Volume 480 - International Conference on Exotic Atoms and Related Topics and Conference on Low Energy Antiprotons (EXA-LEAP2024) - Main session
Background Rejection for the ALPHA-g Anti-Hydrogen Detectors
G. Smith*  on behalf of the ALPHA collaboration
*: corresponding author
Full text: pdf
Pre-published on: March 31, 2025
Published on: —
Abstract
The ALPHA-g experiment recently made the news for the first direct measurement of the gravitational free-fall of anti-hydrogen [1]. Crucial to this milestone is a detector system capable of accurately recording the vertical position of annihilating anti-atoms, with two critical requirements: precise localization of anti-hydrogen annihilations into the “up” or “down” regions, and effective discrimination against the cosmic ray background. To accomplish this, the annihilation products are tracked using a radial time projection chamber detector, and fitted to a common
vertex. Simultaneously, a secondary barrel scintillator detector records the time of flight of these products. This timing information is used as part of a multivariate analysis to reject externally incident cosmic rays. This presentation showcases the cosmic ray background rejection used in the published measurement, as well as the calibration and analysis campaign to unlock time-of-
flight-based background rejection for forthcoming ALPHA-g measurements of the gravitational
behavior of anti-hydrogen.
DOI: https://doi.org/10.22323/1.480.0084
How to cite

Metadata are provided both in article format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in proceeding format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.