Cooling neutron star in the Cassiopeia A supernova remnant: evidence for superfluidity in the core
Cooling neutron star in the Cassiopeia A supernova remnant: evidence for superfluidity in the core
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DOI：
10.1111/j.1745-3933.2011.01015.x
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发表时间：
2010-11
影响因子：
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通讯作者：
P. Shternin;D. Yakovlev;C. Heinke;W. Ho;D. Patnaude
中科院分区：
文献类型：
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作者：
P. Shternin;D. Yakovlev;C. Heinke;W. Ho;D. Patnaude
根据Ho和Heinke最近的研究结果，仙后座A超新星遗迹包含一个年轻的(？中子星（NS），具有碳大气，表面有效温度明显下降。我们报告了一项新的（2010年11月）钱德拉观测结果，证实了之前报道的下降率。如果中子最近在NS核心中成为超流体（处于三重态），由于库珀对形成（CPF）过程而产生中微子发射飞溅，则可以自然地解释这种下降，该过程目前加速了冷却。这种情况对NS核鲜为人知的性质提出了严格的限制：对于中子超流动性开始的温度Tcn（?）的密度依赖[Tcn（?）应该有一个宽峰，最大？（7-9） × 108 k]；超流体物质集体效应对CPF过程的还原因子q （q > 0.4）和中子超流体开始前的中微子发射强度（比标准修正Urca过程弱30-100倍）的影响。这是核子超流动性的重要证据，来自冷却核子核的观测
According to recent results of Ho & Heinke, the Cassiopeia A supernova remnant contains a young (?330-yr-old) neutron star (NS) which has carbon atmosphere and shows notable decline of the effective surface temperature. We report a new (2010 November) Chandra observation which confirms the previously reported decline rate. The decline is naturally explained if neutrons have recently become superfluid (in triplet state) in the NS core, producing a splash of neutrino emission due to Cooper pair formation (CPF) process that currently accelerates the cooling. This scenario puts stringent constraints on poorly known properties of NS cores: on density dependence of the temperature Tcn(?) for the onset of neutron superfluidity [Tcn(?) should have a wide peak with maximum ? (7–9) × 108 K]; on the reduction factor q of CPF process by collective effects in superfluid matter (q > 0.4) and on the intensity of neutrino emission before the onset of neutron superfluidity (30–100 times weaker than the standard modified Urca process). This is serious evidence for nucleon superfluidity in NS cores that comes from observations of cooling NSs