REGISTRATI Chiudi

Notizie da 5 fonti

19 set 2014 18:00

Focus: Curvy Photon Trajectories Could Be Detectable

Quantum mechanics permits particles to follow bizarre, looping and curving trajectories, usually with very low probability. But a calculation shows that in some cases, these paths can have significant and possibly measurable effects. Published Fri Sep 19, 2014

fisica | physics - spotlighting exceptional research

18 set 2014 18:00

Synopsis: More Dark Matter Hints from Cosmic Rays?

A particle detector onboard the International Space Station has revealed differences between the spectrum of cosmic-ray positrons and electrons, which might be a hint of dark matter annihilation processes. Published Thu Sep 18, 2014

fisica | physics - spotlighting exceptional research

17 set 2014 18:00

Synopsis: Patchy Particles without the Patches

Mobile DNA strands could provide a different way to patch together DNA-coated particles to form colloidal structures whose structure and function can be tailored. Published Wed Sep 17, 2014

fisica | physics - spotlighting exceptional research

16 set 2014 18:00

Synopsis: Relativity is Right on Time, Again

An experiment with fast-moving ions verifies relativistic time dilation to a new level of precision, placing constraints on certain quantum gravity theories. Published Tue Sep 16, 2014

fisica | physics - spotlighting exceptional research

15 set 2014 18:00

Viewpoint: Observing the Great Spin and Orbital Swap

The experimental observation of spin-orbital exchange interactions in ultracold atoms opens a window for the exploration of poorly understood magnetic behaviors. Published Mon Sep 15, 2014

fisica | physics - spotlighting exceptional research

12 set 2014 18:00

Focus: Electron Handedness Affects Gas Molecule Breakup

Experiments show that beams of left- or right-handed electrons are not equal-opportunity destroyers of molecules having two mirror-image forms, which supports the idea that primordial cosmic rays generated the asymmetry in biological molecules. Published Fri Sep 12, 2014

fisica | physics - spotlighting exceptional research

12 set 2014 04:00

Magnetic phase transition and magnetocaloric effect in Mn 1– x Zn x CoGe alloys

The magnetic phase transition and magnetocaloric effect are studied in a series of Mn 1− x Zn x CoGe ( x = 0.01, 0.02, 0.04, and 0.08) alloys. By introducing a small quantity of Zn element, the structural transformation temperature of the MnCoGe alloy is greatly reduced and a first-order magnetostructural transition is observed. Further increasing the Zn concentration results in a second-order ferromagnetic transition. Large room-temperature magnetocaloric effects with small magnetic hysteresis are obtained in alloys with x = 0.01 and 0.02, which suggests their potential application in magnetic refrigeration.

fisica | chinese physics b latest papers

12 set 2014 04:00

Homotopic mapping solitary traveling wave solutions for the disturbed BKK mechanism physical model

Using the trial equation method, a Broer—Kau—Kupershmidt (BKK) mechanism physical model is obtained, and the exact and approximate solitary traveling wave solutions are found. As an example, it is pointed out that the solitary traveling wave approximate solutions have better accurate degree by using the homotopic mapping theory.

fisica | chinese physics b latest papers

12 set 2014 04:00

Scattering of a general partially coherent beam from a diffuse target in atmospheric turbulence

The second-order and fourth-order statistical moments of the speckle field from a diffuse target in atmospheric turbulence are studied which have great influence on the performance of lidar systems. By expanding a general rotationally symmetric beam as a sum of Gaussian—Schell model (GSM) beams, the mean intensity of the general beam propagating over a distance in an atmospheric turbulence is formulated. Expressions for the degree of coherence (DOC) and the normalized intensity variance of the scattered field of a general beam from a rough surface in turbulence are derived based on the extended Huygens—Fresnel principle. The general expressions reduce to the well-known forms for a GSM beam. Another example for the general beam used in this paper is the collimated flat-topped beam. The results of both kinds of beams show that the intensity profile on the target plane is a key factor affecting the statistical characteristics of the speckle field. A larger beam spot on the target p...

fisica | chinese physics b latest papers

12 set 2014 04:00

Erratum: Classical interpretations of relativistic precessions

We point out an error in Eq. (19) in our original paper [ Chin. Phys. B 23 040402 (2014)] and present the correct equation.

fisica | chinese physics b latest papers