Upgrades of the Tevatron electron lens

This paper will describe the main upgrades of the Tevatron Electron Lens (TEL) during the year 2003. The bending angle of the electron beam entrance and exit to the main solenoid will be decreased from 90 degrees to 53 degrees and three more solenoids will be added to each of the two bends, which will allow us to control the electron beam size more freely. A new gun will also be installed which will give us a Gaussian transverse beam distribution in addition to the flat beam with much smoother edge to minimize the nonlinear effect of the beam-beam force. In addition, a new BPM system will be installed to let us have more precise beam position measurements for proton, antiproton and electron beams. A knife-edge beam profile measurement system will replace the space-consuming scanning wires. We expect that these upgrades will improve the ability to increase the lifetime of the (anti)proton beam during beam-beam compensation operation.