# PDFSense: Mapping the PDF sensitivity of future facilities (HL-LHC, LHeC, and EIC)

## TL;DR

This paper evaluates the sensitivity of future high-energy physics facilities to parton distribution functions (PDFs) using the PDFSense framework, highlighting their unique and complementary roles in exploring hadron structure.

## Contribution

It applies the PDFSense framework to assess the PDF sensitivity of HL-LHC, LHeC, and EIC, revealing their distinct and complementary impacts on probing QCD and hadron structure.

## Key findings

- Each facility uniquely influences specific kinematic regions.
- Facilities show complementary sensitivities to collinear quantities.
- Potential for mutual reinforcement among future experiments.

## Abstract

Particle and nuclear physics are moving toward a new generation of experiments to stress-test the Standard Model (SM), search for novel degrees of freedom, and comprehensively map the internal structure of hadrons. Due to the complex nature of QCD and wide array of past, present, and possible future experiments, measurements taken at these next-generation facilities will inhabit an expansive space of high-energy data. Maximizing the impact of each future collider program will depend on identifying its place within this sprawling landscape. As an initial exploration, we use the recently-developed PDFSense framework to assess the PDF sensitivity of two future high-energy facilities --- the high-luminosity upgrade to the LHC (HL-LHC) and the Large Hadron-electron Collider (LHeC) proposal --- as well as the electron-ion collider (EIC) proposed to map the few-GeV quark-hadron transition region. We report that each of these experimental facilities occupies a unique place in the kinematical parameter space with specialized pulls on particular collinear quantities. As such, there is a clear complementarity among these programs, with an opportunity for each to mutually reinforce and inform the others.