<<<<<<<<<<<<<< CRC News 2019年 8月 8日 >>>>>>>>>>>>>> CRC会員 各位 　　　　　　　　　　　　　　 　　　 CRC事務局 *************＜Diffuse Workshop on Global Fitの案内＞************* CRC会員の皆様 主催者からの依頼で下記研究会の案内を転送します。 宇宙線研　さこ Diffuse Workshop on Global Fit Earthquake Research Institute, University of Tokyo 14th September 2019 https://events.icecube.wisc.edu/event/115/ The IceCube Neutrino Observatory, located at the South Pole, is the largest neutrino detector in the world with an instrumentation volume of one cubic kilometer. The detector is sensitive to neutrinos from GeV to EeV. In 2013, IceCube announced the detection of a diffuse flux of astrophysical and since confirmed by independent channels such as northern-sky muon neutrino searches and full-sky electron/tau neutrino searches. However, the different analyses target at different specific event classes such as if the interaction vertices are inside the instrumented volume. Results of the best-fit spectrum index assuming a single power-law varies from 2.19 to 2.89 although still consistent within 2 sigma uncertainty. As more data are collected year by year, the statistical errors are decreasing and it becomes more and more important to understand systematics from atmospheric neutrino modeling, earth core uncertainty, hadronic interaction model systematics errors. To be able to understand the reasons behind different results from different event streams, the next step is to combine all event samples from individual searches to cover all detection channels, i.e., a ‘global-fit’. Thus we are organising a workshop on the 14th September at the Earthquake Research Institute, University of Tokyo. If you wish to participate, please register from the following web page: https://forms.gle/rMv6J7ApbFa99Vtz7 The goal of the workshop: * Build a bridge between model builders (Honda-model, MCEq) with IceCube analysers * Explore a unified systematic treatment including hadronic interaction models, earth core and atmospheric neutrino flux * Form small working groups and set benchmarks towards to a diffuse global-fit * Hands-on implementation of new simulations including new ice model treatments The target science goals for diffuse global-fit: * Is there a break in the diffuse spectrum? Precise flux measurements from TeV to 10PeV. * How can neutrino flavours be used for source model tests? * Are IceCube neutrinos from the same source as UHECRs? * When do we expect to see charm component from IceCube data? Organisation and hosts Science committee: Claudio Kopper(MSU), Lu Lu (Chiba University), Nathen Whitehorn (UCLA) LOC: Akimichi Taketa (ERI) ***************************************************************************