Neutral kaon pairs produced in ϕ decays in anti-symmetric entangled state can be exploited to search for violation of CPT symmetry and Lorentz invariance. We present an analysis of the CP-violating ...process ϕ→KSKL→π+π−π+π− based on 1.7 fb−1 of data collected by the KLOE experiment at the Frascati ϕ-factory DAΦNE. The data are used to perform a measurement of the CPT-violating parameters Δaμ for neutral kaons in the context of the Standard Model Extension framework. The parameters measured in the reference frame of the fixed stars are:Δa0=(−6.0±7.7stat±3.1syst)×10−18 GeV,ΔaX=(0.9±1.5stat±0.6syst)×10−18 GeV,ΔaY=(−2.0±1.5stat±0.5syst)×10−18 GeV,ΔaZ=(3.1±1.7stat±0.5syst)×10−18 GeV. These are presently the most precise measurements in the quark sector of the Standard Model Extension.
We have measured the cross section σ(e+e−→π+π−γ(γ)) at DAΦNE, the Frascati ϕ-factory, using events with initial state radiation photons emitted at small angle and inclusive of final state radiation. ...We present the analysis of a new data set corresponding to an integrated luminosity of 240 pb−1. We have achieved a reduced systematic uncertainty with respect to previously published KLOE results. From the cross section we obtain the pion form factor and the contribution to the muon magnetic anomaly from two-pion states in the mass range 0.592<Mππ<0.975 GeV. For the latter we find Δππaμ=(387.2±0.5stat±2.4exp±2.3th)×10−10.
The existence of a light dark force mediator has been tested with the KLOE detector at DA Phi NE. This particle, called U. is searched for using the decay chain phi -> eta U, eta -> ...pi(+)pi(-)pi(0), U -> e(+)e(-). No evidence is found in 1.5 fb(-1) of data. The resulting exclusion plot covers the mass range 5 < M-U < 470 MeV, setting an upper limit on the ratio between the U boson coupling constant and the One structure constant, alpha'/alpha, of <= 2 x 10(-5) at 90% C.L. for 50 < M-U < 420 MeV.
The nSYNC chip is a radiation tolerant custom ASIC, developed in UMC 130 nm technology, and the main component of the new readout electronics for the LHCb Muon Detector Upgrade. The nSYNC has been ...developed in order to implement all the required functionalities for the readout upgrade in terms of timing alignment and measurements, and equipped also with control and monitoring features. The internal architecture of the chip, the data flow and test results on different nSYNC functionalities are presented.
A
bstract
Using 1.63 fb
−1
of integrated luminosity collected by the KLOE experiment about 7 × 10
4
K
S
→
π
±
e
∓
ν
decays have been reconstructed. The measured value of the charge asymmetry for this ...decay is
A
S
= (−4.9 ± 5.7
stat
± 2.6
syst
) × 10
−3
, which is almost twice more precise than the previous KLOE result. The combination of these two measurements gives
A
S
= (−3.8 ± 5.0
stat
± 2.6
syst
) × 10
−3
and, together with the asymmetry of the
K
L
semileptonic decay, provides significant tests of the
CPT
symmetry. The obtained results are in agreement with
CPT
invariance.
A
bstract
The quantum interference between the decays of entangled neutral kaons is studied in the process
ϕ
→ K
S
K
L
→
π
+
π
−
π
+
π
−
, which exhibits the characteristic Einstein-Podolsky-Rosen ...correlations that prevent both kaons to decay into
π
+
π
−
at the same time. This constitutes a very powerful tool for testing at the utmost precision the quantum coherence of the entangled kaon pair state, and to search for tiny decoherence and
$$ \mathcal{CPT} $$
CPT
violation effects, which may be justified in a quantum gravity framework.
The analysed data sample was collected with the KLOE detector at DAΦNE, the Frascati
ϕ
-factory, and corresponds to an integrated luminosity of about 1.7 fb
−
1
, i.e. to about 1
.
7 × 10
9
ϕ
→ K
S
K
L
decays produced. From the fit of the observed ∆
t
distribution, being ∆
t
the difference of the kaon decay times, the decoherence and
$$ \mathcal{CPT} $$
CPT
violation parameters of various phenomenological models are measured with a largely improved accuracy with respect to previous analyses.
The results are consistent with no deviation from quantum mechanics and
$$ \mathcal{CPT} $$
CPT
symmetry, while for some parameters the precision reaches the interesting level at which — in the most optimistic scenarios — quantum gravity effects might show up. They provide the most stringent limits up to date on the considered models.
A
bstract
Based on an integrated luminosity of 1.61 fb
−
1
e
+
e
−
collision data collected with the KLOE detector at DAΦNE, the Frascati
ϕ
-factory, a search for the
P
- and
CP
-violating decay
η → ...π
+
π
−
has been performed. Radiative
ϕ → ηγ
decay is exploited to access the
η
mesons. No signal is observed in the
π
+
π
−
invariant mass spectrum, and the upper limit on the branching fraction at 90% confidence level is determined to be ℬ(
η → π
+
π
−
)
<
4
.
9
×
10
−
6
, which is approximately three times smaller than the previous KLOE result. From the combination of these two measurements we get ℬ(
η → π
+
π
−
)
<
4
.
4
×
10
−
6
at 90% confidence level.
Individuals suffering from dementia are affected by a progressive and significant global deterioration and, consequently, might require longer assistance in the advanced stage of the illness. The ...illness is a great burden on the person who takes care of a patient, namely, the caregiver. This study aims to analyze the presence and relationship of specific sociodemographic variables, subjective burden, and depressive symptoms among caregivers of patients with dementia.
The participants of this study were caregivers at a health care unit for the elderly in southern Italy. An evaluation of the burden of patients with dementia on caregivers was carried out using the Caregiver Burden Inventory (CBI) and depressive symptoms using the Self-Rating Depression Scale (SDS).
A total of 150 caregivers completed the study. In all, 83 (55%) caregivers showed a total CBI score ≥36, of whom 70% showed pathological depression scores in SDS. According to SDS, 28 (19%) caregivers showed a total CBI score from 24 to 36, of whom 32% were depressed. Depression was present in 5% of the caregivers whose CBI score was <24. Hence, an association between burden and depression was evident (χ(2)=47.446, P<0.001). A multiple linear regression analysis showed that depression (adjusted R(2)=0.622, F=50.123, P<0.001) was associated with higher physical (β=0.666, P=0.001) and developmental (β=0.712, P<0.001) burdens, lower socioeconomic status (β=-4.282; P=0.002), higher level of urbanicity (β=3.070; P=0.012), and advanced age (β=2.132; P=0.08).
Our study confirms the presence of depressive symptoms in a large number of caregivers with high burden. Nevertheless, this study demonstrates that depressive symptoms are mainly associated with sociodemographic variables and, to a lesser degree, physical and developmental burdens.