Potential of Core-Collapse Supernova Neutrino Detection at JUNO

JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

Detection of the Diffuse Supernova Neutrino Background with JUNO

As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

Double-beta decay with emission of single free electron

We study a new mode of the neutrinoless and two-neutrino double-beta decays in which one of the electrons is emitted from the atom, while the other is directly produced in one of the available s1/2 or p1/2 subshells of the daughter ion. We calculate the phase-space factors, estimate the half-lives and derive the single-electron spectra for 0+ → 0+ ground-state nuclear transitions of the most relevant double-beta-decay isotopes: 48Ca, 76Ge, 82Se, 100Mo, 136Xe and 150Nd. The relativistic electron wave functions are evaluated at the nuclear radius by means of the multiconfiguration Dirac–Hartree–Fock package Grasp2K. We discuss the prospects for detecting these new modes in the tracking-and-calorimetry experiments NEMO-3 and SuperNEMO

Working for 200 Euro? The Unintended Effects of Traineeship Reform on Youth Labor Market Outcomes

This paper evaluates the effects of an active labor market policy (ALMP) reform, the so-called SOR measure (vocational training for work without commencing employment), on youth labor market outcomes in the newest EU member state—Croatia. In 2012, SOR was redesigned to ease the first labor market entry and promote on-the-job training, enabling a young person without relevant work experience to get a one-year contract and a net monthly remuneration of 210 euro, while after 2014, the measure also became a part of the European Youth Guarantee. Pooling Croatian Labor Force Surveys from 2007 to 2016 and using the difference-in-difference strategy, we estimate the causal intent-to-treat effect of the program reform on labor market outcomes. The main results indicate that the reform has had, at best, neutral effects on employment and unemployment, while there is evidence that a portion of young individuals was propelled into inactivity. Though expected, adverse effect on wages—both at the mean and at higher percentiles of the wage distribution—is driven mostly by wages received by women and university graduates