اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدRuling out the supersoft high-density symmetry energy from the discovery of PSR J0740+6620 with mass $2.14^{+0.10}_{-0.09}M_odot$
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Using the very recently reported mass $2.14^{+0.10}_{-0.09}M_odot$ of PSR J0740+6620 together with the data of finite nuclei and the constraints on the equation of state of symmetric nuclear matter at suprasaturation densities from flow data in heavy-ion collisions, we show that the symmetry energy $E_{rm sym}(n)$ cannot be supersoft so that it becomes negative at suprasaturation densities in neutron stars (NSs) and thus may make the NS have a pure neutron matter core. This is in contrast to the fact that using the mass $2.01 pm 0.04 M_odot$ of PSR J0348+0432 as the NS maximum mass cannot rule out the supersoft high-density $E_{rm sym}(n)$. Furthermore, we find the stiffer high-density $E_{rm sym}(n)$ based on the existence of $2.14M_odot$ NSs leads to a strong constraint of $Lambda_{1.4} ge 348^{+88}_{-51}$ for the dimensionless tidal deformability of the canonical $1.4M_odot$ NS.
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