Results 1 to 10 of about 293,009 (201)

Strontium-84 Enrichments in Presolar Grains Provide First Evidence of p-process Nucleosynthesis in Core-collapse Supernovae

The Astrophysical Journal Letters
This study reports detection of rare p -process isotopes within presolar grains. Presolar grains are relic dust grains from dying stars. These microscopic dust particles are found in primitive solar system materials.
Ishita Pal, Manavi Jadhav, Danielle Z. Shulaker, Michael R. Savina, Marco Pignatari, Lorenzo Roberti, Heather Bouillion, Maria Lugaro, Christopher J. Dory, Frank Gyngard, Noriko Kita, Sachiko Amari   +11 more
doaj   +1 more source

Protostellar Chimney Flues: Are Jets and Outflows Lifting Submillimeter Dust Grains from Disks into Envelopes?

The Astrophysical Journal
Low dust opacity spectral indices ( β < 1) measured in the inner envelopes of class 0/I young stellar objects (age ∼10 ^4–5 yr) have been interpreted as the presence of (sub-)millimeter dust grains in these environments.
L. Cacciapuoti, L. Testi, L. Podio, C. Codella, A. J. Maury, M. De Simone, P. Hennebelle, U. Lebreuilly, R. S. Klessen, S. Molinari   +9 more
doaj   +1 more source

The Nucleated Atomistic Grain Growth Simulator (NAGGS): application to the size-dependent structural and physical properties of nanosilicate dust

Astronomy & Astrophysics
Context. The essential physics of dust grains are typically rationalised using phenomenological approaches, often assuming highly simplified grain morphologies.
Mariñoso Guiu Joan, Maciá Escatllar Antoni, Bromley Stefan T.   +2 more
doaj   +1 more source

The Spheroidal Analog Method for Modeling Irregular Porous Aggregates

The Astrophysical Journal
It is shown that the optical properties of an irregular porous grain with effective radius a _eff  ≲ 3 λ (where λ is the wavelength) can be well approximated by a “spheroidal analog”: a spheroid with appropriate axial ratio and size, with a dielectric ...
B. T. Draine
doaj   +1 more source

Submillimeter-wavelength Polarimetry of IRC+10216

The Astrophysical Journal
We present SCUBA-2/POL-2 850 μ m polarimetric observations of the circumstellar envelope (CSE) of the carbon-rich asymptotic giant branch (AGB) star IRC+10216.
B-G. Andersson, Janik Karoly, Pierre Bastien, Archana Soam, Simon Coudé, Mehrnoosh Tahani, Michael S. Gordon, Sydney Fox-Middleton   +7 more
doaj   +1 more source

The JWST Proto-PAH Project: Detection of the Methyl Radical CH3 in the Highly Evolved C-rich Object SMP LMC 011

The Astrophysical Journal Letters
We report the first detection of the neutral methyl radical CH _3 in a highly evolved C-rich object, SMP LMC 011, using the Mid-Infrared Instrument (MIRI) Medium-Resolution Spectrometer (MRS) on JWST.
Jialu Li, D. A. García-Hernández, A. Manchado, Debayan Das, J. Cami, Els Peeters, G. C. Sloan, B. Aringer, J. Bernard-Salas, C. Bhatt, Nicholas Clark, Harriet L. Dinerstein, M. A. Gómez-Muñoz, Kathleen E. Kraemer, M. Matsuura, R. Sahai, N. C. Sterling, Kevin Volk, G. M. Wahlgren, A. A. Zijlstra   +19 more
doaj   +1 more source

The Disks In Scorpius–Centaurus Survey (DISCS). I. Four Newly Resolved Debris Disks in Polarized Intensity Light

The Astronomical Journal
The presence of infrared excesses around stars directly correlates with spatially resolved imaging detections of circumstellar disks at both millimeter and optical/near-infrared wavelengths.
Justin Hom, Thomas M. Esposito, Katie A. Crotts, Gaspard Duchêne, Jennifer Patience, Johan Mazoyer, Robert J. De Rosa, Christine H. Chen, Paul Kalas, Bruce Macintosh, Brenda C. Matthews   +10 more
doaj   +1 more source

Detailed Radial Scale Height Profile of Dust Grains as Probed by Dust Self-scattering in HL Tau

The Astrophysical Journal Letters
The vertical settling of dust grains in a circumstellar disk, characterized by their scale height, is a pivotal process in the formation of planets. This study offers in-depth analysis and modeling of the radial scale height profile of dust grains in the
Haifeng Yang, Ian W. Stephens, Zhe-Yu Daniel Lin, Manuel Fernández-López, Zhi-Yun Li, Leslie W. Looney, Rachel Harrison   +6 more
doaj   +1 more source

Polycyclic aromatic hydrocarbon spectral diversity in NGC 7027 and the evolution of aromatic carriers

Astronomy & Astrophysics
Context. Polycyclic aromatic hydrocarbons (PAHs) constitute a significant fraction of the Universe’s carbon budget, playing a key role in the cosmic carbon cycle and dominating the mid-infrared spectra of astrophysical environments in which they reside ...
Smith-Perez Charlotte, Hembruff Aidan, Peeters Els, Tielens Alexander G. G. M., Ricca Alessandra   +4 more
doaj   +1 more source

Simulations of Multiple Dust Ring Formation in a Subsolar-metallicity Protoplanetary Disk

The Astrophysical Journal
Super-Earths exist around subsolar-metallicity host stars with a frequency comparable to that around solar-metallicity stars, suggesting efficient assembly of dust grains even in metal-deficient environments.
Ryoki Matsukoba, Eduard I. Vorobyov, Takashi Hosokawa   +2 more
doaj   +1 more source