Measurement of the diffuse astrophysical neutrino flux over six seasons using cascade events from the Baikal-GVD expanding telescope

Measurement of the diffuse astrophysical neutrino flux over six seasons using cascade events from the Baikal-GVD expanding telescope
GVD Collaboration, V. A. Allakhverdyan, A. D. Avrorin, A. V. Avrorin, V. M. Aynutdinov, Z. Bev{n}uv{s}ov’a, I. A. Belolaptikov, E. A. Bondarev, I. V. Borina, N. M. Budnev, V. A. Chadymov, A. S. Chepurnov, V. Y. Dik, A. N. Dmitrieva, G. V. Domogatsky, A. A. Doroshenko, R. Dvornick’y, A. N. Dyachok, Zh. -A. M. Dzhilkibaev, E. Eckerov’a, T. V. Elzhov, V. N. Fomin, A. R. Gafarov, K. V. Golubkov, T. I. Gress, K. G. Kebkal, V. K. Kebkal, I. V. Kharuk, S. S. Khokhlov, E. V. Khramov, M. M. Kolbin, S. O. Koligaev, K. V. Konischev, A. V. Korobchenko, A. P. Koshechkin, V. A. Kozhin, M. V. Kruglov, V. F. Kulepov, A. A. Kulikov, Y. E. Lemeshev, M. V. Lisitsin, S. V. Lovtsov, R. R. Mirgazov, D. V. Naumov, A. S. Nikolaev, I. A. Perevalova, A. A. Petrukhin, D. P. Petukhov, E. N. Pliskovsky, M. I. Rozanov, E. V. Ryabov, G. B. Safronov, B. A. Shaybonov, V. Y. Shishkin, E. V. Shirokov, F. v{S}imkovic, A. E. Sirenko, A. V. Skurikhin, A. G. Solovjev, M. N. Sorokovikov, I. v{S}tekl, A. P. Stromakov, O. V. Suvorova, V. A. Tabolenko, V. I. Tretjak, B. B. Ulzutuev, Y. V. Yablokova, D. N. Zaborov, S. I. Zavjalov, D. Y. Zvezdov
arXiv:2507.01893v1 Announce Type: new
Abstract: We present an updated measurement of the diffuse astrophysical neutrino flux using Baikal-GVD cascade data collected between April 2018 to March 2024. In this period, the detector grew from 15% to 55% of its baseline cubic kilometer configuration. The diffuse astrophysical neutrino flux is detected with a statistical significance of 5.1 $sigma$. Assuming a single power law model of the astrophysical neutrino flux with identical contribution from each neutrino flavor, the following best-fit parameter values are found: the spectral index $gamma_{astro}$ = 2.64$^{+0.09}_{-0.11}$ and the flux normalization $phi_{astro}$ = 4.42$^{+2.31}_{-1.29}times10^{-18} text{GeV}^{-1}text{cm}^{-2}text{s}^{-1}text{sr}^{-1}$ per one flavor at 100 TeV. These results are broadly consistent with IceCube measurements.arXiv:2507.01893v1 Announce Type: new
Abstract: We present an updated measurement of the diffuse astrophysical neutrino flux using Baikal-GVD cascade data collected between April 2018 to March 2024. In this period, the detector grew from 15% to 55% of its baseline cubic kilometer configuration. The diffuse astrophysical neutrino flux is detected with a statistical significance of 5.1 $sigma$. Assuming a single power law model of the astrophysical neutrino flux with identical contribution from each neutrino flavor, the following best-fit parameter values are found: the spectral index $gamma_{astro}$ = 2.64$^{+0.09}_{-0.11}$ and the flux normalization $phi_{astro}$ = 4.42$^{+2.31}_{-1.29}times10^{-18} text{GeV}^{-1}text{cm}^{-2}text{s}^{-1}text{sr}^{-1}$ per one flavor at 100 TeV. These results are broadly consistent with IceCube measurements.