Astronomy & Astrophysics

All Figures

$\begin{figure} {\includegraphics[width=6.6cm,clip]{1566fig1.ps} } \end{figure}$ Figure 1: JHK composite image of Maffei 1 from the 2MASS Large Galaxy Atlas (Jarrett et al. 2003). The field of view is $11.9'\!\times\! 11.9'$ .
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In the text

$\begin{figure} {\includegraphics[width=7.5cm,clip]{1566fig2.ps} } \end{figure}$ Figure 2: Radial surface brightness profile of Maffei 1 in IJHK along the galaxy major axis. The I-band data are from Buta & McCall (1999) and the JHK data from the 2MASS Large Galaxy Atlas (Jarrett et al. 2003). The shifts between the curves partly reflect the chromatic extinction.
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In the text

$\begin{figure} {\includegraphics[width=14.8cm,clip]{1566fig3.ps} } \end{figure}$ Figure 3: Microlensing optical depth map near the Galactic plane of the H₂ globule cores assuming that their 3D mass density is twice that of the observed neutral hydrogen, for distant extragalactic sources ( $D_{\rm S} \gg D_{\rm L}$ ). The contours are spaced by $\Delta \tau _{-6}=0.2$ and the thick contour stands for $\tau _{-6}=0.6$ . The location of Maffei 1 is indicated by the white square. The HI data are from Hartmann & Burton (1997), Burton & Liszt (1978) and Kerr et al. (1967).
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In the text

$\begin{figure} {\includegraphics[width=8cm,clip]{1566fig4.ps} } \end{figure}$ Figure 4: Expected number of resolvable stars per unit solid angle in Maffei 1 as a function of angular radius a along the major axis of the galaxy and exposure time, for two combinations of telescopes and detectors, including adaptive optics in the K-band, and using the surface brightness profiles plotted in Fig. 2. The dotted lines are for $t_{\rm exp}=1,2,4,8,16,32$ s for Gemini/NIRI, and for $t_{\rm exp}=1.25,2.5,5,10,20,40$ min for HST/ACS, and the solid lines represent the upper limits resulting from Eq. (19). The detection threshold is set to 3 sigmas. The adopted telescope zeropoints, sky backgrounds and seeing angles are listed in Table 2.
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In the text

$\begin{figure} {\includegraphics[width=8cm,clip]{1566fig5.ps} } \end{figure}$ Figure 5: Location of four optimal HST/ACS fields in Maffei 1 for the search of classical lensing events. The full, dashed and dotted lines represent the isophotes where the I-band surface density of resolvable stars $N_{\rm res}$ is maximum, $80\%$ of maximum, and $50\%$ of maximum respectively. The dots represent bright guide stars for near-IR adaptive optic observations, obtained from the STSI Guide Star Catalogue I.
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In the text

$\begin{figure} {\includegraphics[width=8cm,clip]{1566fig6.ps} } \end{figure}$ Figure 6: Expected number of detectable pixel lensing events per arcmin² in Maffei 1 as a function of angular radius a along the galaxy major axis, when observing 10 h with various combinations of telescopes and detectors, and for the surface brightness profiles displayed in Fig. 2. The signal-to-noise threshold is $Q_{\rm min}=5$ , and AO indicates the use of adaptive optics. The observing parameters are specified in Table 2.
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In the text

$\begin{figure} {\includegraphics[width=6.6cm,clip]{1566fig1.ps} } \end{figure}$	Figure 1: JHK composite image of Maffei 1 from the 2MASS Large Galaxy Atlas (Jarrett et al. 2003). The field of view is $11.9'\!\times\! 11.9'$ .
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$\begin{figure} {\includegraphics[width=7.5cm,clip]{1566fig2.ps} } \end{figure}$	Figure 2: Radial surface brightness profile of Maffei 1 in IJHK along the galaxy major axis. The I-band data are from Buta & McCall (1999) and the JHK data from the 2MASS Large Galaxy Atlas (Jarrett et al. 2003). The shifts between the curves partly reflect the chromatic extinction.
Open with DEXTER