Abstract.
Matter in neutron star collisions reaches densities up to few times the nuclear saturation threshold, \(\rho_0\) and temperatures up to one hundred MeV. Understanding the structure and composition of such matter requires many-body non-perturbative calculations that are currently highly uncertain. Unique constraints on the neutron star matter are provided by gravitational-wave observations aided by numerical relativity simulations. In this work, we explore the thermodynamical conditions of matter along the merger dynamics. We consider 3 microphysical equations of state and numerical relativity simulations including approximate neutrino transport. The neutron star cores collision and their multiple bounces heat the initially cold matter to several tens of MeV. Streams of hot matter with initial densities \(\sim 1 - 2\rho_{0}\) move outwards and cool due to decompression and neutrino emission. The merger can result in a neutron star remnant with densities up to \( 3 -5\rho_{0}\) and temperatures \( \sim 50\) MeV. The highest temperatures are confined in an approximately spherical annulus at densities \( \sim\rho_0\). Such temperatures favour positron-neutron capture thus leading to a neutrino emission dominated by electron antineutrinos. We study the impact of trapped neutrinos on the remnant matter’s pressure, electron fraction and temperature and find that it has a negligible effect. Disks around neutron star or black hole remnant are neutron rich and not isentropic, but they differ in size, entropy and lepton fraction depending on the nature of the central object. In the presence of a black hole, disks are smaller and mostly transparent to neutrinos; in presence of a massive neutron star, they are more massive, geometrically and optically thick.
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M. Shibata, K. Uryu, Phys. Rev. D 61, 064001 (2000) arXiv:gr-qc/9911058
Y. Sekiguchi, K. Kiuchi, K. Kyutoku, M. Shibata, Phys. Rev. Lett. 107, 211101 (2011) arXiv:1110.4442
S. Bernuzzi, D. Radice, C.D. Ott, L.F. Roberts, P. Moesta, F. Galeazzi, Phys. Rev. D 94, 024023 (2016) arXiv:1512.06397
D. Radice, A. Perego, K. Hotokezaka, S.A. Fromm, S. Bernuzzi, L.F. Roberts, Astrophys. J. 869, 130 (2018) arXiv:1809.11161
L.F. Roberts, G. Shen, V. Cirigliano, J.A. Pons, S. Reddy, S.E. Woosley, Phys. Rev. Lett. 108, 061103 (2012) arXiv:1112.0335
J.M. Lattimer, Annu. Rev. Nucl. Part. Sci. 62, 485 (2012) arXiv:1305.3510
F. Ozel, P. Freire, Annu. Rev. Astron. Astrophys. 54, 401 (2016) arXiv:1603.02698
M. Oertel, M. Hempel, T. Klhn, S. Typel, Rev. Mod. Phys. 89, 015007 (2017) arXiv:1610.03361
J.M. Lattimer, F.D. Swesty, Nucl. Phys. A 535, 331 (1991)
H. Shen, H. Toki, K. Oyamatsu, K. Sumiyoshi, Nucl. Phys. A 637, 435 (1998) arXiv:nucl-th/9805035
I. Bombaci, D. Logoteta, Astron. Astrophys. 609, A128 (2018) arXiv:1805.11846
T. Damour, Gravitational radiation and the motion of compact bodies, in Gravitational Radiation, edited by N. Deruelle, T. Piran (North-Holland, Amsterdam, 1983) pp. 59--144
E.E. Flanagan, T. Hinderer, Phys. Rev. D 77, 021502 (2008) arXiv:0709.1915
T. Hinderer, B.D. Lackey, R.N. Lang, J.S. Read, Phys. Rev. D 81, 123016 (2010) arXiv:0911.3535
T. Damour, A. Nagar, Phys. Rev. D 81, 084016 (2010) arXiv:0911.5041
T. Damour, A. Nagar, L. Villain, Phys. Rev. D 85, 123007 (2012) arXiv:1203.4352
S. Bernuzzi, A. Nagar, M. Thierfelder, B. Brügmann, Phys. Rev. D 86, 044030 (2012) arXiv:1205.3403
S. Bernuzzi, A. Nagar, S. Balmelli, T. Dietrich, M. Ujevic, Phys. Rev. Lett. 112, 201101 (2014) arXiv:1402.6244
F. Zappa, S. Bernuzzi, D. Radice, A. Perego, T. Dietrich, Phys. Rev. Lett. 120, 111101 (2018) arXiv:1712.04267
K. Hotokezaka, K. Kyutoku, H. Okawa, M. Shibata, K. Kiuchi, Phys. Rev. D 83, 124008 (2011) arXiv:1105.4370
A. Bauswein, T. Baumgarte, H.T. Janka, Phys. Rev. Lett. 111, 131101 (2013) arXiv:1307.5191
D. Radice, A. Perego, F. Zappa, S. Bernuzzi, Astrophys. J. 852, L29 (2018) arXiv:1711.03647
D. Radice, A. Perego, S. Bernuzzi, B. Zhang, Mon. Not. R. Astron. Soc. 481, 3670 (2018) arXiv:1803.10865
D. Eichler, M. Livio, T. Piran, D.N. Schramm, Nature 340, 126 (1989)
E. Nakar, Phys. Rep. 442, 166 (2007) arXiv:astro-ph/0701748
S. Rosswog, Int. J. Mod. Phys. D 24, 1530012 (2015) arXiv:1501.02081
O. Just, M. Obergaulinger, H.T. Janka, A. Bauswein, N. Schwarz, Astrophys. J. 816, L30 (2016) arXiv:1510.04288
D. Radice, S. Bernuzzi, W. Del Pozzo, L.F. Roberts, C.D. Ott, Astrophys. J. 842, L10 (2017) arXiv:1612.06429
E.R. Most, L.J. Papenfort, V. Dexheimer, M. Hanauske, S. Schramm, H. Stcker, L. Rezzolla, arXiv:1807.03684 (2018)
A. Bauswein, N.U.F. Bastian, D.B. Blaschke, K. Chatziioannou, J.A. Clark, T. Fischer, M. Oertel, Phys. Rev. Lett. 122, 061102 (2019) arXiv:1809.01116
Virgo, LIGO Scientific Collaborations (B.P. Abbott et al.), Phys. Rev. Lett. 119, 161101 (2017) arXiv:1710.05832
LIGO Scientific, Virgo Collaborations (B.P. Abbott et al.), Phys. Rev. X 9, 011001 (2019) arXiv:1805.11579
LIGO Scientific, Virgo Collaborations (B.P. Abbott et al.), Phys. Rev. Lett. 121, 161101 (2018) arXiv:1805.11581
S. De, D. Finstad, J.M. Lattimer, D.A. Brown, E. Berger, C.M. Biwer, arXiv:1804.08583 (2018)
L. Baiotti, T. Damour, B. Giacomazzo, A. Nagar, L. Rezzolla, Phys. Rev. D 84, 024017 (2011) arXiv:1103.3874
D. Radice, L. Rezzolla, F. Galeazzi, Mon. Not. R. Astron. Soc. 437, L46 (2014) arXiv:1306.6052
K. Hotokezaka, K. Kyutoku, H. Okawa, M. Shibata, Phys. Rev. D 91, 064060 (2015) arXiv:1502.03457
A. Nagar et al., Phys. Rev. D 98, 104052 (2018) arXiv:1806.01772
Virgo, LIGO Scientific Collaborations (B.P. Abbott et al.), Astrophys. J. 851, L16 (2017) arXiv:1710.09320
A. Bauswein, H.T. Janka, Phys. Rev. Lett. 108, 011101 (2012) arXiv:1106.1616
K. Takami, L. Rezzolla, L. Baiotti, Phys. Rev. Lett. 113, 091104 (2014) arXiv:1403.5672
S. Bernuzzi, T. Dietrich, A. Nagar, Phys. Rev. Lett. 115, 091101 (2015) arXiv:1504.01764
H. Yang, V. Paschalidis, K. Yagi, L. Lehner, F. Pretorius, N. Yunes, arXiv:1707.00207 (2017)
K. Chatziioannou, J.A. Clark, A. Bauswein, M. Millhouse, T.B. Littenberg, N. Cornish, Phys. Rev. D 96, 124035 (2017) arXiv:1711.00040
B. Margalit, B.D. Metzger, Astrophys. J. 850, L19 (2017) arXiv:1710.05938
M. Shibata, S. Fujibayashi, K. Hotokezaka, K. Kiuchi, K. Kyutoku, Y. Sekiguchi, M. Tanaka, Phys. Rev. D 96, 123012 (2017) arXiv:1710.07579
L. Rezzolla, E.R. Most, L.R. Weih, Astrophys. J. 852, L25 (2018) arXiv:1711.00314
M. Ruiz, S.L. Shapiro, A. Tsokaros, Phys. Rev. D 97, 021501 (2018) arXiv:1711.00473
A. Bauswein, O. Just, H.T. Janka, N. Stergioulas, Astrophys. J. 850, L34 (2017) arXiv:1710.06843
D. Radice, L. Dai, Eur. Phys. J. A 55, 50 (2019) arXiv:1810.12917
S. Typel, G. Ropke, T. Klahn, D. Blaschke, H.H. Wolter, Phys. Rev. C 81, 015803 (2010) arXiv:0908.2344
M. Hempel, J. Schaffner-Bielich, Nucl. Phys. A 837, 210 (2010) arXiv:0911.4073
A.W. Steiner, M. Hempel, T. Fischer, Astrophys. J. 774, 17 (2013) arXiv:1207.2184
K. Hebeler, J.M. Lattimer, C.J. Pethick, A. Schwenk, Astrophys. J. 773, 11 (2013) arXiv:1303.4662
P. Demorest, T. Pennucci, S. Ransom, M. Roberts, J. Hessels, Nature 467, 1081 (2010) arXiv:1010.5788
J. Antoniadis, P.C. Freire, N. Wex, T.M. Tauris, R.S. Lynch et al., Science 340, 6131 (2013) arXiv:1304.6875
Eric Gourgoulhon, Philippe Grandclément, Jean-Alain Marck, Jérôme Novak and Keisuke Taniguchi, http://www.lorene.obspm.fr/, Paris Observatory, Meudon section - LUTH laboratory
S. Bernuzzi, D. Hilditch, Phys. Rev. D 81, 084003 (2010) arXiv:0912.2920
D. Hilditch, S. Bernuzzi, M. Thierfelder, Z. Cao, W. Tichy, B. Bruegmann, Phys. Rev. D 88, 084057 (2013) arXiv:1212.2901
D. Radice, L. Rezzolla, Astron. Astrophys. 547, A26 (2012) arXiv:1206.6502
D. Radice, L. Rezzolla, F. Galeazzi, Class. Quantum. Grav. 31, 075012 (2014) arXiv:1312.5004
D. Radice, L. Rezzolla, F. Galeazzi, ASP Conf. Ser. 498, 121 (2015) arXiv:1502.00551
M.J. Berger, J. Oliger, J. Comput. Phys. 53, 484 (1984)
M.J. Berger, P. Colella, J. Comput. Phys. 82, 64 (1989)
C. Reisswig, R. Haas, C.D. Ott, E. Abdikamalov, P. Mösta, D. Pollney, E. Schnetter, Phys. Rev. D 87, 064023 (2013) arXiv:1212.1191
E. Schnetter, S.H. Hawley, I. Hawke, Class. Quantum. Grav. 21, 1465 (2004) arXiv:gr-qc/0310042
D. Radice, Astrophys. J. 838, L2 (2017) arXiv:1703.02046
N.I. Shakura, R.A. Sunyaev, Astron. Astrophys. 24, 337 (1973)
K. Kiuchi, K. Kyutoku, Y. Sekiguchi, M. Shibata, Phys. Rev. D 97, 124039 (2018) arXiv:1710.01311
S. Rosswog, M. Liebendoerfer, Mon. Not. R. Astron. Soc. 342, 673 (2003) arXiv:astro-ph/0302301
N. Itoh, H. Hayashi, A. Nishikawa, Y. Kohyama, Astrophys. J. Suppl. 102, 411 (1996)
F. Galeazzi, W. Kastaun, L. Rezzolla, J.A. Font, Phys. Rev. D 88, 064009 (2013) arXiv:1306.4953
D. Radice, F. Galeazzi, J. Lippuner, L.F. Roberts, C.D. Ott, L. Rezzolla, Mon. Not. R. Astron. Soc. 460, 3255 (2016) arXiv:1601.02426
S.W. Bruenn, Astrophys. J. Suppl. 58, 771 (1985)
M.H. Ruffert, H.T. Janka, G. Schäfer, Astron. Astrophys. 311, 532 (1996) arXiv:astro-ph/9509006
A. Burrows, S. Reddy, T.A. Thompson, Nucl. Phys. A 777, 356 (2006) arXiv:astro-ph/0404432
S.L. Shapiro, S.A. Teukolsky, Black holes, white dwarfs, and neutron stars: The physics of compact objects (Wiley, New York, USA, 1983)
D. Neilsen, S.L. Liebling, M. Anderson, L. Lehner, E. O’Connor et al., Phys. Rev. D 89, 104029 (2014) arXiv:1403.3680
Y. Sekiguchi, K. Kiuchi, K. Kyutoku, M. Shibata, Phys. Rev. D 91, 064059 (2015) arXiv:1502.06660
F. Foucart, E. O’Connor, L. Roberts, M.D. Duez, R. Haas, L.E. Kidder, C.D. Ott, H.P. Pfeiffer, M.A. Scheel, B. Szilagyi, Phys. Rev. D 91, 124021 (2015) arXiv:1502.04146
F. Foucart, M.D. Duez, L.E. Kidder, R. Nguyen, H.P. Pfeiffer, M.A. Scheel, arXiv:1806.02349 (2018)
A. Perego, R. Cabezon, R. Kaeppeli, Astrophys. J. Suppl. 223, 22 (2016) arXiv:1511.08519
J. Kaplan, C. Ott, E. O’Connor, K. Kiuchi, L. Roberts et al., Astrophys. J. 790, 19 (2014) arXiv:1306.4034
K. Hotokezaka, K. Kiuchi, K. Kyutoku, H. Okawa, Y.i. Sekiguchi et al., Phys. Rev. D 87, 024001 (2013) arXiv:1212.0905
A. Bauswein, S. Goriely, H.T. Janka, Astrophys. J. 773, 78 (2013) arXiv:1302.6530
N. Stergioulas, A. Bauswein, K. Zagkouris, H.T. Janka, Mon. Not. R. Astron. Soc. 418, 427 (2011) arXiv:1105.0368
S. Bernuzzi, T. Dietrich, W. Tichy, B. Brügmann, Phys. Rev. D 89, 104021 (2014) arXiv:1311.4443
S. Bacca, K. Hally, M. Liebendorfer, A. Perego, C.J. Pethick, A. Schwenk, Astrophys. J. 758, 34 (2012) arXiv:1112.5185
T. Fischer, M. Hempel, I. Sagert, Y. Suwa, J. Schaffner-Bielich, Eur. Phys. J. A 50, 46 (2014) arXiv:1307.6190
S. Lalit, M.A.A. Mamun, C. Constantinou, M. Prakash, Eur. Phys. J. A 55, 10 (2019) arXiv:1809.08126
A. Perego, S. Rosswog, R. Cabezon, O. Korobkin, R. Kaeppeli et al., Mon. Not. R. Astron. Soc. 443, 3134 (2014) arXiv:1405.6730
W. Kastaun, R. Ciolfi, A. Endrizzi, B. Giacomazzo, Phys. Rev. D 96, 043019 (2017) arXiv:1612.03671
M. Hanauske, K. Takami, L. Bovard, L. Rezzolla, J.A. Font, F. Galeazzi, H. Stcker, Phys. Rev. D 96, 043004 (2017) arXiv:1611.07152
J.P. Cox, R.T. Giuli, Principles of stellar structure (Gordon and Breach, New York, 1968)
K. Takahashi, M.F. El Eid, W. Hillebrandt, Astron. Astrophys. 67, 185 (1978)
S. Banik, M. Hempel, D. Bandyopadhyay, Astrophys. J. Suppl. 214, 22 (2014) arXiv:1404.6173
N.K. Glendenning, Compact Stars (Springer-Verlag, New York, 1996)
B.D. Metzger, R. Fernndez, Mon. Not. R. Astron. Soc. 441, 3444 (2014) arXiv:1402.4803
O. Just, A. Bauswein, R.A. Pulpillo, S. Goriely, H.T. Janka, Mon. Not. R. Astron. Soc. 448, 541 (2015) arXiv:1406.2687
F. Foucart, E. O’Connor, L. Roberts, L.E. Kidder, H.P. Pfeiffer, M.A. Scheel, Phys. Rev. D 94, 123016 (2016) arXiv:1607.07450
J. Lippuner, R. Fernndez, L.F. Roberts, F. Foucart, D. Kasen, B.D. Metzger, C.D. Ott, Mon. Not. R. Astron. Soc. 472, 904 (2017) arXiv:1703.06216
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Perego, A., Bernuzzi, S. & Radice, D. Thermodynamics conditions of matter in neutron star mergers. Eur. Phys. J. A 55, 124 (2019). https://doi.org/10.1140/epja/i2019-12810-7
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DOI: https://doi.org/10.1140/epja/i2019-12810-7