scholarly journals Continuous gravitational wave from magnetized white dwarfs and neutron stars: possible missions for LISA, DECIGO, BBO, ET detectors

2019 ◽  
Vol 490 (2) ◽  
pp. 2692-2705 ◽  
Author(s):  
Surajit Kalita ◽  
Banibrata Mukhopadhyay
Keyword(s):  
Magnetic Field ◽  
Neutron Stars ◽  
Gravitational Wave ◽  
White Dwarfs ◽  
Direct Detection ◽  
Angular Frequency ◽  
Compact Objects ◽  
Rotation Axes ◽  
Type Ia ◽  
Ia Supernovae

ABSTRACT Recent detection of gravitational wave from nine black hole merger events and one neutron star merger event by LIGO and VIRGO shed a new light in the field of astrophysics. On the other hand, in the past decade, a few super-Chandrasekhar white dwarf candidates have been inferred through the peak luminosity of the light curves of a few peculiar Type Ia supernovae, though there is no direct detection of these objects so far. Similarly, a number of neutron stars with mass $>\! 2\, \mathrm{M}_\odot$ have also been observed. Continuous gravitational wave can be one of the alternate ways to detect these compact objects directly. It was already argued that magnetic field is one of the prominent physics to form super-Chandrasekhar white dwarfs and massive neutron stars. If such compact objects are rotating with certain angular frequency, then they can efficiently emit gravitational radiation, provided their magnetic field and rotation axes are not aligned, and these gravitational waves can be detected by some of the upcoming detectors, e.g. LISA, BBO, DECIGO, Einstein Telescope, etc. This will certainly be a direct detection of rotating magnetized white dwarfs as well as massive neutron stars.

The stellar graveyard

2019 ◽  
pp. 177-206
Author(s):  
Nils Andersson
Keyword(s):  
Black Holes ◽  
General Relativity ◽  
Neutron Stars ◽  
Gravitational Wave ◽  
Stellar Evolution ◽  
White Dwarfs ◽  
Supermassive Black Holes ◽  
Compact Objects ◽  
Fermi Gases ◽  
The 1950S

This chapter introduces the different classes of compact objects—white dwarfs, neutron stars, and black holes—that are relevant for gravitational-wave astronomy. The ideas are placed in the context of developing an understanding of the likely endpoint(s) of stellar evolution. Key ideas like Fermi gases and the Chandrasekhar mass are discussed, as is the emergence of general relativity as a cornerstone of astrophysics in the 1950s. Issues associated with different formation channels for, in particular, black holes are considered. The chapter ends with a discussion of the supermassive black holes that are found at the centre of galaxies.

scholarly journals Are the Precursors of Type Ia Supernovae Double Degenerate Mergers?

2004 ◽  
Vol 194 ◽  
pp. 111-112
Author(s):  
Lilia Ferrario
Keyword(s):  
Neutron Stars ◽  
White Dwarf ◽  
White Dwarfs ◽  
Observational Evidence ◽  
Type Ia Supernovae ◽  
Type Ia ◽  
Ia Supernovae

AbstractI argue that the observational evidence for white dwarf-white dwarf mergers supports the view that they give rise to ultra-massive white dwarfs or neutron stars through accretion induced collapse. The implications for the progenitors of Type Ia SNe are discussed.

scholarly journals Continuous gravitational waves from magnetized white dwarfs

2019 ◽  
Vol 15 (S357) ◽  
pp. 79-83
Author(s):  
Surajit Kalita ◽  
Banibrata Mukhopadhyay
Keyword(s):  
Gravitational Wave ◽  
Gravitational Waves ◽  
White Dwarfs ◽  
Type Ia Supernovae ◽  
Type Ia ◽  
Ia Supernovae

AbstractRecent evidence of super-Chandrasekhar white dwarfs (WDs), from the observations of over-luminous type Ia supernovae (SNeIa), has been a great astrophysical discovery. However, no such massive WDs have so far been observed directly as their luminosities are generally quite low. Hence it immediately raises the question of whether there is any possibility of detecting them directly. The search for super-Chandrasekhar WDs is very important as SNeIa are used as standard candles in cosmology. In this article, we show that continuous gravitational wave can allow us to detect such super-Chandrasekhar WDs directly.

scholarly journals White Dwarf Pulsars and Very Massive Compact Ultra Magnetized White Dwarfs

2017 ◽  
Vol 45 ◽  
pp. 1760024 ◽  
Author(s):  
Edson Otoniel ◽  
R. V. Lobato ◽  
M. Malheiro ◽  
Bruno Franzon ◽  
Stefan Schramm ◽  
...  
Keyword(s):  
Magnetic Field ◽  
White Dwarf ◽  
White Dwarfs ◽  
Carbon Ions ◽  
Poloidal Magnetic Field ◽  
Relativistic Approach ◽  
Type Ia ◽  
General Relativistic ◽  
Ia Supernovae ◽  
The Magnetic Field

In this work, we discuss white dwarf pulsars found recently making also reference of the possibility of some SGRs/AXPs being part of this class of pulsars. We also study the properties of very massive compact ultra magnetized white dwarfs that could be the progenitors candidates of super luminous type Ia supernovae, and also a previous stage of these white dwarf pulsars before the magnetic field decay.The structure of this ultra magnetized white dwarfs is obtained by solving the Einstein-Maxwell equations with a poloidal magnetic field in a fully general relativistic approach. The stellar interior is composed of a regular crystal lattice made of carbon ions immersed in a degenerate relativistic electron gas. We find that magnetized white dwarfs violate the standard Chandrasekhar mass limit significantly. We obtain a maximum white dwarf mass of around [Formula: see text] with an equatorial radius [Formula: see text] Km, a central magnetic field of [Formula: see text] G and [Formula: see text] G at the stellar surface.

scholarly journals Gravitational Collapse versus Thermonuclear Explosion of Degenerate Stellar Cores

1994 ◽  
Vol 147 ◽  
pp. 186-213
Author(s):  
J. Isern ◽  
R. Canal
Keyword(s):  
Neutron Star ◽  
White Dwarfs ◽  
Light Curves ◽  
Type Ia Supernovae ◽  
Radioactive Elements ◽  
Border Line ◽  
Thermonuclear Explosion ◽  
Type Ia ◽  
Γ Rays ◽  
Ia Supernovae

AbstractIn this paper we review the behavior of growing stellar degenerate cores. It is shown that ONeMg white dwarfs and cold CO white dwarfs can collapse to form a neutron star. This collapse is completely silent since the total amount of radioactive elements that are expelled is very small and a burst of γ-rays is never produced. In the case of an explosion (always carbonoxygen cores), the outcome fits quite well the observed properties of Type Ia supernovae. Nevertheless, the light curves and the velocities measured at maximum are very homogeneous and the diversity introduced by igniting at different densities is not enough to account for the most extreme cases observed. It is also shown that a promising way out of this problem could be the He-induced detonation of white dwarfs with different masses. Finally, we outline that the location of the border line which separetes explosion from collapse strongly depends on the input physics adopted.

scholarly journals Three Hypervelocity White Dwarfs in Gaia DR2: Evidence for Dynamically Driven Double-degenerate Double-detonation Type Ia Supernovae

2018 ◽  
Vol 865 (1) ◽  
pp. 15 ◽  
Author(s):  
Ken J. Shen ◽  
Douglas Boubert ◽  
Boris T. Gänsicke ◽  
Saurabh W. Jha ◽  
Jennifer E. Andrews ◽  
...  
Keyword(s):  
White Dwarfs ◽  
Type Ia Supernovae ◽  
Type Ia ◽  
Ia Supernovae ◽  
Gaia Dr2

scholarly journals Multidimensional Parameter Study of Double Detonation Type Ia Supernovae Originating from Thin Helium Shell White Dwarfs

2021 ◽  
Vol 919 (2) ◽  
pp. 126
Author(s):  
Samuel J. Boos ◽  
Dean M. Townsley ◽  
Ken J. Shen ◽  
Spencer Caldwell ◽  
Broxton J. Miles
Keyword(s):  
White Dwarfs ◽  
Parameter Study ◽  
Type Ia Supernovae ◽  
Multidimensional Parameter ◽  
Type Ia ◽  
Ia Supernovae

scholarly journals Type Ia supernovae and remnant neutron stars

2001 ◽  
Vol 320 (3) ◽  
pp. L45-L48 ◽  
Author(s):  
A. R. King ◽  
J. E. Pringle ◽  
D. T. Wickramasinghe
Keyword(s):  
Neutron Stars ◽  
Type Ia Supernovae ◽  
Type Ia ◽  
Ia Supernovae

scholarly journals Convection and spin-up during common envelope evolution: the formation of short-period double white dwarfs

2020 ◽  
Vol 497 (2) ◽  
pp. 1895-1903 ◽  
Author(s):  
E C Wilson ◽  
J Nordhaus
Keyword(s):  
Stellar Evolution ◽  
White Dwarfs ◽  
Orbital Parameter ◽  
Type Ia Supernovae ◽  
Core Mass ◽  
Common Envelope ◽  
Short Period ◽  
Type Ia ◽  
Ia Supernovae ◽  
Progenitor Stars

ABSTRACT The formation channels and predicted populations of double white dwarfs (DWDs) are important because a subset will evolve to be gravitational-wave sources and/or progenitors of Type Ia supernovae. Given the observed population of short-period DWDs, we calculate the outcomes of common envelope (CE) evolution when convective effects are included. For each observed white dwarf (WD) in a DWD system, we identify all progenitor stars with an equivalent proto-WD core mass from a comprehensive suite of stellar evolution models. With the second observed WD as the companion, we calculate the conditions under which convection can accommodate the energy released as the orbit decays, including (if necessary) how much the envelope must spin-up during the CE phase. The predicted post-CE final separations closely track the observed DWD orbital parameter space, further strengthening the view that convection is a key ingredient in CE evolution.

Sign in / Sign up

Export Citation Format

Share Document