1,740 research outputs found
Probing transverse momentum dependent gluon distribution functions from hadronic quarkonium pair production
The inclusive hadronic production of ( or ) pair is
proposed to extract the transverse momentum dependent(TMD) gluon distribution
functions. We use nonrelativistic QCD(NRQCD) for the production of .
Under nonrelativistic limit TMD factorization for this process is assumed to
make a lowest order calculation. For unpolarized initial hadrons, unpolarized
and linearly polarized gluon distributions can be extracted by studying
different angular distributions.Comment: 7 pages, 3 figures, 1 tabl
The SU(3) bosons and the spin nematic state on the spin-1 bilinear-biquadratic triangular lattice
A bond-operator mean-field theory in the SU(3) bosons representation is
developed to describe the antiferro-nematic phase of the spin-1
bilinear-biquadratic model. The calculated static structure factors reveal
delicately that the antiferro-nematic state may exhibit both the ferro- and
antiferro-quadruple long-range orders, which is reminiscent of the ferrimagnets
or the canted antiferromagnets. This result may influence the spin wave theory
concerned with this phase. Possible relevance of this unconventional state to
the quasi-two-dimensional triangular material NiGa2S4 is addressed.Comment: 8pages, 6figure
A multi-wavelength observation and investigation of six infrared dark clouds
Context. Infrared dark clouds (IRDCs) are ubiquitous in the Milky Way, yet
they play a crucial role in breeding newly-formed stars.
Aims. With the aim of further understanding the dynamics, chemistry, and
evolution of IRDCs, we carried out multi-wavelength observations on a small
sample.
Methods. We performed new observations with the IRAM 30 m and CSO 10.4 m
telescopes, with tracers , HCN, , ,
DCO, SiO, and DCN toward six IRDCs G031.97+00.07, G033.69-00.01,
G034.43+00.24, G035.39-00.33, G038.95-00.47, and G053.11+00.05.
Results. We investigated 44 cores including 37 cores reported in previous
work and seven newly-identified cores. Toward the dense cores, we detected 6
DCO, and 5 DCN lines. Using pixel-by-pixel spectral energy distribution
(SED) fits of the 70 to 500 m, we obtained dust
temperature and column density distributions of the IRDCs. We found that emission has a strong correlation with the dust temperature and column
density distributions, while showed the weakest correlation. It
is suggested that is indeed a good tracer in very dense
conditions, but is an unreliable one, as it has a relatively
low critical density and is vulnerable to freezing-out onto the surface of cold
dust grains. The dynamics within IRDCs are active, with infall, outflow, and
collapse; the spectra are abundant especially in deuterium species.
Conclusions. We observe many blueshifted and redshifted profiles,
respectively, with and toward the same core. This
case can be well explained by model "envelope expansion with core collapse
(EECC)".Comment: 24 pages, 11 figures, 4 tables. To be published in A&A. The
resolutions of the pictures are cut dow
Poly[tetraaquadi-μ4-oxalato-potassiumytterbium(III)]
In the title compound, [KYb(C2O4)2(H2O)4]n, the YbIII ion lies on a site of symmetry in a dodecahedral environment defined by eight O atoms from four oxalate ligands. The K atom lies on a different axis and is coordinated by four O atoms from four oxalate ligands and four water O atoms. The oxalate ligand has an inversion center at the mid-point of the C—C bond. The metal ions are linked by the oxalate ligands into a three-dimensional framework. O—H⋯O hydrogen bonding is present in the crystal structure
Miniaturization of Branch-Line Coupler Using Composite Right/Left-Handed Transmission Lines with Novel Meander-shaped-slots CSSRR
A novel compact-size branch-line coupler using composite right/left-handed transmission lines is proposed in this paper. In order to obtain miniaturization, composite right/left-handed transmission lines with novel complementary split single ring resonators which are realized by loading a pair of meander-shaped-slots in the split of the ring are designed. This novel coupler occupies only 22.8% of the area of the conventional approach at 0.7 GHz. The proposed coupler can be implemented by using the standard printed-circuit-board etching processes without any implementation of lumped elements and via-holes, making it very useful for wireless communication systems. The agreement between measured and stimulated results validates the feasible configuration of the proposed coupler
Matrix inequalities involving the Khatri-Rao product
summary:We extend three inequalities involving the Hadamard product in three ways. First, the results are extended to any partitioned blocks Hermitian matrices. Second, the Hadamard product is replaced by the Khatri-Rao product. Third, the necessary and sufficient conditions under which equalities occur are presented. Thereby, we generalize two inequalities involving the Khatri–Rao product
6,6′-Dimethoxy-2,2′-[(cyclohexane-1,2-diyl)bis(nitrilomethylidyne)]diphenol
The molecule of the title compound, C22H26N2O4, has two azomethine linkages, both of which are in an E configuration. The cyclohexyl ring adopts a chair conformation. The dihedral angle between the benzene rings is 66.57 (9)°. The molecular structure is stabilized by two intramolecular O—H⋯N hydrogen bonds
Nuclear superfluidity for antimagnetic rotation in Cd and Cd
The effect of nuclear superfluidity on antimagnetic rotation bands in
Cd and Cd are investigated by the cranked shell model with the
pairing correlations and the blocking effects treated by a particle-number
conserving method. The experimental moments of inertia and the reduced
transition values are excellently reproduced. The nuclear superfluidity is
essential to reproduce the experimental moments of inertia. The two-shears-like
mechanism for the antimagnetic rotation is investigated by examining the shears
angle, i.e., the closing of the two proton hole angular momenta, and its
sensitive dependence on the nuclear superfluidity is revealed.Comment: 14 pages, 4 figure
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