The results obtained with the total exposure of 1.04 ton × yr collected by DAMA/LIBRA–phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles ...(i.e. adding a further 0.17 ton × yr exposure) are presented. The DAMA/LIBRA–phase1 data give evidence for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radio-pure NaI(Tl) target, at 7.5
σ
C.L. Including also the first generation DAMA/NaI experiment (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles), the C.L. is 9.3
σ
and the modulation amplitude of the
single-hit
events in the (2–6) keV energy interval is: (0.0112±0.0012) cpd/kg/keV; the measured phase is (144±7) days and the measured period is (0.998±0.002) yr, values well in agreement with those expected for DM particles. No systematic or side reaction able to mimic the exploited DM signature has been found or suggested by anyone over more than a decade.
The highly radiopure ≃ 250 kg NaI(Tl) DAMA/LIBRA set-up is running at the Gran Sasso National Laboratory of the INFN. In this paper the first result obtained by exploiting the model independent ...annual modulation signature for Dark Matter (DM) particles is presented. It refers to an exposure of 0.53 ton×yr. The collected DAMA/LIBRA data satisfy all the many peculiarities of the DM annual modulation signature. Neither systematic effects nor side reactions able to account for the observed modulation amplitude and to contemporaneously satisfy all the several requirements of this DM signature are available. Considering the former DAMA/NaI and the present DAMA/LIBRA data all together (total exposure 0.82 ton×yr), the presence of Dark Matter particles in the galactic halo is supported, on the basis of the DM annual modulation signature, at 8.2
σ
C.L.; in particular, in the energy interval (2–6) keV, the modulation amplitude is (0.0131±0.0016) cpd/kg/keV and the phase and the period are well compatible with June 2
nd
and one year, respectively.
New results from DAMA/LIBRA Bernabei, R.; Belli, P.; Cappella, F. ...
European physical journal. C, Particles and fields,
05/2010, Letnik:
67, Številka:
1-2
Journal Article
Recenzirano
Odprti dostop
DAMA/LIBRA is running at the Gran Sasso National Laboratory of the I.N.F.N. Here the results obtained with a further exposure of 0.34 ton × yr are presented. They refer to two further annual cycles ...collected one before and one after the first DAMA/LIBRA upgrade occurred on September/October 2008. The cumulative exposure with those previously released by the former DAMA/NaI and by DAMA/LIBRA is now 1.17 ton × yr, corresponding to 13 annual cycles. The data further confirm the previous positive results obtained investigating the presence of Dark Matter (DM) particles in the galactic halo by means of the model independent Dark Matter annual modulation signature; the confidence level is now 8.9
σ
for the cumulative exposure. In particular, with the cumulative exposure the modulation amplitude of the
single-hit
events in the (2–6) keV energy interval measured in NaI(Tl) target is (0.0116±0.0013) cpd/kg/keV; the measured phase is (146±7) days and the measured period is (0.999±0.002) yr, values well in agreement with those expected for the DM particles.
The first model independent results obtained by the DAMA/LIBRA-phase2 experiment are presented. The data have been collected over 6 annual cycles corresponding to a total exposure of 1.13 t yr, ...deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. The DAMA/LIBRA-phase2 apparatus, ≃ 250 kg highly radio-pure NaI(Tl), profits from a second generation high quantum efficiency photomultipliers and of new electronics with respect to DAMA/LIBRA-phase1. The improved experimental configuration has also allowed to lower the software energy threshold. New data analysis strategies are presented. The DAMA/LIBRA-phase2 data confirm the evidence of a signal that meets all the requirements of the model independent Dark Matter (DM) annual modulation signature, at 9.5 C.L. in the energy region (1 - 6) keV. In the energy region between 2 and 6 keV, where data are also available from DAMA/NaI and DAMA/LIBRA-phase1 (exposure 1.33 t yr, collected over 14 annual cycles), the achieved C.L. for the full exposure (2.46 t yr) is 12.9 ; the modulation amplitude of the single-hit scintillation events is: (0.0103 ± ± 0.0008) cpd/kg/keV, the measured phase is (145 ± 5) d and the measured period is (0.999 ± 0.001) yr, all these values are well in agreement with those expected for DM particles. No systematics or side reaction able to mimic the exploited DM signature (i.e. to account for the whole measured modulation amplitude and to simultaneously satisfy all the requirements of the signature), has been found or suggested by anyone throughout some decades thus far.
Sclerotinia head rot (SHR), caused by the necrotrophic fungus Sclerotinia sclerotiorum, is one of the most devastating sunflower crop diseases. Despite its worldwide occurrence, the genetic ...determinants of plant resistance are still largely unknown. Here, we investigated the Sclerotinia-sunflower pathosystem by analysing temporal changes in gene expression in one susceptible and two tolerant inbred lines (IL) inoculated with the pathogen under field conditions. Differential expression analysis showed little overlapping among ILs, suggesting genotype-specific control of cell defense responses possibly related to differences in disease resistance strategies. Functional enrichment assessments yielded a similar pattern. However, all three ILs altered the expression of genes involved in the cellular redox state and cell wall remodeling, in agreement with current knowledge about the initiation of plant immune responses. Remarkably, the over-representation of long non-coding RNAs (lncRNA) was another common feature among ILs. Our findings highlight the diversity of transcriptional responses to SHR within sunflower breeding lines and provide evidence of lncRNAs playing a significant role at early stages of defense.
The channeling effect of low energy ions along the crystallographic axes and planes of NaI(Tl) crystals is discussed in the framework of corollary investigations on WIMP dark matter candidates. In ...fact, the modeling of this existing effect implies a more complex evaluation of the luminosity yield for low energy recoiling Na and I ions. In the present paper related phenomenological arguments are developed and possible implications are discussed at some extent.
This paper summarizes in a simple and intuitive way why the neutrons, the muons and the solar neutrinos cannot give any significant contribution to the DAMA annual modulation results. A number of ...these elements have already been presented in individual papers; they are recalled here together with few simple considerations which demonstrate the incorrectness of the claim reported in Davis (PRL 113:081302,
2014
).
Abstract
Sunflower Verticillium Wilt and Leaf Mottle (SVW), caused by
Verticillium dahliae
(Kleb.;
Vd
), is a soil-borne disease affecting sunflower worldwide. A single dominant locus, known as V1, ...was formerly effective in controlling North-American
Vd
races, whereas races from Argentina, Europe and an emerging race from USA overcome its resistance. This emphasizes the need for identifying broad-spectrum genetic resistance (BSR) sources. Here we characterize two sunflower mapping populations (MPs) for SVW resistance: a biparental MP and the association MP from the National Institute of Agricultural Technology (INTA), under field growing conditions. Nine field-trials (FTs) were conducted in highly infested fields in the most SVW-affected region of Argentina. Several disease descriptors (DDs), including incidence and severity, were scored across four phenological stages. Generalized linear models were fitted according to the nature of each variable, adjusting mean phenotypes for inbred lines across and within FTs. Comparison of these responses allowed the identification of novel BSR sources. Furthermore, we present the first report of SVW resistance heritability, with estimates ranging from 35 to 45% for DDs related to disease incidence and severity, respectively. This study constitutes the largest SVW resistance characterization reported to date in sunflower, identifying valuable genetic resources for BSR-breeding to cope with a pathogen of increasing importance worldwide.
The results obtained in the search for possible diurnal effect in the
single-hit
low energy data collected by DAMA/LIBRA-phase1 (total exposure 1.04 ton
×
year) deep underground at the Gran Sasso ...National Laboratory (LNGS) of the INFN are presented. At the present level of sensitivity the presence of any significant diurnal variation and of diurnal time structures in the data can be excluded for both the cases of solar and sidereal time. In particular, the diurnal modulation amplitude expected, because of the Earth diurnal motion, on the basis of the DAMA dark matter annual modulation results is below the present sensitivity.
Abstract
The existence of Dark Matter particles as a significant portion of the Universe’s total mass is suggested by theoretical reasoning at the galactic and larger scales as well as experimental ...data. This motivates the DAMA experiment’s efforts to investigate the presence of the Dark Matter particles in the galactic halo by utilizing a model-independent signature with an extremely radio-pure set-up underground. The long-standing, model-independent annual modulation effect at Gran Sasso seen by DAMA with several experimental set-ups is summarized in this paper, along with its perspectives. DAMA/LIBRA-phase2 set-up, ≃ 250 kg highly radio-pure NaI(Tl) further confirms the evidence of a signal that meets all the requirements of the model independent Dark Matter annual modulation signature at high C.L.; the combined exposure of DAMA/NaI and DAMA/LIBRA is 2.86 ton × yr over 22 independent annual cycles. The experiment is currently collecting data in the DAMA/LIBRA–phase2 empowered configuration with an even lower software energy threshold.
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