All Figures

	Figure 1: Event rate of simulated -rays as a function of -ray energy for two different sets of selection cuts. The dark grey histogram corresponds to the standard and the light grey histogram to the low energy cuts. The vertical arrows roughly represent the corresponding threshold energy.
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In the text

	Figure 2: Differential energy spectrum of unpulsed VHE -rays from the Crab Nebula obtained with the different sets of selection cuts. The open points correspond to the results of the standard and the full points to the low energy cut analysis (but with  TeV as for the standard cuts). The solid line represents the spectrum parametrisation taken from Aharonian et al. (2006c).
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In the text

Figure 3: Upper plot: distribution of event phases for the Vela pulsar (PSR B0833-45). The points represent the events in the on-region at the pulsar position and the histogram the normalised off-region events. The solid and dashed lines represent the  fits to a constant for the on- and off-events, respectively. For both regions the probabilities for being consistent with a uniform distribution according to the statistical tests on pulsations (see text) are listed along with the pulsed fraction limit as introduced in Sect. 4.3. Lower plot: phase distribution for -rays with energies between 2 and 10 GeV as measured by EGRET (Fierro et al. 1998). The dotted vertical lines denote the edges of the on-pulse regions.

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In the text

	Figure 4: Distribution of event phases for PSR J1420-6048 using the low energy cut analysis for on- and off-regions (see also Fig. 3). Note that there is significant unpulsed emission at the pulsar position resulting in a difference between the mean number of events for the on and off-regions shown by the solid and dashed lines respectively.
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In the text

Figure 5: Ensemble distributions of the H-test statistic for the selected pulsars of Table 6 and their corresponding background control samples. The results for the pulsar direction are shown as open and closed circles for the low energy and standard cut analysis, respectively. The distributions for the off-regions are displayed as grey filled and outlined histograms, respectively. The solid curve shows the expected distribution if no pulsed signals are present.

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In the text

Figure 6: HESS energy flux limits (99% c.l.) for pulsed emission of the Crab pulsar. The full circles and full squares correspond to the on-off-pulse and pulsed fraction limit determination methods, respectively. Below energies of 0.5 TeV the results were obtained with the low energy selection cuts, otherwise the standard cuts were used. Note that the threshold energy of the HESS data lies at 310 GeV due to the observation at high zenith angles imposed by the limited accessibility of the northern sky. The crosses, open squares, and open diamonds denote limits from CELESTE (99% c.l., de Naurois et al. 2002), Whipple (99.9% c.l., Lessard et al. 2000), and HEGRA (99.865% c.l., Aharonian et al. 2004a), respectively. The open triangles show the EGRET phase-averaged spectrum (Fierro et al. 1998). The indicated polar cap curve was generated according to Rudak & Dyks (1999) and the outer gap model curve taken from Hirotani & Shibata (2001a).

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In the text

Figure 7: HESS energy flux limits (99% c.l.) for pulsed emission of the Vela pulsar (see Fig. 6 for point descriptions). The cross and open square denote limits from the Durham Mark 6 telescope (99.865% c.l., Chadwick et al. 2000), and the CANGAROO detector (95% c.l., Yoshikoshi et al. 1997), respectively. The open triangles resemble the EGRET phase-averaged spectrum (Fierro et al. 1998). The polar cap and outer gap model curves are generated according to the model of Rudak & Dyks (1999, black dotted curve) and from Hirotani et al. (2003, dashed curve), respectively. The dotted grey outer gap model curve is taken from Takata et al. (2006).

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In the text

Figure 8: HESS energy flux limits (99% c.l.) for pulsed emission of PSR B1706-44 for the on-off-pulse method (full points). The cross denotes a flux limit from the Durham group (99.865% c.l., Chadwick et al. 2000). The open triangles show the EGRET phase-averaged -ray spectrum (Thompson et al. 1996). Polar cap and outer gap model curves were calculated according to Rudak & Dyks (1999) and taken from Hirotani et al. (2003).

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In the text

	Figure 9: HESS energy flux limits (99% c.l.) for pulsed emission of PSR B1509-58 (see Fig. 6 for point descriptions). The open triangles resemble the EGRET upper limits for pulsed emission (Thompson et al. 1999). The outer gap model curve (dotted) originates from Hirotani & Shibata (2001b), Fig. 6.
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In the text

	Figure 10: Differential upper limits on the energy flux of pulsed VHE -ray emission for non--ray pulsars as measured by HESS (at 99% confidence, point descriptions as in Fig. 6).
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In the text

	Figure 11: Differential upper limits at 99% confidence on the energy flux of unpulsed VHE -ray emission for PSR J1747-2958, PSR J1801-2451 and PSR J1811-1925 ( from top to bottom) as measured by HESS.
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In the text