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The H I Gas Fraction Scaling Relation of the Green Pea Galaxies
Luo, A. -Li; Kong, Xiao; Zhao, Yong-Heng +3 more
Green Pea galaxies are compact galaxies with high star formation rates. However, limited samples of Green Pea galaxies have H I 21 cm measurements. Whether the H I gas fraction (f H I ≡ M H I/M ⋆) of Green Pea galaxies follows the existing scaling relations between the f H I and NUV-r color or linear com…
Testing Physical Scenarios for the Reflection Features of Type-1 AGNs using XMM-Newton and NuSTAR Simultaneous Observations
González-Martín, Omaira; Masegosa, Josefa; Victoria-Ceballos, César Ivan +3 more
Above ~3 keV, the X-ray spectrum of active galactic nuclei (AGNs) is characterized by the intrinsic continuum and Compton reflection features. For type-1 AGNs, several regions may contribute to the reflection. To investigate the nature of the reflecting medium, we perform a systematic analysis of the reflector using XMM-Newton and Nuclear Spectros…
Speed and Acceleration of Coronal Mass Ejections Associated with Sustained Gamma-Ray Emission Events Observed by Fermi/LAT
Gopalswamy, Nat; Akiyama, Sachiko; Yashiro, Seiji +2 more
The sustained gamma-ray emission (SGRE) from the Sun is a prolonged enhancement of >100 MeV gamma-ray emission that extends beyond the flare impulsive phase. The origin of the >300 MeV protons resulting in SGRE is debated, with both flares and shocks driven by coronal mass ejections (CMEs) being the suggested sites of proton acceleration. We…
Time-scale-dependent X-ray to UV time lags of NGC 4593 using high-intensity XMM-Newton observations with Swift and AstroSat
Dewangan, Gulab C.; Singh, Kulinder Pal; McHardy, Ian M. +6 more
We present a 140 ks observation of NGC 4593 with XMM-Newton providing simultaneous and continuous pn X-ray and OM UV (UVW1 2910 Å) light curves, which sample short-time-scale variations better than previous observations. These observations were simultaneous with 22 d of Swift X-ray and UV/optical monitoring reported previously, and 4 d of AstroSat…
Lamp-post with an outflow and the hard state of Cyg X-1
Szanecki, Michał; Niedźwiecki, Andrzej; Klepczarek, Łukasz
Relativistic reflection observed in the hard states of accreting black holes (BH) often shows a weak amplitude relative to the main Comptonization component, which may result from either a disc truncation or a non-isotropy of the X-ray source, e.g. due to a motion away from the reflector. We investigate here the latter case, assuming that the X-ra…
Precise Distance Measurement for a Near-Earth Asteroid by the Refined Rotational Reflex Velocity Method
Lin, F. R.; Peng, Q. Y.; Guo, B. F. +1 more
The rotational reflex velocity (RRV) method was proposed by Heinze and Metchev in 2015 and was used to measure the distances of main-belt asteroids (MBAs). Later, Lin et al. generalized this method using spherical astronomy in 2016. The method measures the distances of MBAs using the observations from a single ground-based telescope over two night…
PCAT-DE: Reconstructing Pointlike and Diffuse Signals in Astronomical Images Using Spatial and Spectral Information
Daylan, Tansu; Zemcov, Michael; Sayers, Jack +5 more
Observational data from astronomical imaging surveys contain information about a variety of source populations and environments, and their complexity will increase substantially as telescopes become more sensitive. Even for existing observations, measuring the correlations between pointlike and diffuse emission can be crucial to correctly inferrin…
Structure of the W3A Low-density Foreground Region
Seo, Youngmin; Goldsmith, Paul. F.; Stutzki, Jürgen +5 more
We present analysis of [O I] 63 µm and CO J = 5 - 4 and 8 - 7 multiposition data in the W3A region and use it to develop a model for the extended low-density foreground gas that produces absorption features in the [O I] and J = 5 - 4 CO lines. We employ the extinction to the exciting stars of the background H II region to constrain the total…
Prediction of Proton Pressure in the Outer Part of the Inner Magnetosphere Using Machine Learning
Mouikis, C. G.; Kronberg, E. A.; Li, S. Y. +3 more
The information on plasma pressure in the outer part of the inner magnetosphere is important for simulations of the inner magnetosphere and a better understanding of its dynamics. Based on 17-year observations from both Cluster Ion Spectrometry and Research with Adaptive Particle Imaging Detector instruments onboard the Cluster mission, we used ma…
Astrophysical Studies of 9 Unstudied Open Star Clusters Using GAIA DR3
Tadross, A. L.; Badawy, W. A.; Hendy, Y. H. M. +2 more
Using the Gaia DR3 data sets, this work gives an analysis of nine open clusters: Dolidze 25, Kronberger 13, Kronberger 18, Majaess 99, NGC 7795, Ruprecht 139, Teutsch 55, S1, and FSR 0596, which are close to the Galactic plane of the Milky Way. The number of probable cluster members is found to be 81, 77, 120, 155, 108, 110, 160, and 116 respectiv…