We report the results of a five-year survey of the northern sky to search for point sources of high energy neutrinos .
The search was performed on the data collected with the AMANDA-II neutrino telescope in the years 2000 to 2004 , with a live-time of 1001 days .
The sample of selected events consists of 4282 upward going muon tracks with high reconstruction quality and an energy larger than about 100 GeV .
We found no indication of point sources of neutrinos and set 90 % confidence level flux upper limits for an all-sky search and also for a catalog of 32 selected sources .
For the all-sky search , our average ( over declination and right ascension ) experimentally observed upper limit \mathrm { \Phi ^ { 0 } = \big ( \frac { E } { 1 TeV } \big ) ^ { \gamma } \cdot \frac { d \Phi } { dE } } to a point source flux of muon and tau neutrino ( detected as muons arising from taus ) is \mathrm { \Phi _ { \nu _ { \mu } + \bar { \nu } _ { \mu } } ^ { \mathrm { 0 } } + \Phi _ { \nu _ { \tau } + \bar { % \nu } _ { \tau } } ^ { \mathrm { 0 } } } = 11.1 \cdot 10 ^ { -11 } \mathrm { TeV } ^ { -1 } \mathrm { cm } ^ % { -2 } \mathrm { s } ^ { -1 } , in the energy range between 1.6 TeV and 2.5 PeV for a flavor ratio \mathrm { \Phi _ { \nu _ { \mu } + \bar { \nu } _ { \mu } } ^ { \mathrm { 0 } } / \Phi _ { \nu _ { \tau } + \bar { % \nu } _ { \tau } } ^ { \mathrm { 0 } } } = 1 and assuming a spectral index \gamma =2 .
It should be noticed that this is the first time we set upper limits to the flux of muon and tau neutrinos .
In previous papers we provided muon neutrino upper limits only neglecting the sensitivity to a signal from tau neutrinos , which improves the limits by 10 % to 16 % .
The value of the average upper limit presented in this work corresponds to twice the limit on the muon neutrino flux \mathrm { \Phi _ { \nu _ { \mu } + \bar { \nu } _ { \mu } } ^ { \mathrm { 0 } } } = 5.5 \cdot 10 ^ { -11 } % \mathrm { TeV } ^ { -1 } \mathrm { cm } ^ { -2 } \mathrm { s } ^ { -1 } .
A stacking analysis for preselected active galactic nuclei and a search based on the angular separation of the events were also performed .
We report the most stringent flux upper limits to date , including the results of a detailed assessment of systematic uncertainties .