Nucleosynthesis in neutrino-driven, aspherical supernova explosion of a massive star

A massive star has been believed to end his life with the collapsed driven supernova explosion and the formation of the compact object such as a neutron star or a black hole. When the compact object is formed, a large amount of energy corresponding to the binding energy of the object must be released. It has been considered that most of the energy is emitted by neutrinos because of their adequate coupling with the matter. The observation of the neutrino burst from SN1987A by Kamiokande and IMB offered us the first chance to test these scenarios of the collapse driven supernova explosion directly. We began to analyze the data just after their publication and got many important results which are presented below. In our analysis the distance of SN1987A is assumed to be 50kpc.

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QCD phase transition drives supernova explosion of a very massive star

The European Physical Journal A ◽

10.1140/epja/s10050-021-00571-z ◽

2021 ◽

Vol 57 (9) ◽

Author(s):

Tobias Fischer

Keyword(s):

Phase Transition ◽

Massive Star ◽

Main Sequence ◽

Supernova Explosion ◽

Gluon Plasma ◽

First Order Phase Transition ◽

Solar Metallicity ◽

Low Metallicity ◽

First Order Phase

AbstractThe nature of core-collapse supernova (SN) explosions is yet incompletely understood. The present article revisits the scenario in which the release of latent heat due to a first-order phase transition, from normal nuclear matter to the quark–gluon plasma, liberates the necessary energy to explain the observed SN explosions. Here, the role of the metallicity of the stellar progenitor is investigated, comparing a solar metallicity and a low-metallicity case, both having a zero-age main sequence (ZAMS) mass of 75 M$$_\odot $$ ⊙ . It is found that low-metallicity models belong exclusively to the failed SN branch, featuring the formation of black holes without explosions. It excludes this class of massive star explosions as possible site for the nucleosynthesis of heavy elements at extremely low metallicity, usually associated with the early universe.

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An outburst from a massive star 40 days before a supernova explosion

Nature ◽

10.1038/nature11877 ◽

2013 ◽

Vol 494 (7435) ◽

pp. 65-67 ◽

Cited By ~ 141

Author(s):

E. O. Ofek ◽

M. Sullivan ◽

S. B. Cenko ◽

M. M. Kasliwal ◽

A. Gal-Yam ◽

...

Keyword(s):

Massive Star ◽

Supernova Explosion

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On the Origin of Hyperfast Neutron Stars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308015962 ◽

2007 ◽

Vol 3 (S246) ◽

pp. 365-366

Author(s):

V.V. Gvaramadze ◽

A. Gualandris ◽

S. Portegies Zwart

Keyword(s):

Neutron Star ◽

Neutron Stars ◽

Massive Star ◽

Galactic Disk ◽

Star Clusters ◽

Supernova Explosion ◽

Star Cluster ◽

Galactic Centre ◽

The Core ◽

Dense Cores

AbstractWe propose an explanation for the origin of hyperfast neutron stars (e.g. PSR B1508+55, PSR B2224+65, RX J0822–4300) based on the hypothesis that they could be the remnants of a symmetric supernova explosion of a high-velocity massive star (or its helium core) which attained its peculiar velocity (similar to that of the neutron star) in the course of a strong three- or four-body dynamical encounter in the core of a young massive star cluster. This hypothesis implies that the dense cores of star clusters (located either in the Galactic disk or near the Galactic centre) could also produce the so-called hypervelocity stars – ordinary stars moving with a speed of ~ 1 000 km s−1.

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On the origin of runaway binaries: the case of the HMXB 4U 2206+54/BD +53 2790

Communications of the Byurakan Astrophysical Observatory ◽

10.52526/25792776-2021.68.2-454 ◽

2021 ◽

pp. 454-463

Author(s):

V. Hambaryan ◽

K. A. Stoyanov ◽

M. Mugrauer ◽

R. Neuhäuser ◽

W. Stenglein ◽

...

Keyword(s):

Neutron Star ◽

Radial Velocity ◽

Massive Star ◽

Supernova Explosion ◽

Space Velocity ◽

High Mass ◽

Initial Mass ◽

X Ray ◽

Trace Back

We present most probable place and time of the origin of the runaway high-mass X-ray binary 4U 2206+54 based on its Gaia EDR3 astrometric parameters and our new systemic radial velocity. We studied the trace back motion of the system and propose that it originated in the subgroup of the Cepheus OB1 association (Age∼4-10 Myr) with its brightest star BD+53 2820 (B0V; L∼104.7L⊙). The kinematic age of 4U 2206+54 is about 2.8 ± 0.4 Myr, it is at a distance of 3.1-3.3 kpc and has a space velocity of 75-100 km/s with respect to this member star (BD+53 2820) of the Cep OB1 association. This runaway velocity indicates that the progenitor of the neutron star hosted by 4U 2206+54 lost about 4-9M⊙ during the supernova explosion and the latter one received a kick velocity of at least 200-350 km/s. The high-mass X-ray binary 4U 2206+54/BD+53 2790 was born as a member of a subgroup of the Cep OB1 association, the initially most massive star in the system terminated its evolution within ≲ 7 − 9 Myr, corresponding to an initial mass ≳ 32 M⊙.

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Outflowing Envelopes From Stars at Arbitrary Optical Depths a New Approach to the Problem

Highlights of Astronomy ◽

10.1017/s1539299600021316 ◽

1998 ◽

Vol 11 (1) ◽

pp. 381-381

Author(s):

A.V. Dorodnitsyn

Keyword(s):

Differential Equations ◽

Massive Star ◽

System Of Differential Equations ◽

Continuous Transition ◽

Satisfactory Description ◽

Sonic Point ◽

New Approach ◽

Star Evolution ◽

Matter Flux ◽

Massive Star Evolution

We have considered a stationary outflowing envelope accelerated by the radiative force in arbitrary optical depth case. Introduced approximations provide satisfactory description of the behavior of the matter flux with partially separated radiation at arbitrary optical depths. The obtained systemof differential equations provides a continuous transition of the solution between optically thin and optically thick regions. We analytically derivedapproximate representation of the solution at the vicinity of the sonic point. Using this representation we numerically integrate the system of equations from the critical point to the infinity. Matching the boundary conditions we obtain solutions describing the problem system of differential equations. The theoretical approach advanced in this work could be useful for self-consistent simulations of massive star evolution with mass loss.

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Gravitational waves from mountains in newly born millisecond magnetars

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab307 ◽

2021 ◽

Vol 502 (4) ◽

pp. 4680-4688

Author(s):

Ankan Sur ◽

Brynmor Haskell

Keyword(s):

Gravitational Wave ◽

Gravitational Waves ◽

Massive Star ◽

Gamma Ray ◽

Dipole Radiation ◽

X Ray ◽

Binary Neutron Star ◽

Spin Period ◽

Lower Maximum ◽

Wave Emission

ABSTRACT In this paper, we study the spin-evolution and gravitational-wave luminosity of a newly born millisecond magnetar, formed either after the collapse of a massive star or after the merger of two neutron stars. In both cases, we consider the effect of fallback accretion; and consider the evolution of the system due to the different torques acting on the star, namely the spin-up torque due to accretion and spin-down torques due to magnetic dipole radiation, neutrino emission, and gravitational-wave emission linked to the formation of a ‘mountain’ on the accretion poles. Initially, the spin period is mostly affected by the dipole radiation, but at later times, accretion spin the star up rapidly. We find that a magnetar formed after the collapse of a massive star can accrete up to 1 M⊙, and survive on the order of 50 s before collapsing to a black hole. The gravitational-wave strain, for an object located at 1 Mpc, is hc ∼ 10−23 at kHz frequencies, making this a potential target for next-generation ground-based detectors. A magnetar formed after a binary neutron star merger, on the other hand, accretes at the most 0.2 M⊙ and emits gravitational waves with a lower maximum strain of the order of hc ∼ 10−24, but also survives for much longer times, and may possibly be associated with the X-ray plateau observed in the light curve of a number of short gamma-ray burst.

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The effects of surface fossil magnetic fields on massive star evolution: III. The case of τ Sco

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab893 ◽

2021 ◽

Author(s):

Z Keszthelyi ◽

G Meynet ◽

F Martins ◽

A de Koter ◽

A David-Uraz

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Massive Star ◽

Slow Rotation ◽

Single Star ◽

Surface Magnetic Field ◽

Fundamental Parameters ◽

Chemical Enrichment ◽

Star Models ◽

Nitrogen Excess

Abstract τ Sco, a well-studied magnetic B-type star in the Uτer Sco association, has a number of surprising characteristics. It rotates very slowly and shows nitrogen excess. Its surface magnetic field is much more complex than a purely dipolar configuration which is unusual for a magnetic massive star. We employ the cmfgen radiative transfer code to determine the fundamental parameters and surface CNO and helium abundances. Then, we employ mesa and genec stellar evolution models accounting for the effects of surface magnetic fields. To reconcile τ Sco’s properties with single-star models, an increase is necessary in the efficiency of rotational mixing by a factor of 3 to 10 and in the efficiency of magnetic braking by a factor of 10. The spin down could be explained by assuming a magnetic field decay scenario. However, the simultaneous chemical enrichment challenges the single-star scenario. Previous works indeed suggested a stellar merger origin for τ Sco. However, the merger scenario also faces similar challenges as our magnetic single-star models to explain τ Sco’s simultaneous slow rotation and nitrogen excess. In conclusion, the single-star channel seems less likely and versatile to explain these discrepancies, while the merger scenario and other potential binary-evolution channels still require further assessment as to whether they may self-consistently explain the observables of τ Sco.

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High-sensitivity radio study of the non-thermal stellar bow shock EB27

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab662 ◽

2021 ◽

Author(s):

Paula Benaglia ◽

Santiago del Palacio ◽

Christopher Hales ◽

Marcelo E Colazo

Keyword(s):

Radio Emission ◽

Massive Star ◽

High Sensitivity ◽

Bow Shock ◽

Relativistic Electrons ◽

Polarimetric Observation ◽

Very Large Array ◽

Thermal Radio Emission ◽

The Magnetic Field ◽

Linear Polarisation

Abstract We present a deep radio-polarimetric observation of the stellar bow shock EB27 associated to the massive star BD+43○3654. This is the only stellar bow shock confirmed to have non-thermal radio emission. We used the Jansky Very Large Array in S band (2–4 GHz) to test whether this synchrotron emission is polarised. The unprecedented sensitivity achieved allowed us to map even the fainter regions of the bow shock, revealing that the more diffuse emission is steeper and the bow shock brighter than previously reported. No linear polarisation is detected in the bow shock above 0.5%, although we detected polarised emission from two southern sources, probably extragalactic in nature. We modeled the intensity and morphology of the radio emission to better constrain the magnetic field and injected power in relativistic electrons. Finally, we derived a set of more precise parameters for the system EB27–BD+43○3654 using Gaia Early Data Release 3, including the spatial velocity. The new trajectory, back in time, intersects the core of the Cyg OB2 association.

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