A new force in the dark sector?

作者：Farrar Glennys R^*; Rosen Rachel A

来源：Physical Review Letters, 2007, 98(17): 171302.

DOI：10.1103/PhysRevLett.98.171302

We study the kinematics of dark matter using the massive cluster of galaxies 1E0657-56. The velocity of the "bullet" subcluster (actually, the bow shock velocity) has been measured by x-ray emission from the shock front, and the masses and separation of the main and subclusters have been measured by gravitational lensing. The velocity with gravity alone is calculated in a variety of models of the initial conditions, mass distribution, and accretion history; it is much higher than the velocity of the bow shock, by at least 2.4 sigma. The probability of so large a subcluster velocity in cosmological simulations estimated from the Hayashi-White fit is less than or similar to 10(-7). A long-range force with strength approximate to 0.4-1.2 times that of gravity would provide the corresponding additional acceleration.

• 出版日期2007-4-27