arXiv subjects

Bedrich Roskovec

Publications and source records attributed to Bedrich Roskovec.

4 recordsLinked to original sources

arXiv2018

Neutrino Physics with Reactors

Rector neutrinos have been a tool to investigate neutrino properties for more than 60 years. The reactor neutrino flux was measured throughout 80s-90s. In the 2000s, reactor neutrino oscillations at large baselines were observed by the KamLAND experiment and later in 2012 at short baselines by the Daya Bay, Double Chooz and RENO experiments. Reactor neutrino experiments have significantly contributed to our current knowledge of oscillation parameters. The detector technology has been majorly improved over decades and we have entered era of precise measurements. The recent absolute measurement reactor neutrino flux and spectral shape revealed deviations from the prediction model, known as reactor antineutrino flux and spectrum shape anomalies. In this article, we review the latest development in short baseline reactor experiments and we discuss observed anomalies.

hep-ex↗

arXiv2018

Testing a proposed "second continent" beneath eastern China using geoneutrino measurements

Models that envisage successful subduction channel transport of upper crustal materials below 300 km depth, past a critical phase transition in buoyant crustal lithologies, are capable of accumulating and assembling these materials into so-called "second continents" that are gravitationally stabilized at the base of the Transition Zone, at some 600 to 700 km depth. Global scale, Pacific-type subduction (ocean-ocean and ocean-continent convergence), which lead to super continent assembly, were hypothesized to produce second continents that scale to about the size of Australia, with continental upper crustal concentration levels of radiogenic power. Seismological techniques are incapable of imaging these second continents because of their negligible difference in seismic wave velocities with the surrounding mantle. We can image the geoneutrino flux linked to the radioactive decays in these second continents with land and/or ocean-based detectors. We present predictions of the geoneutrino flux of second continents, assuming different scaled models and we discuss the potential of current and future neutrino experiments to discover or constrain second continents. The power emissions from second continents were proposed to be drivers of super continental cycles. Thus, testing models for the existence of second continents will place constraints on mantle and plate dynamics when using land and ocean-based geoneutrino detectors deployed at strategic locations.

physics.geo-ph↗

arXiv2018

Reactor Neutrino Spectrum and Flux Measurement

Reactor neutrinos play a substantial role in the study of the fundamental properties of neutrinos. With current and upcoming precision experiments, it is essential more than ever to understand the reactor neutrino flux and spectrum. However, two discrepancies between prediction and measurement are observed. On the one hand, there is a $\sim6\%$ total measured flux deficit, known as the reactor antineutrino anomaly, consistently seen by several experiments at short baselines. On the other hand, there is an observed excess over prediction for $\barν_e$ energies between 5-7 MeV. We discuss current status of the experimental measurements and provide an outlook.

physics.ins-det↗

arXiv2011

Non-standard antineutrino interactions at Daya Bay

We study the prospects of pinning down the effects of non-standard antineutrino interactions in the source and in the detector at the Daya Bay neutrino facility. It is well known that if the non-standard interactions in the detection process are of the same type as those in the production, their net effect can be subsumed into a mere shift in the measured value of the leptonic mixing angle theta_13. Relaxing this assumption, the ratio of the antineutrino spectra measured by the Daya Bay far and near detectors is distorted in a characteristic way, and good fits based on the standard oscillation hypothesis are no longer viable. We show that, under certain conditions, three years of Daya Bay running can be sufficient to provide a clear hint of non-standard neutrino physics.

hep-ph↗