English
Related papers

Related papers: Modeling Grain Alignment by Radiative Torques and …

200 papers

The aim of this work is to provide new insights on the dynamics associated to the resonances which arise as a consequence of the coupling of the effect due to the oblateness of the Earth and the Solar Radiation Pressure (SRP) effect for an…

Earth and Planetary Astrophysics · Physics 2022-12-14 Roberto Paoli

In a recent article the authors showed that the radiative Transfer equations with multiple frequencies and scattering can be formulated as a nonlinear integral system. In the present article, the formulation is extended to handle reflective…

Numerical Analysis · Mathematics 2023-06-12 Olivier Pironneau , Pierre-Henri Tournier

Aligned grains provide one of the easiest ways to study magnetic fields in diffuse gas and molecular clouds. How reliable our conclusions about the inferred magnetic field depends critically on our understanding of the physics of grain…

Astrophysics · Physics 2008-11-26 Lazarian A

A model of dynamic orientation using optimized radiofrequency (RF) irradiation produced perpendicular to the holding field is developed for the spin-1 system required for tensor-polarized fixed-target experiments. The derivation applies to…

Nuclear Theory · Physics 2017-07-25 Dustin Keller

We investigate the claim that the ratio {\beta} of radiation pressure force to gravitational force on a dust grain in our solar system can substantially exceed unity for some grain sizes, provided that grain porosity is high enough. For…

Earth and Planetary Astrophysics · Physics 2016-03-09 Kedron Silsbee , Bruce T. Draine

We present an improved method to measure the rotation curves for disks with non-axisymmetric brightness profiles initially published in Teague et al. (2018a). Application of this method to the well studied AS$~$209 system shows substantial…

Earth and Planetary Astrophysics · Physics 2018-12-05 Richard Teague , Jaehan Bae , Tilman Birnstiel , Edwin Bergin

The phenomenological torque balance model previously introduced to describe the electrically assisted light-induced gliding is generalized to study the reorientation dynamics of the nematic liquid crystal easy axis at photoaligned azo-dye…

An uncommon double-ray scenario of light resonant scattering by a periodic metasurface is proposed to provide strong non-specular reflection. The metasurface is constracted as an array of silicon nanodisks placed on thin silica-on-metal…

It is shown, that mechanical alignment can be efficient for suprathermally rotating grains, provided that they drift with supersonic velocities. Such a drift should be widely spread due to both Alfv\'{e}nic waves and ambipolar diffusion.…

Astrophysics · Physics 2015-06-24 A. Lazarian

We present extensive calculations on the efficiency of grain alignment by the Davis-Greenstein mechanism. We model the grains as oblate spheroids with arbitrary axis ratios. Our description of the grain dynamics includes (i) magnetic…

Astrophysics · Physics 2010-10-27 W. G. Roberge , A. Lazarian

In this paper, we conduct a detailed study on the effect of Radiative Torque Disruption (RATD) mechanism on the fragmentation of micrometer-sized dust grains into nanoparticles within the heliosphere. We start by estimating the disruption…

Earth and Planetary Astrophysics · Physics 2025-02-28 Chi-Hang Ng , Pin-Gao Gu , Thiem Hoang

We present and analyse new optical images of the dust envelope surrounding the high mass-loss carbon star IRC+10216. This envelope is seen due to external illumination by galactic light. Intensity profiles and colors of the nebula were…

Astrophysics · Physics 2009-11-07 N. Mauron , P. de Laverny , B. Lopez

We present a study of hydrogen, helium, and carbon millimeter-wave radio-recombination lines (RRLs) toward ten representative positions throughout the Orion Nebula complex, using the Yebes 40m telescope in the Q band (31.3 GHz to 50.6 GHz)…

Astrophysics of Galaxies · Physics 2024-07-31 C. H. M. Pabst , J. R. Goicoechea , S. Cuadrado , P. Salas , A. G. G. M. Tielens , N. Marcelino

Atmospheric refraction affects to various degrees exoplanet transit, lunar eclipse, as well as stellar occultation observations. Exoplanet retrieval algorithms often use analytical expressions for the column abundance along a ray traversing…

Earth and Planetary Astrophysics · Physics 2017-03-23 Yan Betremieux , Lisa Kaltenegger

Stellar activity induced by active structures (eg, spots, faculae) is known to strongly impact the radial velocity time series. It then limits the detection of small planetary RV signals (eg, an Earth-mass planet in the habitable zone of a…

Solar and Stellar Astrophysics · Physics 2015-09-23 Simon Borgniet , Nadège Meunier , Anne-Marie Lagrange

Observations continue to support the interpretation of the anomalous microwave foreground as electric dipole radiation from spinning dust grains as proposed by Draine and Lazarian (1998ab). In this paper we present a refinement of the…

Astrophysics of Galaxies · Physics 2015-05-18 Thiem Hoang , B. T. Draine , A. Lazarian

The characterization of nearby rocky exoplanets will become feasible with the next generation of telescopes, such as the Extremely Large Telescope (ELT) and the mission concept Habitable Worlds Observatory (HWO). Using an improved model…

Earth and Planetary Astrophysics · Physics 2025-08-06 Giulia Roccetti , Michael F. Sterzik , Julia V. Seidel , Claudia Emde , Mihail Manev , Stefano Bagnulo

We present a new detailed model of the He I collisional-recombination spectrum based on the most up-to-date atomic data. The model accounts for radiative transfer effects and the influence of a non-zero optical depth in He I lines arising…

Astrophysics of Galaxies · Physics 2026-01-21 Oleg Kurichin , Alexandre Ivanchik

Stars form inside molecular cloud filaments from the competition of gravitational forces with turbulence and magnetic fields. The exact orientation of these filaments with the magnetic fields depends on the strength of these fields, the…

General relativistic ray tracing simulations of the time-averaged spectrum and energy-dependent time delays in AGN are presented. We model the lamp-post geometry in which the accreting gas is illuminated by an X-ray source located on the…

High Energy Astrophysical Phenomena · Physics 2016-07-27 P. Chainakun , A. J. Young , E. Kara