Without considering Earth magnetic field(the charged ball is only attracted by gravity), It does not emit radiation. The key point is: any charge accelerated by only one force will not emit energy. IT emits energy only when it's being decelerated. Or when it's being exerted by more than one force. A typical case is that the charge is running in circular track. The charge gains energy while being accelerated, releases energy while being decelerated. Without considering Ea