3,965 research outputs found
Studying newborn neutron stars by the transient emission after stellar collapses and compact binary mergers
The formation of neutron stars (NSs), both from collapses of massive stars
and mergers of compact objects, can be usually indicated by bright transients
emitted from explosively-ejected material. In particular, if the newborn NSs
can rotate at a millisecond period and have a sufficiently high magnetic field,
then the spin-down of the NSs would provide a remarkable amount of energy to
the emitting material. As a result, super-luminous supernovae could be produced
in the massive stellar collapse cases, while some unusual fast evolving and
luminous optical transients could arise from the cases of NS mergers and
accretion-induced collapses of white dwarfs. In all cases, if the dipolar
magnetic fields of the newborn NSs can be amplified to be as high as
G, a relativistic jet could be launched and then a gamma-ray burst can be
produced as the jet successfully breaks out from the surrounding
nearly-isotropic ejected material.Comment: 10 pages, 9 pictures, to appear in the AIP Proceedings of the
Xiamen-CUSTIPEN Workshop on the EOS of Dense Neutron-Rich Matter in the Era
of Gravitational Wave Astronomy, Jan. 3-7, Xiamen, Chin
A CASE STUDY ON THE CONSTRUCTION OF TEACHERS’ PROFESSIONAL ROLE IDENTITY IN HIGHER VOCATIONAL COLLEGES UNDER THE BACKGROUND OF EDUCATIONAL PSYCHOLOGY - FROM THE PERSPECTIVE OF SOCIAL AND CULTURAL CONSTRUCTIVISM
The transition form factors and angular distributions of the decay supported by baryon spectroscopy
We calculate the weak transition form factors of the
transition, and further calculate the angular
distributions of the rare decays () with unpolarized
and massive leptons. The form factors are calculated by the
three-body light-front quark model with the support of numerical wave functions
of and from solving the semirelativistic potential
model associated with the Gaussian expansion method. By fitting the mass
spectrum of the observed single bottom and charmed baryons, the parameters of
the potential model are fixed, so this strategy can avoid the uncertainties
arising from the choice of a simple harmonic oscillator (SHO) wave function of
the baryons. With more data accumulated in the LHCb experiment, our result can
help for exploring the decay and deepen
our understanding on the processes.Comment: 21 pages, 9 figures. Accepted by Phys. Rev.
2-(4-Isopropyl-4-methyl-5-oxo-4,5-dihydro-1H-imidazol-2-yl)-5-methylnicotinic acid
In the title herbicideh/phytocide, known as imazapic, C14H17N3O3, the pyridine and imidazole rings are almost coplanar [dihedral angle = 3.08 (5)°]. An intramolecular O—H⋯N hydrogen bond occurs. In the crystal, an N—H⋯O hydrogen bond links molecules into a chain parallel to [010]
[μ-4-Benzoyl-1-(1-oxido-2-naphthylcarbonyl)thiosemicarbazidato(4−)]bis[pyridinecopper(II)]
In the title dinuclear complex, [Cu2(C19H11N3O3S)(C5H5N)2], the two CuII centers have different coordination environments, viz. N2OS and N2O2, each exhibiting a distorted square-planar geometry. π–π interactions between the aromatic rings of neighbouring complexes [centroid–centroid distance = 3.856 (5) Å] link pairs of molecules into centrosymmetric dimers, which are further packed into stacks along the b axis with relatively short Cu⋯Cu separations of 3.482 (1) Å. Weak intermolecular C—H⋯N hydrogen bonds help to consolidate the crystal packing
1,4-Bis(4-pyridylmethoxy)benzene
The molecule of the title compound, C18H16N2O2, lies about a center of inversion. The central phenylene ring is aligned at 62.7 (1)° with respect to the pyridyl ring. In the crystal, weak intermolecular C—H⋯N hydrogen bonds link molecules into sheets parallel to (104). C—H⋯O interactions are also present
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