相关论文: Research on the quantity and brightness evolution …

The dark and dynamic parts of the Galaxy, including the bulk shape and movement of the Galactic Bulge and characteristics of dark compact object populations, such as a hypothetical population of primordial black holes (PBHs), are difficult…

To deepen the analysis of the photometric properties of the umbra of a sunspot, we study proper motions of small features such as umbral dots (UDs) inside a single sunspot observed by the Solar Optical Telescope of Hinode close to the disk…

The K-band Hubble diagram for a sample of brightest cluster galaxies (BCGs) in the redshift range 0<z<1 shows a very small scatter (0.3 magnitudes r.m.s). The BCGs exhibit very little luminosity evolution in this redshift range: if q_0=0.0…

Context: The evolution of solar active regions is still not fully understood. The growth and decay of active regions have mostly been studied in case-by-case studies. Aims: Instead of studying the evolution of active regions case by case,…

Small scale magnetic fields can be observed on the Sun in G-band filtergrams as MBPs (magnetic bright points) or identified in spectro-polarimetric measurements due to enhanced signals of Stokes profiles. These magnetic fields and their…

We investigate surface brightness profiles (SBPs) of dwarf galaxies in field, group, and cluster environments. With deep $BVI$ images from the Korea Microlensing Telescope Network Supernova Program, SBPs of 38 dwarfs in the NGC 2784 group…

Timing analysis is a powerful tool with which to shed light on the still obscure emission physics and geometry of the prompt emission of GRBs. Fourier power density spectra (PDS) characterise time series as stochastic processes and can be…

Small-scale magnetic features are present everywhere in the solar photosphere. Theoretical models, numerical calculations, and simulations describing the formation of these features have existed for a few decades, but there are only a few…

Context. Small bodies change their brightness due to different motives: Rotation along their axis or axes, combined with irregular shapes and/or changing surface properties, or changes in the geometry of observations. In this work, we…

Since their discovery twenty year ago, transition region bright points (TRBPs) have never been observed spectroscopically. Bright point properties have not been compared with similar transition region and coronal structures. In this work we…

We present a statistical study of the detectability of lightcurves of Kuiper Belt objects (KBOs). Some Kuiper Belt objects display lightcurves that appear "flat", i.e., there are no significant brightness variations within the photometric…

Substructures - dark lanes and tails - of umbral dots (UDs) were predicted by numerical simulations of magnetoconvection. We analyse a 6 h 23 min time series of broadband images of a large umbra in the active region NOAA 10634, acquired…

We present a 106-minute TiO (705.7nm) time series of high spatial and temporal resolution that contains thousands of umbral dots (UDs) in a mature sunspot in the active region NOAA 10667 at $\mu$=0.95. The data were acquired with the 1-m…

Cool-core clusters are characterized by strong surface brightness peaks in the X-ray emission from the Intra Cluster Medium (ICM). This phenomenon is associated with complex physics in the ICM and has been a subject of intense debate and…

Realistic 3D radiative MHD simulations reveal the magneto-convective processes underlying the formation of the photospheric fine structure of sunspots, including penumbral filaments and umbral dots. Here we provide results from a…

We present experiments on the collective dynamics of macroscopic photoactive self-propelled particles subjected to spatiotemporally varying excitation. The particles move within an arena divided into two regions with different illumination…

The group of lambda Bootis type stars comprises late B- to early F-type, Population I objects which are basically metal weak, in particular the Fe group elements, but with the clear exception of C, N, O and S. The present work is a…

Dwarf galaxies are important tracers of small-scale cosmological structure, yet much of our knowledge about these systems comes from the limited sample of dwarf galaxies within the Local Group. To make a comprehensive inventory of dwarf…

We present a new technique for monitoring microlensing activity even in highly crowded fields, and use this technique to place limits on low-mass MACHOs in the haloes of M31 and the Galaxy. Unlike present Galactic microlensing surveys, we…

Small-scale Brightenings (SBs) are commonly observed in the transition region that separates the solar chromosphere from the corona. These brightenings, omnipresent in active region patches known as "moss" regions, could potentially…