All Title Author
Keywords Abstract


The Dark Side of Neutron Stars

DOI: 10.1155/2013/856196

Full-Text   Cite this paper   Add to My Lib

Abstract:

We review severe constraints on asymmetric bosonic dark matter based on observations of old neutron stars. Under certain conditions, dark matter particles in the form of asymmetric bosonic WIMPs can be effectively trapped onto nearby neutron stars, where they can rapidly thermalize and concentrate in the core of the star. If some conditions are met, the WIMP population can collapse gravitationally and form a black hole that can eventually destroy the star. Based on the existence of old nearby neutron stars, we can exclude certain classes of dark matter candidates. 1. Introduction Compact stars such as neutron stars and white dwarfs can lead in general to two types of constraints regarding dark matter candidates. The first one has to do with annihilating dark matter that changes the thermal evolution of the star. Annihilation of Weakly Interacting Massive Particles (WIMPs) that are trapped inside compact stars can lead to the production of significant amount of heat that can change the temperature of old stars [1–4]. Such a phenomenon can be in principle contrasted to observations. The second type of constraints is related to asymmetric dark matter [5–12]. Asymmetric dark matter is an attractive alternative to thermally produced dark matter especially due to the intriguing possibility of relating its asymmetry to the baryonic one. For recent reviews see [13, 14]. Due to the asymmetry, WIMP annihilation is not significant in this case. If a certain amount of WIMPs is trapped inside the star, the WIMPs can quite rapidly thermalize and concentrate within a tiny radius in the core of the star. If the WIMP population grows significantly, WIMPs might become self-gravitating and they might collapse forming a mini black hole. Under certain conditions, the black hole might consume the rest of the star, thus leading to the ultimate destruction of the star. However, very old (older than a few billion years) nearby neutron stars have been well observed and studied. The simple presence of such verified old stars leads to the conclusion that no black hole has consumed the star and as we will argue, this can lead to very severe constraints on the properties of certain types of asymmetric dark matter. We should also mention that additional constraints on asymmetric dark matter can be imposed on different ways (e.g., from asteroseismology [15–17], from effects on the transport properties of the neutron stars [18], and/or from hybrid dark matter rich compact stars [19, 20]). One can easily figure out that fermionic WIMPs, due to the fact that they have to overcome Fermi

References

[1]  C. Kouvaris, “WIMP annihilation and cooling of neutron stars,” Physical Review D, vol. 77, no. 2, Article ID 023006, 9 pages, 2008.
[2]  G. Bertone and M. Fairbairn, “Compact stars as dark matter probes,” Physical Review D, vol. 77, no. 4, Article ID 043515, 9 pages, 2008.
[3]  C. Kouvaris and P. Tinyakov, “Can neutron stars constrain dark matter?” Physical Review D, vol. 82, no. 6, Article ID 063531, 2010.
[4]  A. de Lavallaz and M. Fairbairn, “Neutron stars as dark matter probes,” Physical Review D, vol. 81, no. 12, Article ID 123521, 10 pages, 2010.
[5]  I. Goldman and S. Nussinov, “Weakly interacting massive particles and neutron stars,” Physical Review D, vol. 40, no. 10, pp. 3221–3230, 1989.
[6]  C. Kouvaris and P. Tinyakov, “Excluding light asymmetric bosonic dark matter,” Physical Review Letters, vol. 107, no. 9, Article ID 091301, 4 pages, 2011.
[7]  S. D. McDermott, H. B. Yu, and K. M. Zurek, “Constraints on scalar asymmetric dark matter from black hole formation in neutron stars,” Physical Review D, vol. 85, no. 2, Article ID 023519, 12 pages, 2012.
[8]  C. Kouvaris, “Limits on self-interacting dark matter from neutron stars,” Physical Review Letters, vol. 108, no. 19, Article ID 191301, 5 pages, 2012.
[9]  T. Guver, A. E. Erkoca, M. H. Reno, and I. Sarcevic, “On the capture of dark matter by neutron stars,” http://arxiv.org/abs/1201.2400.
[10]  Y. Z. Fan, R. Z. Yang, and J. Chang, “Constraining asymmetric bosonic non-interacting dark matter with neutron stars,” http://arxiv.org/abs/1204.2564.
[11]  N. F. Bell, A. Melatos, and K. Petraki, “Realistic neutron star constraints on bosonic asymmetric dark matter,” Physical Review D, vol. 87, no. 12, Article ID 123507, 15 pages, 2013.
[12]  A. O. Jamison, “Effects of gravitational confinement on bosonic asymmetric dark matter in stars,” Physical Review D, vol. 88, no. 3, Article ID 035004, 2 pages, 2013.
[13]  K. Petraki and R. R. Volkas, “Review of asymmetric dark matter,” International Journal of Modern Physics A, vol. 28, no. 19, Article ID 1330028, 66 pages, 2013.
[14]  K. M. Zurek, “Asymmetric dark matter: theories, signatures, and constraints,” http://arxiv.org/abs/1308.0338.
[15]  I. Lopes and J. Silk, “Solar constraints on asymmetric dark matter,” The Astrophysical Journal, vol. 757, no. 2, article 130, 9 pages, 2012.
[16]  J. Casanellas and I. Lopes, “First asteroseismic limits on the nature of dark matter,” The Astrophysical Journal, vol. 765, no. 1, article L21, 5 pages, 2013.
[17]  J. Casanellas and I. d. Lopes, “Constraints on asymmetric dark matter from asteroseismology,” http://arxiv.org/abs/1307.6519.
[18]  C. J. Horowitz, “Dark matter transport properties and rapidly rotating neutron stars,” http://arxiv.org/abs/1205.3541.
[19]  S. C. Leung, M. C. Chu, L. M. Lin, and K. W. Wong, “Dark-matter admixed white dwarfs,” Physical Review D, vol. 87, no. 12, Article ID 123506, 8 pages, 2013.
[20]  I. Goldman, R. N. Mohapatra, S. Nussinov, D. Rosenbaum, and V. Teplitz, “Possible implications of asymmetric fermionic dark matter for neutron stars,” Physics Letters B, vol. 725, no. 4-5, pp. 200–207, 2013.
[21]  E. W. Mielke and F. E. Schunck, “Boson stars: alternatives to primordial black holes?” Nuclear Physics B, vol. 564, no. 1-2, pp. 185–203, 2000.
[22]  C. Kouvaris and P. Tinyakov, “(Not)-constraining heavy asymmetric bosonic dark matter,” Physical Review D, vol. 87, no. 12, Article ID 123537, 5 pages, 2013.
[23]  H. T. C. Stoof, “Nucleation of Bose-Einstein condensation,” Physical Review A, vol. 45, no. 12, pp. 8398–8406, 1992.
[24]  B. Ya. Zeldovich and I. D. Novikov, Relativistic Astrophysics, vol. 1, The University of Chicago Press, Chicago, Ill, USA, 1972.

Full-Text

comments powered by Disqus