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Neutral atoms may be trapped via the interaction of their magnetic dipole moment with magnetic field gradients. One of the possible schemes is the cloverleaf trap. It is often desirable to have at hand a fast and precise technique for…

Soft Condensed Matter · Physics 2007-05-23 Ph. W. Courteille , S. R. Muniz , K. Magalhaes , R. Kaiser , L. G. Marcassa , V. S. Bagnato

Magnetic fields of cool stars can be directly investigated through the study of the Zeeman effect on photospheric spectral lines using several approaches. With spectroscopic measurement in unpolarised light, the total magnetic flux averaged…

The weak, turbulent magnetic fields that supposedly permeate most of the solar photosphere are difficult to observe, because the Zeeman effect is virtually blind to them. The Hanle effect, acting on the scattering polarization in suitable…

Solar and Stellar Astrophysics · Physics 2015-05-19 F. Snik , A. G. de Wijn , K. Ichimoto , C. E. Fischer , C. U. Keller , B. W. Lites

The nonlinear magneto-optical effect has significantly impacted modern society with prolific applications ranging from precision mapping of the Earth's magnetic field to bio-magnetic sensing. Pioneering works on collisional spin-exchange…

Optics · Physics 2016-09-05 Feng Zhou , Chengjie Zhu , E. W. Hagley , L. Deng

We show that atomic alignment presents a reliable way to study topology of astrophysical magnetic fields. The effect of atomic alignment arises from modulation of the relative population of the sublevels of atomic ground state pumped by…

Astrophysics · Physics 2008-11-26 Huirong Yan , A. Lazarian

2008 marks the 100th anniversary of the discovery of astrophysical magnetic fields, when George Ellery Hale recorded the Zeeman splitting of spectral lines in sunspots. With the introduction of Babcock's photoelectric magnetograph it soon…

Solar and Stellar Astrophysics · Physics 2015-05-13 J. O. Stenflo

Model atmospheres of A and B stars are computed taking into account magnetic line blanketing. These calculations are based on the new stellar model atmosphere code LLModels which implements direct treatment of the opacities due to the…

Astrophysics · Physics 2009-11-10 O. Kochukhov , S. Khan , D. Shulyak

With the recent advent of circular polarization capabilities at the Atacama Large Millimeter/submillimeter Array (ALMA), Zeeman effect measurements of spectral lines are now possible as a means to directly probe line-of-sight magnetic…

Solar and Stellar Astrophysics · Physics 2020-11-04 Renato Mazzei , L. Ilsedore Cleeves , Zhi-Yun Li

Observational studies of magnetic fields are crucial. We introduce a process "ground state alignment" as a new way to determine the magnetic field direction in diffuse medium. The alignment is due to anisotropic radiation impinging on the…

Astrophysics of Galaxies · Physics 2013-02-15 Huirong Yan , A. Lazarian

Magnetic fields play an important role in the evolution of interstellar medium and star formation. As the only direct probe of interstellar field strength, credible Zeeman measurements remain sparse due to the lack of suitable Zeeman…

Astrophysics of Galaxies · Physics 2021-12-24 Tao-Chung Ching , Di Li , Carl Heiles , Zhi-Yun Li , Lei Qian , Youling Yue , Jing Tang , Sihan Jiao

Magnetic fields are regarded as a crucial element for our understanding of stellar physics. They can be studied with a variety of methods which provide complementary - and sometimes contradictory - information about the structure, strength…

Solar and Stellar Astrophysics · Physics 2015-06-11 J. Morin , M. Jardine , A. Reiners , D. Shulyak , B. Beeck , G. Hallinan , L. Hebb , G. Hussain , S. V. Jeffers , O. Kochukhov , A. Vidotto , L. Walkowicz

Zeeman-Doppler imaging is a spectropolarimetric technique that is used to map the large-scale surface magnetic fields of stars. These maps in turn are used to study the structure of the stars' coronae and winds. This method, however, misses…

Solar and Stellar Astrophysics · Physics 2015-06-18 P. Lang , M. Jardine , J. Morin , J-F. Donati , S. Jeffers , A. A. Vidotto , R. Fares

When using a recently developed method of Doppler-Zeeman mapping (Vasilchenko et al., 1996) for analysis of a real star and real observational data, we are confronted with limitations due to the model simplifications and unavoidable errors…

Astrophysics · Physics 2007-05-23 V. L. Khokhlova , D. V. Vasilchenko , V. V. Stepanov , V. V. Tsymbal

Magnetic fields play a crucial role in planetary evolution and habitability. While the intrinsic magnetic fields of solar system planets are relatively well understood, the magnetic properties of exoplanets remain largely unconstrained,…

The influence of a magnetic field on the broadening of spectral lines and transition arrays in complex spectra is investigated. The anomalous absorption or emission Zeeman pattern is a superposition of many profiles with different relative…

Atomic Physics · Physics 2019-04-30 Jean-Christophe Pain , Franck Gilleron

The behavior of the observed polarization amplitudes with spatial resolution is a strong constraint on the nature and organization of solar magnetic fields below the resolution limit. We study the polarization of the very quiet Sun at…

Solar and Stellar Astrophysics · Physics 2015-05-18 M. J. Martinez Gonzalez , R. Manso Sainz , A. Asensio Ramos , A. Lopez Ariste

The quantum theory of polarized light allows one to model scattering in the solar atmosphere for inferring its properties. This powerful approach has revealed two key long-standing problems in solar physics: the puzzling dilemmas between…

Solar and Stellar Astrophysics · Physics 2016-11-01 E. S. Carlin , M. Bianda

For the observational modeling of horizontal abundance distributions and of magnetic geometries in chemically peculiar (CP) stars, Zeeman Doppler mapping (ZDM) has become the method of choice. Comparisons between abundance maps obtained for…

Solar and Stellar Astrophysics · Physics 2021-04-13 M. J. Stift , F. Leone

We present a novel technique that uses the autocorrelation of the spectrum of a star to measure the line broadening caused by the modulus of its average surface magnetic field. The advantage of the autocorrelation comes from the fact that…

Solar and Stellar Astrophysics · Physics 2015-10-21 Ermanno F. Borra , David Deschatelets

The physics of the solar chromosphere depends in a crucial way on its magnetic structure. However there are presently very few direct magnetic field diagnostics available for this region. Here we investigate the diagnostic potential of the…

Astrophysics · Physics 2009-11-13 M. Faurobert , M. Derouich , V. Bommier , J. Arnaud