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相关论文: On the collisional sensitivity of polarized Mg II …

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Interpretations of the very rich second solar spectrum of the MgH molecule face serious problems owing to the complete lack of any information about rates of collisions between the MgH and hydrogen atoms. This work seeks to begin the…

太阳与恒星天体物理 · 物理学 2021-07-27 Saleh Qutub , Yulia Kalugina , Moncef Derouich

Rigorous implementation of the effects of collisions in modeling the formation of the polarized solar lines is of utmost importance in order to realistically analyze the available, highly sensitive solar spectropolarimetric observations.…

太阳与恒星天体物理 · 物理学 2024-02-02 Moncef Derouich , Saleh Qutub

Simulations of the generation of the atomic polarization is necessary for interpreting the second solar spectrum. For this purpose, it is important to rigorously determine the effects of the isotropic collisions with neutral hydrogen on the…

太阳与恒星天体物理 · 物理学 2016-08-24 Moncef Derouich

This work aims to provide key elements to gain better understanding of the formation of the second solar spectrum of the Sr II $\lambda$4078 line. We show that in a certain range of hydrogen density, the effect of isotropic collisions…

太阳与恒星天体物理 · 物理学 2015-06-23 C. Deb , M. Derouich

This paper is a continuation of a series of studies investigating collisional depolarization of solar molecular lines like those of MgH, CN and C$_2$. It is focused on the case of the solar molecule C$_2$ which exhibits striking scattering…

太阳与恒星天体物理 · 物理学 2025-01-03 S. Qutub , Y. N. Kalugina , M. Derouich

Context: The scattering polarization of the infrared (IR) triplet of neutral oxygen (O\,\textsc{i}) near 777\,nm provides a powerful diagnostic of solar atmospheric conditions. However, interpreting such polarization requires a rigorous…

太阳与恒星天体物理 · 物理学 2026-01-14 Moncef Derouich , Saleh Qutub

The physical interpretation of scattering line polarization offers a novel diagnostic window for exploring the thermal and magnetic structure of the quiet regions of the solar atmosphere. Here we evaluate the impact of isotropic collisions…

天体物理学 · 物理学 2009-11-13 M. Derouich , J. Trujillo Bueno , R. Manso Sainz

Depolarizing collisions are elastic or quasielastic collisions that equalize the populations and destroy the coherence between the magnetic sublevels of atomic levels. In astrophysical plasmas, the main depolarizing collider is neutral…

A triplet of subordinate lines of Mg II exists in the region around the h&k lines. In solar spectra these lines are seen mostly in absorption, but in some cases can become emission lines. The aim of this work is to study the formation of…

太阳与恒星天体物理 · 物理学 2015-08-19 Tiago M. D. Pereira , Mats Carlsson , Bart De Pontieu , Viggo Hansteen

Analysis of solar magnetic fields using observations as well as theoretical interpretations of the scattering polarization is commonly designated as a high priority area of the solar research. The interpretation of the observed polarization…

太阳与恒星天体物理 · 物理学 2017-04-26 M. Derouich , H. Basurah , B. Badruddin

The next generation of solar observatories aim to understand the magnetism of the solar chromosphere. Therefore, it is crucial to understand the polarimetric signatures of chromospheric spectral lines. For this purpose, we here examine the…

Analysis of the Hanle effect in solar molecular lines allows us to obtain empirical information on hidden, mixed-polarity magnetic fields at subresolution scales in the (granular) upflowing regions of the `quiet' solar photosphere. Here we…

天体物理学 · 物理学 2009-11-13 A. Asensio Ramos , J. Trujillo Bueno

The Interface Region Imaging Spectrograph (IRIS) has routinely observed the flaring Mg II NUV spectrum, offering excellent diagnostic potential and a window into the location of energy deposition. A number of studies have forward modelled…

太阳与恒星天体物理 · 物理学 2019-10-02 G. S. Kerr , Joel C. Allred , Mats Carlsson

The polarization of the Mg II h and k lines holds significant diagnostic potential for measuring chromospheric magnetic fields, which are crucial for understanding the physical processes governing the energy transport and dissipation in the…

太阳与恒星天体物理 · 物理学 2026-01-01 Hao Li , Tanausú del Pino Alemán , Javier Trujillo Bueno

Solar irradiance and its variations in the ultraviolet (UV) control the photochemistry in Earth's atmosphere and influence Earth's climate. The variability of Mg II h and k core-to-wing ratio, also known as the Mg II index, is highly…

太阳与恒星天体物理 · 物理学 2025-01-07 K. Sowmya , M. Snow , A. I. Shapiro , N. A. Krivova , T. Chatzistergos , S. K. Solanki

This is a theoretical investigation on the formation of the linearly polarized line spectrum of ionized cerium in the sun. We calculate the scattering line polarization pattern emergent from a plane-parallel layer of Ce {\sc ii} atoms…

天体物理学 · 物理学 2009-11-11 R. Manso Sainz , E. Landi Degl'Innocenti , J. Trujillo Bueno

The Mg II h&k lines are amongst the best diagnostic tools of the upper solar chromosphere. This region of the atmosphere is of particular interest as it is the lowest region of the Sun's atmosphere where the magnetic field is dominant in…

太阳与恒星天体物理 · 物理学 2023-03-01 Viggo Hansteen , Juan Martinez Sykora , Mats Carlsson , Bart De Pontieu , Milan Gosic , Souvik Bose

Mg is often traced in late-type stars using lines of neutral magnesium, which is expected to be subject to departures from LTE. The astrophysical importance of Mg as well as its relative simplicity from an atomic physics point of view,…

太阳与恒星天体物理 · 物理学 2015-04-29 Y. Osorio , P. S. Barklem , K. Lind , A. K. Belyaev , A. Spielfiedel , M. Guitou , N. Feautrier

We carry out a theoretical study of the polarization of the solar Mg II h-k doublet (including its extended wings) and the subordinate UV triplet around 280 nm. These lines are of great diagnostic interest, as they encode information on the…

太阳与恒星天体物理 · 物理学 2020-04-21 T. del Pino Alemán , J. Trujillo Bueno , R. Casini , R. Manso Sainz

The bulk of the radiative output of a solar flare is emitted from the chromosphere, which produces enhancements in the optical and UV continuum, and in many lines, both optically thick and thin. We have, until very recently, lacked…

太阳与恒星天体物理 · 物理学 2015-10-07 Graham S. Kerr , Paulo J. A. Simões , Jiong Qiu , Lyndsay Fletcher
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