Measurement of the strange particle production in proton-nucleus collisions HERA-B is a fixed target experiment at the 920 GeV HERA proton beam at DESY. Thin wires of different materials are inserted into the proton beam halo and give rise to deep-inelastic proton-nucleus collisions. A di-lepton trigger selects events containing $J/\psi$ decays. The HERA-B detector was completed in the beginning of the year 2000. The running time until September 2000 when the HERA upgrade program began was used to commission the detector and first level trigger. During the commissioning several million minimum bias triggers as well as 16 million di-lepton triggers, both in the electron and in the muon channel, have been recorded. The cross-sections for $\mathrm{K^0_S}$, Lambda and anti-Lambda particle production in proton induced reactions on C, Al, Ti and W targets at $\sqrt{s}=41.6$ GeV have been measured. The cross-section per nucleon, the A dependence of the cross-section, and the transverse momentum differential cross-sections are discussed and compared with extrapolations from data at lower energies. Measurement of the $J/\psi$ production in proton-nucleus collisions} HERA-B is a fixed target experiment at the 920 GeV HERA proton beam at DESY. Thin wires of different materials are inserted into the proton beam halo and give rise to deep-inelastic proton-nucleus collisions. A di-lepton trigger selects events containing $J/\psi$ decays. The HERA-B detector was completed in the beginning of the year 2000. The running time until September 2000, when the HERA upgrade program began, was used to commission the detector and first level trigger. During the commissioning few million minimum bias triggers as well as several million di-lepton triggers, both in the electron and in the muon channel, have been recorded. The shapes of the differential cross sections for inclusive $J/\psi$ production at $\sqrt{s}=41.6$~GeV are measured in the range of $-0.275$ and $c$ where $d\sigma/dx_F \sim (1-|x_F|)^c$. The parameters $<\! pt\! >$ and $c$ are reported and compared to other measurements and theoretical predictions. Measurement of the $\chi_c$ production in proton-nucleus collisions HERA-B is a fixed target experiment at the 920 GeV HERA proton beam at DESY. Thin wires of different materials are inserted into the proton beam halo and give rise to deep-inelastic proton-nucleus collisions. A di-lepton trigger selects events containing $J/\psi$ decays. The HERA-B detector was completed in the beginning of the year 2000. The running time until September 2000 when the HERA upgrade program began was used to commission the detector and first level trigger. During the commissioning several million minimum bias triggers as well as 16 million di-lepton triggers, both in the electron and in the muon channel, have been recorded. The $\chi_{c1}$ and $\chi_{c2}$ are resconstructed via their radiative decays $\chi_{c}\rightarrow J/\psi \gamma$ with subsequent leptonic decay of the $J/\psi$ . In this analysis both leptonic decay channels of the $J/\psi$ are used. With a photon detection efficiency of around 30\% a total of about 380 $\chi_c$ events are reconstructed. Using these events the fraction $R_{\chi_c}$ of $J/\psi$ events produced by radiative decays of the $\chi_{c}$ is determined. The measurement is done separatley for proton-carbon and proton-titanium interaction. The result is compared to other measurements and theoretical predictions. Measurement of the $b \bar b$ production cross section in proton-nucleus collisions HERA-B is a fixed target experiment at the 920 GeV HERA proton beam at DESY. Thin wires of different materials are inserted into the proton beam halo and give rise to deep-inelastic proton-nucleus collisions. A di-lepton trigger selects events containing $J/\psi$ decays. The HERA-B detector was completed in the beginning of the year 2000. The running time until September 2000 when the HERA upgrade program began was used to commission the detector and first level trigger. During the commissioning several million minimum bias triggers as well as di-lepton triggers, both in the electron and in the muon channel, have been recorded. The measurement of the $b \bar b$ production in proton-nucleus interactions uses inclusive $B \rightarrow J/\psi + X$ decays. The B event selection consists first of a $J/\psi$ decay search followed by a cut on the separation between $J/\psi$ decay vertex and the primary vertex of the proton-nucleon interaction. The analysis exploits the excellent resolution of the HERA-B silicon vertex detector. To minimize systematic errors related to the detector and trigger efficiencies and to remove the dependence on the luminosity determination, the $b \bar b$ production is measured relative to the prompt $J/\psi$ production cross section. The number of reconstructed $B \rightarrow J/\psi + X$ candidates in the year 2000 data sample is small ($O(10)$) reflecting the low efficiency of the not-fully commissioned detector and trigger and the small data taking time devoted to physics but nevertheless affords a cross section estimate comparable in precision to the existing measurements at similar beam energies.