Fundamental to classical and quantum vortices, superconductors, magnetic flux tubes, liquid crystals, cosmic strings, and DNA is the phenomenon of reconnection of linelike singularities. We visualize reconnection of quantum vortices in superfluid^{4}He, using submicrometer frozen air tracers. Compared with previous work, the fluid was almost at rest, leading to fewer, straighter, and slowermoving vortices. For distances that are large compared with vortex diameter but small compared with those from other nonparticipating vortices and solid boundaries (called here the intermediate asymptotic region), we find a robust 1/2power scaling of the intervortex separation with time and characterize the influence of the intervortex angle on the evolution of the recoiling vortices. The agreement of the experimental data with the analytical and numerical models suggests that the dynamics of reconnection of long straight vortices can be described by selfsimilar solutions of the local induction approximation or Biot–Savart equations. Reconnection dynamics for straight vortices in the intermediate asymptotic region are substantially different from those in a vortex tangle or on distances of the order of the vortex diameter.
more » « less NSFPAR ID:
 10083741
 Publisher / Repository:
 Proceedings of the National Academy of Sciences
 Date Published:
 Journal Name:
 Proceedings of the National Academy of Sciences
 Volume:
 116
 Issue:
 6
 ISSN:
 00278424
 Page Range / eLocation ID:
 p. 19241928
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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