All Figures

$\begin{figure} \par\includegraphics[width=8.4cm,clip]{4336f1.eps}\end{figure}$ Figure 1: Spectral energy distribution at an angle of $\theta = 80^\circ$ relative to the field direction for the post-shock emission region on a 0.6 $M_{\odot }$ white dwarf at a distance D=10 pc with field strength $\vert{\vec B}\vert=30$ MG, area A=4 $\times$ 10¹⁶ cm², and mass flow densities of $\dot m=1~\mbox{${\rm g~cm}^{-2}~{\rm s}^{-1}$ }$ (dashed curve) and $0.1~\mbox{${\rm g~cm}^{-2}~{\rm s}^{-1}$ }$ (solid curve) (Fischer & Beuermann 2001, their Fig. 9). For comparison, a blackbody with temperature T=10⁴ K and the same emitting area is shown (dot-dashed curve).
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8.4cm,clip]{4336f2.eps}\end{figure}$ Figure 2: Example for the relation between intrinsic spectral flux $F_{\rm wd}$ of the unheated atmosphere of the white dwarf (dotted curve), the low-temperature irradiation $F_{\rm in}$ (dashed curve), and the outgoing flux $F_{\rm out}$ of the heated atmosphere (solid curve).
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8.15cm,clip]{4336f3a.eps}\hspace*{5mm} \includegraphics[angle=270,width=8.05cm,clip]{4336f3b.eps}\end{figure}$ Figure 3: Emerging spectral flux ( left) and temperature stratification ( right) for atmospheres isotropically irradiated with five different levels of the 10⁴ K blackbody-like spectral flux with 1.8, 3.1, 6.7, 17.2, and 30.5 times the integrated flux $F_{\rm wd}$ of the 2 $\times$ 10⁴ K white dwarf atmosphere (solid curves, from bottom to top). Also shown is the spectral flux ( left) and the temperature stratification ( right) of the un-irradiated white dwarf (dotted curves).
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8.35cm,clip]{4336f4a.eps}\hspace*{5mm} \includegraphics[angle=270,width=8.35cm,clip]{4336f4b.eps}\end{figure}$ Figure 4: Directional fluxes at emission angles $\theta =0^\circ$ (looking perpendicular into the irradiated atmosphere, left panel) and $\theta =84^\circ$ (looking under a grazing angle into the atmosphere, right panel) relative to the radial direction for irradiation at $\mu =1.0$ ( $\vartheta =0^\circ$ , solid curves) and $\mu =0.1$ ( $\vartheta =84^\circ$ , dashed curves), shown for two levels of the incident flux, $1.0~F_{\rm wd}$ and $6.7~F_{\rm wd}$ (lower and upper set of curves).
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In the text

$\begin{figure} \par\includegraphics[height=3.35cm,width=3.35cm,clip]{4336f5a.eps... ...{3mm} \includegraphics[height=3.35cm,width=4.75cm,clip]{4336f5d.eps}\end{figure}$ Figure 5: Left: array of surface elements used in calculating models of white dwarfs irradiated by an extended source at a height $h=0.1~R_{\rm wd}$ above the photosphere, shown for phases $\phi =0$ ( left) and $\phi =0.5$ ( right). Center: definition of angles $\alpha$ and $\vartheta$ . Right: irradiation of a single surface element by an extended source of area A at height h above the photosphere. $\theta$ indicates the direction to the observer.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8.4cm,clip]{4336f6.eps}\end{figure}$ Figure 6: Effective temperature in the large irradiation-heated spot on a 0.6 $M_{\odot }$ white dwarf as a function of the angular distance $\alpha$ of the irradiated surface element from the center of the source. Irradiation by a point source (solid curves) or an extended source of $0.3~R_{\rm wd}$ radius with $R_{\rm wd}=8.6$ $\times$ 10⁸ cm (dashed curves) was considered, both located at a height of $0.1~R_{\rm wd}$ . The luminosity is 10³² for the lower curves and 10³³ ${\rm erg~s}^{-1}$ for the upper curves. The horizontal dotted curve is for the unheated white dwarf.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8.05cm,clip]{4336f7.eps}\end{figure}$ Figure 7: HST/GHRS spectrum of AM Her in the January 1997 high state at orbital phases $\phi =0.1$ (heated polar cap in front) and $\phi =0.5$ (heated polar cap at horizon). The model spectra are for irradiation by an isotropically emitting source of 7.7 $\times$ 10³² ${\rm erg~s}^{-1}$ with radius $0.3~R_{\rm wd}$ located at a height $0.1~R_{\rm wd}$ and for a distance of AM Her of D=79 pc. The contribution by the accretion stream (dashed curve) and the spectral flux of the unheated white dwarf (dotted curve, added to the dashed curve) are included for comparison. For the definition of the orbital phase see Gänsicke et al. (1998).
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8.4cm,clip]{4336f2.eps}\end{figure}$	Figure 2: Example for the relation between intrinsic spectral flux $F_{\rm wd}$ of the unheated atmosphere of the white dwarf (dotted curve), the low-temperature irradiation $F_{\rm in}$ (dashed curve), and the outgoing flux $F_{\rm out}$ of the heated atmosphere (solid curve).
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