COSINE-100 Full Dataset Challenges the Annual Modulation Signal of DAMA/LIBRA

TL;DR

The COSINE-100 experiment, using sodium iodide detectors over 6.4 years, found no evidence of the annual modulation signal claimed by DAMA/LIBRA, challenging its dark matter interpretation with high confidence.

Contribution

This study provides a model-independent test with improved calibration and background modeling, offering a significant challenge to the DAMA/LIBRA dark matter claim.

Findings

No evidence of annual modulation signal in COSINE-100 data

Results challenge the DAMA/LIBRA dark matter interpretation

Confidence level exceeds 3 sigma against DAMA/LIBRA claim

Abstract

For over 25 years, the DAMA/LIBRA collaboration has claimed to observe an annual modulation signal, suggesting the existence of dark matter interactions. However, no experiment employing different target materials has observed a dark matter signal consistent with their result. To address this puzzle, the COSINE-100 collaboration conducted a model-independent test using sodium iodide crystal detectors, the same target material as DAMA/LIBRA. Analyzing data collected over 6.4 years by the effective mass of 61.3 kg, with improved energy calibration and time-dependent background modeling, we found no evidence of an annual modulation signal, challenging the DAMA/LIBRA result with a confidence level greater than 3$\sigma$. This finding represents a substantial step toward resolving the long-standing debate surrounding DAMA/LIBRA's dark matter claim, indicating that the observed modulation is unlikely to be caused by dark matter interactions.