ANAIS (annual modulation with NaI scintillators) is a dark matter direct detection experiment consisting of 112.5 kg of NaI(Tl) detectors in operation at the Canfranc Underground Laboratory (LSC), in ...Spain, since August 2017. ANAIS' goal is to confirm or refute in a model independent way the DAMA/LIBRA positive result: an annual modulation in the low-energy detection rate having all the features expected for the signal induced by dark matter particles in a standard galactic halo. This modulation, observed for about 20 years, is in strong tension with the negative results of other very sensitive experiments, but a model-independent comparison is still lacking. By using the same target material, NaI(Tl), such a comparison is more direct and almost independent in dark matter particle and halo models. Here, we present the annual modulation analysis corresponding to three years of ANAIS data (for an effective exposure of 313.95 kg × y ), applying a blind procedure, which updates the one developed for the 1.5 years analysis, and later applied to 2 years. The analysis also improves the background modeling in the fitting of the region of interest rates. We obtain for the best fit in the 1–6 keV (2–6 keV) energy region a modulation amplitude of − 0.0034 ± 0.0042 cpd / kg / keV ( 0.0003 ± 0.0037 cpd / kg / keV ), supporting the absence of modulation in our data, and incompatible with the DAMA/LIBRA result at 3.3 (2.6) σ , for a sensitivity of 2.5 (2.7) σ . Moreover, we include two complementary analyses: a phase-free annual modulation search and the exploration of the possible presence of a periodic signal at other frequencies. Finally, we carry out several consistency checks of our result, and we update the ANAIS-112 projected sensitivity for the scheduled 5 years of operation.
Abstract
We report the results of 6 years (2013–2018) of measurements of
$$^{222}$$
222
Rn air concentration, relative humidity, atmospheric pressure and temperature in the halls A, B and C of the ...Canfranc Underground Laboratory (LSC). We have calculated all the Pearson correlation coefficients among these parameters and we have found a positive correlation between the
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Rn concentration and the relative humidity. Both correlated variables show a seasonal periodicity. The joint analysis of laboratory data and 4 years (2015–2018) of the meteorological variables outside the laboratory shows the correlation between the
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Rn concentration and the outside temperature. The collected information stresses the relevance of designing good Rn-mitigation strategies in current and future experiments at LSC; in particular, we have checked for two years (2017–2018) the good performance of the mitigation procedure of the ANAIS-112 experiment. Finally, we have monitored (2019–2021) for 2 years of live time, the radon-free air provided by the radon abatement system installed in the laboratory.
We report the results of 6 years (2013–2018) of measurements of
222
Rn air concentration, relative humidity, atmospheric pressure and temperature in the halls A, B and C of the Canfranc Underground ...Laboratory (LSC). We have calculated all the Pearson correlation coefficients among these parameters and we have found a positive correlation between the
222
Rn concentration and the relative humidity. Both correlated variables show a seasonal periodicity. The joint analysis of laboratory data and 4 years (2015–2018) of the meteorological variables outside the laboratory shows the correlation between the
222
Rn concentration and the outside temperature. The collected information stresses the relevance of designing good Rn-mitigation strategies in current and future experiments at LSC; in particular, we have checked for two years (2017–2018) the good performance of the mitigation procedure of the ANAIS-112 experiment. Finally, we have monitored (2019–2021) for 2 years of live time, the radon-free air provided by the radon abatement system installed in the laboratory.
Abstract
ANAIS is a direct dark matter detection experiment aiming at the confirmation or refutation of the DAMA/LIBRA positive annual modulation signal in the low energy detection rate, using the ...same target and technique. ANAIS–112, located at the Canfranc Underground Laboratory in Spain, is operating an array of 3×3 ultrapure NaI(Tl) crystals with a total mass of 112.5 kg since August 2017. The trigger rate in the region of interest (1-6 keV) is dominated by non-bulk scintillation events. In order to discriminate these noise events from bulk scintillation events, robust filtering protocols have been developed. Although this filtering procedure works very well above 2 keV, the measured rate from 1 to 2 keV is about 50% higher than expected according to our background model, and we cannot discard non-bulk scintillation events as responsible of that excess. In order to improve the rejection of noise events, a Boosted Decision Tree has been developed and applied. With this new PMT-related noise rejection algorithm, the ANAIS–112 background between 1 and 2 keV is reduced by almost 30%, leading to an increase in sensitivity to the annual modulation signal. The reanalysis of the three years of ANAIS–112 data with this technique is also presented.
Abstract
ANAIS-112 is a dark matter direct detection experiment that operates 112 kg of NaI(Tl) scintillators at the Canfranc Underground Laboratory (LSC, Spain). Its main goal is to test in a model ...independent way one of the most puzzling results in the present particle physics scenario: the DAMA/LIBRA observation of an annual modulation in the detection rate compatible with that expected for dark matter. This signal is in strong tension with the negative results of other very sensitive experiments. However, until recently a direct comparison using the same target material (NaI(Tl)) was lacking. ANAIS-112 has been taking data since August 2017 in stable conditions with excellent performance. Results from the first three years are compatible with the absence of modulation and incompatible with the DAMA/LIBRA measured modulation at more than 2.5
σ
C.L. This result supports the projected goal of reaching a 3
σ
sensitivity to the DAMA/LIBRA result for the scheduled five-year operation.
Abstract
The ANAIS (Annual modulation with NaI(Tl) Scintillators) experiment aims at the confirmation or refutation of the DAMA/LIBRA positive annual modulation signal in the low energy detection ...rate. ANAIS-112, consisting of nine 12.5 kg NaI(Tl) modules, is taking data since August, 2017 at the Canfranc Underground Laboratory (LSC) in Spain. Results from the analysis of three years of data are compatible with the absence of modulation. The background model developed for all nine ANAIS-112 detectors was established from commissioning data and non-blinded events in the first year of data taking. Now, background characterization is being improved profiting from the larger accumulated exposure available. Here, the background model is described and comparisons of model and measurements for energy spectra and counting rate time evolution for three-year exposure (considering different analysis conditions) are presented.
New Trends in Audiovisual Translation is an innovative and interdisciplinary collection of articles written by leading experts in the emerging field of audiovisual translation (AVT). In a highly ...accessible and engaging way, it introduces readers to some of the main linguistic and cultural challenges that translators encounter when translating films and other audiovisual productions. The chapters in this volume examine translation practices and experiences in various countries, highlighting how AVT plays a crucial role in shaping debates about languages and cultures in a world increasingly dependent on audiovisual media. Through analysing materials which have been dubbed and subtitled like Bridget Jones’s Diary, Forrest Gump, The Simpsons or South Park, the authors raise awareness of current issues in the study of AVT and offer new insights on this complex and vibrant area of the translation discipline.
The DAMA/LIBRA observation of an annual modulation in the detection rate compatible with that expected for dark matter is one of the most puzzling results in the present particle physics scenario. ...This signal is in strong tension with the negative results of other experiments. However, until recently a direct comparison using the same target material (NaI(Tl)) was lacking. ANAIS (annual modulation with NaI scintillators) is a dark matter direct detection experiment located at the Canfranc Underground Laboratory (LSC, Spain). Its main goal is to test in a model independent way the DAMA/LIBRA positive result. ANAIS-112, consisting of 112.5 kg of NaI(Tl) scintillators, was installed at the LSC in 2017 and since then is taking data smoothly with excellent performances. Here we present the results of the annual modulation analysis corresponding to three years of ANAIS data. These results are compatible with the absence of modulation and in tension with DAMA/LIBRA result. Moreover, they support our goal of reaching a 3
sensitivity to the DAMA/LIBRA result with about 5 years of data.
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