40 research outputs found
Directed flow from C-odd gluon correlations at small
It is shown that odd harmonic azimuthal correlations, including the directed
flow , in forward two-particle production in peripheral proton-nucleus
() collisions can arise simply from the radial nuclear profile of a large
nucleus. This requires consideration of the C-odd part of the gluonic
generalized transverse momentum dependent (GTMD) correlator of nucleons in the
nucleus. The gluonic GTMD correlator is the Fourier transform of an off-forward
hadronic matrix element containing gluonic field strength tensors that are
connected by gauge links. It is parametrized in terms of various gluon GTMD
distribution functions (GTMDs). We show (in a gauge invariant way) that for the
relevant dipole-type gauge link structure in the small- limit the GTMD
correlator reduces to a generalized Wilson loop correlator. The Wilson loop
correlator is parametrized in terms of a single function, implying that in the
region of small there is only one independent dipole-type GTMD, which can
have a C-odd part. We show that the odderon Wigner distribution, which is
related to this C-odd dipole GTMD by a Fourier transform, generates odd
harmonics in the two-particle azimuthal correlations in peripheral
collisions. We calculate the first odd harmonic for forward production
within the color glass condensate framework in the limit of a large number of
colors. We find that nonzero odd harmonics are present without breaking the
rotational symmetry of the nucleus, arising just from its inhomogeneity in the
radial direction. Using a CGC model with a cubic action, we illustrate that
percent level can arise from this C-odd mechanism. In contrast, we show
that only even harmonics arise in diffractive dijet production in
ultra-peripheral collisions where this gluon dipole GTMD also appears.Comment: 23 pages, 3 figures. v2: References added; Added plot for A=63 in
Fig.3 and a discussion on the A dependence. Version accepted for publication
in JHE
Usage of Biologics on Tomatoes and Peppers
In fruit growing, nowadays a lot of chemical products are used
(insecticide, fungicide etc.) in order to protect the plants. However, lately the markets
are in need of gardening products which are not treated with pesticide but protected with
biologics. In gardening, biological fight against the insects and the diseases is not much
maintained because the shares are lower and the gardening products are on a great
demand and are very profitable. Due to the great profit of the gardening products, less
attention is paid to the biological fight for protection. However, the great environmental
pollution evokes great interest in consuming healthy gardening products.
Due to the mentioned reasons, lately, fruit producers show interest for usage of
biologics to protect the gardening products from some insects and diseases. There
appear to be many biologics but the producers of gardening products are not well
informed because the interest of usage of biologics is not high. By all means, the market
provides verified biologics which show good production results. The great interest in
usage of biologics to protect the gardening products from diseases and insects increases,
whereas the interest of research institutions to discover better biologics is getting bigger
Subclinical reactivation of varicella zoster virus after covid-19 as a possible cause of stroke in young patient
Previous studies have observed an association between Varicella Zoster Virus (VZV) infection and stroke. Here we discuss possible causes of Herpes Zoster (HZ) due to COVID-19. Reactivation of VZV caused by decline of cellular immune response has been noted during the convalescent period or after recovery from COVID-19. Whether s troke can be a late sequel of a COVID-19 due to different inflammatory and coagulation mechanisms is currently uncertain. We present the case of a young patient with acute ischemic stroke, two months after mild COVID19 infection associated with subclinical reactivation of VZV infection and discuss possible causes of stroke.
Diffusio
Transverse Momentum Dependent (TMD) Parton Distribution Functions: Status and Prospects
We review transverse momentum dependent (TMD) parton distribution functions, their application to topical issues in high-energy physics phenomenology, and their theoretical connections with QCD resummation, evolution and factorization theorems. We illustrate the use of TMDs via examples of multi-scale problems in hadronic collisions. These include transverse momentum qT spectra of Higgs and vector bosons for low qT, and azimuthal correlations in the production of multiple jets associated with heavy bosons at large jet masses. We discuss computational tools for TMDs, and present the application of a new tool, TMDLIB, to parton density fits and parameterizations
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A kinematic examination of dual-route processing for action imitation
The dual-route model of imitation suggests that meaningful and meaningless actions are processed through either an indirect or direct route, respectively. Evidence indicates that the direct route is more cognitively demanding, since it relies on mapping visuospatial properties of the observed action on to a performed one. These cognitive demands might negatively influence reaction time and accuracy for actions performed following a meaningless action under time constraints. However, how meaningful and meaningless action imitation processing is reflected in movement kinematics is not yet clear. We wanted to confirm whether
meaningless action performance incurs a reaction time cost, whether the cost is reflected in kinematics, and, more generally, to examine kinematic markers of emblematic meaningful and meaningless action imitation. We examined participants’ reaction time and wrist movements when they imitated emblematic meaningful or matched meaningless gestures in either blocks of the same action type, or mixed blocks. Meaningless actions were associated with a greater correction period at the end of the movement, possibly reflecting a strategy designed to ensure accurate completion for less familiar actions under time constraints. Furthermore, in mixed blocks, trials following meaningless actions had a significantly increased reaction time, supporting previous claims that route selection for action imitation may be stimulus-driven. However, there was only convincing evidence for this effect with an interval of ~2948ms, but not ~3573ms or ~2553ms, between movements. Future work motion-tracking the entire hand to assess imitation accuracy, and more closely examining the influence of duration between movements, may help to explain these effects