Searches for and Characterization of Astrophysical Neutrinos using Starting Track Events in IceCube
M. Silva, Rasha Abbasi, M. Ackermann, Jenni Adams, Juanan Aguilar, M. Ahlers, Maryon Ahrens, Cyril Martin Alispach, A. A. Alves, Najia Moureen Binte Amin, Rui An, K. Andeen, Tyler Anderson, G. Anton, C. Argüelles, Yosuke Ashida, Spencer Axani, X. Bai, Aswathi Balagopal, Anastasia Maria Barbano, S. W. Barwick, Benjamin Bastian, Vedant Basu, S. Baur, Ryan Bay, J. J. Beatty, K. H. Becker, J. Becker Tjus, Chiara Bellenghi, S. BenZvi, D. Berley, E. Bernardini, Dominique Besson, G. Binder, D. Bindig, E. Blaufuss, Summer Blot, Matthias Boddenberg, Federico Bontempo, Jürgen Borowka, S. Böser, O. Botner, Jakob Boettcher, Etienne Bourbeau, Federica Bradascio, J. Braun, S. Bron, Jannes Brostean-Kaiser, Sally-Ann Browne, A. Burgman, Ryan T. Burley, Raffaela Busse, Michael Campana, Erin Carnie-Bronca, Chujie Chen, D. Chirkin, K. Choi, Brian Clark, Kenneth Clark, Lew Classen, Alan Coleman, Gabriel Collin, J. M. Conrad, Paul Coppin, Pablo Correa, D. F. Cowen, R. Cross, Christian Dappen, Pranav Dave, C. De Clercq, James DeLaunay, H.-P. Dembinski, Kunal Deoskar, Sam De Ridder, Abhishek Desai, P. Desiati, K. D. de Vries, G. de Wasseige, Meike De With, T. DeYoung, Sukeerthi Dharani, Alejandro Díaz, J. C. Díaz–Vélez, Markus Dittmer, Hrvoje Dujmović, M. Dunkman, M. A. DuVernois, Emily Dvorak, Thomas Ehrhardt, P. Eller, Ralph Engel, Hannah Erpenbeck, John Evans, P. A. Evenson, Kwok Lung Fan, A. R. Fazely, Sebastian Fiedlschuster, Aaron Fienberg, Kirill Filimonov, C. Finley
Abstract
The IceCube Neutrino Observatory is a cubic kilometer-sized detector designed to detect neutrinos of astrophysical origin. However, muons created by cosmic rays interacting in the atmosphere pose a significant background for these astrophysical neutrinos particularly in the southern equatorial sky. Identifying neutrino events that start in the detector allows us to reduce the atmospheric muon component while retaining a high rate of starting neutrino events. The method presented today also rejects atmospheric neutrinos if they are accompanied by muons from the same cosmic ray shower, lowering the 50$\%$ purity threshold for astrophysical-to-atmospheric neutrinos from 100 TeV to ~10 TeV at declinations less than -25°. We use 10$\%$ (burn sample) of 9.5 years IceCube data to demonstrate the status of this dataset. We outline a planned measurement of the diffuse neutrino flux inclusive of theoretical and detector systematic uncertainties. In addition, we discuss searches for neutrino point sources and diffuse galactic plane neutrino emission in the Southern sky and plans to release high astrophysical-purity real-time alerts to the multi-messenger community.