Related papers: A Straight and Narrow Ionized Filament
Filaments are a key step on the path that leads from molecular clouds to star formation. However, their characteristics are heavily debated, and the exact processes that lead to their formation and fragmentation into dense cores still…
The extended supernova remnant G 116.5+1.1 was observed in the optical emission lines of Halpha+[N II], [S II] and [O III]; deep long-slit spectra were also obtained. The morphology of the remnant's observed emission is mainly diffuse and…
We present observations of the formation process of a small-scale filament on the quiet Sun during 5-6 February 2016 and investigate its formation cause. Initially, a small dipole emerged and its associated arch filament system was found to…
This is the second of two papers examining Spitzer Infrared Spectrograph (IRS) observations of the ultraluminous X-ray source (ULX) in Holmberg II. Here we perform detailed photoionization modeling of the infrared lines. Our analysis…
A large, faint nebula was unexpectedly discovered near M31 using narrowband [O III] images. Its apparent size and the lack of a clear counterpart at other wavelengths make it unique and challenging to explain. We aim to determine whether…
Flare ribbons serve as chromospheric footprints of energy deposition resulting from particle acceleration during magnetic reconnection. Their fine-scale structure provides a valuable tool for probing the dynamics of the flare reconnection…
A giant, quiet-Sun filament was observed with the high-resolution Echelle spectrograph at the Vacuum Tower Telescope at Observatorio del Teide on 2011 November 15. A mosaic of spectra (10 maps of 100" X 182") was recorded simultaneously in…
Recent Herschel observations have confirmed that filaments are ubiquitous in molecular clouds and suggest that irrespectively of the column density, there is a characteristic width of about 0.1 pc whose physical origin remains unclear. We…
Infrared dark clouds are massive, dense clouds seen in extinction against the IR Galactic background. Many of these objects appear to be on the verge of star and star cluster formation. Our aim is to understand the physical properties of…
We present images of the supernova remnant N206 in the LMC, taken with ATCA at wavelengths of 3 and 6 cm. Based on our data and previously published flux densities, the spectral index of N206 is -0.20 +- 0.07. The 6-cm radio morphology…
The Orion-Eridanus superbubble, formed by the nearby Orion high mass star-forming region, contains multiple bright H$\alpha$ filaments on the Eridanus side of the superbubble. We examine the implications of the H$\alpha$ brightnesses and…
We have conducted aperture polarimetry of ~500 stars of the Orion Nebula Cluster (ONC) in M42 based on our wide-field (~8'\times 8') $JHKs$ band polarimetry. Most of the near-infrared (NIR) polarizations are dichroic, with position angles…
Large-scale filaments ubiquitously exist in the Galactic interstellar medium, and their radial profiles offer insights into their formation mechanisms. We present a statistical analysis of molecular hydrogen column density ($\rm N(H_2)$)…
We have designed and made an optical fibre that guides an approximate Airy pattern as one of its guided modes. The fibre's attenuation was 11.0 dB/km at 1550 nm wavelength, the match between the fibre's mode and the ideal infinite Airy…
Recent \herschel\ and \planck\ observations of submillimeter dust emission revealed the omnipresence of filamentary structures in the interstellar medium (ISM). The ubiquity of filaments in quiescent clouds as well as in star-forming…
New optical images of the young SNR G292.0+1.8, obtained from the 0.9-m telescope at CTIO, show a more extensive network of filaments than had been known previously. Filaments emitting in [O III] are distributed throughout much of the 8…
Wide-field (~8' x 8') and deep near-infrared (JHKs bands) polarization images of the Orion nebulae (IRNe) around young stellar objects (YSOs), both massive and low-mass. We found the IRNe around both IRc2 and BN to be very extensive,…
I review the basic properties of low-ionization nuclear emission-line regions (LINERs), as well as the main ionization mechanisms thus far proposed for them. There is substantial heterogeneity among LINERs, especially those with extended…
Deep Halpha images of portions of a faint 3 x 4 degree Halpha shell centered at l = 159.6 deg, b = 7.3 deg seen on the Virginia Tech Spectral Line Survey images revealed the presence of several thin emission filaments along its eastern…
Quiescent filaments appear as absorption features on the solar disk when observed in chromospheric lines and at continuum wavelengths in the millimeter (mm) range. Active region (AR) filaments are their small-scale, low-altitude analogues,…