Prospects for detecting generic fast-time features in the neutrino lightcurve of nearby supernovae in neutrino telescopes

Neutrino emission offers a direct probe into the hydrodynamics and energy transport processes within a supernova. Fast-time variations in the neutrino luminosity and mean energy can provide insights into phenomena like turbulence, convection, and shock revival. In this paper, we explore the detection capabilities of large-volume neutrino telescopes such as the IceCube Neutrino Observatory and the planned IceCube-Gen2 detector in identifying generic fast-time features in the neutrino lightcurve. We also investigate the potential enhancement in detection sensitivity using wavelength shifters, which can improve light collection efficiency. By employing a short-time Fourier transform analysis, we quantify the excess power in the frequency spectrum arising from fast-time modulations and compute the detection horizon for a range of generic models. We find that with IceCube we can already see the strongest modulation models (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mo form="prefix">&gt;</a:mo><a:mn>50</a:mn><a:mo>%</a:mo></a:math> amplitude) for progenitors located anywhere in the Milky Way. Sensitivity to weaker modulations (<d:math xmlns:d="http://www.w3.org/1998/Math/MathML" display="inline"><d:mo form="prefix">&gt;</d:mo><d:mn>20</d:mn><d:mo>%</d:mo></d:math> amplitude) is possible in future detectors like IceCube-Gen2, in particular with the use of wavelength shifters. For all detector configurations, the frequency and central time of the fast-time feature at the <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:mrow><g:mn>5</g:mn><g:mi>σ</g:mi></g:mrow></g:math> detection horizon can be measured with a resolution of <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"><i:mrow><i:mn>7.0</i:mn><i:mtext> </i:mtext><i:mtext> </i:mtext><i:mi>Hz</i:mi></i:mrow></i:math> and 17 ms, respectively.