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Related papers: White Dwarf Bounds on CHAMPs

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We present current direct and astrophysical limits on the cosmological abundance of black holes with extremal magnetic charge. Because they don't Hawking radiate, much lighter primordial black holes could exist today if they are extremal.…

High Energy Physics - Phenomenology · Physics 2022-06-06 Melissa D. Diamond , David E. Kaplan

Supernovae of type Ia (SNe Ia) are believed to be thermonuclear explosions of carbon-oxygen white dwarfs (CO WDs). However, the mass accretion process onto CO WDs is still not completely understood. In this paper, we study the accretion of…

Solar and Stellar Astrophysics · Physics 2015-11-18 Bo Wang , Yan Li , Xin Ma , Dongdong Liu , Xiao Cui , Zhanwen Han

Almost every known planet host will evolve into a white dwarf, and the surviving planetary material will continue to orbit this stellar remnant. Asteroids perturbed onto star-grazing orbits will become disrupted, forming an accretion disk…

White Dwarfs (WD) capture Dark Matter (DM) as they orbit within their host halos. These captured particles may subsequently annihilate, heating the stellar core and preventing the WD from cooling. The potential wells of WDs are considerably…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Travis J. Hurst , Andrew R. Zentner , Aravind Natarajan , Carles Badenes

The physical trigger powering supernovae following the core collapse of massive stars is believed to involve a neutron star (NS) or a black hole (BH), depending largely on progenitor mass. A potentially distinct signature is a long-duration…

High Energy Astrophysical Phenomena · Physics 2024-08-28 Maurice H. P. M. van Putten , Maryam A. Abchouyeh , Massimo Della Valle

Accretion of mass onto a white dwarf (WD) in a binary system can lead to stellar explosions. If a WD accretes from stellar wind of a distant evolved giant in a symbiotic binary, it can undergo occasional outbursts in which it brightens by…

Solar and Stellar Astrophysics · Physics 2023-06-07 Augustin Skopal

Hot subdwarfs (sdBs) are core helium-burning stars, which lost almost their entire hydrogen envelope in the red-giant phase. Since a high fraction of those stars are in close binary systems, common envelope ejection is an important…

Solar and Stellar Astrophysics · Physics 2015-02-02 S. Geier , T. Kupfer , U. Heber , B. N. Barlow , P. F. L. Maxted , C. Heuser , V. Schaffenroth , E. Ziegerer , R. H. Østensen , B. T. Gänsicke

Orbital decay mechanisms argue that double white dwarf mergers are inevitable, but extremely rare. Whilst some mergers result in explosions, the survivors re-ignite helium and burn brightly for tens of thousands or millions of years.…

Solar and Stellar Astrophysics · Physics 2020-12-22 Simon Jeffery , Xianfei Zhang

The flame born in the deep interior of a white dwarf that becomes a Type Ia supernova is subject to several instabilities. We briefly review these instabilities and the corresponding flame acceleration. We discuss the conditions necessary…

Astrophysics · Physics 2009-10-28 J. C. Niemeyer , S. E. Woosley

We investigate observational properties of accretion-induced collapse (AIC) of white dwarfs in radio frequencies. If AIC is triggered by accretion from a companion star, a dense circumstellar medium can be formed around the progenitor…

High Energy Astrophysical Phenomena · Physics 2016-11-01 Takashi J. Moriya

Although supernovae is a well-known endpoint of an accreting white dwarf, alternative theoretical possibilities has been discussing broadly, such as the accretion-induced collapse (AIC) event as the endpoint of oxygen-neon (ONe) white…

The runaway collapse phase of a small dark matter cluster inside a white dwarf star encompasses a reversible stage, where heat can be transferred back and forth between nuclear and dark matter. Induced nuclear burning phases are stable and…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-26 Heinrich Steigerwald , Valerio Marra , Stefano Profumo

Ca-rich transients (CRTs, 2005E-like supernovae) exhibit unusually strong Ca features during their nebular phase, and their distribution in their host galaxies indicates that they belong to a metal-poor old population. We carried out a…

Solar and Stellar Astrophysics · Physics 2014-12-17 Xiangcun Meng , Zhanwen Han

We introduce a novel mechanism -- Magnetically Arrested Transmutation (MAT) -- which could be a viable model to account for the observed over-representation of magnetic white dwarfs (WDs) near the Galactic centre (GC), and the presence of a…

High Energy Astrophysical Phenomena · Physics 2026-03-17 H. A. Adarsha , Chandrachur Chakraborty , Sudip Bhattacharyya

Over 1500 DBZ or DZ white dwarfs (WDs) have been observed so far, and polluted atmospheres with metal elements have been found among these WDs. The surface heavy element abundances of known DBZ or DZ WDs show an evolutionary sequence. By…

Solar and Stellar Astrophysics · Physics 2021-10-13 Chunhua Zhu , Helei Liu , Zhaojun Wang , Guoliang Lv

By considering adiabatic contraction of the dark matter (DM) during star formation, we estimate the amount of DM trapped in stars at their birth. If the DM consists partly of primordial black holes (PBHs), they will be trapped together with…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-08 Fabio Capela , Maxim Pshirkov , Peter Tinyakov

Double white dwarf (double-WD) binaries may merge within a Hubble time and produce high-mass WDs. Compared to other high-mass WDs, the double-WD merger products have higher velocity dispersion because they are older. With the power of Gaia…

Solar and Stellar Astrophysics · Physics 2020-03-20 Sihao Cheng , Jeffrey D. Cummings , Brice Ménard , Silvia Toonen

One of the challenges to increasing the mass of a white dwarf through accretion is the tendency for the accumulating hydrogen to ignite unstably and potentially trigger mass loss. It has been known for many years that there is a narrow…

Astrophysics · Physics 2011-02-11 Ken J. Shen , Lars Bildsten

White dwarfs (WDs) that accrete helium at rates $\sim 10^{-8} \, M_\odot \, \rm yr^{-1}$, such as those in close binaries with sdB stars, can accumulate large ($\gtrsim 0.1 \, M_\odot$) helium envelopes which are likely to detonate. We…

Solar and Stellar Astrophysics · Physics 2017-08-30 Evan B. Bauer , Josiah Schwab , Lars Bildsten

Thermonuclear (type Ia) supernovae are explosions in accreting white dwarfs, but the exact scenario leading to these explosions is still unclear. An important step to clarify this point is to understand the behaviour of accreting white…

Astrophysics · Physics 2009-04-14 M. Hernanz , J. Jose
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