magnetars as cooling neutron stars with internal heating
DESCRIPTION
MAGNETARS AS COOLING NEUTRON STARS WITH INTERNAL HEATING. A.D. Kaminker , D.G. Yakovlev, A.Y. Potekhin, N. Shibazaki*, P. Sternin, and O.Y. Gnedin**. Ioffe Physical Technical Institute, St.-Petersburg, Russia *Rikkyo University, Tokyo 171-8501, Japan - PowerPoint PPT PresentationTRANSCRIPT
MAGNETARS AS COOLING NEUTRON STARS WITHMAGNETARS AS COOLING NEUTRON STARS WITH INTERNAL HEATINGINTERNAL HEATING
A.D. Kaminker, D.G. Yakovlev, A.Y. Potekhin, N. Shibazaki*, P. Sternin, and O.Y. Gnedin**
Ioffe Physical Technical Institute, St.-Petersburg, Russia*Rikkyo University, Tokyo 171-8501, Japan **Ohio State University, 760 1/2 Park Street, Columbus, OH 43215, USA
Conclusions
Introduction
Physics input
Games with cooling code
)(TTT ss
Thermal balance:
Photon luminosity:
Heat blanketingenvelope:
ergsTUT2
94810~Heat content:
Cooling theory with internal heating
Main cooling regulators:
1. EOS2. Neutrino emission3. Reheating processes4. Superfluidity5. Magnetic fields6. Light elements on the surface
42L 4 sR T
Heat transport:
( )dT
C T W L Ldt
;dT
Fdr
- effective thermal conductivity
1. EOS: APR III (n, p, e, µ) Gusakov et al. (2005) Akmal-Pandharipande-Ravenhall (1998) -- neutron star models
Parametrization: Heiselberg & Hiorth-Jensen (1999)
2. Heat blanketing envelope: 310 /10 cmgb
sb TT -- relation;
)(sT surface temperature,
;4442 dTLTR seff
effT -- effective temperature;
d -- surface element
( )b bT T
1- SGR 1900+14
2- SGR 0526-66
3- AXP 1E 1841-045
4- AXP 1RXS J170849-400910
5- AXP 4U 0142+61
6- AXP 1E 2259+586
21
H
H0
3. Model of heating:
)exp(1
1)(
2
22
f;)exp(1
1)(
1
11
f at
)exp(),( 210 t
ffHtH
21
10 11 31 23 10 ; 10 ;g cm i
12 12 31 210 ; 3 10 ;g cm ii
13 14 31 23 10 ; 10 ;g cm iii
14 32 ; =9 10 ;g cm iv
No isothermal stage
Core — crust decoupling
yrt 310 1- SGR 1900+14
2- SGR 0526-66
3- AXP 1E 1841-045
4- AXP 1RXS J170849-400910
5- AXP 4U 0142+61
6- AXP 1E 2259+586Only outer layers of heating are appropriate for hottest NSs
Necessary energy input vrs. photon luminosity
)(s
erg into the layer W 1 2
Direct Urca process included
Enchanced thermal conductivity
Appearance of isothermal layers
from min to max
Conclusions
1. High thermal state of magnetars demand a powerful reheating
2. The heating should be located in a thin layer at :11 35 10 g cm
in the outer crust. The heat intensity 0H should range
from 19 3 10 to 20 3 13 10 erg cm s Deeper heating would be extremely inefficient due to neutrino radiation
4. Pumping huge energy into deeper layers can not increase -- effT
5.
.
Temperature distributions within NS are strongly nonuniform due to
thermal decoupling of the outer crust from the inner parts of the star
3. Only ~ 1% of the total energy released in the heat layer can be spent to heat the NS surface