We use cookies to ensure that we give you the best experience on our website. You can change your cookie settings at any time. Otherwise, we'll assume you're OK to continue.

Durham University

Department of Physics

Staff profile

Publication details for Prof Sir Arnold Wolfendale

Erlykin, AD & Wolfendale, AW (2005). 'Sling effect' in the development of atmospheric cascades induced byprimary cosmic ray nuclei. Journal Of Physics G-nuclear And Particle Physics 31(7): 791-802.
  • Publication type: Journal Article
  • ISSN/ISBN: 0954-3899

Author(s) from Durham


The 'sling effect' appears when a fragment of a projectile nucleus
emitted after its peripheral collision with a target nucleus is caused
to rotate with high spin. The spinning fragment has a deformed shape
and looks like an oblate ellipsoid. Due to the virtual
non-compressibility of nuclear matter, and the polarization of the spin
in the plane transverse to the input momentum of the projectile
nucleus, such an ellipsoid has a reduced mean interaction cross-section
compared with a non-spinning fragment which has a spherical shape.
Purely geometrical arguments dictate that such an ellipsoidal nucleus
should have additional fluctuations of cross-section even at a fixed
impact parameter dependent on the orientation angle between the axis of
the ellipsoid and the vector connecting the centres of the projectile
and target nucleus. The number of 'wounded nucleons' in the projectile
nucleus participating in the interaction correlates strongly with the
interaction cross-section. All these effects lead to a non-exponential
attenuation of fragments and an increased probability for a fragment to
penetrate down to a larger depth in the absorber, than normal. If the
sling effect appears in the interaction of a primary cosmic ray nucleus
with nuclei in the atmosphere, the induced atmospheric cascade will
have a slower attenuation, and thereby can help us to reduce some
important inconsistencies in the interpretation of the existing
experimental data on extensive air showers observed in the lower half
of the atmosphere. The paper gives numerical estimates of the sling