Nisia mantovani biography
•
Neutron stars harbour matter under extreme conditions, providing a unique testing ground for fundamental interactions.
Dark matter can be captured by neutron stars via scattering, where kinetic energy is transferred to the star.
This can have a number of observational consequences, such as theheating of old neutron stars to infra-red temperatures.
Previous treatments of the capture process have employed various approximation or simplifications.
We present here an improved treatment of dark matter capture, valid for a wide dark matter mass range, that correctly incorporates all relevant physical effects.
These include gravitational focusing, a fully relativistic scattering treatment, Pauli blocking, neutron star opacity and multi-scattering effects.
We provide general expressions that enable the exact capture rate to be calculated numerically, and derive simplified expressions that are valid for particular interaction types or mass regimes and that greatly increase the computational efficiency.
Our formalism is applicable to the scattering of dark matter from any neutron star constituents, or to the capture of dark matter in other compact objects.
We apply these results to scattering of dark matter from neutrons, protons, leptonic targets, as well as exotic Baryo
•
Artigo bioterra v16_n2_05
•
Introduction
1 Mark B. Adams, ed., The Wellborn Science: Eugenics in Germany, France, Brazil and Russia (New York: Oxford University Press, 1990), 5.
2 Samuel J. Holmes, A Bibliography of Eugenics (Berkeley: University of California Press, 1924).
3 Frank Dikötter, “Race Culture: Recent perspectives on the history of eugenics,” The American Historical Review 103, no. 2 (April 1998): 467. See also Marius Turda, “New Perspectives on Race and Eugenics,” Historical Journal 51, no. 4 (2008): 1115–24.
4 Publications on eugenics in Great Britain and United States are too numerous to list here exhaustively. See, in particular, Lindsay Andrew Farrall, The Origins and Growth of the English Eugenics Movement 1865–1925 (New York: Garland Pub., 1965); Daniel J. Kevles, In the Name of Eugenics. Genetics and the Uses of Human Heredity, rev. ed. (Cambridge, MA: Harvard University Press, 1995); Richard A. Soloway, Demography and Degeneration. Eugenics and the Declining Birthrate in Twentieth Century Britain (Chapel Hill: North Carolina University Press, 1990); Pauline M. H. Mazumdar, Eugenics, human genetics and human failings: the Eugenics Society, its Source and its Critics in Britain (London–New York: Routledge, 1992); Garland E. Allen, “The Misuse of Biological Hierar