English
Related papers

Related papers: Linear growth of spiral SASI modes in core-collaps…

200 papers

We have studied non-axisymmetric standing accretion shock instability, or SASI, by 3D hydrodynamical simulations. This is an extention of our previous study on axisymmetric SASI. We have prepared a spherically symmetric and steady accretion…

Astrophysics · Physics 2013-08-30 Wakana Iwakami , Kei Kotake , Naofumi Ohnishi , Shoichi Yamada , Keisuke Sawada

A stalled spherical accretion shock, such as that arising in core-collapse supernovae, is unstable to non-spherical perturbations. In three dimensions, this Standing Accretion Shock Instability (SASI) can develop spiral modes that spin-up…

Solar and Stellar Astrophysics · Physics 2015-05-18 Rodrigo Fernández

We studied the effects of rotation on standing accretion shock instability (SASI) by performing three-dimensional hydrodynamics simulations. Taking into account a realistic equation of state and neutrino heating/cooling, we prepared a…

Astrophysics · Physics 2009-07-22 Wakana Iwakami , Kei Kotake , Naofumi Ohnishi , Shoichi Yamada , Keisuke Sawada

Hydrodynamical instabilities, such as the standing accretion-shock instability (SASI), play an essential role in the dynamics of core-collapse supernovae, with observable imprints in the neutrino and gravitational wave signals. Yet, the…

High Energy Astrophysical Phenomena · Physics 2023-03-15 Laurie Walk , Thierry Foglizzo , Irene Tamborra

A perturbative analysis is used to investigate the effect of rotation on the instability of a steady accretion shock (SASI) in a simple toy-model, in view of better understanding supernova explosions in which the collapsing core contains…

Astrophysics · Physics 2009-11-13 Tatsuya Yamasaki , Thierry Foglizzo

We use time-dependent, axisymmetric, hydrodynamic simulations to study the linear stability of the stalled, spherical accretion shock that arises in the post-bounce phase of core-collapse supernovae. We show that this accretion shock is…

Astrophysics · Physics 2009-11-13 John M. Blondin , Anthony Mezzacappa

(abridged) We study the hydrodynamic evolution of a non-spherical core-collapse supernova in two spatial dimensions. We find that our model displays a strong tendency to expand toward the pole. We demonstrate that this expansion is a…

Solar and Stellar Astrophysics · Physics 2016-11-18 A. Gawryszczak , J. Guzman , T. Plewa , K. Kifonidis

The spin of a neutron star at birth may be impacted by the asymmetric character of the explosion of its massive progenitor. During the first second after bounce, the spiral mode of the Standing Accretion Shock Instability (SASI) is able to…

High Energy Astrophysical Phenomena · Physics 2015-11-12 Rémi Kazeroni , Jérôme Guilet , Thierry Foglizzo

The explosion mechanism of core-collapse supernovae has not been fully understood yet but multi-dimensional fluid instabilities such as standing accretion shock instability (SASI) and convection are now believed to be crucial for shock…

High Energy Astrophysical Phenomena · Physics 2017-02-08 Kazuya Takahashi , Wakana Iwakami , Yu Yamamoto , Shoichi Yamada

Here we present the results from two sets of simulations, in two and three spatial dimensions. In two dimensions, the simulations include multifrequency flux-limited diffusion neutrino transport in the "ray-by-ray-plus" approximation,…

Astrophysics · Physics 2009-11-13 A. Mezzacappa , S. W. Bruenn , J. M. Blondin , W. R. Hix , O. E. B. Messer

By 2D hydrodynamic simulations including a detailed equation of state and neutrino transport, we investigate the interplay between different non-radial hydrodynamic instabilities that play a role during the postbounce accretion phase of…

Astrophysics · Physics 2009-06-23 L. Scheck , H. -Th. Janka , T. Foglizzo , K. Kifonidis

The success of the neutrino mechanism of core-collapse supernovae relies on the supporting action of two hydrodynamic instabilities: neutrino-driven convection and the Standing Accretion Shock Instability (SASI). Depending on the structure…

Solar and Stellar Astrophysics · Physics 2015-06-17 Rodrigo Fernández , Bernhard Mueller , Thierry Foglizzo , Hans-Thomas Janka

The stationary accretion shock instability (SASI) plays a central role in modern simulations of the explosion phase of core-collapse supernovae (CCSNe). It may be key to realizing neutrino powered explosions, and possibly links birth…

Solar and Stellar Astrophysics · Physics 2015-06-04 E. Endeve , C. Y. Cardall , R. D. Budiardja , A. Mezzacappa , J. M. Blondin

In this study, we conduct three-dimensional hydrodynamic simulations systematically to investigate the flow patterns behind the accretion shock waves that are commonly formed in the post-bounce phase of core-collapse supernovae. Adding…

High Energy Astrophysical Phenomena · Physics 2014-09-03 Wakana Iwakami , Hiroki Nagakura , Shoichi Yamada

The relevance of the standing accretion shock instability (SASI) compared to neutrino-driven convection in three-dimensional (3D) supernova-core environments is still highly controversial. Studying a 27 Msun progenitor, we demonstrate, for…

Solar and Stellar Astrophysics · Physics 2015-06-15 F. Hanke , B. Mueller , A. Wongwathanarat , A. Marek , H. -Th. Janka

In the collapsing core of massive stars, the standing accretion shock instability (SASI) can drive spiral modes that efficiently redistribute angular momentum. This process can impart a spin to the forming neutron star even when the…

Solar and Stellar Astrophysics · Physics 2015-06-17 Jérôme Guilet , Rodrigo Fernández

We investigate the effect of dimensionality on the transition to explosion in neutrino-driven core-collapse supernovae. Using parameterized hydrodynamic simulations of the stalled supernova shock in one-, two- (2D), and three spatial…

High Energy Astrophysical Phenomena · Physics 2015-08-06 Rodrigo Fernández

We examine the stability of a standing shock wave within a spherical accretion flow onto a gravitating star, in the context of core-collapse supernova explosions. Our focus is on the effect of nuclear dissociation below the shock on the…

Astrophysics · Physics 2010-01-15 Rodrigo Fernández , Christopher Thompson

The neutrino-driven explosion mechanism for core-collapse supernovae in its modern flavor relies on the additional support of hydrodynamical instabilities in achieving shock revival. Two possible candidates, convection and the so-called…

Solar and Stellar Astrophysics · Physics 2015-06-05 B. Mueller , H. -Th. Janka , A. Heger

We analyzed the growth of non-spherical perturbations in supersonic accretion flows. We have in mind the application to the post-bounce phase of core-collapse supernovae (CCSNe). Such non-spherical perturbations have been suggested by a…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Kazuya Takahashi , Shoichi Yamada
‹ Prev 1 2 3 10 Next ›