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Related papers: Magnetic flaring in pre-main sequence stars

200 papers

Solar flares occur due to the sudden release of energy stored in active-region magnetic fields. To date, the pre-cursors to flaring are still not fully understood, although there is evidence that flaring is related to changes in the…

Solar and Stellar Astrophysics · Physics 2012-02-01 Sophie A. Murray , D. Shaun Bloomfield , Peter T. Gallagher

Magnetic fields are considered to be key components of massive stars, with a far-reaching impact on their evolution and ultimate fate. A magnetic mechanism was suggested for the collimated explosion of massive stars, relevant for…

Solar and Stellar Astrophysics · Physics 2024-10-28 Swetlana Hubrig , Markus Schöller , Silva P. Järvinen , Aleksandar Cikota , Michael Abdul-Masih , Ana Escorza , Ilya Ilyin

Strong, kilo-Gauss, magnetic fields are required to explain a range of observational properties in young, accreting pre-main sequence (PMS) systems. We review the techniques used to detect magnetic fields in PMS stars. Key results from a…

Solar and Stellar Astrophysics · Physics 2015-06-18 Gaitee A. J. Hussain , Evelyne Alecian

The magnetic field plays an important role in every stage of the star-formation process from the collapse of the initial protostellar core to the star's arrival on the main sequence. Consequently, the goal of this science case is to explore…

Magnetars are young, highly magnetized neutron stars that are associated with magnetar short bursts (MSBs), magnetar giant flares (MGFs), and at least some fast radio bursts (FRBs). In this work, we consider a magnetar and a main sequence…

High Energy Astrophysical Phenomena · Physics 2024-08-20 Yu-Jia Wei , Yuan-Pei Yang , Da-Ming Wei , Zi-Gao Dai

For several decades we have been cognizant of the presence of magnetic fields in early-type stars, but our understanding of their magnetic properties has recently (over the last decade) expanded due to the new generation of high-resolution…

Solar and Stellar Astrophysics · Physics 2015-06-16 Jason H. Grunhut , Coralie Neiner

Magnetars are neutron stars in which a strong magnetic field is the main energy source. About two dozens of magnetars, plus several candidates, are currently known in our Galaxy and in the Magellanic Clouds. They appear as highly variable…

High Energy Astrophysical Phenomena · Physics 2015-06-24 Sandro Mereghetti , Jose' Pons , Andrew Melatos

The surface magnetic fields of pre-main-sequence stars and zero-age main-sequence stars are notably strong, resulting in the generation of numerous spots and the emission of bright chromospheric lines. Rotational variations in magnetic…

Solar and Stellar Astrophysics · Physics 2025-04-08 Mai Yamashita , Yoichi Itoh , Shin Toriumi

We investigate the connections between the magnetic fields and the X-ray emission from massive stars. Our study shows that the X-ray properties of known strongly magnetic stars are diverse: while some comply to the predictions of the…

Solar and Stellar Astrophysics · Physics 2015-05-30 L. M. Oskinova , W. -R. Hamann , J. P. Cassinelli , J. C. Brown , H. Todt

We demonstrate that for weak flares the dependence on spottedness can be rather weak. The fact is that such flares can occur both in small and large active regions. At the same time, powerful large flares of classes M and X occur much more…

Solar and Stellar Astrophysics · Physics 2022-09-07 M. M. Katsova , V. N. Obridko , D. D. Sokoloff , I. M. Livshits

We report on the status of our spectropolarimetric observations of massive stars. During the last years, we have discovered magnetic fields in many objects of the upper main sequence, including Be stars, beta Cephei and Slowly Pulsating B…

Solar and Stellar Astrophysics · Physics 2015-05-30 M. Schoeller , S. Hubrig , I. Ilyin , N. V. Kharchenko , M. Briquet , N. Langer , L. M. Oskinova , the MAGORI collaboration

Sudden relaxation of the magnetic field in the core of a magnetar produces mechanical energy primarily in the form of shear waves which propagate to the surface and enter the magnetosphere as relativistic Alfv\'en waves. Due to a strong…

Solar and Stellar Astrophysics · Physics 2015-06-18 Bennett Link

The non-thermal emission in the magnetospheres of presupernova collapsing stars with initial dipole magnetic fields and a certain initial energy distribution of the charged particles in a magnetosphere is considered. The analysis of…

Astrophysics · Physics 2009-11-10 Volodymyr Kryvdyk

In this article, we review some key aspects of a multi-wavelength flare which have essentially contributed to form a standard flare model based on the magnetic reconnection. The emphasis is given on the recent observations taken by the…

Solar and Stellar Astrophysics · Physics 2012-11-14 Bhuwan Joshi , Astrid Veronig , P. K. Manoharan , B. V. Somov

Magnetar bursts can be emitted by Alfv\'en waves growing in the outer magnetosphere to nonlinear amplitudes, $\delta B/B\sim 1$, and triggering magnetic reconnection. Similar magnetic flares should occur quasi-periodically in a magnetized…

High Energy Astrophysical Phenomena · Physics 2021-11-17 Andrei M. Beloborodov

In this contribution I review some of the major work that have been undertaken in the last decade to study the magnetic fields in intermediate-mass pre-main sequence stars, with the goal of understanding the origin of the magnetic fields…

Solar and Stellar Astrophysics · Physics 2013-10-08 E. Alecian

Magnetically confined winds of early-type stars are expected to be sources of bright and hard X-rays. To clarify the systematics of the observed X-ray properties, we have analyzed a large series of Chandra and XMM observations,…

Solar and Stellar Astrophysics · Physics 2016-03-09 Yael Naze , Veronique Petit , Melanie Rinbrand , David Cohen , Stan Owocki , Asif ud-Doula , Gregg A Wade

Pulsing X-ray emission tracks the plasma echo traveling in an extremely long magnetic tube that flares in an Orion Pre-Main Sequence (PMS) star. On the Sun, flares last from minutes to a few hours and the longest-lasting typically involve…

Solar and Stellar Astrophysics · Physics 2018-04-11 Fabio Reale , Javier Lopez-Santiago , Ettore Flaccomio , Antonino Petralia , Salvatore Sciortino

Violent solar flares and coronal mass ejections (CMEs) are magnetic phenomena. However, how magnetic fields reconnecting in the flare differ from non-flaring magnetic fields remains unclear owing to the lack of studies of the flare magnetic…

Solar and Stellar Astrophysics · Physics 2022-02-23 Maria D. Kazachenko , Benjamin J. Lynch , Antonia Savcheva , Xudong Sun , Brian T. Welsch

Magnetic fields appear wherever plasma and currents can be found. As such, they thread through all scales in Nature. It is natural, therefore, to suppose that magnetic fields might have been formed within the high temperature environments…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-16 Dai G. Yamazaki , Toshitaka Kajino , Grant J. Mathew , Kiyotomo Ichiki