1. Cara Esposito Saint Joseph’s University Dr. Kate Scholberg Duke University

2.  Brief background on neutrinos, supernovae, and the HALO detector  Efficiency and the important information gained from examining the efficiency  Sensitivity for HALO  Summary

3. The Equation above is for the probability of detecting flavor g at L for a two flavor case. Although there are three flavors, the Δ m 2 remains Normal Mass Hierarchy (NMH) has one heavy and two light mass states, while IMH has two heavy and one light mass state

4.  Supernovae happen when a massive star can no longer sustain itself and it explodes  99% of the energy of core collapse supernovae is neutrinos BeforeAfter

5.  SNOLab in Canada  79 tons of lead  128 helium detectors  2 km underground  HALO 2 is currently in the developing phase and will most likely use 1 kiloton of lead Helium Detectors Lead

6.  Visualization of the simulation using Geant4

7. ___

15.  The left panel is for inverted mass hierarchy  The right panel is for normal mass hierarchy

16.  From the energy deposited in the detector we can determine whether it’s a 1N or a 2N event.

17. 1N 2n

18. Tells us how well the detector works

19.  HALO 1’s sensitivity for 5kpc supernovae  Contours in which ninety percent of the number of one- neutron and two- neutron events fall  The different colored curves correspond to different spectral parameters

20.  For 10 kpc supernovae HALO 1 can only constrain extreme models

21.  HALO 2 ‘s discriminatory power will increase with a greater number of counts for 10 kpc supernovae.

22.  Simulated neutron events in the HALO Geant4 simulator  Efficiency for 1N events is approximately 36%  Efficiency for 2N events is approximately 56%  HALO 1 has good sensitivity for 5 kpc supernovae, but can only constrain extreme models for 10 kpc supernovae  HALO 2 the larger the number of counts, the greater the yield for the discriminatory power

23.  K.Scholberg, C.Walter, A.Himmel, Duke University High Energy Physics Neutrino Group  Triangle Universities Nuclear Laboratory's Research Experience for Undergraduates  Halo Collaboration/SNOLab