Transverse phase space characterization and reconstruction in a beam test stand at KOMAC

A slit emittance meter is developed at Korea Multipurpose Accelerator Complex (KOMAC) for measuring the 4D transverse beam phase space distribution. This measurement is crucial for assessing cross-plane correlations that impact accelerator performance. Using the slit emittance meter, we performed detailed slit scans at the Beam Test Stand (BTS) to characterize the 4D beam phase space. To verify the integrity of the slit emittance meter, we compare the slit scan results with the reconstructed sub-dimensional projected beam phases from the 4D phase space slit data. The reconstruction study demonstrates the consistency between the 4D phase space distribution measurements and its sub-dimensional phase space projections. The quadrupole magnet (quad) scan measurement is also conducted, revealing that the slit scan tend to underestimates beam emittance. This study demonstrates that the slit emittance meter is adept at characterizing the core beam distribution and cross-coupling correlations in transverse phase space. Additionally, it emphasizes that conducting a complementary quad scan is essential to achieve accurate determination of the beam emittance.