Search Publications
Peekaboo: the extremely metal poor dwarf galaxy HIPASS J1131-31
Koribalski, B. S.; Karachentsev, I. D.; Anand, G. S. +3 more
The dwarf irregular galaxy HIPASS J1131-31 was discovered as a source of HI emission at low redshift in such close proximity of a bright star that we call it Peekaboo. The galaxy resolves into stars in images with Hubble Space Telescope, leading to a distance estimate of 6.8 ± 0.7 Mpc. Spectral optical observations with the Southern African Large …
The GAPS programme at TNG. XLVI. Deep search for low-mass planets in late-dwarf systems hosting cold Jupiters
Pagano, I.; Poretti, E.; Rainer, M. +30 more
Context. With the growth of comparative exoplanetology, it is increasingly clear that the relationship between inner and outer planets plays a key role in unveiling the mechanisms governing formation and evolution models. For this reason, it is important to probe the inner region of systems hosting long-period giants in search of undetected lower …
Search for planets around stars with wide brown dwarfs
Béjar, V. J. S.; Zapatero Osorio, M. R.; Grundahl, F. +6 more
Aims: This work aims to better understand the role of wide brown dwarf companions in planetary systems.
Methods: We obtained high-resolution spectra of six bright stars with co-moving wide substellar companions with the high-resolution SONG, CARMENES, and STELLA spectrographs. We used these spectra to derive radial velocities together wi…
The Dynamic Evolution of Multipoint Interplanetary Coronal Mass Ejections Observed with BepiColombo, Tianwen-1, and MAVEN
Zhang, Zhiyong; Zhang, Tielong; Su, Zhenpeng +28 more
We present two multipoint interplanetary coronal mass ejections (ICMEs) detected by the Tianwen-1 and Mars Atmosphere and Volatile Evolution spacecraft at Mars and the BepiColombo (0.56 au ~0.67 au) upstream of Mars from 2021 December 5 to 31. This is the first time that BepiColombo is used as an upstream solar wind monitor ahead of Mars and that …
Improving Distances to Binary Millisecond Pulsars with Gaia
Bedell, Megan; Spergel, David N.; Moran, Abigail +2 more
Pulsar distances are notoriously difficult to measure, and play an important role in many fundamental physics experiments, such as pulsar timing arrays. Here, we perform a cross-match between International PTA pulsars (IPTA) and Gaia's Data Release 2 (DR2) and Data Release 3 (DR3). We then combine the IPTA pulsar's parallax with its binary compani…
Constraining Fundamental Parameters in Modified Gravity Using Gaia-DR2 Massive White Dwarf Observations
Uniyal, Akhil; Kalita, Surajit
Various experiments and observations have led researchers to suggest different bounds on fundamental constants like the fine-structure constant and the proton-to-electron mass ratio. These bounds differ mostly due to the energy scale of the systems where the experiments are performed. In this article, we obtain bounds on these parameters in the mo…
The Purport of Space Telescopes in Supernova Research
Vinkó, József; Könyves-Tóth, Réka; Szalai, Tamás
The violent stellar explosions known as supernovae have received especially strong attention in both the research community and the general public recently. With the advent of space telescopes, the study of these extraordinary events has switched gears and it has become one of the leading fields in modern astrophysics. In this paper, we review som…
Reaching the boundary between stellar kinematic groups and very wide binaries. IV. The widest Washington Double Star systems with ρ ≥ 1000 arcsec in Gaia DR3
Caballero, J. A.; Cortés-Contreras, M.; González-Payo, J.
Aims: With the latest Gaia DR3 data, we analyse the widest pairs in the Washington Double Star (WDS) catalogue with angular separations, ρ, greater than 1000 arcsec.
Methods: We confirmed the pairs' membership to stellar systems based on common proper motions, parallaxes, and (when available) radial velocities, together with the locii of…
Ultracool dwarfs candidates based on 6 yr of the Dark Energy Survey data
Bacon, D.; Bechtol, K.; Smith, M. +58 more
We present a sample of 19 583 ultracool dwarf candidates brighter than z ≤23 selected from the Dark Energy Survey DR2 coadd data matched to VHS DR6, VIKING DR5, and AllWISE covering ~ 480 deg2. The ultracool candidates were first pre-selected based on their (i-z), (z-Y), and (Y-J) colours. They were further classified using a method tha…
The Period Distribution of Hot Jupiters Is Not Dependent on Host Star Metallicity
Winn, Joshua N.; Yee, Samuel W.
The probability that a Sun-like star has a close-orbiting giant planet (period ≲1 yr) increases with stellar metallicity. Previous work provided evidence that the period distribution of close-orbiting giant planets is also linked to metallicity, hinting that there two formation/evolution pathways for such objects, one of which is more probable in …