Results 41 to 50 of about 10,429 (199)

Alfvén QPOs in Magnetars [PDF]

Journal of Physics: Conference Series, 2009
We investigate torsional Alfv n oscillations of relativistic stars with a global dipole magnetic field, via two-dimensional numerical simulations. We find that a) there exist two families of quasi-periodic oscillations (QPOs) with harmonics at integer multiples of the fundamental frequency, b) the lower-frequency QPO is related to the region of closed
Sotani, Hajime, Kokkotas, Kostas, Stergioulas, Nikolaos   +2 more
openaire   +2 more sources

Magnetars

, 2005
P-stars are compact stars made of up and down quarks in beta-equilibrium with electrons in a chromomagnetic condensate. P-stars are able to account for compact stars like RXJ 1856.5-3754 and RXJ 0720.4-3125, stars with radius comparable with canonical neutron stars, as well as super massive compact objects like SgrA*.
openaire   +4 more sources

On the initial spin periods of magnetars born in weak supernova explosions and their gravitational wave radiation

European Physical Journal C: Particles and Fields
The initial spin periods of newborn magnetars are strongly associated with the origin of their strong magnetic fields, both of which can affect the electromagnetic radiation and gravitational waves (GWs) emitted at their birth. Combining the upper limit $
Yu-Long Yan, Quan Cheng, Xiao-Ping Zheng, Xia-Xia Ouyang   +3 more
doaj   +1 more source

Heating and cooling of magnetars with accreted envelopes

, 2009
We study the thermal structure and evolution of magnetars as cooling neutron stars with a phenomenological heat source in an internal layer. We focus on the effect of magnetized (B > 10^{14} G) non-accreted and accreted outermost envelopes composed of ...
A. D. Kaminker, A. Y. Potekhin, Aguilera, Aguilera, Aguilera, Akmal, Alpar, Beloborodov, Bildsten, Chang, Chatterjee, Chevalier, Chevalier, Chugunov, Colpi, D. G. Yakovlev, Durant, Ertan, G. Chabrier, Geppert, Geppert, Ginzburg, Gnedin, Gudmundsson, Gusakov, Haensel, Ho, Kaminker, Kaminker, Kaminker, Kulkarni, Lattimer, Lyutikov, Mereghetti, Mereghetti, Morii, Morley, Muno, Nelson, Pavlov, Pons, Pons, Potekhin, Potekhin, Potekhin, Potekhin, Pérez-Azorín, Rea, Rea, Rho, Romanova, Shibanov, Slane, Tam, Thompson, Thompson, Tiengo, van Kerkwijk, Van Riper, Vancura, Vasisht, Ventura, Walter, Wang, Woods, Woods, Woods, Yakovlev, Yakovlev, Yakovlev   +69 more
core   +1 more source

Which Stars Form Black Holes and Neutron Stars? [PDF]

, 2006
I describe the current state of our knowledge of the mapping between the initial masses of stars and the compact objects -- particularly neutron stars and black holes -- that they produce.
Muno, Michael P.
core   +3 more sources

XMM‐Newton Observations of the Peculiar Be X‐Ray Binary A0538‐66

Astronomische Nachrichten, Volume 346, Issue 1, January 2025.
ABSTRACT A0538‐66 is a neutron star/Be x‐ray binary located in the Large Magellanic Cloud and, since its discovery in the 70s, it showed a peculiar behavior that makes it a unique object in the high‐mass x‐ray binaries scene: the extremely eccentric orbit (e=0.72$$ e=0.72 $$), the short spin period of the neutron star (P=69$$ P=69 $$ ms), the episodes ...
Michela Rigoselli, Caterina Tresoldi, Lorenzo Ducci, Sandro Mereghetti   +3 more
wiley   +1 more source

Zeeman Splitting of Torsional Oscillation Frequencies of Magnetars

Universe, 2023
Magnetars form a special class of neutron stars possessing superstrong magnetic fields and demonstrating power flares triggered by these fields. Observations of such flares reveal the presence of quasi-periodic oscillations (QPOs) at certain frequencies;
Dmitry Yakovlev
doaj   +1 more source

Wind braking of magnetars: To understand magnetars' multiwave radiation properties [PDF]

Astronomische Nachrichten, 2014
AbstractMagnetars are proposed to be peculiar neutron stars powered by their super‐strong magnetic field. Observationally, anomalous X‐ray pulsars and soft gamma‐ray repeaters are believed to be magnetar candidates. While more and more multiwave observations of magnetars are available, we see unfortunately an accumulation of failed predictions of the ...
Tong, H., Xu, R. X.
openaire   +2 more sources

The Role of XMM–Newton in the Investigation of Persistent BeXRBs

Astronomische Nachrichten, Volume 346, Issue 1, January 2025.
ABSTRACT The persistent BeXRBs are a class of high‐mass X‐ray binaries (HMXRBs), which are characterized by persistent low X‐ray luminosities (LX~1034$$ {L}_{\mathrm{X}}\sim {10}^{34} $$ erg s −1$$ {}^{-1} $$) and wide (Porb>$$ {P}_{\mathrm{orb}}> $$ 30 days), almost circular orbits. In these sources the NS is slowly rotating (with Pspin$$ {P}_{\mathrm{
Nicola La Palombara, Lara Sidoli, Sandro Mereghetti, Gian Luca Israel, Paolo Esposito   +4 more
wiley   +1 more source

Estimation of the detected background by the future gamma ray transient mission CAMELOT

Astronomische Nachrichten, Volume 340, Issue 7, Page 666-673, August 2019., 2019
Abstract This study presents a background estimation for the CubeSats Applied for MEasuring and LOcalising Transients (CAMELOT), which is a proposed fleet of nanosatellites for the all‐sky monitoring and timing‐based localization of gamma ray transients with precise localization capability at low Earth orbits.
Jakub Řípa, Gábor Galgóczi, Norbert Werner, András Pál, Masanori Ohno, László Mészáros, Tsunefumi Mizuno, Norbert Tarcai, Kento Torigoe, Nagomi Uchida, Yasushi Fukazawa, Hiromitsu Takahashi, Kazuhiro Nakazawa, Naoyoshi Hirade, Kengo Hirose, Syohei Hisadomi, Teruaki Enoto, Hirokazu Odaka, Yuto Ichinohe, Zsolt Frei, László Kiss   +20 more
wiley   +1 more source