Both astronomical observations of the interaction of Type II supernova remnants ( SNR ) with dense interstellar clouds as well as cosmochemical studies of the abundances of daughter products of short-lived radioisotopes ( SLRIs ) formed by supernova nucleosynthesis support the hypothesis that the Solar System’s SLRIs may have been derived from a supernova .
This paper continues a series devoted to examining whether such a shock wave could have triggered the dynamical collapse of a dense , presolar cloud core and simultaneously injected sufficient abundances of SLRIs to explain the cosmochemical evidence .
Here we examine the effects of shock waves striking clouds whose spin axes are oriented perpendicular , rather than parallel , to the direction of propagation of the shock front .
The models start with 2.2 M _ { \odot } cloud cores and shock speeds of 20 or 40 km s ^ { -1 } .
Central protostars and protoplanetary disks form in all models , though with disk spin axes aligned somewhat randomly .
The disks derive most of their angular momentum not from the initial cloud rotation , but from the Rayleigh-Taylor fingers that also inject shock wave SLRIs .
Injection efficiencies , f _ { i } , the fraction of the incident shock wave material injected into the collapsing cloud core , are ∼ 0.04 - 0.1 in these models , similar to when the rotation axis is parallel to the shock propagation direction .
Evidently altering the rotation axis orientation has only a minor effect on the outcome , strengthening the case for this scenario as an explanation for the Solar System’s SLRIs .