Search Publications
An Investigation on the Morphological and Mineralogical Characteristics of Posidonius Floor Fractured Lunar Impact Crater Using Lunar Remote Sensing Data
Salem, Imen Ben; Sharma, Manish; Kumaresan, P. R. +4 more
Lunar floor-fractured craters (FFCs) are a distinguished type of crater found on the surface of the Moon with radial, concentric, and/or polygonal fractures. In the present study, we selected the Posidonius FCC to explore the mineralogy, morphology and tectonic characteristics using remote sensing datasets. The Posidonius crater is vested with a w…
CHANG-ES XXIX: the sub-kpc nuclear bubble of NGC 4438
Bregman, Joel N.; Beck, Rainer; Wang, Q. Daniel +8 more
Active galactic nucleus (AGN) bubbles could play an important role in accelerating high-energy cosmic rays (CRs) and galactic feedback. Only in nearby galaxies could we have high enough angular resolution in multiwavelengths to study the sub-kpc environment of the AGN, where the bubbles are produced and strongly interact with the surrounding inter…
Deep Upper Limit on the Optical Emission during a Hard X-Ray Burst from the Magnetar SGR J1935+2154
Naletto, Giampiero; Burtovoi, Aleksandr; Mereghetti, Sandro +9 more
In 2021 September the magnetar SGR J1935+2154 entered a stage of burst/flaring activity in the hard X-ray band. On 2021 September 10, we observed SGR J1935+2154 with the fiber-fed fast optical photon counter IFI+Iqueye, mounted at the 1.22 m Galileo telescope in Asiago. During one of the IFI+Iqueye observing windows, a hard X-ray burst was detecte…
Ammonia characterisation of dense cores in the Rosette Molecular Cloud
Schneider, N.; Csengeri, T.; Motte, F. +5 more
Context. The Rosette molecular cloud complex is a well-known Galactic star-forming region with a morphology pointing towards triggered star formation. The distribution of its young stellar population and the gas properties point to the possibility that star formation is globally triggered in the region.
Aims: We focus on the characterisation …
Volume-limited sample of low-mass red giant stars, the progenitors of hot subdwarf stars. l. Sample selection and binary classification method
Uzundag, Murat; Jones, Matías I.; Bobrick, Alexey +3 more
Context. Current theory predicts that hot subdwarf binaries are produced from evolved low-mass binaries that have undergone mass transfer and drastic mass loss during either a common-envelope phase or a stable Roche-lobe overflow while on the red giant branch (RGB).
Aims: We perform a spectroscopic survey to find binary systems that include l…
Optical Cross-Match of SRG/eROSITA X-ray Sources Using the Deep Lockman Hole Survey as an Example
Gilfanov, M. R.; Belvedersky, M. I.; Bykov, S. D.
We present a method for the optical cross-match of sources detected in wide-field X-ray sky surveys. For this purpose, we have constructed and trained a neural network model to characterize the photometric attributes of the populations of optical counterparts of X-ray sources and optical field objects. The photometric information processing result…
Absolute parameters of four W UMa stars with extreme low mass ratios
Popov, Velimir A.; Petrov, Nikola I.
Photometric observations of four extreme low mass ratio W UMa binaries with wide total eclipses, and their absolute parameters are presented. The main results are as follows: (i) ASAS J015429+2042.8 is of A subtype while V755 Cep, VESPA V22 and GSC 02800-01387 are of W subtype; (ii) The mass ratios are close to the lower mass-ratio limit and can b…
Semi-supervised standardized detection of extrasolar planets
Deleuil, M.; Sulis, S.; Mary, D. +1 more
Context. The detection of small exoplanets with the radial velocity (RV) technique is limited by various poorly known noise sources of instrumental and stellar origin. As a consequence, current detection techniques often fail to provide reliable estimates of the significance levels of detection tests in terms of false-alarm rates or p-values.
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Evaluation of the Capability of ExoMars-TGO NOMAD Infrared Nadir Channel for Water Ice Clouds Detection on Mars
Daerden, Frank; Ristic, Bojan; Bellucci, Giancarlo +13 more
As part of the payload of the 2016 ExoMars Trace Gas Orbiter (TGO) mission, the Nadir and Occultation for MArs Discovery (NOMAD) suite instrument has been observing the Martian atmosphere since March 2018. NOMAD is mainly dedicated to the study of trace atmospheric species taking advantage of a high-spectral resolution. We demonstrate that when NO…
Seasonal southern circum-polar spots and araneiforms observed with the colour and stereo surface imaging system (CaSSIS)
Tornabene, Livio L.; Cremonese, Gabriele; Thomas, Nicolas +5 more
The southern polar area of Mars is home to various seasonal activity commonly explained by the Kieffer model. During southern spring, the ice covering the polar area sublimates and leaves distinct features (spiders, spots, fans) observable from orbit. The Colour and Stereo Surface Imaging System (CaSSIS) onboard the ExoMars Trace Gas Orbiter (TGO)…