Neutrinos above the Earth's Surface

In article “Doppler Effect and neutrino acoustic signatures”, published in the journal “LA MULTIAPP” on February 25, 2022, I was forced to touch on an astrophysical topic when, in the data stream obtained by monitoring the acoustic noise of the earth’s crust with high amplitude resolution (more 240 dB) and in a wide frequency band (from 0.1 Hz to 50 kHz) events began to appear, the forms and frequencies of which are not typical for geophysics and seismology. Similar forms can be seen in works on the detection of acoustic traces of neutrino decay in water and ice. The possibilities of increasing the sensitivity in measurements in a solid medium are discussed. In addition, underwater and underground facilities are being built that use the effect of Cherenkov radiation. All of these methods require complex and very expensive installations on a huge scale. Even acoustic measurements in water and in wells are very laborious and expensive, and most importantly: such measurements are forever tied to a specific place. Therefore, the creation of a light, compact and mobile device for recording acoustic traces of neutrino decay is an urgent task, the solution of which will allow recording traces of neutrino decay not only in water and the earth's crust, but also in air, into space, on planets and satellites

Doppler Effect and Acoustic Trails of Neutrinos

In the monitoring mode, signals averaged over 1 minute were recorded in four one-third octave bands: 30, 160, 500 and 1200 Hz. Sometimes, audio signals were recorded using a computer sound card. These signals had varied and surprising forms, but there was no technical capability to record them in monitoring mode. This opportunity appeared in California in 2015. In the period from 2015 to 2017, in the SAFOD pilot well in California at a depth of 1000 m with coordinates 35.974257 N, -120.552076 W, seismological surveys were carried out for the first time using the innovative MIG-3V geophone with a wide band in the infrasonic and sound frequency ranges and in the amplitude range of more than 240 dB. In August 2016, a similar geophone for the same purpose was installed in the VGS well with coordinates 56.967017 N, 43.720605 E to a depth of 1400 m. Digital data in the automatic monitoring mode was recorded continuously every 0.1 ms. Analysis of the data obtained in the SAFOD well (more than 4 TB) showed that, along with seismic signals, there are acoustic traces in the data, which have never been observed in the wells before. Similar tracks were observed in the VGS well. Acoustic trails similar in shape and frequency are observed in the aquatic environment of lakes and Oceans when searching for acoustic trails from high-energy cosmic particles, in particular, with the help of acoustic neutrino detectors

Drude conductivity of a granular metal

We present a complete derivation of the granular analogue to Drude conductivity using diagrammatic methods. The convergence issues arising when changing the order of momentum and frequency summation are more severe than in the homogeneous case. This is because there are now two momentum sums rather than one, due to the intragrain momentum scrambling in tunnelling events. By careful analytic continuation of the frequency sum, and use of integration by parts, we prove that the system is in the normal (non-superconducting) state, and derive the formula for the granular Drude conductivity expected from Einstein's relation and Fermi's golden rule. We also show that naively performing the momentum sums first gives the correct result, provided that we interpret a divergent frequency sum by analytic continuation using the Hurwitz zeta function.Comment: 18 pages, 5 figure