Search Publications
Dynamical Masses for the Pleiades Binary System HII-2147
Torres, Guillermo; Crepp, Justin R.; Dupuy, Trent J. +3 more
We report our long-term spectroscopic monitoring of the Pleiades member HII-2147, which was previously spatially resolved at radio wavelengths in very long baseline interferometry (VLBI) observations. It has also been claimed to be a (presumably short-period) double-lined spectroscopic binary with relatively sharp lines, although no orbit has ever…
Constraining spatial pattern of early activity of comet 67P/C-G with 3D modelling of the MIRO observations
Keller, H. U.; Hartogh, P.; Rezac, L. +3 more
Our aim is to investigate early activity (2014 July) of 67P/C-G with 3D coma and radiative transfer modeling of Microwave Instrument on the Rosetta Orbiter (MIRO) measurements, accounting for nucleus shape, illumination, and orientation of the comet. We investigate MIRO line shape information for spatial distribution of water activity on the nucle…
Spectroscopic characterization of nine binary star systems as well as HIP 107136 and HIP 107533
Neuhäuser, R.; Mugrauer, M.; Bischoff, R. +6 more
We present the results of our second radial velocity (RV) monitoring campaign, carried out with the Échelle spectrograph FLECHAS at the University Observatory Jena in the course of the Großschwabhausen binary survey between December 2016 and June 2018. The aim of this project is to obtain precise RV measurements for spectroscopic binary stars in o…
Wide field-of-view study of the Eagle Nebula with the Fourier transform imaging spectrograph SITELLE at CFHT
Prunet, S.; McLeod, A. F.; Flagey, N. +1 more
Context. We present the very first wide-field, 11' by 11', optical spectral mapping of M 16, one of the most famous star-forming regions in the Galaxy. The data were acquired with the new imaging Fourier transform spectrograph SITELLE mounted on the Canada-France-Hawaii Telescope (CFHT). We obtained three spectral cubes with a resolving power of 1…
Pyroxene chemistry and crystallization history of basaltic units in the Mare Humorum on the nearside of the Moon: Implications for the volcanic history of the region
Rajesh, V. J.; Thesniya, P. M.
Mare basalts are volcanic features on the lunar surface and are vital for understanding the Moon's volcanic and thermal history. The present study investigates the mineralogy and chemical variations of the mare basaltic units in the Mare Humorum on the Moon's nearside using orbital remote sensing data from recent lunar exploration missions. The pr…
Unraveling the Nature of the Deeply Embedded Wolf-Rayet Star WR 121a
Pandey, J. C.; Arora, Bharti
An X-ray study of the deeply embedded Wolf-Rayet star WR 121a has been carried out using long-term (spanning over ∼12 yr) archival observations from Chandra and XMM-Newton. For the first time, a periodic variation of 4.1 days has been detected in the X-ray light curve of WR 121a. No companion is seen in a merged and exposure-corrected Chandra X-ra…
Lifting the dust veil from the globular cluster Palomar 2
Chies-Santos, Ana L.; Bonatto, Charles
This work employs high-quality Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) F606W and F814W photometry to correct for the differential reddening affecting the colour-magnitude diagram (CMD) of the poorly studied globular cluster (GC) Palomar 2. Differential reddening is taken into account by assuming that morphological difference…
Extended X-ray emission from the z = 4.26 radio galaxy 4C 63.20
Haardt, Francesco; Ciardi, Benedetta; Ghisellini, Gabriele +5 more
We report on deep Chandra X-ray Telescope imaging observations of 4C 63.20, one of the few known radio galaxies at z > 3.5. The X-ray counterpart is resolved into a core plus two off-nuclear sources that (combined) account for close to 30 per cent of the total X-ray flux. Their morphology and orientation are consistent with a diffuse, lobe-like…
Surprising Variability of the Planetary Nebula IC 4997 = QV Sge
Arkhipova, V. P.; Esipov, V. F.; Ikonnikova, N. P. +3 more
We present the results of a new epoch (2009-2019) of a long-term (50 years) photometric monitoring of the variable planetary nebula IC 4997 (QV Sge). The integral (star + nebula) $UBV$ light curves display a continuing brightening of $0\overset{m}{.}15$ in $V$, a slight rise (${<}0\overset{m}{.}1$) in $B$, and constancy in $U$. The $B-V$ color …
Discrete element modeling of boulder and cliff morphologies on comet 67P/Churyumov-Gerasimenko
Otto, K. A.; Sachse, M.; Kappel, D. +1 more
Context. Even after the Rosetta mission, some of the mechanical parameters of comet 67P/Churyumov-Gerasimenko's surface material are not yet well constrained. These parameters are needed to improve our understanding of cometary activity or for planning sample return missions.
Aims: We study some of the physical processes involved in the forma…