相关论文: Maser polarization through anisotropic pumping
In this paper we re-analyse the amplification process of broadband continuum radiation by astronomical masers in one-dimensional case. The basic equations appropriate for the scalar maser and the random nature of the maser radiation field…
We report polarization tomography experiments on metallic nanohole arrays with square and hexagonal symmetry. As a main result, we find that a fully polarized input beam is partly depolarized after transmission through a nanohole array.…
We analyze full-polarization VLBA data of ground-state, main-line OH masers in 18 massive star-forming regions previously presented in a companion paper. The OH masers often arise in the shocked neutral gas surrounding ultracompact Hii…
We present the first 6.7 GHz methanol maser linear polarization map of the extended filamentary maser structure around the compact HII region W3(OH). The methanol masers show linear polarization up to 8 per cent and the polarization angles…
The surfaces of neutron stars are sources of strongly polarized soft X rays due to the presence of strong magnetic fields. Radiative transfer mediated by electron scattering and free-free absorption is central to defining local surface…
Accurately measuring the magnetic field in the ISM is essential for understanding star-formation processes. We searched archival data of the Submillimeter Array (SMA) for evidence of circular polarization in common molecular tracers, most…
Magnetic fields have only recently been included in theoretical simulations of high-mass star formation. The simulations show that magnetic fields play an important role in the formation and dynamics of molecular outflows. Masers, in…
In an earlier paper, we introduced a model for pulsars in which non-radial oscillations of high spherical degree (\el) aligned to the magnetic axis of a spinning neutron star were able to reproduce subpulses like those observed in…
Context. Maser emission is a strong tool for studying high mass star forming regions and their evolutionary stages. OH masers in particular can trace the circumstellar material around protostars and determine their magnetic field strengths…
Sizable hyperpolarisation, i.e. an imbalance of the occupation numbers of nuclear spins in a sample deviating from thermal equilibrium, is needed in various fields of science. For example, hyperpolarised tracers are utilised in magnetic…
We present the first circular polarization measurements of circumstellar water masers around a sample of late-type stars. These observations are used to obtain the magnetic field strength in the water maser region with both an LTE and…
We consider an inhomogeneous model and independently an anisotropic model of primordial power spectrum in order to describe the observed hemispherical anisotropy in Cosmic Microwave Background Radiation. This anisotropy can be parametrized…
A novel polarization-modulation transient method has been developed for studying fast anisotropic relaxation in electronic excited states of polyatomic and biologically relevant molecules under excitation with femtosecond laser pulses. The…
Class I methanol masers are found to be good tracers of the interaction between outflows from massive young stellar objects with their surrounding media. Although polarization observations of Class II methanol masers have been able to…
We present a novel approach to model ultrafast time-dependent nonlinear optical polarization sensitive signals emitted from randomly-oriented molecules. By projecting the laboratory-frame analyzer polarization axis into the molecular frame…
The propagation of polarized emission in pulsar magnetosphere is investigated in this paper. The polarized waves are generated through curvature radiation from the relativistic particles streaming along curved magnetic field lines and…
We present high angular resolution observations of OH maser emission towards the high-mass star forming region IRAS 06056+2131. The observations were carried out using the UK radio interferometer array, Multi-Element Radio Linked…
We report high nuclear polarization of 1.2 mbar 3He gas in a sealed cell in magnetic fields up to 5 T using Metastability Exchange Optical Pumping (MEOP). The creation of a highly polarized 3He gas target for use in the 5 T field of…
Polariton lasing has recently been observed in strongly coupled crystalline anthracene microcavities. A simple model is developed describing the onset of the non-linear threshold based on a master equation including the relevant relaxation…
The full theory of polarized SiO maser emission from the near-circumstellar environment of Asymptotic Giant Branch stars has been the subject of debate, with theories ranging from classical Zeeman origins to predominantly non-Zeeman…