What is it about?

Electron ($e^-$) and positron ($e^+$) bunch characteristics were directly measured for the first time using wideband beam monitors (WBMs) and a detection system at the $e^+$ source of the SuperKEKB B-factory. Secondarily-generated $e^-$ and $e^+$ bunches after the $e^+$-production target were clearly identified in their dynamical capture process at locations of the WBMs under a two-bunch acceleration scheme.

Featured Image

Why is it important?

The longitudinal and transverse bunch characteristics, the time intervals between the $e^-$ and $e^+$ bunches, the bunch lengths, transverse bunch positions, and bunch charges were simultaneously separately measured for each bunch as functions of the capture phase to investigate their dynamical capture process. The results show that quite symmetric behaviors of the $e^-$ and $e^+$ bunch characteristics were clearly observed.


The new WBMs open up a new window for direct measurements of both the $e^-$ and $e^+$ bunches during their dynamical capture process and in the optimization procedure of the $e^+$ bunch intensity in multidimensional parameter spaces at any $e^+$ sources.

Dr. Tsuyoshi Suwada
High Energy Accelerator Reseach Organization (KEK)

Read the Original

This page is a summary of: First direct measurement of electron and positron bunch characteristics at the positron source of the SuperKEKB B-factory, AIP Advances, April 2023, American Institute of Physics, DOI: 10.1063/5.0145776.
You can read the full text:



The following have contributed to this page