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Survey for Distant Solar Twins (SDST) - III. Identification of new solar twin and solar analogue stars
Murphy, Michael T.; Liu, Fan; Flynn, Chris +3 more
The Survey for Distant Solar Twins aims to find stars very similar to the Sun at distances of 1-$4\, {\rm kpc}$, several times more distant than any currently known solar twins and analogues. The goal is to identify the best stars with which to test whether the fine-structure constant, α, varies with dark matter density in our Galaxy. Here, we use…
Multifrequency Microwave Imaging of Weak Transients from the Quiet Solar Corona
Chen, Bin; Yu, Sijie; Mondal, Surajit
Understanding the dynamics of the quiet solar corona is important for answering key questions including the coronal heating problem. Multiple studies have suggested small-scale magnetic-reconnection events may play a crucial role. These reconnection events are expected to involve acceleration of electrons to suprathermal energies, which can then p…
Spectrum of the secondary component and new orbital elements of the massive triple star δ Ori A
Wade, G. A.; Lovekin, C. C.; Harmanec, P. +13 more
δ Orionis is the closest massive multiple stellar system and one of the brightest members of the Orion OB association. The primary (Aa1) is a unique evolved O star. In this work, we applied a two-step disentangling method to a series of spectra in the blue region (430-450 nm), and we detected spectral lines of the secondary (Aa2). For the first ti…
Particle monitoring capability of the Solar Orbiter Metis coronagraph through the increasing phase of solar cycle 25
Gissot, S.; Sasso, C.; Romoli, M. +26 more
Context. Galactic cosmic rays (GCRs) and solar particles with energies greater than tens of MeV penetrate spacecraft and instruments hosted aboard space missions. The Solar Orbiter Metis coronagraph is aimed at observing the solar corona in both visible (VL) and ultraviolet (UV) light. Particle tracks are observed in the Metis images of the corona…
Extended main-sequence turnoff and red clump in intermediate-age star clusters: A study of NGC 419
Dalessandro, E.; Massari, D.; Ferraro, F. R. +4 more
With the goal of untangling the origin of extended main-sequence turnoffs (eMSTOs) and extended red clumps (eRCs) in star clusters, in this work we present the study of the intermediate-age cluster NGC 419, situated along the Bridge of the Small Magellanic Cloud. To this aim, we analyzed multi-epoch, high angular resolution observations acquired w…
Chemical enrichment of ICM within the Ophiuchus cluster I: radial profiles
Fabian, A. C.; Pinto, C.; Eckert, D. +6 more
The analysis of the elemental abundances in galaxy clusters offers valuable insights into the formation and evolution of galaxies. In this study, we explore the chemical enrichment of the intracluster medium in the Ophiuchus cluster by utilizing XMM-Newton EPIC-pn observations. We explore the radial profiles of Si, S, Ar, Ca, and Fe. Due to the hi…
Whistler-mode waves in Mercury's magnetosphere observed by BepiColombo/Mio
Sahraoui, Fouad; Kasaba, Yasumasa; Omura, Yoshiharu +10 more
Whistler-mode chorus waves are natural electromagnetic emissions known to play a key role in electron acceleration and loss mechanisms via wave-particle interactions in planetary magnetospheres. Chorus waves have not yet been detected in Mercury's magnetosphere due to the lack of suitable instruments in the probes that previously visited the plane…
Cannonball or Bowling Ball: Proper Motion and Parallax for PSR J0002+6216
Frail, D. A.; Kerr, M.; Schinzel, F. K. +4 more
We report the results of careful astrometric measurements of the cannonball pulsar J0002+6216 carried out over 3 yr using the High Sensitivity Array. We significantly refine the proper motion to µ = 35.3 ± 0.6 mas yr-1 and place new constraints on the distance, with the overall effect of lowering the velocity and increasing the in…
The 14 Her Planetary System: Companion Masses and Architecture from Radial Velocities and Astrometry
McArthur, B. E.; Benedict, G. F.; Nelan, E. P. +1 more
We combine Hubble Space Telescope (HST) Fine Guidance Sensor, Hipparcos, and Gaia DR3 astrometric observations of the K0 V star 14 Her with the results of an analysis of extensive ground-based radial velocity data to determine perturbation orbits and masses for two previously known companions, 14 Her b and c. Radial velocities obtained with the Ho…
Morphology of the gas-rich debris disk around HD 121617 with SPHERE observations in polarized light
Kral, Quentin; Pinte, Christophe; Olofsson, Johan +7 more
Context. Debris disks are the signposts of collisionally eroding planetesimal circumstellar belts, whose study can put important constraints on the structure of extrasolar planetary systems. The best constraints on the morphology of such disks are often obtained from spatially resolved observations in scattered light. In this paper, we investigate…