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Abstract We compare two-moment-basedenergy-dependentand three variants ofenergy-integratedneutrino transport general-relativistic magnetohydrodynamics simulations of a hypermassive neutron star. To study the impacts due to the choice of the neutrino transport schemes, we perform simulations with the same setups and input neutrino microphysics. We show that the main differences between energy-dependent and energy-integrated neutrino transport are found in the disk and ejecta properties, as well as in the neutrino signals. The properties of the disk surrounding the neutron star and the ejecta in energy-dependent transport are very different from the ones obtained using energy-integrated schemes. Specifically, in the energy-dependent case, the disk is more neutron-rich at early times and becomes geometrically thicker at later times. In addition, the ejecta is more massive and, on average, more neutron-rich in the energy-dependent simulations. Moreover, the average neutrino energies and luminosities are about 30% higher. Energy-dependent neutrino transport is necessary if one wants to better model the neutrino signals and matter outflows from neutron star merger remnants via numerical simulations.
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Unidirectional coherent energy transport via conjugated oligo(p-phenylene) chains
We used relaxation-assisted two-dimensional spectroscopy (RA 2DIR) to interrogate the energy transport within oligo(p-phenylene) chains and discovered a way to funnel high-frequency vibrational quanta rapidly (8.6 km/s) and unidirectionally over large distances. The study opens avenues for developing materials with controllable energy transport properties, and devices photonic or electrical properties.
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- Award ID(s):
- 1900568
- PAR ID:
- 10249910
- Editor(s):
- Kevin Kubarych, Jennifer Ogilvie
- Date Published:
- Journal Name:
- Time Resolved Vibrational Spectroscopy
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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