Search Publications
Outgassing-induced acceleration of comet 67P/Churyumov-Gerasimenko
Kramer, T.; Läuter, M.
Context. Cometary activity affects the orbital motion and rotation state through sublimation-induced forces. The availability of precise rotation-axis orientation and position data from the Rosetta mission allows us to accurately determine the outgassing of comet Churyumov-Gerasimenko/67P (67P).
Aims: We derived the observed non-gravitational…
Interplay between pulsation, mass loss, and third dredge-up: More about Miras with and without technetium
Bernhard, K.; Cristallo, S.; McDonald, I. +2 more
Context. We follow-up on a previous finding that AGB Mira variables containing the third dredge-up indicator technetium (Tc) in their atmosphere form a different sequence of K - [22] colour as a function of pulsation period than Miras without Tc. A near- to mid-infrared colour such as K - [22] is a good probe for the dust mass-loss rate of the sta…
Herschel map of Saturn's stratospheric water, delivered by the plumes of Enceladus
Fletcher, L. N.; Hartogh, P.; Lellouch, E. +13 more
Context. The origin of water in the stratospheres of giant planets has been an outstanding question ever since its first detection by the Infrared Space Observatory some 20 years ago. Water can originate from interplanetary dust particles, icy rings and satellites, and large comet impacts. Analyses of Herschel Space Observatory observations have p…
Stellar population astrophysics (SPA) with the TNG. Characterization of the young open cluster ASCC 123
Vallenari, A.; Sordo, R.; Bragaglia, A. +10 more
Star clusters are crucial to understanding stellar and Galactic evolution. ASCC 123 is a little-studied, nearby, and very sparse open cluster. We performed the first high-resolution spectroscopic study of this cluster in the framework of the Stellar Population Astrophysics (SPA) project with GIARPS at the TNG. We observed 17 stars, 5 of which turn…
Horizontal branch morphology: A new photometric parametrization
Salaris, M.; Fontana, A.; Castellani, M. +8 more
Context. Theory and observations indicate that the distribution of stars along the horizontal branch of Galactic globular clusters mainly depends on the metal content. However, the existence of globular clusters with similar metal content and absolute age but different horizontal branch morphologies, suggests the presence of another parameter affe…
Projection effects in galaxy cluster samples: insights from X-ray redshifts
Lovisari, L.; Pacaud, F.; Ramos-Ceja, M. E. +3 more
Presently, the largest sample of galaxy clusters selected in X-rays comes from the ROSAT All-Sky Survey (RASS). Although there have been many interesting clusters discovered with the RASS data, the broad point spread function of the ROSAT satellite limits the attainable amount of spatial information for the detected objects. This leads to the disc…
Comet 67P/Churyumov-Gerasimenko rotation changes derived from sublimation-induced torques
Jorda, L.; Kührt, E.; Keller, H. U. +3 more
Context. The change in rotation period and the orientation of the rotation axis of comet 67P/Churyumov-Gerasimenko (67P) can be deduced with high precision from images taken by the scientific imaging instruments on board the Rosetta mission. Non-gravitational forces are a natural explanation for these data.
Aims: We describe observed changes …
Determining the mass of the planetary candidate HD 114762 b using Gaia
Kiefer, Flavien
The first planetary candidate discovered by Latham et al. (1989, Nature, 339, 38) with radial velocities around a solar-like star other than the Sun, HD 114762 b, was detected with a minimum mass of 11 MJ. The small v sin i ∼ 0 km s-1 that is otherwise measured by spectral analysis indicated that this companion of a late-F su…
Probing X-ray emission in different modes of PSR J1023+0038 with a radio pulsar scenario
Campana, S.; Torres, D. F.; Papitto, A. +3 more
Transitional pulsars provide us with a unique laboratory to study the physics of accretion onto a magnetic neutron star. PSR J1023+0038 (J1023) is the best studied of this class. We investigate the X-ray spectral properties of J1023 in the framework of a working radio pulsar during the active state. We modelled the X-ray spectra in three modes (lo…
Variability of young stellar objects in the star-forming region Pelican Nebula
Chen, W. P.; Herczeg, G. J.; Bhardwaj, A. +2 more
Context. Pre-main-sequence variability characteristics can be used to probe the physical processes leading to the formation and initial evolution of both stars and planets.
Aims: The photometric variability of pre-main-sequence stars is studied at optical wavelengths to explore star-disk interactions, accretion, spots, and other physical mech…