Related papers: Circumstellar environment of RX Puppis
We present Period-Luminosity and Period-Luminosity-Color relations at maximum-light for Mira variables in the Magellanic Clouds using time-series data from the Optical Gravitational Lensing Experiment (OGLE-III) and {\it Gaia} data release…
We present the analysis of photometric and spectroscopic data of two bright Galactic Cepheids, X Puppis and XX Sagittarii. Based on the available data in the literature as well as own observations spanning 75 years, we conclude that both…
Extreme outbursts in young stars may be a common stage of pre-main-sequence stellar evolution. These outbursts, caused by enhanced accretion and accompanied by increased luminosity, can also strongly impact the evolution of the…
Modeling observations of the archetypal debris disk around $\beta$ Pic, obtained in 2023 January with the MIRI MRS on board JWST, reveals significant differences compared with that obtained with the IRS on board Spitzer. The bright 5 - 15…
Aims: We report the discovery that Mira variables with and without absorption lines of the element technetium (Tc) occupy two different regions in a diagram of near- to mid-infrared colour versus pulsation period. Tc is an indicator of a…
Polarized extinction and emission from dust in the interstellar medium (ISM) are hard to interpret, as they have a complex dependence on dust optical properties, grain alignment and magnetic field orientation. This is particularly true in…
Diffuse envelopes around Mira variables are among the most important sources influencing the chemical evolution of galaxies. However they represent an observational challenge because of their complex spectral features and their rapid…
(abridged) The dust content of the universe is primarily explored via its interaction with stellar photons, producing interstellar extinction. However, owing to the physical extension of the observing beam, observations may detect scattered…
We establish a sample of 370 Mira variables that are likely near the Galactic center (GC). The sources have been selected from the OGLE and BAaDE surveys based on their sky coordinates, OGLE classifications, and BAaDE maser-derived…
GRS 1915+105 is a well-known X-ray binary system composed of a black hole with a low-mass companion star and is recognized for emitting relativistic jets. Imazato et al. (2021) performed extensive polarimetry in a near-infrared (NIR) Ks…
Mira variables change visual light by up to 8 magnitudes over their roughly yearly cycle. Here we present a simple explanation for the extremely large amplitudes of light curves of oxygen-rich Mira variables. Metallic oxides, such as TiO,…
We present dust continuum observations of the protoplanetary disk surrounding the pre-main sequence star AS 209, spanning more than an order of magnitude in wavelength from 0.88 to 9.8 mm. The disk was observed with sub-arcsecond angular…
The dust extinction curve is a critical component of many observational programs and an important diagnostic of the physics of the interstellar medium. Here we present new measurements of the dust extinction curve and its variation towards…
A quantitative interpretation of the observed relation between the interstellar linear polarization curve parameters $K$ and $\lambda_{\max}$ characterizing the width and the wavelength of a polarization maximum, respectively, is given. The…
Optical polarimetry is an effective way of probing the environment of supernova for dust. We acquired linear HST ACS/WFC polarimetry in bands $F475W$, $F606W$, and $F775W$ of the supernova (SN) 2014J in M82 at six epochs from $\sim$277 days…
RX Pup is a symbiotic binary which experienced a nova outburst in the 1970's. Here we report a discovery of a ~1300 year old nova shell around the system and a possible detection of a ~7000 year old nova shell. Together with the nova shell…
Be/X-ray binaries are the most numerous group of high-mass X-ray binaries. Their long-term optical and infrared variability reflects the evolution of the circumstellar disk around the luminous companion. This variability manifests…
Stars with masses between roughly 1 and 8~$M_\odot$ end their lives on the asymptotic giant branch (AGB), when intense mass loss takes place. The outflows are generally accepted to be driven by radiation pressure acting on dust grains that…
Published data for large amplitude asymptotic giant branch variables in the Large Magellanic Cloud are re-analysed to establish the constants for an infrared (K) period-luminosity relation of the form: Mk=rho[log P-2.38] + delta. A slope of…
Interstellar dust appears in a number of roles in the interstellar medium. Historically, the most familiar one is as a source of extinction in the optical. Absorbed optical and ultraviolet light heats the dust, whence infrared (including…