Search Publications
Missions
Journals
Publication Years
Follow-up on three poorly studied AM CVn stars
Reichart, D. E.; Hermes, J. J.; Dhillon, V. S. +12 more
We report follow-up observations of three poorly studied AM CVn-type binaries: CRTS CSS150211 J091017-200813, NSV 1440, and SDSS J183131.63+420220.2. Analysing time-series photometry obtained with a range of ground-based facilities as well as with the Transiting Exoplanet Survey Satellite (TESS), we determine the superhump period of CRTS J0910-200…
Using Gaia and synthetic photometry for the absolute flux calibration of planetary cameras: The case of BepiColombo/SIMBIO-SYS
Cremonese, G.; Munaretto, G.; Sordo, R. +6 more
Context. The absolute flux calibration of a planetary camera is pivotal for a quantitative analysis of the brightness that is reflected by a celestial body to a) characterise its microphysical properties, b) analyse changes caused by exogenic or endogenic activity, and c) produce high-quality image mosaics to understand the geology of the body. Th…
Polarization and Interstellar Extinction Towards the Open Star Cluster NGC 6633
Topasna, G. A.; Kaltcheva, N. T.; Kirk, N. E.
We present optical polarization data of 110 stars in the direction of NGC 6633. From multi-wavelength BVRI measurements of 64 of these stars we obtained a wavelength of maximum polarization that yielded an estimate of total-to-selective extinction ratio RV = 3.18 ± 0.04 over the observed region. The distribution of the polarization posi…
Simulations for In-Flight Stellar Calibration Aimed at Monitoring Space Instruments' Optical Performance: Simulations for In-Flight Stellar Calibration Aimed at Monitoring...
Da Deppo, Vania; Frassetto, Fabio; Zuppella, Paola +3 more
Stellar in-flight calibrations have a relevant impact on the capability of space optical instruments, such as telescopes or cameras, to provide reliable scientific products, i.e., accurately calibrated data. Indeed, by using the in-flight star images, instrument optical performance can be checked and compared with the on-ground measurements. The a…
Energy injection, transport, and dissipation in Earth's magnetosphere
Cao, Jinbin; Fu, Huishan
The Earth's magnetosphere is a region occupied by many artificial satellites, and also is a region that spacecraft must cruise during the deep-space exploration. In this sense, the Earth's magnetosphere is closely related to human activity and is a candidate for us to expand our living space. Generally, the Earth's magnetosphere can preclude most …
A Machine Learning Approach to Predicting SEP Proton Intensity and Events Using Time Series of Relativistic Electron Measurements
Zhang, Ming; Zhao, Lulu; Torres, Jesse +1 more
Solar energetic particles (SEP) can cause severe damage to astronauts and sensitive equipment in space, and can disrupt communications on Earth. A lack of thorough understanding the eruption processes of solar activities and the subsequent acceleration and transport processes of energetic particles makes it difficult for physics-based models to fo…
Timing and spectral studies of the Be/X-ray binary EXO 2030+375 using Insight-HXMT observations
Bu, Qing-Cui; Santangelo, Andrea; Ji, Long +5 more
We report the results of a X-ray spectral and timing analysis of the high mass X-ray binary EXO 2030+375 during the 2021 type-II outburst based on Insight-HXMT observations. We confirm that pulsations can be detected in the energy band of 1‑150 keV. The pulse profile shows both energy and luminosity dependence and variability. We observed transiti…
TOI-2458 b: A mini-Neptune consistent with in situ hot Jupiter formation
Bieryla, Allyson; Latham, David W.; Cochran, William D. +33 more
We report on the discovery and spectroscopic confirmation of TOI-2458 b, a transiting mini-Neptune around an F-type star leaving the main-sequence with a mass of M★ = 1.05 ± 0.03 M⊙, a radius of R★ = 1.31 ± 0.03 R⊙, an effective temperature of Teff = 6005 ± 50 K, and a metallicity of ‑0.10 ± 0…
Observations of the Ultraviolet-bright Star III-60 in the Globular Cluster NGC 6723
Dixon, William V.
We have analyzed archival far-ultraviolet spectra of the UV-bright star III-60 in the globular cluster NGC 6723 obtained with the Far Ultraviolet Spectroscopic Explorer and the Cosmic Origins Spectrograph. We find that the star's photospheric parameters (effective temperature Teff = 44,800 ± 1200 K, surface gravity
The elderly among the oldest: new evidence for extremely metal-poor RR Lyrae stars
Marconi, M.; Fabrizio, M.; D'Orazi, V. +21 more
We performed a detailed spectroscopic analysis of three extremely metal-poor RR Lyrae stars, exploring uncharted territories at these low metallicities for this class of stars. Using high-resolution spectra acquired with HARPS-N at TNG, UVES at VLT, and PEPSI at LBT, and employing Non-Local Thermodynamic Equilibrium (NLTE) spectral synthesis calcu…