Can DAMA's background subtraction create a spurious yearly modulation? · revision history

Revision 2

Accepted · core change · record

Changes against revision 1:

Title
Can DAMA's background subtraction create a spurious yearly modulation?
Plain
DAMA subtracts each year's average rate before looking for a yearly wave; if the true rate drifts slowly, this step can manufacture a wave that is not there. The question is whether this explains all or part of the signal.
Precise · changed · core
Revision 1: DAMA forms residuals by subtracting the annual mean rate per energy bin, cycle by cycle (roughly September to September). For a time-dependent background $B(t)$ (e.g., decaying cosmogenic or radiogenic components, or slow gain drift), this procedure induces a sawtooth residual whose fit to $A$ cos(2 pi (t - t0)/1 yr) can give a nonzero A with a phase that depends on $\mathrm{d}B/\mathrm{d}t$. An answer is a quantitative yes or no: whether a background evolution consistent with DAMA's published spectra and stability data reproduces the reported amplitude and phase.
Revision 2: DAMA forms residuals by subtracting the annual mean rate per energy bin, cycle by cycle (roughly September to September). For a time-dependent background $B(t)$ (e.g., decaying cosmogenic or radiogenic components, or slow gain drift), this procedure induces a sawtooth residual whose fit to $A$ $\mathrm{cos}(2 \pi (t - t0)/1\,\mathrm{yr})$ can give a nonzero A with a phase that depends on $\mathrm{d}B/\mathrm{d}t$. An answer is a quantitative yes or no: whether a background evolution consistent with DAMA's published spectra and stability data reproduces the reported amplitude and phase.
Settled by
Analysis of DAMA's absolute, non-subtracted single-hit rate versus time per energy bin, or a full forward model of the DAMA background evolution fitted to their data.
Kind
well-posed
Answer type
yes-no
References
(empty)
Literature status
contested
Status note
Buttazzo, Panci, Rossi and Strumia (JHEP 2020) showed the mechanism can produce a modulation, and COSINE-100 (Sci. Rep. 2023) showed that applying the DAMA method to COSINE-100 data induces an artificial modulation; DAMA and Messina, Nardecchia and Piacentini (JCAP 2020) dispute that it applies to DAMA data.
Posed since
2020

Decisions