  The Large Hadron Collider (LHC) at CERN will see an upgraded hardware
configuration which will bring a new era of physics data taking and related
computational challenges. To this end, it is necessary to exploit the ever
increasing variety of computational architectures, featuring GPUs from multiple
vendors and new accelerators. Performance portable frameworks, like SYCL, allow
to offload the computational work on non-CPU resources, while retaining their
performance, without the need to maintain different implementations of the same
code. The High Energy Physics (HEP) community employs a wide variety of
algorithms and tools for accelerators, but it still lacks a streamlined
coherent approach that can target many use cases without compromising the
usability aspect. In this paper, we present our efforts in creating GenVectorX,
a C++ package that provides classes and functionalities to represent and
manipulate particle events using the SYCL programming model. The SYCL-based
implementation exhibits comparable performance and scalability as the CUDA
implementation when targeting NVIDIA GPUs.
