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Things that go bump in the sea T. Sloan (Lancaster University). Neutrino interactions (>10 20 eV) Axions (sadly Cotton-Mouton term) Primordial black holes Any other unexpected phenomenon. Expected pulse shapes. Backgrounds give a train of osillations. - PowerPoint PPT Presentation
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Things that go bump in the sea
T. Sloan (Lancaster University)
• Neutrino interactions (>1020 eV)
• Axions (sadly Cotton-Mouton term)
• Primordial black holes
• Any other unexpected phenomenon.
Expected pulse shapes
Backgrounds give a train of osillations.
Limits from array using 4 fold coincidence of hydrophones (from Simon Bevan UCL Thesis)
Increase sensitivity - give up coincidence requirement
• Increases the solid angle coverage since showers detectable outside the plane of the array.
• More noise – ask for bigger pulses
Raw spectrum of peak amplitudes
APPLY CUTS
Final spectrum for 2 weeks of data.
Analyse all 245 days of data selecting triggers with peak pressureabove 0.4 Pa.
Examine all data (245 days)
• 81 events survive with peak pressure above 0.4 Pa.
• Each scanned visually to look for bipolar pulses.
• Most of them are multiple oscillations.
Conclusions
• 2 events (inverted probably background).
• No neutrinos (limit 5 orders of magnitude above W-B). Sensible limits need very large targets e.g. moon or polar ice cap (ANITA).
• No axions
• No primordial blackholes.
• No other unexpected phenomena.
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