Astrophysical neutrino flux measurement with 11 years of IceCube cascade data*

The IceCube Neutrino Observatory at the geographical South Pole in Antarctica has discovered a diffuse flux of neutrino signals. Since its discovery, astrophysical neutrino flux has been measured in various detection channels and analyses over a wide 10TeV-10PeV energy range. The most precise measurement and characterization of this flux so far was performed with 6 years (2010-2015) of neutrino induced cascades data, with astrophysical neutrino interactions being dominated by electron and tau neutrino flavors. The - unexpectedly large - flux is consistent with the single unbroken energy power-law function with a soft spectral index of  γ = 2.53 ± 0.07 . IceCube continues collecting more data. Recently the collaboration re-processed historical data, the so-called data "pass2”,  to update and unify across years different analyses data stream filters and calibration. The knowledge of ice (detector medium) continues being improved, resulting in a reduction of the dominant systematic uncertainties in diffuse neutrino analyses.

    In this talk we will present sensitivities and preliminary results of the astrophysical neutrino induced cascade flux measurement with 11 years of data (2010-2020), improved Monte Carlo simulations and cascade reconstruction method (mainly due to improved ice modeling) and other analysis aspects. The new analysis will allow searches for flux features beyond single power law, and tests of astrophysical models.