Search Publications
A Solar Magnetic-fan Flaring Arch Heated by Nonthermal Particles and Hot Plasma from an X-Ray Jet Eruption
Lee, Kyoung-Sun; Hara, Hirohisa; Panesar, Navdeep K. +10 more
We have investigated an M1.3 limb flare, which develops as a magnetic loop/arch that fans out from an X-ray jet. Using Hinode/EIS, we found that the temperature increases with height to a value of over 107 K at the loop top during the flare. The measured Doppler velocity (redshifts of 100-500 km s-1) and the nonthermal veloci…
A Herschel Mapping of [{C}{II}],[{O}{I}], and [{O}{III}] Lines from the Circumnuclear Region of M31
Smith, Matthew W. L.; Gao, Yu; Li, Zhiyuan +1 more
The circumnuclear region of M31, consisting of multiphase interstellar media, provides a close-up view of the interaction of the central supermassive black hole and surrounding materials. Far-infrared (FIR) fine-structure lines and their flux ratios can be used as diagnostics of physical properties of the neutral gas in this region. Here we presen…
Search for non-thermal X-ray emission in the colliding wind binary Cygnus OB2 #8A
Nazé, Y.; Rauw, G.; Pittard, J. M. +1 more
Aims: Cyg OB2 #8A is a massive O-type binary displaying strong non-thermal radio emission. Owing to the compactness of this binary, emission of non-thermal X-ray photons via inverse Compton scattering is expected.
Methods: We first revised the orbital solution for Cyg OB2 #8A using new optical spectra. We then reduced and analysed X-ray …
Wray 15-906: a candidate luminous blue variable discovered with WISE, Herschel, and SALT
Berdnikov, L. N.; Gvaramadze, V. V.; Kniazev, A. Y. +1 more
We present the results of study of the Galactic candidate luminous blue variable Wray 15-906, revealed via detection of its infrared circumstellar shell (of ≈2 pc in diameter) with the Wide-field Infrared Survey Explorer and the Herschel Space Observatory. Using the stellar atmosphere code CMFGEN and the Gaia parallax, we found that Wray 15-906 is…
Testing massive star evolution, star-formation history, and feedback at low metallicity. Photometric analysis of OB stars in the SMC Wing
Hamann, Wolf-Rainer; Gallagher, John S.; Ramachandran, Varsha +2 more
Context. The supergiant ionized shell SMC-SGS 1 (DEM 167), which is located in the outer Wing of the Small Magellanic Cloud (SMC), resembles structures that originate from an energetic star-formation event and later stimulate star formation as they expand into the ambient medium. However, stellar populations within and surrounding SMC-SGS 1 tell a…
Spatially resolving the chemical composition of the planet building blocks
Matter, A.; Lopez, B.; Pignatale, F. C.
The inner regions of protoplanetary discs (from ∼0.1 to 10 au) are the expected birthplace of planets, especially telluric. In those high-temperature regions, solids can experience cyclical annealing, vapourisation, and recondensation. Hot and warm dusty grains emit mostly in the infrared domain, notably in N-band (8-13 µm). Studying their f…
Local galaxies with compact cores as the possible descendants of massive compact quiescent galaxies at high redshift
Fan, Lu-Lu; Gao, Ying
In order to test a possible evolutionary scenario of high-z compact quiescent galaxies (cQGs) that they can survive as local compact cores embedded in local massive galaxies with different morphology classes, we explore the star formation histories of local compact cores according to their spectral analysis. We build a sample of 182 massive galaxi…
Accuracy of view factor calculations for digital terrain models of comets and asteroids
Rezac, L.; Zhao, Y.
Context. Detailed shape and topographic models coupled with sophisticated thermal physics are critical elements to proper characterization of surfaces of small bodies in our solar system. Calculations of self-heating effects are especially important in the context of thermal evolution of non-convex surfaces, including craters, cracks, or openings …
On the Long Range Clustering of Global Seismicity and its Correlation With Solar Activity: A New Perspective for Earthquake Forecasting
Marchitelli, Vito; Troise, Claudia; Harabaglia, Paolo +2 more
Large earthquakes occurring worldwide have long been recognized to be non Poisson distributed, so involving some large scale correlation mechanism, which could be internal or external to the Earth. We have recently demonstrated this observation can be explained by the correlation of global seismicity with solar activity. We inferred such a clear c…
Statistical Analysis of Asymmetric Sunspot Decay Observed by Hinode
Imada, Shinsuke; Kato, Shota; Fujiyama, Masashi
We statistically studied the transport of magnetic flux in and around sunspots using a magnetic-element tracking technique to investigate whether sunspot-decay processes are isotropic. Using this method, we detected moving magnetic features (MMFs). The observed radius of an MMFs region was approximately 1.7 times the sunspot radius; furthermore, t…