Abstract Although Cherenkov detectors of high-energy neutrinos in ice and water are often optimized to detect teraelectronvolt–petaelectronvolt neutrinos, they may also be sensitive to transient neutrino sources in the 1–100 GeV energy range. A wide variety of transient sources have been predicted to emit gigaelectronvolt neutrinos. In light of the upcoming IceCube Upgrade, which will extend the IceCube detector’s sensitivity down to a few gigaelectronvolts, as well as improve its angular resolution, we survey a variety of transient-source models and compare their predicted neutrino fluences to detector sensitivities, in particular those of IceCube-DeepCore and the IceCube Upgrade. We consider ranges of neutrino fluence from transients powered by nonrelativistic shocks, such as novae, supernovae, fast blue optical transients, and tidal disruption events. We also consider fast radio bursts and relativistic outflows of high- and low-luminosity gamma-ray bursts. Our study sheds light on the prospects of observing gigaelectronvolt transients with existing and upcoming neutrino facilities. 
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                            Finding Fast Transients in Real Time Using a Novel Light-curve Analysis Algorithm
                        
                    
    
            Abstract The current data acquisition rate of astronomical transient surveys and the promise for significantly higher rates in the next decade necessitate the development of novel approaches to analyze astronomical data sets and promptly detect objects of interest. The Deeper, Wider, Faster (DWF) program is a survey focused on the identification of fast-evolving transients, such as fast radio bursts, gamma-ray bursts, and supernova shock breakouts. It employs multifrequency simultaneous coverage of the same part of the sky over several orders of magnitude. Using the Dark Energy Camera mounted on the 4 m Blanco telescope, DWF captures a 20 s g -band exposure every minute, at a typical seeing of ∼1″ and an air mass of ∼1.5. These optical data are collected simultaneously with observations conducted over the entire electromagnetic spectrum—from radio to γ -rays—as well as cosmic-ray observations. In this paper, we present a novel real-time light-curve analysis algorithm, designed to detect transients in the DWF optical data; this algorithm functions independently from, or in conjunction with, image subtraction. We present a sample of fast transients detected by our algorithm, as well as a false-positive analysis. Our algorithm is customizable and can be tuned to be sensitive to transients evolving over different timescales and flux ranges. 
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                            - Award ID(s):
- 1831682
- PAR ID:
- 10387949
- Date Published:
- Journal Name:
- The Astronomical Journal
- Volume:
- 163
- Issue:
- 2
- ISSN:
- 0004-6256
- Page Range / eLocation ID:
- 95
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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