A method for producing a silicon ingot, the method comprising: withdrawing a seed crystal from a melt comprising an amount of melted silicon in a crucible to form the silicon ingot, the crucible enclosed in a vacuum chamber containing a cusped magnetic field; and regulating at least one process parameter, wherein the at least one process parameter is regulated in at least two stages, the at least two stages comprising: a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length; and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length; wherein regulating the at least one process parameter during the second stage comprises at least one of: reducing a crystal rotation rate relative to the crystal rotation rate during the first stage; reducing a crucible rotation rate relative to the crucible rotation rate during the first stage; and increasing a magnetic field strength relative to the magnetic field strength during the first stage, characterized in that the first stage is an intermediate growth stage and the second stage is a late body growth stage, and wherein a transition from the intermediate growth stage to the late body growth stage is identified by determining the depth of the melt within the crucible or by determining that less than about 50% of the initial mass of the melt is left in the crucible. withdrawing a seed crystal from a melt comprising an amount of melted silicon in a crucible to form the silicon ingot, the crucible enclosed in a vacuum chamber containing a cusped magnetic field; and regulating at least one process parameter, wherein the at least one process parameter is regulated in at least two stages, the at least two stages comprising: a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length; and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length; a first stage corresponding to formation of the silicon ingot up to an intermediate ingot length; and a second stage corresponding to formation of the silicon ingot from the intermediate ingot length to the total ingot length; wherein regulating the at least one process parameter during the second stage comprises at least one of: reducing a crystal rotation rate relative to the crystal rotation rate during the first stage; reducing a crucible rotation rate relative to the crucible rotation rate during the first stage; and increasing a magnetic field strength relative to the magnetic field strength during the first stage, reducing a crystal rotation rate relative to the crystal rotation rate during the first stage; reducing a crucible rotation rate relative to the crucible rotation rate during the first stage; and increasing a magnetic field strength relative to the magnetic field strength during the first stage, characterized in that the first stage is an intermediate growth stage and the second stage is a late body growth stage, and wherein a transition from the intermediate growth stage to the late body growth stage is identified by determining the depth of the melt within the crucible or by determining that less than about 50% of the initial mass of the melt is left in the crucible. <EOS>