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  1. This Letter reports new results from the HAYSTAC experiment’s search for dark matter axions in our galactic halo. It represents the widest search to date that utilizes squeezing to realize subquantum limited noise. The new results cover 1.71 μ eV of newly scanned parameter space in the mass ranges 17.28 18.44 μ eV and 18.71 19.46 μ eV . No statistically significant evidence of an axion signal was observed, excluding couplings | g γ | 2.75 × | g γ KSVZ | and | g γ | 2.96 × | g γ KSVZ | at the 90% confidence level over the respective region. By combining this data with previously published results using HAYSTAC’s squeezed state receiver, a total of 2.27 μ eV of parameter space has now been scanned between 16.96 19.46 μ eV μ eV , excluding | g γ | 2.86 × | g γ KSVZ | at the 90% confidence level. These results demonstrate the squeezed state receiver’s ability to probe axion models over a significant mass range while achieving a scan rate enhancement relative to a quantum-limited experiment. Published by the American Physical Society2025 
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    Free, publicly-accessible full text available April 1, 2026
  2. Abstract CUPID, the CUORE Upgrade with Particle Identification, is a next-generation experiment to search for neutrinoless double beta decay ($$0\mathrm {\nu \beta \beta }$$ 0 ν β β ) and other rare events using enriched Li$$_{2}$$ 2 $$^{100}$$ 100 MoO$$_{4}$$ 4 scintillating bolometers. It will be hosted by the CUORE cryostat located at the Laboratori Nazionali del Gran Sasso in Italy. The main physics goal of CUPID is to search for$$0\mathrm {\nu \beta \beta }$$ 0 ν β β of$$^{100}$$ 100 Mo with a discovery sensitivity covering the full neutrino mass regime in the inverted ordering scenario, as well as the portion of the normal ordering regime with lightest neutrino mass larger than 10 meV. With a conservative background index of 10$$^{-4}$$ - 4  cts$$/($$ / ( keV$$\cdot $$ · kg$$\cdot $$ · yr$$)$$ ) , 240 kg isotope mass, 5 keV FWHM energy resolution at 3 MeV and 10 live-years of data taking, CUPID will have a 90% C.L. half-life exclusion sensitivity of$$1.8\cdot 10^{27}$$ 1.8 · 10 27  yr, corresponding to an effective Majorana neutrino mass ($$m_{\beta \beta }$$ m β β ) sensitivity of 9–15 meV, and a$$3\sigma $$ 3 σ discovery sensitivity of$$1\cdot 10^{27}$$ 1 · 10 27  yr, corresponding to an$$m_{\beta \beta }$$ m β β range of 12–21 meV. 
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    Free, publicly-accessible full text available July 1, 2026
  3. The Cryogenic Underground Observatory for Rare Events (CUORE) is a detector array comprised by 988 5 cm × 5 cm × 5 cm TeO 2 crystals held below 20 mK, primarily searching for neutrinoless double-beta decay in Te 130 . Unprecedented in size among cryogenic calorimetric experiments, CUORE provides a promising setting for the study of exotic throughgoing particles. Using the first tonne year of CUORE’s exposure, we perform a search for hypothesized (FCPs), which are well-motivated by various standard model extensions and would have suppressed interactions with matter. Across the searched range of charges e / 24 e / 2 no excess of FCP candidate tracks is observed over background, setting leading limits on the underground FCP flux with charges e / 24 e / 5 at 90% confidence level. Using the low background environment and segmented geometry of CUORE, we establish the sensitivity of tonne-scale subkelvin detectors to diverse signatures of new physics. Published by the American Physical Society2024 
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  4. null (Ed.)
  5. Abstract The Cryogenic Underground Observatory for Rare Events (CUORE) is the most sensitive experiment searching for neutrinoless double-beta decay (0 νββ ) in 130 Te. CUORE uses a cryogenic array of 988 TeO 2 calorimeters operated at ∼10 mK with a total mass of 741 kg. To further increase the sensitivity, the detector response must be well understood. Here, we present a non-linear thermal model for the CUORE experiment on a detector-by-detector basis. We have examined both equilibrium and dynamic electro-thermal models of detectors by numerically fitting non-linear differential equations to the detector data of a subset of CUORE channels which are well characterized and representative of all channels. We demonstrate that the hot-electron effect and electric-field dependence of resistance in NTD-Ge thermistors alone are inadequate to describe our detectors' energy-dependent pulse shapes. We introduce an empirical second-order correction factor in the exponential temperature dependence of the thermistor, which produces excellent agreement with energy-dependent pulse shape data up to 6 MeV. We also present a noise analysis using the fitted thermal parameters and show that the intrinsic thermal noise is negligible compared to the observed noise for our detectors. 
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