Status of muon acceleration (A. Verdier)
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No work has been done since january 2001. There exist one "official" design 
with several question marks and one proposal which needs a serious study.
 
1 Official design. It was done by E. Keil at the end of the 90's. The muon
    acceleration is performed with two RLA's. It's not clear why two RLA's 
    are necessary. The basic assumption under this design is the use of the
    LEP RF system. This has serious consequences that the three acceptances
    are limitated to the rather low values of 0.1eV.s in the longitudinal 
    plane (frequency of 352MHz and maximum field of 7.5MV/m) and 0.016PI rad.m
    in both transverse planes (iris radius and cavity length). 
    Only the second RLA was designed. It features vertical spreaders. It  
    was not tested with trajectory simulation because we do not have a working
    code at CERN.
    The first RLA was a mere copy of a design for the US "study one"
    by C. Johnstone, as no solution was found at CERN. As the LEP cavities
    did not fit the cell length, 200MHz cavities had to be used.
    A clear outcome of this study it is that the LEP cavities are not suited 
    to the Neutrino Factory project.

2 AV proposal (2001). A single RLA was proposed as it can be shown that the
    beam size decreases during acceleration provided the RF cells can be
    matched to the arcs. 200 MHz cavities are used. Their maximum field could
    be as high as 15MV/m. However 12MV/m are sufficient. 
    The transverse acceptance can be as high as 0.07PI rad.m (pipe radius
    of 0.18m and one RF wave length between cavities). According to a
    simulation presented by A. Bogacz at NuFact02, the longitudinal 
    acceptance could be as high as 0.7eV.s. A serious check of this number
    is necessary.
    Some more work is necessary for this proposal concerning the design of
    the spreaders, the isochronous arcs and the injection system.The 
    simulation needs work on the code as mentioned above.