Application of exogenous plant growth regulators was examined as a viable technique to increase the efficiency of plant metal extraction from contaminated soils. The aim of this study was to ...investigate the alteration of Ni phytoextraction by Alyssum murale, a Ni hyperaccumulator, following the application of cytokinins. The following parameters were investigated: Ni accumulation, plant growth, gas exchange, stomata behavior and the concentration of nonprotein thiols (glutathione, y-Glu-Cys, and phytochelatins). In a pot experiment, A. murale plants grown in a serpentine soil were treated with a mix of naturally occurring cytokinins. Results showed that Ni accumulation in plants ranged from 4000 to 7000 mg kg⁻¹ confirming the hyper-accumulation ability from the soil used. Cytokinin treatments produced a significant increase in plant biomass and transpiration rate whereas no significant variation in Ni accumulation or the concentration of non-protein thiols was observed. The results suggest that A. murale is a plant species sensitive to cytokinin treatment and that cytokinin treatment is potentially useful in increasing the phytoextraction capability by increasing biomass. Moreover, for first time, evidence was obtained that the Ni hyperaccumulation mechanism is independent of water flux and transpiration rate.
At present the results in the field of direct dark matter search are in tension: the positive claim of DAMA/LIBRA versus null results from other experiments. However, the comparison of the results of ...different experiments involves model dependencies, in particular because of the different target materials in use. The COSINUS R&D project aims to operate NaI as a cryogenic calorimeter. Such a detector would not only allow for a direct comparison to DAMA/LIBRA, but would also provide a low(er) nuclear recoil threshold and particle discrimination.
Low temperature thermal detectors with particle identification capabilities are among the best detectors for next generation experiments for the search of neutrinoless double beta decay. Thermal ...detectors allow to reach excellent energy resolution and to optimize the detection efficiency, while the possibility to identify the interacting particle allows to greatly reduce the background. Tellurium dioxide is one of the favourite compounds since it has long demonstrated the first two features and could reach the third through Cherenkov emission tagging 1. A new generation of cryogenic light detectors are however required to detect the few Cherenkov photons emitted by electrons of few MeV energy. Preliminary measurements with new Si light detectors demonstrated a clear event-by-event discrimination between alpha and beta/gamma interactions at the 130Te neutrinoless double beta decay Q-value (2528 keV).
A
bstract
Production cross-sections of prompt charm mesons are measured using data from
pp
collisions at the LHC at a centre-of-mass energy of 5 TeV. The data sample corresponds to an integrated ...luminosity of 8
.
60 ± 0
.
33 pb
−1
collected by the LHCb experiment. The production cross-sections of
D
0
,
D
+
,
D
s
+
, and
D
∗+
mesons are measured in bins of charm meson transverse momentum,
p
T
, and rapidity,
y
. They cover the rapidity range 2
.
0
< y <
4
.
5 and transverse momentum ranges 0
< p
T
<
10 GeV
/c
for
D
0
and
D
+
and 1
< p
T
<
10 GeV
/c
for
D
s
+
and
D
∗+
mesons. The inclusive cross-sections for the four mesons, including charge-conjugate states, within the range of 1
< p
T
<
8 GeV
/c
are determined to be
σ
pp
→
D
0
X
=
1004
±
3
±
54
μ
b
,
σ
pp
→
D
+
X
=
402
±
2
±
30
μ
b
,
σ
pp
→
D
s
+
X
=
170
±
4
±
16
μ
b
,
σ
pp
→
D
∗
+
X
=
421
±
5
±
36
μ
b
,
where the uncertainties are statistical and systematic, respectively.
The suppression of spurious events in the region of interest for neutrinoless double beta decay will play a major role in next generation experiments. The background of detectors based on the ...technology of cryogenic calorimeters is expected to be dominated by
α
particles, that could be disentangled from double beta decay signals by exploiting the difference in the emission of the scintillation light. CUPID-0, an array of enriched Zn
82
Se scintillating calorimeters, is the first large mass demonstrator of this technology. The detector started data-taking in 2017 at the Laboratori Nazionali del Gran Sasso with the aim of proving that dual read-out of light and heat allows for an efficient suppression of the
α
background. In this paper we describe the software tools we developed for the analysis of scintillating calorimeters and we demonstrate that this technology allows to reach an unprecedented background for cryogenic calorimeters.
The R&D activity performed during the last years proved the potential of ZnSe scintillating bolometers to the search for neutrino-less double beta decay, motivating the realization of the first ...large-mass experiment based on this technology: CUPID-0. The isotopic enrichment in Se-82, the (ZnSe)-Se-82 crystals growth, as well as the light detectors production have been accomplished, and the experiment is now in construction at Laboratori Nazionali del Gran Sasso (Italy). In this paper we present the results obtained testing the first three (ZnSe)-Se-82 crystals operated as scintillating bolometers, and we prove that their performance in terms of energy resolution, background rejection capability and intrinsic radiopurity complies with the requirements of CUPID-0.
The CUPID-0 experiment searches for double beta decay using cryogenic calorimeters with double (heat and light) read-out. The detector, consisting of 24 ZnSe crystals 95 Formula omitted enriched in ...Formula omittedSe and two natural ZnSe crystals, started data-taking in 2017 at Laboratori Nazionali del Gran Sasso. We present the search for the neutrino-less double beta decay of Formula omittedSe into the 0 Formula omitted, 2 Formula omitted and 2 Formula omitted excited states of Formula omittedKr with an exposure of 5.74 kg Formula omittedyr (2.24 Formula omitted10 Formula omitted emitters Formula omittedyr). We found no evidence of the decays and set the most stringent limits on the widths of these processes: Formula omitted( Formula omittedSe Formula omittedKr Formula omitted)8.55 Formula omitted10 Formula omitted yr Formula omitted, Formula omitted ( Formula omitted Se Formula omitted Kr Formula omitted) Formula omitted yr Formula omitted, Formula omitted( Formula omittedSe Formula omittedKr Formula omitted)8.25 Formula omitted10 Formula omitted yr Formula omitted (90 Formula omitted credible interval).