Nor should you (be able to equate the two). Very roughly speaking, temperature is akin to a measure of the average energy density. Joule is a measure of energy and watt is a measure of energy per unit time. So, they give you a measure of how fast they delivered the energy (in terawatts), how much energy was delivered (in megajoules) but this does not tell us anything about the temperature at which the sample was heated since we don't know the size of the target.