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In order to determine an upper bound for the mass of the massive compact haloobjets (MACHOs) we use the halo binaries contained in a recent catalog (Allen\& Monroy-Rodr\'{\i}guez 2013). To dynamically model their interactions withmassive perturbers a Monte Carlo simulation is conducted, using an impulsiveapproximation method and assuming a galactic halo constituted by massiveparticles of a characteristic mass. The results of such simulations arecompared with several subsamples of our improved catalog of candidate halo widebinaries. In accordance with Quinn et al. (2009) we also find our results to bevery sensitive to the widest binaries. However, our larger sample, togetherwith the fact that we can obtain galactic orbits for 150 of our systems, allowsa more reliable estimate of the maximum MACHO mass than that obtainedpreviously. If we employ the entire sample of 211 candidate halo stars weobtain an upper limit of $112 M_\sun$. However, using the 150 binaries in ourcatalog with computed galactic orbits we are able to refine our fittingcriteria. Thus, for the 100 most halo-like binaries we obtain a maximum MACHOmass of $21-68 M_\sun$. Furthermore, we can estimate the dynamical effects ofthe galactic disk using binary samples that spend progressively shorter timeswithin the disk. By extrapolating the limits obtained for our most reliable-albeit smallest- sample we find that as the time spent within the disk tendsto zero the upper bound of the MACHO mass tends to less than $5 M_\sun$. Thenon-uniform density of the halo has also been taken into account, but the limitobtained, less than $5 M_\sun$, does not differ much from the previous one.Together with microlensing studies that provide lower limits on the MACHO mass,our results essentially exclude the existence of such objects in the galactichalo.

The end of the MACHO era- revisited: new limits on MACHO masses from halo wide binaries