Solar-axion interaction rates in NaI, CsI and Xe scintillators via the axio-electric effect were calculated. A table is presented with photo-electric and axio-electric cross sections, solar-axion ...fluxes, and the interaction rates from 2.0 to 10.0 keV. The results imply that annual-modulation data of large NaI and CsI arrays, and large Xe scintillation detectors, might be made sensitive enough to probe coupling to photons at levels required to explain axion–photon oscillation phenomena proposed to explain the survival of high-energy photons traveling cosmological distances. The DAMA/LIBRA data are used to demonstrate the power of the model-independent annual modulation due to the seasonal variation in the earth-sun distance.
The distribution of the zeros of the partition function in the complex temperature plane (Fisher zeros) of the two-dimensional
Q-state Potts model is studied for non-integer
Q. On
L×
L self-dual ...lattices studied (
L⩽8), no Fisher zero lies on the unit circle
p
0=e
i
θ
in the complex
p=(
e
βJ−1)/
Q
plane for
Q<1, while some of the Fisher zeros lie on the unit circle for
Q>1 and the number of such zeros increases with increasing
Q. The ferromagnetic and antiferromagnetic properties of the Potts model are investigated using the distribution of the Fisher zeros. For the Potts ferromagnet we verify the den Nijs formula for the thermal exponent
y
t
. For the Potts antiferromagnet we also verify the Baxter conjecture for the critical temperature and present new results for the thermal exponents in the range 0<
Q<3.
The ESR absorption spectrum of Mn2+ ions at Zn positions has been studied in the incommensurate phase of Rb2ZnCl4. It is known that Rb2ZnCl4 crystals exhibit an incommensurate phase between ...temperatures Ti = 303 K and T1 =192 K. The form and the temperature dependence of ESR spectra are in good agreement with the predictions of the phase soliton theory. The parameters h/ and h2 determining the magnetic resonance field show, as expected, a power law as a function of the temperature. A modified superposition model was used to estimate the modulation amplitude of the incommensurate phase, and the principal axis of the zero field splitting D.
Abstract
The CUORE experiment is a large bolometric array searching for the lepton number violating neutrino-less double beta decay (
$$0\nu \beta \beta $$
0
ν
β
β
) in the isotope
$$\mathrm ...{^{130}Te}$$
130
Te
. In this work we present the latest results on two searches for the double beta decay (DBD) of
$$\mathrm {^{130}Te}$$
130
Te
to the first
$$0^{+}_2$$
0
2
+
excited state of
$$\mathrm {^{130}Xe}$$
130
Xe
: the
$$0\nu \beta \beta $$
0
ν
β
β
decay and the Standard Model-allowed two-neutrinos double beta decay (
$$2\nu \beta \beta $$
2
ν
β
β
). Both searches are based on a 372.5 kg
$$\times $$
×
yr TeO
$$_2$$
2
exposure. The de-excitation gamma rays emitted by the excited Xe nucleus in the final state yield a unique signature, which can be searched for with low background by studying coincident events in two or more bolometers. The closely packed arrangement of the CUORE crystals constitutes a significant advantage in this regard. The median limit setting sensitivities at 90% Credible Interval (C.I.) of the given searches were estimated as
$$\mathrm {S^{0\nu }_{1/2} = 5.6 \times 10^{24} \, \mathrm {yr}}$$
S
1
/
2
0
ν
=
5.6
×
10
24
yr
for the
$${0\nu \beta \beta }$$
0
ν
β
β
decay and
$$\mathrm {S^{2\nu }_{1/2} = 2.1 \times 10^{24} \, \mathrm {yr}}$$
S
1
/
2
2
ν
=
2.1
×
10
24
yr
for the
$${2\nu \beta \beta }$$
2
ν
β
β
decay. No significant evidence for either of the decay modes was observed and a Bayesian lower bound at
$$90\%$$
90
%
C.I. on the decay half lives is obtained as:
$$\mathrm {(T_{1/2})^{0\nu }_{0^+_2} > 5.9 \times 10^{24} \, \mathrm {yr}}$$
(
T
1
/
2
)
0
2
+
0
ν
>
5.9
×
10
24
yr
for the
$$0\nu \beta \beta $$
0
ν
β
β
mode and
$$\mathrm {(T_{1/2})^{2\nu }_{0^+_2} > 1.3 \times 10^{24} \, \mathrm {yr}}$$
(
T
1
/
2
)
0
2
+
2
ν
>
1.3
×
10
24
yr
for the
$$2\nu \beta \beta $$
2
ν
β
β
mode. These represent the most stringent limits on the DBD of
$$^{130}$$
130
Te to excited states and improve by a factor
$$\sim 5$$
∼
5
the previous results on this process.
It is assumed that axion-like Nambu Goldstone bosons exist and are created in the sun by Primakoff conversion of photons in the Coulomb fields of nuclei. Detection rates are calculated in germanium ...detectors due to the coherent conversion of axions to photons in the lattice when the incident angle fulfills the Bragg condition for a given crystalline plane. The rates are correlated with the relative positions of the sun and detector yielding a definite recognizable sub-diurnal temporal pattern. A major experiment is proposed based on a large detector array.
The Cryogenic Underground Observatory for Rare Events (CUORE) is the most massive bolometric experiment searching for neutrino-less double beta (0νββ) decay. The detector consists of an array of 988 ...TeO2 crystals (742 kg) arranged in a compact cylindrical structure of 19 towers. This paper will describe the CUORE experiment, including the cryostat, and present the detector performance during the first year of running. Additional detail will describe the effort made in improving the energy resolution in the 130Te 0νββ decay region of interest (ROI) and the suppression of backgrounds. A description of work to lower the energy threshold in order to give CUORE the sensitivity to search for other rare events, such as dark matter, will also be provided.
Abstract
We report on a search for double beta decay of
$$^{130}\hbox {Te}$$
130
Te
to the first
$$0^{+}$$
0
+
excited state of
$$^{130}\hbox {Xe}$$
130
Xe
using a
$$9.8\,\hbox {kg}\cdot \hbox {yr}$$
...9.8
kg
·
yr
exposure of
$$^{130}\hbox {Te}$$
130
Te
collected with the CUORE-0 experiment. In this work we exploit different topologies of coincident events to search for both the neutrinoless and two-neutrino double beta decay modes. We find no evidence for either mode and place lower bounds on the half-lives:
$$T^{0\nu }_{0^+_1}>7.9\cdot 10^{23}\hbox {yr}$$
T
0
1
+
0
ν
>
7.9
·
10
23
yr
and
$$T^{2\nu }_{0^+_1}>2.4\cdot 10^{23}\hbox {yr}$$
T
0
1
+
2
ν
>
2.4
·
10
23
yr
(
$$90\%\,\hbox {CL}$$
90
%
CL
). Combining our results with those obtained by the CUORICINO experiment, we achieve the most stringent constraints available for these processes:
$$T^{0\nu }_{0^+_1}>1.4\cdot 10^{24}\hbox {yr}$$
T
0
1
+
0
ν
>
1.4
·
10
24
yr
and
$$T^{2\nu }_{0^+_1}>2.5\cdot 10^{23}\hbox {yr}$$
T
0
1
+
2
ν
>
2.5
·
10
23
yr
(
$$90\%\,\hbox {CL}$$
90
%
CL
).
The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for neutrinoless double beta decay that has been able to reach the 1-ton scale. The detector ...consists of an array of 988 TeO2 crystals arranged in a cylindrical compact structure of 19 towers. The construction of the experiment and, in particular, the installation of all towers in the cryostat was completed in August 2016 and data taking started in spring 2017. In this contribution the achievement of the commissioning phase and the performance of the detector and the cryostat during the first physics run will be presented.
•Improvement in the reduction of the noise induced by the mechanic vibration of the Pulse Tubes system.•Improvement of the energy resolution between two data taking periods as a result of a dedicated detector optimization campaign.•Plans on how to lower the trigger threshold to identify very low energy signals and enhance detector sensitivity to Dark Matter.
We report CUPID is a next-generation tonne-scale bolometric neutrinoless double beta decay experiment that will probe the Majorana nature of neutrinos and discover lepton number violation in case of ...observation of this singular process. CUPID will be built on experience, expertise and lessons learned in CUORE and will be installed in the current CUORE infra-structure in the Gran Sasso underground laboratory. The CUPID detector technology, successfully tested in the CUPID-Mo experiment, is based on scintillating bolometers of Li2MoO4 enriched in the isotope of interest 100Mo. In order to achieve its ambitious science goals, the CUPID collaboration aims to reduce the backgrounds in the region of interest by a factor 100 with respect to CUORE. This performance will be achieved by introducing the high efficient α/β discrimination demonstrated by the CUPID-0 and CUPID-Mo experiments, and using a high transition energy double beta decay nucleus such as 100Mo to minimize the impact of the gamma background. CUPID will consist of about 1500 hybrid heat-light detectors for a total isotope mass of 250 kg. The CUPID scientific reach is supported by a detailed and safe background model based on CUORE, CUPID-Mo and CUPID-0 results. The required performances have already been demonstrated and will be presented.
The Cryogenic Underground Observatory for Rare Events (CUORE) is a detector array comprised by 988 5\(\;\)cm\(\times\)5\(\;\)cm\(\times\)5\(\;\)cm TeO\(_2\) crystals held below 20 mK, primarily ...searching for neutrinoless double-beta decay in \(^{130}\)Te. Unprecedented in size amongst cryogenic calorimetric experiments, CUORE provides a promising setting for the study of exotic through-going particles. Using the first tonne-year of CUORE's exposure, we perform a search for hypothesized fractionally charged particles (FCPs), which are well-motivated by various Standard Model extensions and would have suppressed interactions with matter. No excess of FCP candidate tracks is observed over background, setting leading limits on the underground FCP flux with charges between \(e/24-e/5\) at 90\% confidence level. Using the low background environment and segmented geometry of CUORE, we establish the sensitivity of tonne-scale sub-Kelvin detectors to diverse signatures of new physics.
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