相关论文: Recent Developments in Maser Theory

Water fountains (WFs) are thought to be objects in the morphological evolution of the circumstellar envelopes of low- and intermediate-mass evolved stars, transitioning from spherically symmetric to asymmetric shapes. We used databases of…

Circumstellar disks are an integral part of the star formation process and the sites where planets are formed. Understanding the physical processes that drive their evolution, as disks evolve from optically thick to optically thin, is…

Variability in gravitationally lensed quasars can be due to intrinsic fluctuations of the quasar or due to ``microlensing'' by compact objects along the line of sight. If disentangled from each other, microlens-induced variability can be…

Mass loss is a key process in the evolution of massive stars, and must be understood quantitatively to be successfully included in broader astrophysical applications. In this review, we discuss various aspects of radiation driven mass loss,…

Key results from the literature pertaining to a class of nonsingular black hole mimickers are explored. The family of candidate spacetimes is for now labelled the `black-bounce' family, stemming from the original so-called `Simpson--Visser'…

Star formation is a multi-scale, multi-physics problem ranging from the size scale of molecular clouds ($\sim$10s pc) down to the size scales of dense prestellar cores ($\sim$0.1 pc) that are the birth sites of stars. Several physical…

Context: OH masers trace diverse physical processes, from the expanding envelopes around evolved stars to star-forming regions or supernovae remnants. Aims: We identify the ground-state OH masers at 18cm wavelength in the area covered by…

We develop a geometry-first model that maps measured thin-disk water megamaser observables--sky angles, frequency shifts, their secular drifts and the angular redshift rate--to the black hole parameters in a generic static, spherically…

This review summarizes a few of the frontiers of Galactic center research that are currently the focus of considerable activity and attention. It is aimed at providing a necessarily incomplete sketch of some of the timely work being done on…

Understanding the matter cycle in the interstellar medium of galaxies from the assembly of clouds to star formation and stellar feedback remains an important and exciting field in comtemporary astrophysics. Many open questions regarding…

We review basic physics of line-driven stellar winds of OB stars. We discuss elementary processes due to which stellar winds are accelerated on a microscopic level. We show how these microscopic processes may enable the outflow and how they…

Cepheid stars are crucial objects for a variety of topics that range from stellar pulsation and the evolution of intermediate-mass stars to the understanding the structure of the Galaxy and the Universe through the distance measurements…

We present the results of models that were designed to study all possible water maser transitions in the frequency range 0-1.91THz, with particular emphasis on maser transitions that may be generated in evolved-star envelopes and observed…

General issues concerning the regularization of supersymmetric theories using dimensional regularization and dimensional reduction are reviewed. Recent progress on problems of dimensional reduction related to factorization, supersymmetry,…

We review recent advances in our understanding of massive stars through the analysis of their spectra. Improvements in model atmospheres and analysis methods are briefly discussed. Results obtained for stars in the Local Group are compared…

Bipolar molecular outflows have been observed and studied extensively in the past, but some recent observations of periodic variations in maser intensity pose new challenges. Even quasi-periodic maser flares have been observed and reported…

Since the discovery of the first bona-fide brown dwarfs and extra-solar planets in 1995, the field of low mass stars and substellar objects has considerably progressed, both from theoretical and observational viewpoints.Recent developments…

Here we review various themes of current research within mesoscopic magnetic systems.

Observations of interstellar gas-phase and solid-state species in the 2.4-200 micron range obtained with the spectrometers on board the Infrared Space Observatory are reviewed. Lines and bands due to ices, polycyclic aromatic hydrocarbons,…

I review recent advances in the determination of the cosmic history of star formation, and its relevance in our understanding of the formation of structures. I emphasize the importance of dust reprocessing in the high--z universe, as…