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Related papers: Opacity of fluffy dust aggregates

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We present a synergic study of protoplanetary disks to investigate links between inner disk gas molecules and the large-scale migration of solid pebbles. The sample includes 63 disks where two types of measurements are available: i)…

Dust is known to drift and grow in protoplanetary discs, which results in dust segregation over the disc extent. Maps of the spectral index $\alpha$ are a common tool for studying the dust content in protoplanetary discs. The analysis of…

Instrumentation and Methods for Astrophysics · Physics 2019-04-17 Yaroslav Pavlyuchenkov , Vitaly Akimkin , Dmitri Wiebe , Eduard Vorobyov

We describe the use of partially overlapping galaxies to provide direct measurements of the effective absorption in galaxy disks, independent of assumptions about internal disk structure. The non-overlapping parts of the galaxies and…

Astrophysics · Physics 2007-05-23 Raymond E. White , William C. Keel , Christopher J. Conselice

The size and composition of dust grains are critical in setting the dynamical, physical and chemical evolution of the media in which they are present. Thanks to facilities such as ALMA and in the future the SKA, their thermal emission in…

Astrophysics of Galaxies · Physics 2019-11-06 N. Ysard , M. Koehler , I. Jimenez-Serra , A. P. Jones , L. Verstraete

We present 7-mm continuum observations of 14 low-mass pre-main-sequence stars in the Taurus-Auriga star-forming region obtained with the Very Large Array with ~1.5" resolution and ~0.3 mJy rms sensitivity. For 10 objects, the circumstellar…

Astrophysics · Physics 2009-11-11 J. Rodmann , Th. Henning , C. J. Chandler , L. G. Mundy , D. J. Wilner

(Abridged) We attempt to characterize the radial distribution of dust in disks around a sample of young stars from an observational point of view, and, when possible, in a model-independent way, by using parametric laws. We used the IRAM…

Astrophysics of Galaxies · Physics 2015-05-27 S. Guilloteau , A. Dutrey , V. Piétu , Y. Boehler

We study the behavior of large dust grains in turbulent molecular clouds (MCs). In primarily neutral regions, dust grains move as aerodynamic particles, not necessarily with the gas. We therefore directly simulate, for the first time, the…

Astrophysics of Galaxies · Physics 2016-11-09 Philip F. Hopkins , Hyunseok Lee

I summarize recent surveys of protoplanetary disks at millimeter wavelengths and show that the distribution of luminosity, equivalent to the mass in small dust grains, declines rapidly. This contrasts with statistics on the lifetime of…

Earth and Planetary Astrophysics · Physics 2015-06-05 Jonathan P. Williams

We examine the ``puffed-up inner disk'' model (Dullemond, Dominik & Natta 2001), proposed for explaining the near-IR excess radiation from Herbig Ae/Be stars. Detailed model computations show that the observed near-IR excess requires more…

Astrophysics · Physics 2009-11-11 Dejan Vinkovic , Zeljko Ivezic , Tomislav Jurkic , Moshe Elitzur

We provide simple polynomial fits to the X-ray photoelectric cross-sections (0.03 < E < 10keV) for mixtures of gas and dust found in protoplanetary disks. Using the solar elemental abundances of Asplund et al. (2009) we treat the gas and…

Solar and Stellar Astrophysics · Physics 2015-05-28 Thomas Bethell , Edwin Bergin

Our current understanding of the physical conditions in the inner regions of protoplanetary discs is becoming increasingly challenged by the more detailed observational and theoretical explorations. Calculation of dust temperature is one of…

Solar and Stellar Astrophysics · Physics 2011-12-05 Dejan Vinkovic

Debris disks give us the unique opportunity to probe the properties of small $\mu$m-sized particles, allowing us to peer into the constituents of their parent bodies, young analogs of comets and asteroids of our solar system. In the past,…

Earth and Planetary Astrophysics · Physics 2024-06-06 Johan Olofsson , Philippe Thébault , Amelia Bayo , Thomas Henning , Julien Milli

Aims: Grain growth has been suggested as one possible explanation for the diminished dust optical depths in the inner regions of protoplanetary "transition" disks. In this work, we directly test this hypothesis in the context of current…

Solar and Stellar Astrophysics · Physics 2012-06-28 T. Birnstiel , S. M. Andrews , B. Ercolano

This manuscript investigates the impact of key dust evolution parameters on dust retention and trapping in protoplanetary discs. Using models with and without pressure bumps, combined with radiative transfer simulations, images of the dust…

Earth and Planetary Astrophysics · Physics 2026-01-07 Paola Pinilla

We compare the ultra-violet, optical, and far-infrared emission for a sample of 135 spiral galaxies in order to address the widely debated problem concerning the opacity of spiral disks. We find that the re-radiation of the dust, estimated…

Astrophysics · Physics 2007-05-23 C. Xu , V. Buat

Cometary dust particles are remnants of the primordial accretion of refractory material that occurred during the initial stages of the Solar System formation. Understanding their physical structure can help constrain their accretion…

We present the results of a three dimensional, locally isothermal, non-self-gravitating SPH code which models protoplanetary disks with two fluids: gas and dust. We ran simulations of a 1 Msun star surrounded by a 0.01 Msun disk comprising…

The opacity of a spiral disk due to dust absorption influences every measurement we make of it in the UV and optical. Two separate techniques directly measure the total absorption by dust in the disk: calibrated distant galaxy counts and…

Astrophysics · Physics 2008-01-21 B. W. Holwerda , R. A. Gonzalez , W. C. Keel , D. Calzetti , R. J. Allen , P. C. van de Kruit

This review focuses on numerical approaches to deducing the light-scattering and thermal-emission properties of primitive dust particles in planetary systems from astronomical observations. The particles are agglomerates of small grains…

Earth and Planetary Astrophysics · Physics 2016-03-14 Hiroshi Kimura , Ludmilla Kolokolova , Aigen Li , Jérémy Lebreton

It is often argued that gravitational instability of realistic protoplanetary discs is only possible at distances larger than $\sim 50$ au from the central star, requiring high disc masses and accretion rates, and that therefore disc…

Earth and Planetary Astrophysics · Physics 2025-09-12 Hans Lee , Sergei Nayakshin , Richard A. Booth