MDPCT1 quench data and performance analysis

TL;DR

This paper analyzes the quench data and diagnostic techniques of the MDPCT1 Nb3Sn dipole magnet, highlighting its performance, degradation issues, and the evolution of measurement methods to improve future magnet development.

Contribution

It introduces new measurement and analysis techniques for diagnosing magnet performance and degradation in a four-layer Nb3Sn dipole magnet.

Findings

Inner coils performed well with minimal quenches at high fields.

Outer coils showed degradation over testing cycles.

Diagnostic techniques evolved to better understand magnet failures.

Abstract

MDPCT1 is a four-layer cos-theta Nb3Sn dipole demonstrator developed and tested at FNAL in the framework of the U.S. Magnet Development Program. The magnet reached record fields for accelerator magnets of 14.1 T at 4.5 K in the first test and 14.5 T at 1.9 K in the second test and then showed large degradation. While its inner coils performed exceptionally well with only two quenches up to 14.5 T and no evidence of degradation, the outer coils degraded over the course of testing. By adopting new measurement and analysis techniques at FNAL we are discussing in detail what happened. Both success and failure in our diagnostics are discussed. The evolution of techniques over the course of two tests (and three thermal cycles) shows the path to address challenges brought by the first four-layer magnet tested at FNAL. This paper presents the analysis of quench data along with diagnostic features and complementary measurements taken in support of the magnet performance analysis.