Descalarization bursts from Galactic supramassive neutron stars: a kHz continuous-wave target

Author(s)

M., José Carlos Olvera, Doneva, Daniela D., Cerdá-Durán, Pablo, Font, José A., Yazadjiev, Stoytcho S.

Abstract

In massive scalar-tensor gravity, a scalarized neutron star must shed its scalar hair as it collapses into a black hole. Using 3D simulations of a realistic rotating progenitor we show that dispersion stretches the emitted burst into a quasi-monochromatic signal in the kHz frequency range lasting $>10^4$ yr and amenable to continuous-wave methods. We find that detecting these signals in directed searches of supernova remnants without a central pulsar requires sensitivity depths of 233--762 $\rm{Hz^{-1/2}}$ with the A+-ET-CE detector network. We estimate up to $\sim3$ of these signals in transit at any observational epoch.

Figures

$\sqrt{S_\Phi}$ compared to the noise curves of A+, ET and CE detectors. The stars show the time needed for each frequency to reach the detectors for a source located at 8.5 kpc and a 10-month observation period. The black line represents the low-mass case $m_\Phi=3.3\times 10^{-12} \rm{eV/c^2}$ while the red one shows $m_\Phi=10^{-11}\rm{eV/c^2}$. The vertical lines mark $f_\Phi$ for each case.
Caption $\sqrt{S_\Phi}$ compared to the noise curves of A+, ET and CE detectors. The stars show the time needed for each frequency to reach the detectors for a source located at 8.5 kpc and a 10-month observation period. The black line represents the low-mass case $m_\Phi=3.3\times 10^{-12} \rm{eV/c^2}$ while the red one shows $m_\Phi=10^{-11}\rm{eV/c^2}$. The vertical lines mark $f_\Phi$ for each case.
Left: Time evolution of frequencies reaching the detector network. $t_{\rm age}$ represents the instant when the star collapses. The vertical lines represent $f_\Phi$ for each simulation. Right: Evolution of $\dot{f}(t)$ with the shaded region corresponding to $|\dot{f}|<10^{-8}\,\rm Hz\,s^{-1}$. Star symbols as in Fig.~\ref{fig:strainSF_main}.
Caption Left: Time evolution of frequencies reaching the detector network. $t_{\rm age}$ represents the instant when the star collapses. The vertical lines represent $f_\Phi$ for each simulation. Right: Evolution of $\dot{f}(t)$ with the shaded region corresponding to $|\dot{f}|<10^{-8}\,\rm Hz\,s^{-1}$. Star symbols as in Fig.~\ref{fig:strainSF_main}.
Sensitivity depth $\mathcal{D}_{\rm eq}(f)$ and Normalized Upper Limit $h_{\rm{NUL}}$ for the A+-ET-CE detector network. The color bands represent the sensitivity depth achieved by LVK all-sky \cite{Steltner:2023cfk,LVK2022,LIGOScientific:2026plm}, directed \cite{Abac2026,Ming:2025ehy} and targeted CW searches \cite{Riles:2022wwz}. The vertical lines show $f_\Phi$. The red dashed line corresponds to the high-mass case assuming an idealized single detector with $\sqrt{S_n(f>2.4\rm{\,kHz)}}=10^{-25}\,\rm{Hz^{-1/2}}$.
Caption Sensitivity depth $\mathcal{D}_{\rm eq}(f)$ and Normalized Upper Limit $h_{\rm{NUL}}$ for the A+-ET-CE detector network. The color bands represent the sensitivity depth achieved by LVK all-sky \cite{Steltner:2023cfk,LVK2022,LIGOScientific:2026plm}, directed \cite{Abac2026,Ming:2025ehy} and targeted CW searches \cite{Riles:2022wwz}. The vertical lines show $f_\Phi$. The red dashed line corresponds to the high-mass case assuming an idealized single detector with $\sqrt{S_n(f>2.4\rm{\,kHz)}}=10^{-25}\,\rm{Hz^{-1/2}}$.
Parameter space for pulsar PSR J0952-0607 in MSTT. Top and bottom panels show, respectively, the star's spin frequency and spin parameter $\chi=J/M^2$ as a function of the gravitational mass. The solid colored lines represent constant angular momentum sequences. The crosses mark the maximum gravitational mass allowed for each sequence. The shaded region and red lines give the measured mass and spin frequency of PSR J0952-0607 and their uncertainties \cite{Romani2025}. The black star represents the supramassive progenitor we evolve while the dotted magenta lines represent the evolutionary track it follows as it spins-down.
Caption Parameter space for pulsar PSR J0952-0607 in MSTT. Top and bottom panels show, respectively, the star's spin frequency and spin parameter $\chi=J/M^2$ as a function of the gravitational mass. The solid colored lines represent constant angular momentum sequences. The crosses mark the maximum gravitational mass allowed for each sequence. The shaded region and red lines give the measured mass and spin frequency of PSR J0952-0607 and their uncertainties \cite{Romani2025}. The black star represents the supramassive progenitor we evolve while the dotted magenta lines represent the evolutionary track it follows as it spins-down.
References
  • [1] The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration, arXiv e-prints , arXiv:2603.19019 (2026), arXiv:2603.19019 [gr-qc].
  • [1] The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration, arXiv e-prints , arXiv:2603.19019 (2026), arXiv:2603.19019 [gr-qc].
  • [2] The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration, arXiv e-prints , arXiv:2603.19020 (2026), arXiv:2603.19020 [gr-qc].
  • [2] The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration, arXiv e-prints , arXiv:2603.19020 (2026), arXiv:2603.19020 [gr-qc].
  • [3] The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration, arXiv e-prints , arXiv:2603.19021 (2026), arXiv:2603.19021 [gr-qc].
  • [3] The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration, arXiv e-prints , arXiv:2603.19021 (2026), arXiv:2603.19021 [gr-qc].
  • [4] A. G. Abac et al. (LIGO Scientific, VIRGO, KAGRA), arxiv (2026), arXiv:2607.19293 [gr-qc].
  • [5] P. Jordan, Zeitschrift für Physik 157, 112 (1959).
  • [6] C. Brans and R. H. Dicke, Phys. Rev. 124, 925 (1961).
  • [7] L. Heisenberg, Physics Reports 796, 1 (2019).
  • [8] B. Bertotti, L. Iess, and P. Tortora, Nature 425, 374 (2003).
  • [9] C. M. Will, Living Rev. Rel. 17, 4 (2014), arXiv:1403.7377 [gr-qc].
  • [10] P. C. C. Freire and N. Wex, Living Rev. Rel. 27, 5 (2024), arXiv:2407.16540 [gr-qc].
  • [11] J. Zhao, P. C. C. Freire, M. Kramer, L. Shao, and N. Wex, Class. Quant. Grav. 39, 11LT01 (2022), arXiv:2201.03771 [astro-ph.HE].
  • [12] H.-J. Kuan, K. Van Aelst, A. T.-L. Lam, and M. Shibata, Phys. Rev. D 108, 064057 (2023), arXiv:2309.01709 [gr-qc].
  • [13] F. M. Ramazanoğlu and F. Pretorius, Physical Review D 93, 064005 (2016).
  • [14] S. S. Yazadjiev, D. D. Doneva, and D. Popchev, Phys. Rev. D 93, 084038 (2016), arXiv:1602.04766 [gr-qc].
  • [15] T. Damour and G. Esposito-Farèse, Phys. Rev. Lett. 70, 2220 (1993).
  • [16] K. İ. Ünlütürk, S. Tuna, O. K. Yamak, and F. M. Ramazanoğlu, Phys. Rev. Lett. 135, 061401 (2025), arXiv:2502.01781 [gr-qc].
  • [17] D. D. Doneva, F. M. Ramazanoğlu, H. O. Silva, T. P. Sotiriou, and S. S. Yazadjiev, Rev. Mod. Phys. 96, 015004 (2024).
  • [18] S. S. Yazadjiev and D. D. Doneva, Int. J. Mod. Phys. D 34, 2530004 (2025), arXiv:2505.01038 [gr-qc].
  • [19] J. Novak, Phys. Rev. D 57, 4789 (1998).
  • [20] H.-J. Kuan, D. D. Doneva, and S. S. Yazadjiev, Phys. Rev. Lett. 127, 161103 (2021), arXiv:2103.11999 [gr-qc].
  • [21] A. T.-L. Lam, H.-J. Kuan, M. Shibata, K. Van Aelst, and K. Kiuchi, Phys. Rev. D 110, 104018 (2024).
  • [22] J. C. Olvera M., D. D. Doneva, P. Cerdá-Durán, J. A. Font, and S. S. Yazadjiev, Phys. Rev. D 114, 024052 (2026).
  • [23] A. Nishizawa, A. Taruya, K. Hayama, S. Kawamura, and M.-a. Sakagami, Phys. Rev. D 79, 082002 (2009).
  • [24] U. Sperhake, C. J. Moore, R. Rosca, M. Agathos, D. Gerosa, and C. D. Ott, Phys. Rev. Lett. 119, 201103 (2017), arXiv:1708.03651 [gr-qc].
  • [25] R. Rosca-Mead, U. Sperhake, C. J. Moore, M. Agathos, D. Gerosa, and C. D. Ott, Physical Review D 102, 044010 (2020).
  • [26] D. Huang, C.-Q. Geng, and H.-J. Kuan, Classical and Quantum Gravity 38, 245006 (2021).
  • [27] N. Asakawa and Y. Sekiguchi, Phys. Rev. D 108, 044060 (2023), arXiv:2308.15052 [gr-qc].
  • [28] R. Rosca-Mead, C. J. Moore, M. Agathos, and U. Sperhake, Class. Quant. Grav. 36, 134003 (2019), arXiv:1903.09704 [gr-qc].
  • [29] P. C.-K. Cheong and T. G. F. Li, Phys. Rev. D 100, 024027 (2019).
  • [30] C.-Q. Geng, H.-J. Kuan, and L.-W. Luo, Eur. Phys. J. C 80, 780 (2020), arXiv:2005.11629 [gr-qc].
  • [31] B. P. Abbott et al. (LIGO Scientific, Virgo), Astrophys. J. Lett. 851, L16 (2017), arXiv:1710.09320 [astroph.HE].
  • [32] K. G. Arun et al. (LISA), Living Rev. Rel. 25, 4 (2022), arXiv:2205.01597 [gr-qc].
  • [33] S. Hild et al., Classical and Quantum Gravity 28, 094013 (2011).
  • [34] A. Abac et al. (ET), JCAP 03, 081, arXiv:2503.12263 [gr-qc].
  • [35] V. Srivastava, D. Davis, K. Kuns, P. Landry, S. Ballmer, M. Evans, E. D. Hall, J. Read, and B. S. Sathyaprakash, The Astrophysical Journal 931, 22 (2022).
  • [36] N. Aggarwal, O. D. Aguiar, D. Blas, A. Bauswein, G. Cella, S. Clesse, A. M. Cruise, V. Domcke, S. Ellis, D. G. Figueroa, G. Franciolini, C. Garcı́a-Cely, A. Geraci, M. Goryachev, H. Grote, M. Hindmarsh, A. Ito, J. Kopp, S. M. Lee, K. Martineau, J. McDonald, F. Muia, N. Mukund, D. Ottaway, M. Peloso, K. Peters, F. Quevedo, A. Ricciardone, A. Ringwald, J. Steinlechner, S. Steinlechner, S. Sun, C. Tamarit, M. E. Tobar, F. Torrenti, C. Ünal, and G. White, Living Reviews in Relativity 28, 10 (2025), arXiv:2501.11723 [gr-qc].
  • [37] K. Wette, Astropart. Phys. 153, 102880 (2023), [Erratum: Astropart.Phys. 179, 103229 (2026)], arXiv:2305.07106 [gr-qc].
  • [37] K. Wette, Astropart. Phys. 153, 102880 (2023), [Erratum: Astropart.Phys. 179, 103229 (2026)], arXiv:2305.07106 [gr-qc].
  • [38] K. Riles, Living Rev. Rel. 26, 3 (2023), arXiv:2206.06447 [astro-ph.HE].
  • [39] C. Dreissigacker, R. Prix, and K. Wette, Phys. Rev. D 98, 084058 (2018), arXiv:1808.02459 [gr-qc].
  • [40] B. Behnke, M. A. Papa, and R. Prix, Phys. Rev. D 91, 064007 (2015).
  • [41] B. Steltner, M. A. Papa, H. B. Eggenstein, R. Prix, M. Bensch, B. Allen, and B. Machenschalk, Astrophys. J. 952, 55 (2023), arXiv:2303.04109 [gr-qc].
  • [42] R. Abbott et al. (LIGO Scientific Collaboration, Virgo Collaboration, and KAGRA Collaboration), Phys. Rev. D 106, 102008 (2022).
  • [43] A. G. Abac et al. (LIGO Scientific, VIRGO, KAGRA), arxiv (2026), arXiv:2603.14168 [gr-qc].
  • [44] R. W. Romani, D. Kandel, A. V. Filippenko, T. G. Brink, and W. Zheng, The Astrophysical Journal Letters 934, L17 (2022).
  • [45] R. W. Romani, M. Beleznay, A. V. Filippenko, T. G. Brink, and W. Zheng, The Astrophysical Journal 996, 101 (2025).
  • [46] D. D. Doneva, S. S. Yazadjiev, N. Stergioulas, and K. D. Kokkotas, Phys. Rev. D 88, 084060 (2013).
  • [47] J. Ming, M. A. Papa, H.-B. Eggenstein, B. Machenschalk, J. Martins, B. Steltner, B. McGloughlin, V. Dergachev, R. Prix, and M. Bensch, Astrophys. J. 1004, 65 (2026), arXiv:2512.15672 [gr-qc].
  • [48] A. G. Abac and others (The LIGO Scientific Collaboration, The Astrophysical Journal 1004, 204 (2026).
  • [49] R. Abbott et al., The Astrophysical Journal 921, 80 (2021).
  • [50] T. Damour and G. Esposito-Farese, Classical and Quantum Gravity 9, 2093 (1992).
  • [51] A. Batrakov, H. Hu, N. Wex, P. C. Freire, V. V. Krishnan, M. Kramer, Y. J. Guo, L. Guillemot, J. W. McKee, I. Cognard, and G. Theureau, Astronomy & Astrophysics 686, A101 (2024).
  • [52] T. Damour and G. Esposito-Farèse, Phys. Rev. D 54, 1474 (1996).
  • [53] E. M. Sänger, S. Roy, M. Agathos, O. Birnholtz, A. Buonanno, T. Dietrich, M. Haney, F.-L. Julié, G. Pratten, J. Steinhoff, C. Van Den Broeck, S. Biscoveanu, P. Char, A. Heffernan, P. Joshi, A. Kedia, R. M. S. Schofield, M. Trevor, and M. Zevin, Phys. Rev. D 113, 084070 (2026).
  • [54] R. Niu, X. Zhang, B. Wang, and W. Zhao, Astrophys. J. 921, 149 (2021), arXiv:2105.13644 [gr-qc].
  • [55] J. Alsing, E. Berti, C. M. Will, and H. Zaglauer, Phys. Rev. D 85, 064041 (2012), arXiv:1112.4903 [gr-qc].
  • [56] B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration), Phys. Rev. X 9, 011001 (2019).
  • [57] J. L. Friedman, J. R. Ipser, and R. D. Sorkin, ApJ 325, 722 (1988).
  • [58] K.-i. Nakao, T. Harada, M. Shibata, S. Kawamura, and T. Nakamura, Phys. Rev. D 63, 082001 (2001).
  • [59] J. Miller, L. Barsotti, S. Vitale, P. Fritschel, M. Evans, and D. Sigg, Phys. Rev. D 91, 062005 (2015), arXiv:1410.5882 [astro-ph.IM].
  • [60] K. Ackley et al., Publ. Astron. Soc. Austral. 37, e047 (2020), arXiv:2007.03128 [astro-ph.HE].
  • [61] H. Falcke and L. Rezzolla, Astronomy & Astrophysics 562, A137 (2014).
  • [62] V. Ravi and P. D. Lasky, Monthly Notices of the Royal Astronomical Society 441, 2433 (2014).
  • [63] C. D. Dermer and A. Atoyan, The Astrophysical Journal 643, 13 (2006).
  • [64] J. A. Pons, S. Reddy, M. Prakash, J. M. Lattimer, and J. A. Miralles, The Astrophysical Journal 513, 780 (1999).
  • [65] A. Burrows and J. M. Lattimer, Astrophys. J. 307, 178 (1986).
  • [66] E. O’Connor and C. D. Ott, The Astrophysical Journal 730, 70 (2011).
  • [67] T. Sukhbold, T. Ertl, S. E. Woosley, J. M. Brown, and H.-T. Janka, The Astrophysical Journal 821, 38 (2016).
  • [68] J. M. M. Neustadt, C. S. Kochanek, K. Z. Stanek, C. Basinger, T. Jayasinghe, C. T. Garling, S. M. Adams, and J. Gerke, Monthly Notices of the Royal Astronomical Society 508, 516 (2021), https://academic.oup.com/mnras/articlepdf/508/1/516/40440715/stab2605.pdf.
  • [69] J. Antoniadis, T. M. Tauris, F. Ozel, E. Barr, D. J. Champion, and P. C. C. Freire, arXiv e-prints (2016), arXiv:1605.01665 [astro-ph.HE].
  • [70] D. L. Kaplan, D. A. Frail, B. M. Gaensler, E. V. Gotthelf, S. R. Kulkarni, P. O. Slane, and A. Nechita, Astrophys. J. Suppl. 153, 269 (2004), arXiv:astroph/0403313.
  • [71] D. L. Kaplan, B. M. Gaensler, S. R. Kulkarni, and P. O. Slane, Astrophys. J. Suppl. 163, 344 (2006), arXiv:astro-ph/0602312.
  • [72] A. Preite Martinez, Astronomy & Astrophysics 527, A55 (2011).
  • [73] R. A. Fesen, K. E. Weil, I. Cisneros, W. P. Blair, and J. C. Raymond, Mon. Not. Roy. Astron. Soc. 507, 244 (2021), arXiv:2109.05368 [astro-ph.HE].
  • [74] S. Katsuda, M. Tanaka, T. Morokuma, R. Fesen, and D. Milisavljevic, Astrophys. J. 826, 108 (2016), arXiv:1605.07271 [astro-ph.HE].
  • [75] R. Kobashi, H. Yasuda, and S.-H. Lee, Astrophys. J. 936, 26 (2022), arXiv:2207.06203 [astro-ph.HE].
  • [76] C. Ecker, M. Giliberti, and L. Rezzolla, arxiv (2026), arXiv:2609.29761 [gr-qc].
  • [77] H. J. Kuan, A. G. Suvorov, D. D. Doneva, and S. S. Yazadjiev, Physical Review Letters 129, 121104 (2022).
  • [78] S. Typel, G. Röpke, T. Klähn, D. Blaschke, and H. H. Wolter, Phys. Rev. C 81, 015803 (2010).
  • [79] M. Fortin, A. R. Raduta, S. Avancini, and C. Providência, Phys. Rev. D 101, 034017 (2020), arXiv:2001.08036 [hep-ph].
  • [80] A. T.-L. Lam, K. V. Staykov, H.-J. Kuan, D. D. Doneva, and S. S. Yazadjiev, Phys. Rev. D 111, 104030 (2025).
  • [81] H. Komatsu, Y. Eriguchi, and I. Hachisu, Monthly Notices of the Royal Astronomical Society 237, 355 (1989).
  • [82] H. Komatsu, Y. Eriguchi, I. Hachisu, H. Komatsu, Y. Eriguchi, and I. Hachisu, MNRAS 239, 153 (1989).
  • [83] N. Stergioulas and J. L. Friedman, The Astrophysical Journal 444, 306 (1995).
  • [84] M. Rizzo et al., The Einstein Toolkit (2025).
  • [85] C. Bona, J. Massó, E. Seidel, and J. Stela, Phys. Rev. Lett. 75, 600 (1995).
  • [86] M. Alcubierre, B. Brügmann, P. Diener, M. Koppitz, D. Pollney, E. Seidel, and R. Takahashi, Physical Review D 67, 084023 (2003).
  • [87] S. Cupp, L. R. Werneck, T. P. Jacques, S. Tootle, and Z. B. Etienne, Phys. Rev. D , (2026).
  • [88] P. Colella and P. R. Woodward, Journal of Computational Physics 54, 174 (1984).
  • [89] E. F. Toro, Riemann Solvers and Numerical Methods for Fluid Dynamics, 3rd ed. (Springer-Verlag Berlin Heidelberg, 2009).
  • [90] C. Palenzuela, S. L. Liebling, D. Neilsen, L. Lehner, O. L. Caballero, E. O’Connor, and M. Anderson, Phys. Rev. D 92, 044045 (2015), arXiv:1505.01607 [gr-qc].
  • [91] B. Gustafsson, H. Kreiss, and J. Oliger, References, in Time-Dependent Problems and Difference Methods (John Wiley & Sons, Ltd, 2013) pp. 499–505.
  • [92] K. Rozwadowska, F. Vissani, and E. Cappellaro, New Astronomy 83, 101498 (2021).
  • [93] P. Cerda-Duran and N. Elias-Rosa, Neutron stars formation and core collapse supernovae, in The Physics and Astrophysics of Neutron Stars, edited by L. Rezzolla, P. Pizzochero, D. I. Jones, N. Rea, and I. Vidaña (Springer International Publishing, Cham, 2018) pp. 1– 56.
  • [94] A. Burrows, D. Vartanyan, and T. Wang, The Astrophysical Journal 957, 68 (2023).
  • [95] W. Zhang, S. E. Woosley, and A. Heger, The Astrophysical Journal 679, 639 (2008).
  • [96] A. P. Igoshev, A. Frantsuzova, K. N. Gourgouliatos, S. Tsichli, L. Konstantinou, and S. B. Popov, Monthly Notices of the Royal Astronomical Society 514, 4606 (2022).
  • [97] F. Özel and P. Freire, Annual Review of Astronomy and Astrophysics 54, 401 (2016).
  • [98] D. Thornton, B. Stappers, M. Bailes, B. Barsdell, S. Bates, N. D. R. Bhat, M. Burgay, S. Burke-Spolaor, D. J. Champion, P. Coster, N. D’Amico, A. Jameson, S. Johnston, M. Keith, M. Kramer, L. Levin, S. Milia, C. Ng, A. Possenti, and W. van Straten, Science 341, 53 (2013), https://www.science.org/doi/pdf/10.1126/science.1236789.
  • [99] S. Yamasaki, T. Goto, C. T. Ling, and T. Hashimoto, Monthly Notices of the Royal Astronomical Society 527, 11158 (2023).
  • [100] D. R. Lorimer, Living Reviews in Relativity 11, 8 (2008).
  • [101] S. J. Swihart, J. Strader, L. Chomiuk, E. Aydi, K. V. Sokolovsky, P. S. Ray, and M. Kerr, The Astrophysical Journal 941, 199 (2022).
  • [102] K. I. I. Koljonen and M. Linares, The Astrophysical Journal 994, 8 (2025).
  • [103] S. M. Adams, C. S. Kochanek, J. F. Beacom, M. R. Vagins, and K. Z. Stanek, The Astrophysical Journal 778, 164 (2013). SUPPLEMENTAL MATERIAL I. MODELING THE SUPRAMASSIVE NS PROGENITOR IN MSTT. With the scalar-field mass mΦ specified, the MSTT parameters (α0, β0) can be constrained by requiring the theory to reproduce observed NS properties. Since the theory must simultaneously support the observed masses and rotation rates of known pulsars, we consider a set of parameters capable of reproducing the observed properties of the black widow pulsar PSR J0952-0607 [44]. This is among the most massive and fastest spinning NS known, with a gravitational mass of 2.35 ± 0.11 M⊙ and a spin frequency of 707 Hz [45]. By reproducing the extreme properties of PSR J0952-0607 for a given EoS and theory parameters, our model will inherently accommodate the entire, less extreme pulsar population. The spin frequency is measured independently of the gravitational theory for PSR J0952-0607. The mass measurement of the NS is derived from the motion and heating of its subsolar mass companion star, obtained through purely Newtonian methods in which the gravity theory enters only through the gravitational constant G [44]. As