Search Publications
On the source region and orientations of nightside auroral arcs
Sergeev, V.; Bondareva, T.; Gilles, D. +1 more
Using large data base of stable auroral arcs observed at Gillam we identified those passes of POES spacecraft which were magnetically conjugate to these arcs. We studied statistically arc locations with respect to the energetic particle isotropy boundaries (IBs), which are the well-known markers of the magnetotail regions. In the dusk and night se…
A KELT-TESS Eclipsing Binary in a Young Triple System Associated with the Local "Stellar String" Theia 301
Cunningham, Joni-Marie C.; Feliz, Dax L.; Dixon, Don M. +10 more
HD 54236 is a nearby, wide common-proper-motion visual pair that has been previously identified as likely being very young by virtue of strong X-ray emission and lithium absorption. Here, we report the discovery that the brighter member of the wide pair, HD 54236A, is itself an eclipsing binary (EB), comprising two near-equal solar-mass stars on a…
Identification of temperature anomaly RR Lyrae stars in LAMOST survey, misclassification and binarities
Li, Lin-Jia; Qian, Sheng-Bang; Zhu, Li-Ying +2 more
RR Lyrae stars, a well-known type of pulsating variable stars, have been known about for more than a century. A large amount of photometric data on RR Lyrae stars has been accumulated by space- and ground-based sky surveys, but the spectral data are relatively poor. Fortunately, the LAMOST sky survey project provides an opportunity to view them fr…
Open-field Coronal Structures Neighbouring the Sunspot of AR 8535
Vrublevskis, A.; Ryabov, B. I.
We make use of the Potential Field Source Surface (PFSS) model and reveal new details in the strong fields of the dominant sunspot of the active region (AR) 8535. Due to its importance in determining the field line connectivity and topology with resulting consequences for both plasma confinement and dynamics we construct the global magnetic fields…
Spin pairs in the Koronis asteroid family
Carruba, V.; Aljbaae, S.; Martins, B. +4 more
Asteroid groups may either form because of collisions or the rotational failure of a parent body. Collisional asteroid families tend to be more spread in proper element domains, while young spin clusters are usually much more compact. Recently, it has been shown that young spin clusters may form at higher rates in extremely young asteroid families…
The ionosphere of Venus: Strongest control by photo-chemical-equilibrium in the solar system, with implications for exospheric temperatures
Pätzold, M.; Häusler, B.; Tellmann, S. +5 more
Profiles of electron density versus height obtained by the radio occultation experiment on Venus Express provide an observational data base suitable for semi-empirical modeling. The basic equations of photo-chemical-equilibrium (PCE) theory can be applied to the altitude range 100-170 km of Venus' ionosphere (Peter et al., 2014). Within that domai…
U, B, V, Rc, Ic Photometric Observations of the Dwarf Nova DX Andromedae During the Years 2018-2019
Ciprini, S.; Spogli, C.; Rocchi, G. +1 more
In this paper we present U, B,V, Rc, Ic photometric observations of the dwarf nova DX Andromedae made in the years 2018-2019 at the private Rocchi observatory located in Spello (Umbria). We observed the variable for 86 nights in B, V, Rc, Ic photometric filters. We detected an outburst of this dwarf nova. We summarize the significant variations in…
Accretion in low-mass members of the Orion Nebula Cluster with young transition disks
Alencar, S. H. P.; Gameiro, J. F.; Lima, J. J. G. +3 more
Context. Although the Orion Nebula Cluster is one of the most studied clusters in the solar neighborhood, the evolution of the very low-mass members (M* < 0.25 M⊙) has not been fully addressed due to their faintness.
Aims: Our goal is to verify if some young and very low-mass objects in the Orion Nebula Cluster show e…
Radar Sounding of Subsurface Structure in Eastern Coprates and Capri Chasmata, Mars
Kasaba, Yasumasa; Kumamoto, Atsushi; Oura, Aina +5 more
We surveyed the subsurface structure in eastern Coprates and Capri Chasmata in the equatorial region using high-resolution visible images, digital terrain models, and radar sounding data. We identified subsurface reflectors in four areas of the chasmata. At the stratigraphic exposure on the chasmata walls, the corresponding depth of the reflector …
The ionic composition of the local absorber towards 3C 273
Behar, Ehud; Peretz, Uria; Gissis, Itay
Hot ionized gas is observed in the local vicinity of our galaxy through spectral absorption features. The most common hypothesis is that this gas forms a halo surrounding our Milky Way, in collisional ionization equilibrium. In this paper, we investigate the elemental abundance of this hot and ionized local gas. We use a 2.4 Ms stacked X-ray spect…