Search Publications
Spectrum of imbalanced Alfvénic turbulence at ion-kinetic scales in the solar wind
Voitenko, Y. M.; Gogoberidze, G.
Using a semi-phenomenological model of the imbalanced Alfvénic turbulence, we study the turbulence transition from magnetohydrodynamic to sub-ion kinetic scales in the conditions typical for the fast solar wind. We show that the transition takes place in a wide wave number interval where the energy spectrum does not follow any power law. For large…
HD 54361: evidence for the status of a low mass TP-AGB star
Schmidt, M.; Sperauskas, J.; Začs, L. +3 more
The mass of the cool carbon star HD 54361 was suspected to be high, assuming the membership in the stellar association CMa OB1, in conflict with the theory of stellar evolution. The Gaia parallax and a high-resolution spectrum in the wavelength region from about 4800 to 6900 Å was employed in order to update the distance, atmospheric parameters an…
Exoplanet system Kepler-2 with comparisons to Kepler-1 and 13
Budding, Edwin; Rhodes, Michael D.; Banks, Timothy S. +1 more
We have carried out an intensive study of photometric (Kepler Mission) and spectroscopic data on the system Kepler-2 (HAT-P-7A) using the dedicated software WINFITTER 6.4. The mean individual data-point error of the normalized flux values for this system is 0.00015, leading to the model's specification for the mean reference flux to an accuracy of…
Measuring the Hubble constant and spatial curvature from supernova apparent magnitude, baryon acoustic oscillation, and Hubble parameter data
Park, Chan-Gyung; Ratra, Bharat
Cosmic microwave background (CMB) anisotropy (spatial inhomogeneity) data provide the tightest constraints on the Hubble constant, matter density, spatial curvature, and dark energy dynamics. Other data, sensitive to the evolution of only the spatially homogeneous part of the cosmological model, such as Type Ia supernova apparent magnitude, baryon…
Observational constraints on the tilted flat-XCDM and the untilted nonflat XCDM dynamical dark energy inflation parameterizations
Park, Chan-Gyung; Ratra, Bharat
We constrain tilted spatially-flat and untilted nonflat XCDM dynamical dark energy inflation parameterizations using Planck 2015 cosmic microwave background (CMB) anisotropy data and recent baryonic acoustic oscillations distance measurements, Type Ia supernovae data, Hubble parameter observations, and growth rate measurements. Inclusion of the fo…
CCD UBV photometric and Gaia astrometric study of eight open clusters—ASCC 115, Collinder 421, NGC 6793, NGC 7031, NGC 7039, NGC 7086, Roslund 1 and Stock 21
Paunzen, E.; Güver, T.; Bilir, S. +8 more
In this study, we carried out CCD UBV photometry of eight open clusters, ASCC 115, Collinder 421, NGC 6793, NGC 7031, NGC 7039, NGC 7086, Roslund 1, Stock 21, and determined their reddening, metallicity, distance, age, and mass functions. We used new Gaia Data Release 2 (DR2) astrometric data to separate cluster member stars from the field stars a…
Radio emission from interstellar shocks: Young type Ia supernova remnants and the case of N 103B in the Large Magellanic Cloud
Haberl, F.; Filipović, M. D.; Rowell, G. +19 more
We investigate young type Ia supernova remnants (SNRs) in our Galaxy and neighbouring galaxies in order to understand their properties and early stage of their evolution. Here we present a radio continuum study based on new and archival data from the Australia Telescope Compact Array (ATCA) towards N 103B, a young (≤1000 yrs) spectroscopically con…
A young multipolar planetary nebula in the making—IRAS 21282+5050
Zhang, Yong; Kwok, Sun; Hsia, Chih-Hao +1 more
We present high-angular-resolution Hubble Space Telescope (HST) optical and near-infrared imaging of the compact planetary nebula (PN) IRAS 21282+5050. Optical images of this object reveal several complex morphological structures including three pairs of bipolar lobes and an elliptical shell lying close to the plane of the sky. From near-infrared …
Implication of kinetic Alfvén waves to magnetic field turbulence spectra: Earth's magnetosheath
Khodachenko, M. L.; Kumar, S.; Echim, M. +5 more
In the present paper, we investigate the power-law behaviour of the magnetic field spectra in the Earth's magnetosheath region using Cluster spacecraft data under solar minimum condition. The power spectral density of the magnetic field data and spectral slopes at various frequencies are analysed. Propagation angle,
The analysis of effective galaxies number count for Chinese Space Station Optical Survey (CSS-OS) by image simulation
Zhang, Xin; Meng, Xianmin; Cao, Li
The Chinese Space Station Optical Survey (CSS-OS) is a mission to explore the vast universe. This mission will equip a 2-meter space telescope to perform a multi-band NUV-optical large area survey (over 40