Search Publications
Spatially resolved dust emission of extremely metal-poor galaxies*
Li, Aigen; Armus, Lee; Helou, George +4 more
We present infrared (IR) spectral energy distributions (SEDs) of individual star-forming regions in four extremely metal-poor (EMP) galaxies with metallicity Z ≲ Z⊙/10 as observed by the Herschel Space Observatory. With the good wavelength coverage of the SED, it is found that these EMP star-forming regions show distinct SED shapes as c…
H-ATLAS: the far-infrared properties of galaxies in and around the Coma cluster
Ibar, E.; Dunne, L.; Dye, S. +12 more
We describe a far-infrared survey of the Coma cluster and the galaxy filament it resides within. Our survey covers an area of ∼150 deg2 observed by Herschel H-ATLAS (Herschel Astrophysical Terahertz Large Area Survey) in five bands at 100, 160, 250, 350 and 500 µm. The SDSS spectroscopic survey (mr ≤ 17.8) is used to de…
Evidence for variable, correlated X-ray and optical/IR extinction towards the nearby, pre-main-sequence binary TWA 30
Kastner, J. H.; Alcalá, J. M.; Principe, David A. +2 more
We present contemporaneous XMM-Newton X-ray and ground-based optical/near-IR spectroscopic observations of the nearby (D ≈ 42 pc), low-mass (mid-M) binary system TWA 30A and 30B. The components of this wide (separation ∼3400 au) binary are notable for their nearly edge-on disc viewing geometries, high levels of variability, and evidence for collim…
A tale of two tails: exploring stellar populations in the tidal tails of NGC 3256
Gronwall, Caryl; Ciardullo, Robin; Charlton, Jane +7 more
We have developed an observing programme using deep, multiband imaging to probe the chaotic regions of tidal tails in search of an underlying stellar population, using NGC 3256's 400 Myr twin tidal tails as a case study. These tails have different colours of u - g = 1.05 ± 0.07 and r - I = 0.13 ± 0.07 for NGC 3256W, and u - g = 1.26 ± 0.07 and r -…
Results from DROXO. IV. EXTraS discovery of an X-ray flare from the Class I protostar candidate ISO-Oph 85
Salvaterra, R.; Haberl, F.; Tiengo, A. +15 more
X-ray emission from young stellar objects (YSOs) is a key ingredient in understanding star formation. For the early, protostellar (Class I) phase, a very limited (and controversial) quantity of X-ray results is available to date. Within the EXTraS (Exploring the X-ray Transient and variable Sky) project, we have discovered transient X-ray emission…
The Broken Lane of a Type II Radio Burst Caused by Collision of a Coronal Shock with a Flare Current Sheet
Lin, Jun; Wang, Min; Gao, Guannan +3 more
We investigated a peculiar metric type II solar radio burst with a broken lane structure that was observed on November 13, 2012. In addition to the radio data, we also studied the data in other wavelengths. The bursts were associated with two coronal mass ejections (CMEs) and two flares that originated from Active Region AR 11613. A long current s…
Optical tracking of deep-space spacecraft in Halo L2 orbits and beyond: The Gaia mission as a pilot case
Buzzoni, Alberto; Altavilla, Giuseppe; Galleti, Silvia
We tackle the problem of accurate optical tracking of distant man-made probes, on Halo orbit around the Earth-Sun libration point L2 and beyond, along interplanetary transfers. The improved performance of on-target tracking, especially when observing with small-class telescopes is assessed providing a general estimate of the expected S/N ratio in …
A journey through scales
Retinò, Alessandro
Direct satellite observations of energy transfer between large and small space plasma scales contribute to our understanding of how matter in the Universe gets hot.
Neutral Hydrogen and Its Emission Lines in the Solar Corona
Vial, Jean-Claude; Chane-Yook, Martine
Since the Lyman-α rocket observations of Gabriel (Solar Phys.21, 392, 1971), it has been realized that the hydrogen (H) lines could be observed in the corona and that they offer an interesting diagnostic for the temperature, density, and radial velocity of the coronal plasma. Moreover, various space missions have been proposed to measure the coron…
Detection of coronal mass ejections using AdaBoost on grayscale statistic features
Guo, Juan; Zhang, Ling; Yin, Jian-qin +2 more
We present an automatic algorithm to detect coronal mass ejections (CMEs) in Large Angle Spectrometric Coronagraph (LASCO) C2 running difference images. The algorithm includes 3 steps: (1) split the running difference images into blocks according to slice size and analyze the grayscale statistics of the blocks from a set of images with and without…