Phys. Rev. Lett. 118, 222002 (2017) We report the first longitudinal/transverse separation of the deeply virtual
exclusive $\pi^0$ electroproduction cross section off the neutron and coherent
...deuteron. The corresponding four structure functions $d\sigma_L/dt$,
$d\sigma_T/dt$, $d\sigma_{LT}/dt$ and $d\sigma_{TT}/dt$ are extracted as a
function of the momentum transfer to the recoil system at $Q^2$=1.75 GeV$^2$
and $x_B$=0.36. The $ed \to ed\pi^0$ cross sections are found compatible with
the small values expected from theoretical models. The $en \to en\pi^0$ cross
sections show a dominance from the response to transversely polarized photons,
and are in good agreement with calculations based on the transversity GPDs of
the nucleon. By combining these results with previous measurements of $\pi^0$
electroproduction off the proton, we present a flavor decomposition of the $u$
and $d$ quark contributions to the cross section.
Phys. Rev. Lett. 117, 262001 (2016) We present deeply virtual $\pi^0$ electroproduction cross-section
measurements at $x_B$=0.36 and three different $Q^2$--values ranging from 1.5
to 2 GeV$^2$, ...obtained from experiment E07-007 that ran in the Hall A at
Jefferson Lab. The Rosenbluth technique was used to separate the longitudinal
and transverse responses. Results demonstrate that the cross section is
dominated by its transverse component, and thus is far from the asymptotic
limit predicted by perturbative Quantum Chromodynamics. An indication of a
non-zero longitudinal contribution is provided by the interference term
$\sigma_{LT}$ also measured. Results are compared with several models based on
the leading twist approach of Generalized Parton Distributions (GPDs). In
particular, a fair agreement is obtained with models where the scattering
amplitude is described by a convolution of chiral-odd (transversity) GPDs of
the nucleon with the twist-3 pion distribution amplitude. Therefore, neutral
pion electroproduction may offer the exciting possibility of accessing
transversity GPDs through experiment.
We report on new p$(e,e^\prime p)\pi^\circ$ measurements at the
$\Delta^{+}(1232)$ resonance at the low momentum transfer region. The mesonic
cloud dynamics is predicted to be dominant and rapidly ...changing in this
kinematic region offering a test bed for chiral effective field theory
calculations. The new data explore the low $Q^2$ dependence of the resonant
quadrupole amplitudes while extending the measurements of the Coulomb
quadrupole amplitude to the lowest momentum transfer ever reached. The results
disagree with predictions of constituent quark models and are in reasonable
agreement with dynamical calculations that include pion cloud effects, chiral
effective field theory and lattice calculations. The reported measurements
suggest that improvement is required to the theoretical calculations and
provide valuable input that will allow their refinements.
We report the first longitudinal/transverse separation of the deeply virtual exclusive \(\pi^0\) electroproduction cross section off the neutron and coherent deuteron. The corresponding four ...structure functions \(d\sigma_L/dt\), \(d\sigma_T/dt\), \(d\sigma_{LT}/dt\) and \(d\sigma_{TT}/dt\) are extracted as a function of the momentum transfer to the recoil system at \(Q^2\)=1.75 GeV\(^2\) and \(x_B\)=0.36. The \(ed \to ed\pi^0\) cross sections are found compatible with the small values expected from theoretical models. The \(en \to en\pi^0\) cross sections show a dominance from the response to transversely polarized photons, and are in good agreement with calculations based on the transversity GPDs of the nucleon. By combining these results with previous measurements of \(\pi^0\) electroproduction off the proton, we present a flavor decomposition of the \(u\) and \(d\) quark contributions to the cross section.
We present deeply virtual \(\pi^0\) electroproduction cross-section measurements at \(x_B\)=0.36 and three different \(Q^2\)--values ranging from 1.5 to 2 GeV\(^2\), obtained from experiment E07-007 ...that ran in the Hall A at Jefferson Lab. The Rosenbluth technique was used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component, and thus is far from the asymptotic limit predicted by perturbative Quantum Chromodynamics. An indication of a non-zero longitudinal contribution is provided by the interference term \(\sigma_{LT}\) also measured. Results are compared with several models based on the leading twist approach of Generalized Parton Distributions (GPDs). In particular, a fair agreement is obtained with models where the scattering amplitude is described by a convolution of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. Therefore, neutral pion electroproduction may offer the exciting possibility of accessing transversity GPDs through experiment.
We report on new p\((e,e^\prime p)\pi^\circ\) measurements at the \(\Delta^{+}(1232)\) resonance at the low momentum transfer region. The mesonic cloud dynamics is predicted to be dominant and ...rapidly changing in this kinematic region offering a test bed for chiral effective field theory calculations. The new data explore the low \(Q^2\) dependence of the resonant quadrupole amplitudes while extending the measurements of the Coulomb quadrupole amplitude to the lowest momentum transfer ever reached. The results disagree with predictions of constituent quark models and are in reasonable agreement with dynamical calculations that include pion cloud effects, chiral effective field theory and lattice calculations. The reported measurements suggest that improvement is required to the theoretical calculations and provide valuable input that will allow their refinements.
Eight new and 10 known compounds were isolated from an organic extract of the bulbs of Bellevalia eigii as part of a search for anticancer leads from native plants of Jordan. Of these, the series of ...16 homoisoflavonoids (1–16) comprise the seven new analogues 7-O-methyl-3′-hydroxy-3,9-dihydropunctatin (3), 6-hydroxy-7-O-methyl-3,9-dihydropunctatin (6), 7,4′-di-O-methyl-3′-hydroxy-3,9-dihydropunctatin (9), 7-O-methylpunctatin (10), 7-O-methyl-3′-hydroxypunctatin (13), 5-hydroxy-7,8-dimethoxychroman-4-one (14), and 7-O-methyl-8-demethoxy-3-hydroxy-3,9-dihydropunctatin (15). The known ferulic acid-derived acrylamide (17) and the new methylthioacrylate bellegimycin (18) are also reported. The structures were elucidated using a set of spectroscopic and spectrometric techniques; the absolute configurations of compounds 1–9, 15, and 16 were determined using ECD spectroscopy, while a modified Mosher’s ester method was used for compound 18. Optical rotation data for the known compounds 1, 2, and 8 are reported here for the first time. The cytotoxic activities of all compounds were evaluated using the MDA-MB-435 (melanoma) and HT-29 (colon) cancer cell lines. Compounds 4 and 9 were the most potent on the latter cell line, with IC50 values of 1.0 and 1.1 μM, respectively. Compounds 1–18 were assessed for antimicrobial activity using a collection of bacteria and fungi; compounds 4 and 12 showed promising activity against the bacterium Mycobacterium smegmatis with MIC values of 17 and 24 μg/mL, respectively.
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IJS, KILJ, NUK, PNG, UL, UM
Hybrid material of poly-methyle-methacrylate (PMMA)-benzyl-dimethyl-ketal-azo dye methyl red (MR) thin film composites doped by various concentrations of ZnO NPs have been dip coated on glass ...substrates. The existence of azo dye (MR) in the composite was intentional to give the solution the desired pH level and to induce the
cis ↔ trans
cycles through illumination
↔
thermal relaxation. The optical and structural properties of the as-prepared thin films are investigated in relevance to ZnO NPs contents and the period of UV light illumination (short- and long-wavelength UV light). We found that the PMMA-BDK-MR doped by 1% ZnO NPs could be successfully used in optical data storage by implementing this composite in the WRITE/READ/ERASE cycle repeatedly. Specifically, it was found that the absorption band of the PMMA-BDK-MR doped by 1% ZnO NPs thin film lies between 350 and 600 nm upon illumination with 366 nm UV light for 10 s. Thermogravimetric analysis (TGA) was used to investigate the thermal stability of PMMA-BDK-MR/ZnO NPs. The TGA results are presented and interpreted. Furthermore, we investigated annealed poly-methyle-methacrylate-benzyl-dimethyl-ketal-methyl-red (PMMA-BDK-MR) doped by 1% ZnO NPs thin films. The
trans
–
cis
cycle has been repeated sequentially to confirm the hysteresis behavior for possible data READ/WRITE or ERASE memory applications.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This White Paper aims at highlighting the important benefits in the science reach of the EIC. High luminosity operation is generally desirable, as it enables producing and harvesting scientific ...results in a shorter time period. It becomes crucial for programs that would require many months or even years of operation at lower luminosity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The development of mobile edge computing (MEC) is expected to offer better performance in mobile communications than the current cloud computing architecture. MEC involves offering the closest access ...to the data source or physical mobile network environment. The network services are able to respond faster, thus satisfying the demands of the mobile network industry when deploying various potential business applications in real-time. Since the harvested mobile data are transferred to the edge server to make calculations, data transfers and faults in the mobile network can be swiftly pinpointed and removed accurately. Nevertheless, there are still problems in the practical application of the systems, specifically in reducing delays and lessening energy consumption. Because of non-orthogonal multiple access (NOMA) superior spectrum efficiencies, it is best to combine NOMA with MEC for simultaneous support of multiple access for end users, thus reducing transmission latencies and lowering energy consumption. Combining MEC and NOMA would offer many advantages, including superior energy savings, reductions in latency, massive connectivity, and the potential of combining with additional transmission technologies, such as millimetre-wave (mmWave) and M-MIMO. In this paper, designing wireless resource allocation is crucial for an economically viable low-latency wireless network, which can be realised using the Karush–Kuhn–Tucker (KKT) approach to obtain the optimal solution for partial and full offloading network traffic scenarios to minimize the total latency of the MEC network. The convergence and performance for orthogonal multiple access (OMA), pure-NOMA (P-NOMA), and hybrid-NOMA (H-NOMA) are also compared under different network traffic offloading scenarios. The significant results from this study showed the convergence of the optimal resource allocation in the case of full and partial offloading. The results demonstrated that the P-NOMA reduces the total offloading delay by about 11%.
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