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Steven Neil Shore

Publications and source records attributed to Steven Neil Shore.

3 recordsLinked to original sources

Multiwavelength spectroscopic study of shock driven phenomena in explosive outbursts in symbiotic-like recurrent novae with emphasis on RS Ophiuchi

To detail the development of RS Ophiuchi and the other Galactic Symbiotic-like Recurrent Novae throughout their outburst and quiescence, with a particular emphasis on the propagation of the shock wave during the outburst of the binaries. The spectral analysis has been performed using archival data according to the features of the individual datasets. Swift grism spectra were reduced and extracted using a combination of the pre-existing UVOTPY Python routine and newly written pipelines in Matlab. Other datasets were directly available in reduced form, already corrected for instrumental or background contamination, calibrated in wavelength and flux or intensity. The work on these was done through pipelines suited for reading the data and elaborating them to extract quantities of interest for the analysis. We find striking similarities in different outbursts of the same object and for different novae. For example, RS Oph 2021 was almost identical to the 2006 outburst, despite having occurred at a different orbital phase with the observations made from a different line of sight through the red giant wind. Despite the intrinsically different properties of the binaries, striking similarities are found for different systems of the same class, for instance, that the trend of the electron density over time during outburst appears to follow a general temporal development.

astro-ph.SR

A semiempirical approach to low-energy cosmic ray propagation in the diffuse interstellar medium

We investigate the ionization of the diffuse interstellar medium by cosmic rays by modeling their propagation along the wandering magnetic fields using a Monte Carlo method. We study how low-energy cosmic rays propagate in turbulent, translucent molecular clouds, and how they regulate the ionization and both lose and gain energy from the medium. As a test case, we use high spatial resolution (0.03 pc) CO maps of a well-studied high latitude translucent cloud, MBM 3, to model turbulence. The propagation problem is solved with a modified Monte Carlo procedure that includes trapping, energization, and ionization losses. In a homogeneous medium, trapping and re-energization do not produce a significant effect. In a nonuniform medium, particles can be trapped for a long time inside the cloud. This modifies the cosmic ray distribution due to stochastic acceleration at the highest energies (about 100 MeV). At lower energies, the re-energization is too weak to produce an appreciable effect. The change in the energy distribution does not significantly affect the ionization losses, so ionization changes are due to trapping effects.

astro-ph.HE