They therefore serve as excellent tracers for the local physical…

Recent observations show that the CO gas abundance, relative to H$_2$, in many 1-10 Myr old protoplanetary disks may be heavily depleted, by a factor of 10-100 compared to the canonical interstellar medium value of 10$^{-4}$. When and how…

Earth and Planetary Astrophysics · Physics 2020-03-11 Ke Zhang , Kamber R. Schwarz , Edwin A. Bergin

We study the evolution of ionization fronts around the first proto-galaxies by using high resolution numerical cosmological (Lambda+CDM model) simulations and Monte Carlo radiative transfer methods. We present the numerical scheme in detail…

Astrophysics · Physics 2009-10-31 B. Ciardi , A. Ferrara , S. Marri , G. Raimondo

I use cosmological simulations that incorporate a physically motivated approximation to three-dimensional radiative transfer that recovers correct asymptotic ionization front propagation speeds for some cosmologically relevant density…

Astrophysics · Physics 2009-10-31 Nickolay Y. Gnedin

The crust of a neutron star is known to melt at a temperature that increases with increasing matter density, up to about $10^{10}$ K. At such high temperatures and beyond, the crustal ions are put into collective motion and the associated…

High Energy Astrophysical Phenomena · Physics 2023-09-06 H. Dinh Thi , A. F. Fantina , F. Gulminelli

We present a comprehensive analysis on the evolution of envelopes surrounding protostellar systems in the Perseus molecular cloud using data from the MASSES survey. We focus our attention to the C$^{18}$O(2--1) spectral line, and we…

Astrophysics of Galaxies · Physics 2022-03-14 Daniel J. Heimsoth , Ian W. Stephens , Hector G. Arce , Tyler L. Bourke , Philip C. Myers , Michael M. Dunham

The collapse of the protostellar envelope results in the growth of the protostar and the development of a protoplanetary disk, playing a critical role during the early stages of star formation. Characterizing the gas infall in the envelope…

Solar and Stellar Astrophysics · Physics 2020-03-11 Y. -L. Yang , N. J. Evans , A. Smith , J. -E. Lee , J. J. Tobin , S. Terebey , H. Calcutt , J. K. Jorgensen , J. D. Green , T. L. Bourke

The accretion histories of embedded protostars are an integral part of descriptions of their physical and chemical evolution. In particular, are the accretion rates smoothly declining from the earlier toward later stages or in fact…

Solar and Stellar Astrophysics · Physics 2015-06-24 Jes K. Jorgensen , Ruud Visser , Jonathan P. Williams , Edwin A. Bergin

Planetary systems such as our own are formed after a long process where matter condenses from diffuse clouds to stars, planets, asteroids, comets and residual dust, undergoing dramatic changes in physical and chemical state in less than a…

Solar and Stellar Astrophysics · Physics 2022-12-21 C. Ceccarelli , C. Codella , N. Balucani , D. Bockelée-Morvan , E. Herbst , C. Vastel , P. Caselli , C. Favre , B. Lefloch , K. Öberg

We investigate the role of carbon monoxide ice in the chemical evolution of prestellar cores using astrochemical rate equation models. We constrain the ratios of the binding energies on CO ice and H$_{2}$O ice for a series of adsorbates…

Astrophysics of Galaxies · Physics 2024-08-14 Germán Molpeceres , Kenji Furuya , Yuri Aikawa

We present an observational and theoretical study of the primary ionizing agents (cosmic rays and X-rays) in the TW Hya protoplanetary disk. We use a set of resolved and unresolved observations of molecular ions and other molecular species,…

Solar and Stellar Astrophysics · Physics 2015-06-23 L. Ilsedore Cleeves , Edwin A. Bergin , Chunhua Qi , Fred C. Adams , Karin I. Oberg

Observations of H3+ in the Galactic diffuse interstellar medium (ISM) have led to various surprising results, including the conclusion that the cosmic-ray ionization rate (zeta_2) is about 1 order of magnitude larger than previously…

Astrophysics of Galaxies · Physics 2015-06-03 Nick Indriolo , Benjamin J. McCall

The carbon isotope ratio is a powerful tool for studying the evolution of stellar systems. Recent detections of CO isotopologues in disks and exoplanet atmospheres pointed towards significant fractionation in these systems. In order to…

We present 870 um polarimetric observations toward 61 protostars in the Orion molecular clouds, with ~400 au (1") resolution using the Atacama Large Millimeter/submillimeter Array. We successfully detect dust polarization and outflow…

Protostellar jets are an important agent of star formation feedback, tightly connected with the mass-accretion process. The history of jet formation and mass-ejection provides constraints on the mass accretion history and the nature of the…

The evolution of protostellar outflow is investigated with resistive magneto-hydrodynamic nested-grid simulations that cover a wide range of spatial scales (\sim 1AU - 1pc). We follow cloud evolution from the pre-stellar core stage until…

Solar and Stellar Astrophysics · Physics 2015-06-15 Masahiro N. Machida , Takashi Hosokawa

We present a systematic study for ionization state of inter-stellar medium in galaxies at z=0-3 with ~140,000 SDSS galaxies and 108 intermediate to high redshift galaxies from the literature, using an ionization-parameter sensitive line…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Kimihiko Nakajima , Masami Ouchi
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