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Related papers: Magnetic Fields in Dark Cloud Cores: Arecibo OH Ze…

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M dwarfs are known to generate the strongest magnetic fields among main-sequence stars with convective envelopes, but the link between the magnetic fields and underlying dynamo mechanisms, rotation, and activity still lacks a consistent…

New magnetic Ap stars with split Zeeman components are presented. These stars were discovered from observations with the FEROS spectrograph at the ESO 2.2-m telescope. Fifteen new magnetic stars are analysed here. Several stars with very…

Solar and Stellar Astrophysics · Physics 2015-06-03 V. G. Elkin , D. W. Kurtz , C. Nitschelm

Magnetic fields in cool stars can be investigated by measuring Zeeman line broadening and polarization in atomic and molecular lines. Similar to the Sun, these fields are complex and height-dependent. Many molecular lines dominating M-dwarf…

Solar and Stellar Astrophysics · Physics 2019-09-11 N. Afram , S. V. Berdyugina

Magnetic fields and turbulence may play a crucial role in the evolution of molecular clouds and ultimately in the formation of dense cores and stars. Despite being studied in many molecular clouds, the exact role of magnetic fields and…

Astrophysics of Galaxies · Physics 2026-03-26 A. Koley , P. Sanhueza , A. M. Stutz , P. Saha , F. A. Olguin , A. Ginsburg , N. Sandoval-Garrido , N. Castro-Toledo

We have measured the Zeeman splitting of OH megamaser emission at 1667 MHz from five (ultra)luminous infrared galaxies ([U]LIRGs) using the 305 m Arecibo telescope and the 100 m Green Bank Telescope. Five of eight targeted galaxies show…

Astrophysics · Physics 2009-11-13 Timothy Robishaw , Eliot Quataert , Carl Heiles

The ratio of mass and magnetic flux determines the relative importance of magnetic and gravitational forces in the evolution of molecular clouds and their cores. Its measurement is thus central in discriminating between different theories…

Solar and Stellar Astrophysics · Physics 2015-06-22 K. Tassis , K. Willacy , H. W. Yorke , N. J. Turner

Cool stars like the Sun harbor convection zones capable of producing substantial surface magnetic fields leading to stellar magnetic activity. The influence of stellar parameters like rotation, radius, and age on cool-star magnetism, and…

Solar and Stellar Astrophysics · Physics 2015-06-04 Ansgar Reiners

The question whether magnetic fields play an important role in the processes of molecular cloud and star formation has been debated for decades. Recent observations have revealed a simple picture that may help illuminate these questions:…

Astrophysics of Galaxies · Physics 2015-06-19 Hua-bai Li , Alyssa Goodman , T. K. Sridharan , Martin Houde , Zhi-Yun Li , Giles Novak , Kwok Sun Tang

We use magnetohydrodynamical simulations of converging flows to investigate the process of molecular cloud formation and evolution out of the magnetised ISM. Here, we investigate whether the observed subcritical HI clouds can become…

Astrophysics of Galaxies · Physics 2015-06-02 Bastian Körtgen , Robi Banerjee

Understanding the initial conditions of star formation requires both observational studies and theoretical works taking into account the magnetic field, which plays an important role in star formation processes. Herein, we study the young…

Solar and Stellar Astrophysics · Physics 2023-01-18 Sakiko Fukaya , Hiroko Shinnaga , Ray S. Furuya , Kohji Tomisaka , Masahiro N. Machida , Naoto Harada

Until recently, many of the dozens of quantitative predictions of the ambipolar-diffusion theory of gravitational fragmentation (or core formation) of molecular clouds have been confirmed by observations and, just as importantly, no…

Astrophysics · Physics 2008-07-30 Telemachos Ch. Mouschovias , Konstantinos Tassis

Due to dust grain alignment with magnetic fields, dust polarization observations of far-infrared emission from cold molecular clouds are often used to trace magnetic fields, allowing a probe of the effects of magnetic fields on the star…

Observations of the properties of dense molecular clouds are critical in understanding the process of star-formation. One of the most important, but least understood, is the role of the magnetic fields. We discuss the possibility of using…

In this chapter we review recent advances in understanding the roles that magnetic fields play throughout the star formation process, gained through observations and simulations of molecular clouds, the dense, star-forming phase of the…

Astrophysics of Galaxies · Physics 2022-03-22 Kate Pattle , Laura Fissel , Mehrnoosh Tahani , Tie Liu , Evangelia Ntormousi

Despite their rarity, massive stars dominate the ecology of galaxies via their strong, radiatively-driven winds throughout their lives and as supernovae in their deaths. However, their evolution and subsequent impact on their environment…

It has been proposed that the magnetic field, pervasive in the ISM, plays an important role in the process of massive star formation. To better understand its impact at the pre and protostellar stages, high-angular resolution observations…

Astrophysics of Galaxies · Physics 2020-09-30 C. Arce-Tord , F. Louvet , P. C. Cortes , F. Motte , C. L. H. Hull , V. J. M. Le Gouellec , G. Garay , T. Nony , P. Didelon , L. Bronfman

We expand our study on the dispersion of polarization angles in molecular clouds. We show how the effect of signal integration through the thickness of the cloud as well as across the area subtended by the telescope beam inherent to dust…

Astrophysics of Galaxies · Physics 2014-11-20 Martin Houde , John E. Vaillancourt , Roger H. Hildebrand , Shadi Chitsazzadeh , Larry Kirby

Context: The role of magnetic fields during high-mass star formation is a matter of fierce debate, yet only a few direct probes of magnetic field strengths are available. Aims: The magnetic field is detected in a number of massive…

Astrophysics · Physics 2009-11-13 W. H. T. Vlemmings

Massive O-type stars play a dominant role in our Universe, but many of their properties remain poorly constrained. In the last decade magnetic fields have been detected in all Galactic members of the distinctive Of?p class, opening the door…

Solar and Stellar Astrophysics · Physics 2017-05-24 S. Bagnulo , Y. Naze , I. D. Howarth , N. Morrell , J. S. Vink , G. A. Wade , N. Walborn , M. Romaniello , R. Barba