Kinematics Calibration and Excitation Energy Reconstruction for Solenoidal Spectrometers

TL;DR

This paper presents a new calibration and reconstruction method for solenoidal spectrometers that improves real-time analysis of excitation energy and scattering angles, especially at small angles, using energy-position data.

Contribution

It introduces an analytical inverse transformation technique based on relativistic kinematics for accurate excitation energy reconstruction in solenoidal spectrometers.

Findings

Effective handling of forward-angle data

Enhanced accuracy over traditional methods

Demonstrated with 25Mg(d,p) reaction data

Abstract

This work introduces a novel method for reconstructing excitation energy and center-of-mass scattering angle from energy-position data in solenoidal spectrometers, addressing challenges posed by non-linearities at small scattering angles. The approach employs a robust calibration of experimental energy-position data using known excited states, followed by an analytical inverse transformation based on relativistic kinematics and cyclotron motion. Integrated into the HELIOS online analysis routines, this method enables real-time generation of excitation energy spectra and angular distributions during experiments, improving efficiency and accuracy over traditional projection-based methods. The method's effectiveness is demonstrated using the 25Mg(d,p) reaction, highlighting its ability to handle forward-angle data and produce precise kinematic reconstructions.