Table 3: The expected number of events $\langle E_{\rm p} \rangle$ per year in pixel lensing observations towards the M 31 galaxy for different locations of sources and lenses is shown. We consider the $100\times 70$ arcmin2 region oriented along the major axis of M 31. and exclude events occurring within a radius of 8 arcmin of the M 31 center. Sources and lenses in the M 31 bulge and disk are indicated by indices 1 and 2, while lenses in the M 31 halo and MW disk and halo by indices 3, 5 and 6. The first and second indices refer to source and lens, respectively. The mean mass of bulge and disk stars is $\sim $ $0.31~M_{\odot}$ and $\sim $ $ 0.53~M_{\odot}$, respectively. For the lenses in the M 31 and MW halos we take a mass of $\simeq $ $ 0.5~M_{\odot}$ and a MACHO fraction $f_{\rm MACHO} \simeq 20\%$.
    11 12 13 15 16 21 22 23 25 26 Overall
Model $\langle u_{\rm T} \rangle
_{\phi}$                      

Massive halo
$5.10\times 10^{-2}$ 11.9 16.0 10.7 0.8 4.2 15.9 11.7 25.4 1.7 9.3 107.5
Massive bulge   57.9 100.9 10.4 1.6 9.0 20.8 20.5 8.4 1.1 5.9 236.4
Massive disk   11.8 92.8 3.7 0.7 4.2 16.1 69.3 10.2 1.7 9.4 219.9
Reference   12.5 26.4 8.9 0.8 4.4 13.4 16.0 19.5 1.5 8.3 111.8

Reference
$1.4\times 10^{-2}$ 3.5 7.2 2.4 0.2 1.2 3.6 4.3 5.2 0.4 2.2 30.4


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