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

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

Evaluation and development of data assimilation in atmospheric dispersion models for use in nuclear emergencies

published_or_final_versionabstractPhysicsDoctoralDoctor of Philosoph

Paternal Dietary Methionine Supplementation Improves Carcass Traits and Meat Quality of Chicken Progeny

The effects that maternal dietary methionine have on progeny have been reported on broilers. However, the paternal effects are not known, so the current study was conducted to explore the influences of paternal dietary methionine (Met) have on progeny carcass traits, meat quality, and related gene expressions. A total of 192 hens and 24 roosters from Ross parent stock at 36 weeks of age were selected. From week 37 to 46, the roosters were allocated to two groups with three replicates of 4 cocks each, (control, 0.28% Met), and methionine group (MET group, 0.28% Met + 0.1% coated Met). The results revealed that, although the heavier live body weight in progeny at day 49 of control group compared to MET group (p p p 24 h value, shear force (g) and drip loss (%) were observed in MET group (p p 24 h) and yellowness (b*24 h) were increased (p p PRKAG2 and PRDX4 supported the changes in muscle pH, with these up-regulated in thigh and breast muscles of MET group, the PPP1R3A gene supported the changes in pH value being down-regulated (p BCO1 gene expression was consistent with the changes in meat color and was up-regulated (p < 0.01) in thigh muscles of MET group, consistent with the changes in b* color values. Finally, it was concluded that the supplementation of 0.1% Met to rooster diets could improve carcass characteristics and meat quality of progeny

Paternal Dietary Methionine Supplementation Improves Carcass Traits and Meat Quality of Chicken Progeny

The effects that maternal dietary methionine have on progeny have been reported on broilers. However, the paternal effects are not known, so the current study was conducted to explore the influences of paternal dietary methionine (Met) have on progeny carcass traits, meat quality, and related gene expressions. A total of 192 hens and 24 roosters from Ross parent stock at 36 weeks of age were selected. From week 37 to 46, the roosters were allocated to two groups with three replicates of 4 cocks each, (control, 0.28% Met), and methionine group (MET group, 0.28% Met + 0.1% coated Met). The results revealed that, although the heavier live body weight in progeny at day 49 of control group compared to MET group (p &lt; 0.05), the relative eviscerated yield and relative thigh muscle yield were higher in MET group (p &lt; 0.05); but the relative abdominal fat was lower (p &lt; 0.05). In thigh and breast muscles, a positive response of pH24 h value, shear force (g) and drip loss (%) were observed in MET group (p &lt; 0.05). The lightness (L) and redness (a) were increased (p &lt; 0.05) in breast muscles of MET group, while only the redness (a*24 h) and yellowness (b*24 h) were increased (p &lt; 0.05) in thigh muscles of MET group. The gender has a significant (p &lt; 0.05) effect on carcass traits and muscle redness (a*), where these traits improved in males, and no interaction between treatments and gender were observed for these results. The expression levels of PRKAG2 and PRDX4 supported the changes in muscle pH, with these up-regulated in thigh and breast muscles of MET group, the PPP1R3A gene supported the changes in pH value being down-regulated (p &lt; 0.01) in these same muscles. The BCO1 gene expression was consistent with the changes in meat color and was up-regulated (p &lt; 0.01) in thigh muscles of MET group, consistent with the changes in b* color values. Finally, it was concluded that the supplementation of 0.1% Met to rooster diets could improve carcass characteristics and meat quality of progeny

A Critical Role of Inhibition in Temporal Processing Maturation in the Primary Auditory Cortex.

Faithful representation of sound envelopes in primary auditory cortex (A1) is vital for temporal processing and perception of natural sounds. However, the emergence of cortical temporal processing mechanisms during development remains poorly understood. Although cortical inhibition has been proposed to play an important role in this process, direct in-vivo evidence has been lacking. Using loose-patch recordings in rat A1 immediately after hearing onset, we found that stimulus-following ability in fast-spiking neurons was significantly better than in regular-spiking (RS) neurons. In-vivo whole-cell recordings of RS neurons revealed that inhibition in the developing A1 demonstrated much weaker adaptation to repetitive stimuli than in adult A1. Furthermore, inhibitory synaptic inputs were of longer duration than observed in vitro and in adults. Early in development, overlap of the prolonged inhibition evoked by 2 closely following stimuli disrupted the classical temporal sequence between excitation and inhibition, resulting in slower following capacity. During maturation, inhibitory duration gradually shortened accompanied by an improving temporal following ability of RS neurons. Both inhibitory duration and stimulus-following ability demonstrated exposure-based plasticity. These results demonstrate the role of inhibition in setting the pace for experience-dependent maturation of temporal processing in the auditory cortex

Full-band, multi-angle, multi-scale, and temporal dynamic field spectral measurements in China

Abstract Field-measured spectra are critical for remote sensing physical modelling, retrieval of structural, biophysical, and biochemical parameters, and other practical applications. We present a library of field spectra, which includes (1) portable field spectroradiometer measurements of vegetation, soil, and snow in the full-wave band, (2) multi-angle spectra measurements of desert vegetation, chernozems, and snow with consideration of the anisotropic reflectance of land surface, (3) multi-scale spectra measurements of leaf and canopy of different vegetation cover surfaces, and (4) continuous reflectance spectra time-series data revealing vegetation growth dynamics of maize, rice, wheat, rape, grassland, and so on. To the best of our knowledge, this library is unique in simultaneously providing full-band, multi-angle, multi-scale spectral measurements of the main surface elements of China covering a large spatial extent over a 10-year period. Furthermore, the 101 by 101 satellite pixels of Landsat ETM/OLI and MODIS surface reflectance centered around the field site were extracted, providing a vital linkage between ground measurements and satellite observations. The code language used for this work is Matlab 2016a