New radioactive ion beam (RIB) facilities will push further away from stability and enable the next generation of nuclear physics experiments. Of great importance to the future of RIB physics are ...scattering, transfer, and capture reaction measurements of rare, exotic, and unstable nuclei on light targets such as hydrogen and helium. These measurements require targets that are dense, highly localized, and pure. Targets must also accommodate the use of large area silicon detector arrays, high-efficiency gamma arrays, and heavy ion detector systems to efficiently measure the reaction products. To address these issues, the Jet Experiments in Nuclear Structure and Astrophysics (JENSA) Collaboration has designed, built, and characterized a supersonic gas jet target, capable of providing gas areal densities on par with commonly used solid targets within a region of a few millimeters diameter. Densities of over 5×1018atoms/cm2 of helium have been achieved, making the JENSA gas jet target the most dense helium jet achieved so far.
Since the discovery of the Higgs boson in 2012, detailed studies of its properties have been ongoing. Besides its mass, its width—related to its lifetime—is an important parameter. One way to ...determine this quantity is to measure its off-shell production, where the Higgs boson mass is far away from its nominal value, and relating it to its on-shell production, where the mass is close to the nominal value. Here we report evidence for such off-shell contributions to the production cross-section of two Z bosons with data from the CMS experiment at the CERN Large Hadron Collider. We constrain the total rate of the off-shell Higgs boson contribution beyond the Z boson pair production threshold, relative to its standard model expectation, to the interval 0.0061, 2.0 at the 95% confidence level. The scenario with no off-shell contribution is excluded at a p-value of 0.0003 (3.6 standard deviations). We measure the width of the Higgs boson as ΓH=3.2−1.7+2.4MeV, in agreement with the standard model expectation of 4.1 MeV. In addition, we set constraints on anomalous Higgs boson couplings to W and Z boson pairs.The CMS Collaboration reports evidence for off-shell Higgs boson contributions in the production of Z boson pairs, and measures the width of the Higgs boson, which is inversely related to its lifetime.
A
bstract
Jet production in lead-lead (PbPb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV is studied with the CMS detector at the LHC, using PbPb and pp ...data samples corresponding to integrated luminosities of 404
μ
b
−
1
and 27.4 pb
−
1
, respectively. Jets with different areas are reconstructed using the anti-
k
T
algorithm by varying the distance parameter
R
. The measurements are performed using jets with transverse momenta (
p
T
) greater than 200 GeV and in a pseudorapidity range of
|η| <
2. To reveal the medium modification of the jet spectra in PbPb collisions, the properly normalized ratio of spectra from PbPb and pp data is used to extract jet nuclear modification factors as functions of the PbPb collision centrality,
p
T
and, for the first time, as a function of
R
up to 1.0. For the most central collisions, a strong suppression is observed for high-
p
T
jets reconstructed with all distance parameters, implying that a significant amount of jet energy is scattered to large angles. The dependence of jet suppression on
R
is expected to be sensitive to both the jet energy loss mechanism and the medium response, and so the data are compared to several modern event generators and analytic calculations. The models considered do not fully reproduce the data.
The aims of this study were to determine whether long‐term oral administration of the opiate antagonist nalmefene is associated with any beneficial effects in patients with pruritus secondary to ...cholestatic liver disease and to assess the safety of long‐term administration of this drug to these patients. Fourteen patients with unrelieved chronic pruritus of cholestasis were studied. Scratching activity, independent of limb movements, was recorded continuously for 24‐hour periods before and during treatment with an initial ameliorating dose of nalmefene. Simultaneously, during these periods, visual analogue scores (VASs) of pruritus were recorded every 4 hours while patients were awake. The dose of nalmefene, which initially was 2 mg orally twice daily, was increased during the study, usually until a satisfactory clinical response was achieved. Five patients experienced a transient opioid withdrawal–like reaction that did not preclude continuing with nalmefene therapy. Serum biochemical indices of cholestasis did not change appreciably during treatment. Thirteen patients reported amelioration of the perception of pruritus on nalmefene. In 5 patients, exacerbations of pruritus occurred approximately 4 weeks after an initial ameliorating dose had been reached; these exacerbations were managed by increasing the dose. Baseline mean values for VAS and scratching activity were higher than corresponding means during nalmefene therapy in 13 (P =.002) and 12 (P = .013) patients, respectively. Possible tolerance to nalmefene occurred in 3 patients. Three patients experienced marked exacerbation of pruritus after nalmefene therapy was suddenly discontinued. Blood levels of nalmefene were consistent with normal pharmacokinetics of the drug. These results suggest that nalmefene may have a favorable risk‐to‐benefit ratio when it is administered orally long‐term to patients with the pruritus of cholestasis.
Catalytic chemical vapor deposition was used to grow multi-walled carbon nanotubes on a Fe:Co:CaCO
3 catalyst from acetylene. The influent and effluent gases were analyzed by gas chromatography and ...mass spectrometry at different time intervals during the nanotubes growth process in order to better understand and optimize the overall reaction. A large number of byproducts were identified and it was found that the number and the level for some of the carbon byproducts significantly increased over time. The CaCO
3 catalytic support thermally decomposed into CaO and CO
2 resulting in a mixture of two catalysts for growing the nanotubes, which were found to have outer diameters belonging to two main groups 8–35
nm and 40–60
nm, respectively.
Using small-angle neutron scattering, we investigated the behavior of a metastable vortex lattice state in MgB2 as it is driven towards equilibrium by an ac magnetic field. This shows an activated ...behavior, where the ac field amplitude and cycle count are equivalent to, respectively, an effective “temperature” and “time.” The activation barrier increases as the metastable state is suppressed, corresponding to an aging of the vortex lattice. Furthermore, we find a crossover from a partial to a complete suppression of metastable domains depending on the ac field amplitude, which may empirically be described by a single free parameter. This represents an unconventional kind of collective vortex behavior, not governed by pinning, most likely due to the nucleation and growth of equilibrium vortex lattice domains.
Summary Background Infantile spasms constitutes a severe infantile epilepsy syndrome that is difficult to treat and has a high morbidity. Hormonal therapies or vigabatrin are the most commonly used ...treatments. We aimed to assess whether combining the treatments would be more effective than hormonal therapy alone. Methods In this multicentre, open-label randomised trial, 102 hospitals (Australia three, Germany 11, New Zealand two, Switzerland three, and the UK 83) enrolled infants who had a clinical diagnosis of infantile spasms and a hypsarrhythmic (or similar) EEG no more than 7 days before enrolment. Participants were randomly assigned (1:1) by a secure website to receive hormonal therapy with vigabatrin or hormonal therapy alone. If parents consented, there was an additional randomisation (1:1) of type of hormonal therapy used (prednisolone or tetracosactide depot). Block randomisation was stratified for hormonal treatment and risk of developmental impairment. Parents and clinicians were not masked to therapy, but investigators assessing electro-clinical outcome were masked to treatment allocation. Minimum doses were prednisolone 10 mg four times a day or intramuscular tetracosactide depot 0·5 mg (40 IU) on alternate days with or without vigabatrin 100 mg/kg per day. The primary outcome was cessation of spasms, which was defined as no witnessed spasms on and between day 14 and day 42 from trial entry, as recorded by parents and carers in a seizure diary. Analysis was by intention to treat. The trial is registered with The International Standard Randomised Controlled Trial Number (ISRCTN), number 54363174, and the European Union Drug Regulating Authorities Clinical Trials (EUDRACT), number 2006-000788-27. Findings Between March 7, 2007, and May 22, 2014, 766 infants were screened and, of those, 377 were randomly assigned to hormonal therapy with vigabatrin (186) or hormonal therapy alone (191). All 377 infants were assessed for the primary outcome. Between days 14 and 42 inclusive no spasms were witnessed in 133 (72%) of 186 patients on hormonal therapy with vigabatrin compared with 108 (57%) of 191 patients on hormonal therapy alone (difference 15·0%, 95% CI 5·1–24·9, p=0·002). Serious adverse reactions necessitating hospitalisation occurred in 33 infants (16 on hormonal therapy alone and 17 on hormonal therapy with vigabatrin). The most common serious adverse reaction was infection occurring in five infants on hormonal therapy alone and four on hormonal therapy with vigabatrin. There were no deaths attributable to treatment. Interpretation Hormonal therapy with vigabatrin is significantly more effective at stopping infantile spasms than hormonal therapy alone. The 4 week period of spasm cessation required to achieve a primary clinical response to treatment suggests that the effect seen might be sustained, but this needs to be confirmed at the 18 month follow-up. Funding The Castang Foundation, Bath Unit for Research in Paediatrics, National Institute of Health Research, the Royal United Hospitals Bath NHS Foundation Trust, the BRONNER-BENDUNG Stifung/Gernsbach, and University Children's Hospital Zurich.
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