ESS begins RF conditioning of Drift Tube Linac

The European Spallation Source (ESS) has initiated the radio frequency (RF) conditioning process for the Normal Conducting Linac (NCL) section of its accelerator. This is a critical step towards enabling the Drift Tube Linac (DTL) to handle proton beams across the initial 40 meters of the ESS accelerator.

RF conditioning involves gradually increasing RF power into the cavities until the required stable accelerating field gradient is achieved. For the DTL cavities, the target is 3 MV/m at 14 Hz with a pulse duration of 3.2 ms. Initial RF pulses were sent to DTL tanks 2, 3, and 4 after extensive installation and testing, alongside tank 1, which had previously been tested with a beam in 2022.

The ongoing RF conditioning of the DTL tanks is essential for making the NCL ready for beam operations and is scheduled to continue until April. This process includes verifying all safety functions, vacuum systems, water cooling, RF components, and control software. The established conditioning routine was developed and tested during the conditioning of DTL1 last year.

Beam commissioning, where the proton beam will travel from the ion source to a Faraday cup located after DTL4, is anticipated to begin in April and conclude by summer. The fifth and final DTL tank is slated for installation after the summer, followed by beam testing in conjunction with the superconducting linac section.