Abstract
The merger of binary neutron stars (BNSs) can lead to large amplifications of the magnetic field due to the development of turbulence and instabilities in the fluid, such as the Kelvin'Helmholtz shear instability, which drive small-scale dynamo activity. In order to properly resolve such instabilities and obtain the correct magnetic field amplification, one would need to employ resolutions that are currently unfeasible in global general relativistic magnetohydrodynamic simulations of BNS mergers. Here, we present a subgrid model that allows global simulations to take into account the small-scale amplification of the magnetic field which is caused by the development of turbulence during BNS mergers. Assuming dynamo saturation, we show that magnetar-level fields (∼1016 G) can be easily reached, and should therefore be expected from the merger of magnetized BNSs. The total magnetic energy can reach values up to ∼1051 erg and the post-merger remnant can therefore emit strong electromagnetic signals and possibly produce short gamma-ray bursts.
Original language | English (US) |
---|---|
Article number | 39 |
Journal | Astrophysical Journal |
Volume | 809 |
Issue number | 1 |
DOIs | |
State | Published - Aug 10 2015 |
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Keywords
- gamma-ray burst: general
- magnetohydrodynamics (MHD)
- methods: numerical
- stars: magnetars
- stars: neutron
ASJC Scopus subject areas
- Nuclear and High Energy Physics
Cite this
PRODUCING MAGNETAR MAGNETIC FIELDS IN THE MERGER OF BINARY NEUTRON STARS. / Giacomazzo, Bruno; Zrake, Jonathan; Duffell, Paul C.; Macfadyen, Andrew I.; Perna, Rosalba.
In: Astrophysical Journal, Vol. 809, No. 1, 39, 10.08.2015.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - PRODUCING MAGNETAR MAGNETIC FIELDS IN THE MERGER OF BINARY NEUTRON STARS
AU - Giacomazzo, Bruno
AU - Zrake, Jonathan
AU - Duffell, Paul C.
AU - Macfadyen, Andrew I.
AU - Perna, Rosalba
PY - 2015/8/10
Y1 - 2015/8/10
N2 - The merger of binary neutron stars (BNSs) can lead to large amplifications of the magnetic field due to the development of turbulence and instabilities in the fluid, such as the Kelvin'Helmholtz shear instability, which drive small-scale dynamo activity. In order to properly resolve such instabilities and obtain the correct magnetic field amplification, one would need to employ resolutions that are currently unfeasible in global general relativistic magnetohydrodynamic simulations of BNS mergers. Here, we present a subgrid model that allows global simulations to take into account the small-scale amplification of the magnetic field which is caused by the development of turbulence during BNS mergers. Assuming dynamo saturation, we show that magnetar-level fields (∼1016 G) can be easily reached, and should therefore be expected from the merger of magnetized BNSs. The total magnetic energy can reach values up to ∼1051 erg and the post-merger remnant can therefore emit strong electromagnetic signals and possibly produce short gamma-ray bursts.
AB - The merger of binary neutron stars (BNSs) can lead to large amplifications of the magnetic field due to the development of turbulence and instabilities in the fluid, such as the Kelvin'Helmholtz shear instability, which drive small-scale dynamo activity. In order to properly resolve such instabilities and obtain the correct magnetic field amplification, one would need to employ resolutions that are currently unfeasible in global general relativistic magnetohydrodynamic simulations of BNS mergers. Here, we present a subgrid model that allows global simulations to take into account the small-scale amplification of the magnetic field which is caused by the development of turbulence during BNS mergers. Assuming dynamo saturation, we show that magnetar-level fields (∼1016 G) can be easily reached, and should therefore be expected from the merger of magnetized BNSs. The total magnetic energy can reach values up to ∼1051 erg and the post-merger remnant can therefore emit strong electromagnetic signals and possibly produce short gamma-ray bursts.
KW - gamma-ray burst: general
KW - magnetohydrodynamics (MHD)
KW - methods: numerical
KW - stars: magnetars
KW - stars: neutron
UR - http://www.scopus.com/inward/record.url?scp=84945269684&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84945269684&partnerID=8YFLogxK
U2 - 10.1088/0004-637X/809/1/39
DO - 10.1088/0004-637X/809/1/39
M3 - Article
AN - SCOPUS:84945269684
VL - 809
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 1
M1 - 39
ER -