Search Publications
Signatures of minor mergers in Milky Way like disc kinematics: ringing revisited
Gómez, Facundo A.; Minchev, Ivan; O'Shea, Brian W. +2 more
By means of N-body simulations, we study the response of a galactic disc to a minor merger event. We find that non-self-gravitating, spiral-like features are induced in the thick disc. As we have shown in a previous work, this 'ringing' also leaves an imprint in velocity space (the u-v plane) in small spatial regions, such as the solar neighbourho…
An alternative origin for debris rings of planetesimals
Nayakshin, Sergei; Cha, Seung-Hoon
Core accretion (CA), the most widely accepted scenario for planet formation, postulates existence of ∼ km-sized solid bodies, called planetesimals, arranged in a razor-thin disc in the earliest phases of planet formation. These objects coagulate by collisions, eventually building planetary cores. In the tidal downsizing (TD) hypothesis, an alterna…
Axial symmetry breaking of Saturn's thermosphere
Achilleos, N.; Smith, C. G. A.
The source of the various planetary-period signals in Saturn's magnetosphere is at present unknown. We investigate the possibility that the source of these signals is an axially asymmetric wind system in the thermosphere. We describe a feedback mechanism that has the potential to drive such axially asymmetric wind systems. The proposed mechanism r…
Charging of ice grains in Saturn's E ring: theory and observations
Misra, Shikha; Mishra, S. K.; Sodha, M. S.
We have developed a theoretical model for a physical understanding of the charging of ice grains in the plasma of Saturn's E ring. The evaluated results are compared with the available observations and measurements from the Cassini, Hubble Space Telescope, Voyager and Pioneer campaigns. In this formulation, we implement the uniform potential theor…
The ballistic transport instability in Saturn's rings - I. Formalism and linear theory
Ogilvie, Gordon I.; Latter, Henrik N.; Chupeau, Marie
Planetary rings sustain a continual bombardment of hypervelocity meteoroids that erode the surfaces of ring particles on time-scales of 105-107 years. The debris ejected from such impacts re-accretes on to the ring, though often at a slightly different orbital radius from the point of emission. This 'ballistic transport' lead…