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   PR # 21513
    The discovery of the Galactic Center (GC) annihilator of positrons   
    (1E1740.7-2742) was a highlight of gamma-ray astronomy. But the      
    object seems not to be unique since three other have been discovered,
    exhibiting positron annihilation signatures; Among them,is EXS       
    1737-2958 with its double backscattered annihilation (102 keV). We   
    propose here i) to search for a X-ray counterpart to EXS source,ii)  
    to correlate X-ray observations with radio and gamma-rays (these     
    observations in other wavelengths having already been selected). This
    study is primordial to set up a new class of object: micro-quasars,  
    with radio jets, QPO's, gamma-ray emission and low energy variable   
    X-ray emission.                                                      
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