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Observation of seasonal variation of atmospheric multiple-muon events in the NOvA Near Detector
Using two years of data from the NOvA Near Detector at Fermilab, we report a seasonal variation of cosmic ray induced multiple-muon (Nμ≥2) event rates which has an opposite phase to the seasonal variation in the atmospheric temperature. The strength of the seasonal multiple-muon variation is shown to increase as a function of the muon multiplicity. However, no significant dependence of the strength of the seasonal variation of the multiple-muon variation is seen as a function of the muon zenith angle, or the spatial or angular separation between the correlated muons
The dependence of dijet production on photon virtuality in ep collisions at HERA
The dependence of dijet production on the virtuality of the exchanged photon,
Q^2, has been studied by measuring dijet cross sections in the range 0 < Q^2 <
2000 GeV^2 with the ZEUS detector at HERA using an integrated luminosity of
38.6 pb^-1.
Dijet cross sections were measured for jets with transverse energy E_T^jet >
7.5 and 6.5 GeV and pseudorapidities in the photon-proton centre-of-mass frame
in the range -3 < eta^jet <0. The variable xg^obs, a measure of the photon
momentum entering the hard process, was used to enhance the sensitivity of the
measurement to the photon structure. The Q^2 dependence of the ratio of low- to
high-xg^obs events was measured.
Next-to-leading-order QCD predictions were found to generally underestimate
the low-xg^obs contribution relative to that at high xg^obs. Monte Carlo models
based on leading-logarithmic parton-showers, using a partonic structure for the
photon which falls smoothly with increasing Q^2, provide a qualitative
description of the data.Comment: 35 pages, 6 eps figures, submitted to Eur.Phys.J.
Beauty photoproduction measured using decays into muons in dijet events in ep collisions at =318 GeV
The photoproduction of beauty quarks in events with two jets and a muon has
been measured with the ZEUS detector at HERA using an integrated luminosity of
110 pb. The fraction of jets containing b quarks was extracted from the
transverse momentum distribution of the muon relative to the closest jet.
Differential cross sections for beauty production as a function of the
transverse momentum and pseudorapidity of the muon, of the associated jet and
of , the fraction of the photon's momentum participating in
the hard process, are compared with MC models and QCD predictions made at
next-to-leading order. The latter give a good description of the data.Comment: 32 pages, 6 tables, 7 figures Table 6 and Figure 7 revised September
200
Search for a narrow charmed baryonic state decaying to D^*+/- p^-/+ in ep collisions at HERA
A resonance search has been made in the D^*+/- p^-/+ invariant-mass spectrum
with the ZEUS detector at HERA using an integrated luminosity of 126 pb^-1. The
decay channels D^*+ -> D^0 pi^+_s -> (K^- pi^+) pi^+_s and D^*+ -> D^0 pi^+_s
-> (K^- pi^+ pi^+ pi^-) pi^+_s (and the corresponding antiparticle decays) were
used to identify D^*+/- mesons. No resonance structure was observed in the
D^*+/- p^-/+ mass spectrum from more than 60000 reconstructed D^*+/- mesons.
The results are not compatible with a report of the H1 Collaboration of a
charmed pentaquark, Theta^0_c.Comment: 22 pages, 7 figures, 1 table; minor text revisions; 2 references
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Angular and Current-Target Correlations in Deep Inelastic Scattering at HERA
Correlations between charged particles in deep inelastic ep scattering have
been studied in the Breit frame with the ZEUS detector at HERA using an
integrated luminosity of 6.4 pb-1. Short-range correlations are analysed in
terms of the angular separation between current-region particles within a cone
centred around the virtual photon axis. Long-range correlations between the
current and target regions have also been measured. The data support
predictions for the scaling behaviour of the angular correlations at high Q2
and for anti-correlations between the current and target regions over a large
range in Q2 and in the Bjorken scaling variable x. Analytic QCD calculations
and Monte Carlo models correctly describe the trends of the data at high Q2,
but show quantitative discrepancies. The data show differences between the
correlations in deep inelastic scattering and e+e- annihilation.Comment: 26 pages including 10 figures (submitted to Eur. J. Phys. C
Plastisol Foaming Process. Decomposition of the Foaming Agent, Polymer Behavior in the Corresponding Temperature Range and Resulting Foam Properties
The decomposition of azodicarbonamide, used as foaming agent in PVC - plasticizer (1/1) plastisols was studied by DSC. Nineteen different plasticizers, all belonging to the ester family, two being polymeric (polyadipates), were compared. The temperature of maximum decomposition rate (in anisothermal regime at 5 K min-1 scanning rate), ranges between 434 and 452 K. The heat of decomposition ranges between 8.7 and 12.5 J g -1. Some trends of variation of these parameters appear significant and are discussed in terms of solvent (matrix) and viscosity effects on the decomposition reactions. The shear modulus at 1 Hz frequency was determined at the temperature of maximum rate of foaming agent decomposition, and differs significantly from a sample to another. The foam density was determined at ambient temperature and the volume fraction of bubbles was used as criterion to judge the efficiency of the foaming process. The results reveal the existence of an optimal shear modulus of the order of 2 kPa that corresponds roughly to plasticizer molar masses of the order of 450 ± 50 g mol-1. Heavier plasticizers, especially polymeric ones are too difficult to deform. Lighter plasticizers such as diethyl phthalate (DEP) deform too easily and presumably facilitate bubble collapse
Will emergency and surgical patients participate in and complete alcohol interventions? A systematic review
<p>Abstract</p> <p>Background</p> <p>In the everyday surgical life, staff may experience that patients with Alcohol Use Disorders (AUDs) seem reluctant to participate in alcohol intervention programs. The objective was therefore to assess acceptance of screening and intervention as well as adherence to the intervention program among emergency department (ED) and surgical patients with AUDs.</p> <p>Methods</p> <p>A systematic literature search was followed by extraction of acceptance and adherence rates in ED and surgical patients. Numbers needed to screen (NNS) were calculated. Subgroup analyses were carried out based on different study characteristics.</p> <p>Results</p> <p>The literature search revealed 33 relevant studies. Of these, 31 were randomized trials, 28 were conducted in EDs and 31 evaluated the effect of brief alcohol intervention. Follow-up was mainly conducted after six and/or twelve months.</p> <p>Four in five ED patients accepted alcohol screening and two in three accepted participation in intervention. In surgical patients, two in three accepted screening and the intervention acceptance rate was almost 100%. The adherence rate was above 60% for up to twelve months in both ED and surgical patients. The NNS to identify one eligible AUD patient and to get one eligible patient to accept participation in alcohol intervention varied from a few up to 70 patients.</p> <p>The rates did not differ between randomized and non-randomized trials, brief and intensive interventions or validated and self-reported alcohol consumption. Adherence rates were not affected by patients' group allocation and type of follow-up.</p> <p>Conclusions</p> <p>Most emergency and surgical patients with AUD accept participation in alcohol screening and interventions and complete the intervention program.</p
First measurement of neutrino oscillation parameters using neutrinos and antineutrinos by NOvA
The NOvA experiment has seen a 4.4σ signal of ν̄e appearance in a 2 GeV ν̄μ beam at a distance of 810 km. Using 12.33×1020 protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν̄μ→ν̄e candidates with a background of 10.3 and 102 ν̄μ→ν̄μ candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm322|=2.48-0.06+0.11×10-3 eV2/c4 and sin2θ23 in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δCP=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ23 values in the upper octant by 1.6σ
First measurement of neutrino oscillation parameters using neutrinos and antineutrinos by NOvA
The NOvA experiment has seen a
4.4
σ
signal of
¯
ν
e
appearance in a 2 GeV
¯
ν
μ
beam at a distance of 810 km. Using
12.33
×
10
20
protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27
¯
ν
μ
→
¯
ν
e
candidates with a background of 10.3 and 102
¯
ν
μ
→
¯
ν
μ
candidates. This new antineutrino data are combined with neutrino data to measure the parameters
|
Δ
m
2
32
|
=
2.4
8
+
0.11
−
0.06
×
10
−
3
eV
2
/
c
4
and
sin
2
θ
23
in the ranges from (0.53–0.60) and (0.45–0.48) in the normal neutrino mass hierarchy. The data exclude most values near
δ
C
P
=
π
/
2
for the inverted mass hierarchy by more than
3
σ
and favor the normal neutrino mass hierarchy by
1.9
σ
and
θ
23
values in the upper octant by
1.6
σ
- …