Search Publications
Globular Cluster as Indicators of Galactic Evolution
Pilipenko, S. V.; Arkelyan, N. R.
We have studied the system of globular clusters (GCs) that formed in other galaxies and eventually accreted onto the Milky Way. Thus, the samples of GCs belonging to different tidal streams, obtained on the basis of the latest data from the GAIA observatory, were taken from the literature. We measured the anisotropy of the distribution of these GC…
Catalogs of Solar Proton Events as a Tool for Studying Space Weather
Vlasova, N. A.; Bazilevskaya, G. A.; Ginzburg, E. A. +8 more
Distinguishing features of a series of solar proton event (SPE) catalogs for the 20th-24th cycles of solar activity are described. The results of a comparative analysis of the 23rd and 24th cycles of solar activity performed according to the data of a series of SPE catalogs are presented. The opportunities provided by SPE catalogs for studying spa…
Multiwavelength Observations of MWC 297: Constraints on Disk Inclination and Mass Outflow
Vacca, William D.; Sandell, Göran
MWC 297 is a young, early-type star driving an ionized outflow and surrounded by warm, entrained dust. Previous analyses of near- and mid-IR interferometric images suggest that the emission at these wavelengths arises from a compact accretion disk with a moderate (i < 40°) inclination. We have obtained 5-40 µm images of MWC 297 with FORCA…
ArTéMiS imaging of the filamentary infrared dark clouds G1.75-0.08 and G11.36+0.80: Dust-based physical properties of the clouds and their clumps
André, Ph.; Miettinen, O.; Mattern, M.
Context. Filamentary infrared dark clouds (IRDCs) are a useful class of interstellar clouds for studying the cloud fragmentation mechanisms on different spatial scales. Determination of the physical properties of the substructures in IRDCs can also provide useful constraints on the initial conditions and early stages of star formation, including t…
Orbital period changes in IO Cep, IM Cep and TX Ari: Path to masses of distant components
Bakış, V.; Eker, Z.; Bakış, H. +7 more
Three Algol-type binary systems (IO Cep, IM Cep and TX Ari) showing cyclic orbital period changes are studied. The combination of time of minimum data from the ground-based observations together with high precision photometric data from the TESS satellite enabled us to estimate the basic light curve elements of binary systems and mass functions fo…
A Parametric Study of Performance of Two Solar Wind Velocity Forecasting Models During 2006-2011
Srivastava, Nandita; Kumar, Sandeep
There is an increasing need for the development of a robust space weather forecasting framework. State-of-the-art MHD space weather forecasting frameworks are based upon the Potential Field Source Surface (PFSS) and Schatten Current Sheet (SCS) extrapolation models for the magnetic field using synoptic magnetograms. These models create a solar win…
Plasma Diagnostics in the Era of Integral Field Spectroscopy
Ueta, Toshiya
To understand the physical conditions of various gaseous systems, plasma diagnostics must be performed properly. To that end, it is equally important to have extinction correction performed properly, even before performing plasma diagnostics. This means that the physical conditions of the target sources—the very quantities to be derived via plasma…
Complementary astrometry of Cassini Imaging Science Subsystem images of Phoebe
Li, Y.; Cooper, N. J.; Lainey, V. +5 more
Phoebe is the only major satellite of Saturn with a retrograde orbit. The Cassini Imaging Science Subsystem (ISS) took a lot of Phoebe images between 2004 and 2017, but only a selection of them has been reduced. In this paper, we reduced the remaining ISS images of Phoebe. In the reduction, the Gaia EDR3 catalogue was used to provide the reference…
Likely optical counterpart of the cool middle-aged pulsar J1957+5033
Geier, S.; Zharikov, S. V.; Karpova, A. V. +6 more
The 840-kyr-old pulsar PSR J1957+5033, detected so far only in γ- and X-rays, is a nearby and rather cool neutron star with a temperature of 0.2-0.3 MK, a distance of $\lesssim 1$kpc, and a small colour reddening excess E(B - V) ≈ 0.03. These properties make it an ideal candidate to detect in the optical to get additional constraints on its parame…
Near-IR narrow-band imaging with CIRCE at the Gran Telescopio Canarias: Searching for Lyα-emitters at z ∼ 9.3
Mas-Hesse, J. M.; Herrero, A.; Marín-Franch, A. +8 more
Context. Identifying very high-redshift galaxies is crucial for understanding the formation and evolution of galaxies. However, many questions still remain, and the uncertainty on the epoch of reionization is large. In this approach, some models allow a double-reionization scenario, although the number of confirmed detections at very high z is sti…