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

The Measurement of xi'/xi at Fermilab KTeV-E832

The status of the analysis effort for the 25% data sample taken during the Fermilab '96-'97 fixed target run for {epsilon}'/{epsilon} measurement from KTeV is presented here. Detector performance, data statistics, background subtractions, data and monte-carlo comparison for acceptance corrections, as well as the preliminary results on K{sub L}{yields}{pi}{sup 0}{gamma}{gamma} are described in more detail. Prospects for KTeV 99, in the up coming 6 months '99 fixed target run, are also discussed here

Observation of direct-CP violation

Using a subset of data collected in the 1996-97 fixed target run at Fermilab, the authors report the first preliminary measurement on the direct-CP violation from the KTeV experiment. The result is, e{prime}/e = (28.0-4.1) x 10{sup {minus}4}, nearly 7 standard deviations above zero obtained by a blind analysis. This establishes the long-sought direct-CP violation effect in the two-pion system of neutral kaon decays. The experimental technique, data analysis and systematic checks for this measurement are discussed and the comparison with other measurements is also presented

{epsilon}{prime}/{epsilon} and rare KL decays from KTeV Experiment

The authors update the current status for the measurement of the direct-CP violation parameters {epsilon}{prime}/{epsilon} in the KTeV experiment at Fermilab. Substantial statistics have been accumulated during the 1996-7 run and 1999 run for both {epsilon}{prime}/{epsilon} and rare K{sub L} decay searches. The first KTeV result on {epsilon}{prime}/{epsilon} published last year was Re({epsilon}{prime}/{epsilon}) = (28.0 {+-} 4.1) x 10{sup {minus}4} based on the 23% data from 1996-7 run. Combining with the previous E731, NA31 and the recent preliminary NA48 results, the grand average is Re({epsilon}{prime}/{epsilon}) = (19.3 {+-} 3.6) x 10{sup {minus}4} (with S = 1:49), more than 5{sigma} above zero. More data from both KTeV and NA48 after completing the analysis will further improve the precision of this measurement in the near future and hopefully further improve the agreement. New results on the branching ratio and form factor measurements of K{sub L} {r_arrow} {mu}{sup +} {mu}{sup {minus}} {gamma} using 1997 data are also presented. We find that BR(K{sub L} {r_arrow} {mu}{sup +} {mu}{sup {minus}} {gamma}) = (3.66 {+-} 0.04{sub stat} {+-} 0.07{sub syst}) x 10{sup {minus}7}. The form factor parameter {alpha}{sub K}* is measured to be {alpha}{sub K}* = {minus}0.157{sub {minus}0.027}{sup +0.025}. We make the first measurement of the parameter {alpha} from the D'Ambrosio, Isidori, and Portoles form factor, finding {alpha} = {minus}1.53 {+-} 0.09. This measurement of {alpha} limits the CKM parameter {rho} > {minus}0.2

Observation of direct-CP violation - {epsilon}{prime}{epsilon} from KTeV

The authors report the first KTeV measurement for the search of direct-CP violation by using 23% of the data sample collected in the 1996-97 fixed target run at Fermilab. The result is, Re({epsilon}{prime}/{epsilon}) = (28.0 {+-} 4.1) x 10{sup -4}, nearly 7{delta} above zero obtained by a blind analysis. This firmly establishes the long-sought direct-CP violation effect in the two-pion system ({pi}{sup +}{pi}{sup -} versus {pi}{sup 0}{pi}{sup 0}) of neutral kaon decays

Re({epsilon}{prime}/{epsilon})Result from KTeV - An observation of direct-CP violation

Using a subset of data collected in the 1996-97 fixed target run at Fermilab, the authors report the first preliminary measurement on the direct-CP violation from the KTeV experiment. The result is, e{prime}/e = (28.0-4.1) x 10{sup {minus}4}, nearly 7 standard deviations above zero obtained by a blind analysis. This establishes the long-sought direct-CP violation effect in the two-pion system of neutral kaon decays. The experimental technique, data analysis and systematic checks for this measurement are discussed and the comparison with other measurements is also presented