135 research outputs found
Solving the problem of anomalous J/ suppression by the MPD experiment on the NICA collider
The meassurements of charmonium states production via their decay on lepton pairs by the MPD experiment on the NICA collider at the energies = 4-11 GeV per nucleon could provide important data for solving the problem of anomalous J/ suppression first observed in central Pb-Pb collisions by the NA50 Collaboration at 158 GeV/nucleon. The anomalous J/ suppression could be due to the formation of the QGP in the central heavy-ion collisions. However, this effect could be also interpreted as the result of the comover interactions in nuclear matter. The recent experiments at the SPS, at the RHIC, and the LHC reviewed in this article indicate a more complicated picture of the J/ production including the recombination, medium effects, parton shadowing, and the coherent energy loss mechanism. A more simple production mechanism could be expected at low colliding energies. However, no data were obtained at energies below GeV for heavy-ion collisions. After the short review of the whole set of the data of charmonium states observation the estimation of the production rate for the MPD/NICA is made
First measurement of Ωc0 production in pp collisions at s=13 TeV
The inclusive production of the charm–strange baryon 0 c is measured for the first time via its hadronic √ decay into −π+ at midrapidity (|y| <0.5) in proton–proton (pp) collisions at the centre-of-mass energy s =13 TeV with the ALICE detector at the LHC. The transverse momentum (pT) differential cross section multiplied by the branching ratio is presented in the interval 2 < pT < 12 GeV/c. The pT dependence of the 0 c-baryon production relative to the prompt D0-meson and to the prompt 0 c-baryon production is compared to various models that take different hadronisation mechanisms into consideration. In the measured pT interval, the ratio of the pT-integrated cross sections of 0 c and prompt + c baryons multiplied by the −π+ branching ratio is found to be larger by a factor of about 20 with a significance of about 4σ when compared to e+e− collisions
Elliptic flow of charged particles at midrapidity relative to the spectator plane in Pb–Pb and Xe–Xe collisions
Measurements of the elliptic flow coefficient relative to the collision plane defined by the spectator neutrons v2{ SP} in collisions of Pb ions at center-of-mass energy per nucleon–nucleon pair √ 2.76 TeV and Xe ions at √ sNN = sNN =5.44 TeV are reported. The results are presented for charged particles produced at midrapidity as a function of centrality and transverse momentum for the 5–70% and 0.2–6 GeV/c ranges, respectively. The ratio between v2{ SP} and the elliptic flow coefficient relative to the participant plane v2{4}, estimated using four-particle correlations, deviates by up to 20% from unity depending on centrality. This observation differs strongly from the magnitude of the corresponding eccentricity ratios predicted by the TRENTo and the elliptic power models of initial state fluctuations that are tuned to describe the participant plane anisotropies. The differences can be interpreted as a decorrelation of the neutron spectator plane and the reaction plane because of fragmentation of the remnants from the colliding nuclei, which points to an incompleteness of current models describing the initial state fluctuations. A significant transverse momentum dependence of the ratio v2{ SP}/v2{4} is observed in all but the most central collisions, which may help to understand whether momentum anisotropies at low and intermediate transverse momentum have a common origin in initial state f luctuations. The ratios of v2{ SP} and v2{4} to the corresponding initial state eccentricities for Xe–Xe and Pb–Pb collisions at similar initial entropy density show a difference of (7.0 ±0.9)%with an additional variation of +1.8% when including RHIC data in the TRENTo parameter extraction. These observations provide new experimental constraints for viscous effects in the hydrodynamic modeling of the expanding quark–gluon plasma produced in heavy-ion collisions at the LHC
High diffusion length silicon germanium alloy thin films deposited by pulsed rf PECVD method
International audienc
Structural and optoelectronic properties of SiGe alloy thin films deposited by pulsed RF plasma CVD
International audienc
Not Available
Not AvailableAMF have the potential to ameliorate salt stress and improve plant growth. AMF-mediated
amelioration is attributed due to accumulation of different solutes and
higher uptake of water and nutrients under salinity conditions. AMF symbiosis also
regulates various plant physiological and biochemical processes such as water
potential, ionic balance, stomata conductance, maintenance of photosynthesis,
reduction of oxidative damage through antioxidant production and hormone-mediated
signal transduction. However, the ultimate mechanisms that allow AMF
plants a higher tolerance to salinity are still in infancy. Molecular bases of regulation
of ionic homeostatis, cation to proton antiporter and cyclic nucleotide-gated channels
under AMF symbiosis are largely unknown. Thus investigation on these aspects
on arbuscular mycorrhizal symbiosis under salinity is a promising field that should
shed further light on new mechanisms involved in the enhanced tolerance of AM
plants to salt stress. Further, transcriptomic analysis of some AMF is a promising
tool that could provide new data regarding fungal genes that may also participate in
the response of AMF symbiosis to salinity stress.Not Availabl
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