Abstract: | The IceCube Collaboration has observed a high-energy astrophysical neutrino
flux and recently found evidence for neutrino emission from the blazar TXS
0506+056. However, the source or sources of most of the observed flux remains
uncertain. Through-going muons produced by muon-neutrinos are ideal to search
for point-like neutrino emission from astrophysical sources because their
arrival direction can be resolved with an angular resolution $leq1^circ$.
Here, an unbinned search for steady point-like neutrino sources is performed
based on eight years of IceCube data measured between 2009 and 2017. Compared
to previous searches, this search includes an improved event selection and
reconstruction and it is optimized for point-like neutrino emission with the
same flux-characteristics as the observed astrophysical muon-neutrino flux. The
result is an improvement in flux sensitivity of ~35% assuming an $E^{-2}$
spectrum. The sensitivity on the muon-neutrino flux is at a level of $E^2
mathrm{d} N /mathrm{d} E = 3cdot
10^{-13},mathrm{TeV},mathrm{cm}^{-2},mathrm{s}^{-1}$. No new evidence for
neutrino sources is found in a full sky scan and in an a priori candidate
source list. Furthermore, no significant excesses above background are found
from populations of sub-threshold sources. The implications of the
non-observation for potential source classes are discussed. |