Search Publications
Detection of wide binary and multiple nuclei of planetary nebulae using the Gaia DR3
Ali, A.; Khalil, J. M.; Mindil, A.
Context: this paper describes the detection of wide binary and multiple central stars (CSs) of Galactic planetary nebulae (PNe) using the most up-to-date data available from the Gaia Data Release 3 (Gaia DR3). Aims: the objective of this study is to benefit from the Gaia DR3's reliable measurements of parallax and proper motion to reveal the binar…
Geliosphere - parallel CPU and GPU based models of cosmic ray modulation in the heliosphere
Solanik, Michal; Bobík, Pavol; Genči, Ján
We present Geliosphere, a numerical model of the modulation of cosmic rays in the heliosphere. The current version of Geliosphere implements the stochastic differential equation method to solve Parker's equation. Sets of 1D and 2D models of Geliosphere solve Parker's equation in a backward-in-time manner for 2D models and in a backward-in-time and…
High-precision broadband linear polarimetry of early-type binaries. IV. The DH Cephei binary system in the open cluster of NGC 7380
Piirola, Vilppu; Berdyugin, Andrei V.; Sakanoi, Takeshi +2 more
Aims: DH Cephei is a well-known massive O+O-type binary system on the northern sky, situated at the center of young open cluster NGC 7380. Our high-precision multi-band polarimetry clearly reveals that variations of linear polarization in this system are synchronous with the phase of the orbital period. We used the observed variations of Stok…
Mesoscale Structure and Properties of the Terrestrial Magnetotail Plasma Sheet From the Magnetospheric Multiscale Mission
Vo, T.; Ergun, R. E.; Usanova, M. E. +1 more
Using Magnetospheric Multiscale mission (MMS) orbits in the Earth's magnetotail from 2017 to 2020, plasma conditions and the 3D spatial structure of inner-magnetotail plasma environments (with a focus on the plasma sheet (PS)) are studied with different approaches. Threshold conditions for distinguishing the PS, PS boundary layers, and lobes are d…
Photometry of the Four Anti-Galactocentric Old Open Clusters: Czernik 30, Berkeley 34, Berkeley 75, and Berkeley 76
Lee, Joon Hyeop; Kyeong, Jaemann; Kim, Sang Chul +2 more
We present a BVI photometric study of four old open clusters (OCs) in the the Milky Way, Czernik 30, Berkeley 34, Berkeley 75, and Berkeley 76 using the observation data obtained with the Small and Moderate Aperture Research Telescope System 1.0 m telescope at the Cerro Tololo Inter-American Observatory, Chile. These four OCs are located at the an…
The Long-term Spectral Changes of Eta Carinae: Are they Caused by a Dissipating Occulter as Indicated by CMFGEN Models?
Hamaguchi, Kenji; Corcoran, Michael F.; Russell, Christopher M. P. +23 more
Eta Carinae (η Car) exhibits a unique set of P Cygni profiles with both broad and narrow components. Over many decades, the spectrum has changed-there has been an increase in observed continuum fluxes and a decrease in Fe II and H I emission-line equivalent widths. The spectrum is evolving toward that of a P Cygni star such as P Cygni itself and H…
Constraint on the event rate of general relativistic instability supernovae from the early JWST deep field data
Harikane, Yuichi; Inoue, Akio K.; Moriya, Takashi J.
General relativistic instability supernovae (GRSNe) at 10 ≲ z ≲ 15 are predicted to be observed as red faint point sources, and they can be detected only in the reddest filters in James Webb Space Telescope (JWST)/NIRCam (F444W and F356W). They should be observed as persistent point sources with little flux variations for a couple of decades becau…
A Nearby Isolated Dwarf: Star Formation and Structure of ESO 006-001
Koribalski, Bärbel S.; Anand, Gagandeep S.; Tully, R. Brent +4 more
Observations with the Hubble Space Telescope unexpectedly revealed that the dwarf galaxy ESO 006-001 is a near neighbor to the Local Group at a distance of 2.70 ± 0.11 Mpc. The stellar population in the galaxy is well resolved into individual stars to a limit of M I ~ - 0.5 mag. The dominant population is older than 12 Gyr yet display…
Ionosphere of Mars during the consecutive solar minima 23/24 and 24/25 as seen by MARSIS-Mars Express
Witasse, Olivier; Sánchez-Cano, Beatriz; Kofman, Wlodek +4 more
The Mars' ionospheric behavior during two consecutive solar minima (23/24 and 24/25) is investigated with the same dataset. In particular, we use the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on board Mars Express to investigate the total electron content behavior of the whole atmosphere in relation to the solar irradian…
Confident detection of doubly ionized thorium in the extreme Ap star CPD-62° 2717
Nidever, David L.; Labadie-Bartz, Jonathan; Hasselquist, Sten +4 more
Despite the Universe containing primordial thorium (Th) of sufficient abundance to appear in stellar spectra, detection of Th has to date been tentative and based on just a few weak and blended lines. Here, we present convincing evidence not only for the first Th detection in a magnetic chemically peculiar Ap star but also for the first detection …