Search Publications
The miniJPAS Survey: Detection of the double-core Lyα morphology for two high-redshift QSOs
Diego, J. M.; Hernán-Caballero, A.; Mendes de Oliveira, C. +30 more
Context. The Lyα emission is an important tracer of neutral gas in a circum-galactic medium (CGM) around high-z quasi-stellar objects (QSOs). The origin of Lyα emission around QSOs is still under debate, bringing on significant implications for galaxy formation and evolution.
Aims: In this paper, we study Lyα nebulae around two high redshift …
X-ray spectral-timing variability of 1A 0535+262 during the 2020 giant outburst
Zhang, S.; Reig, P.; Ma, R. C. +3 more
Context. The Be/X-ray binary 1A 0535+262 underwent a giant X-ray outburst in November 2020, peaking at ∼1 × 1038 erg s−1 (1-100 keV, 1.8 kpc), the brightest outburst recorded for this source so far. The source was monitored over two orders of magnitude in luminosity with Insight-HXMT, which allowed us to probe the X-ray varia…
First evidence of a stripped star cluster from the Small Magellanic Cloud
Piatti, Andrés E.; Lucchini, Scott
We present results on the recently discovered stellar system YMCA-1, for which physical nature and belonging to any of the Magellanic System galaxies have been irresolutely analysed. We used SMASH and Gaia Early Data Release 3 data sets to conclude that we are dealing with a small star cluster. Its reddening-free, field star decontaminated colour-…
Study of Slow-Mode Shock Formation and Particle Acceleration in the Symmetric Magnetic Reconnection Based on Hybrid Simulations
Seki, K.; Amano, T.; Walia, N. K.
The structure of the magnetic reconnection region and the acceleration mechanism of particles as they traverse from upstream into the reconnection exhaust are explored using 2.5D hybrid simulations. The reconnection boundary was analyzed using the Rankine-Hugoniot conditions and the six specific conditions for slow-mode shocks. We observe that the…
A Review of Cluster Wideband Data Multi-Spacecraft Observations of Auroral Kilometric Radiation
Pickett, J. S.; Yearby, K. H.
We review important advances in the understanding of auroral kilometric radiation (AKR) resulting from observations by the Wideband Data instruments on the four Cluster spacecraft. AKR is an intense radio emission originating in the Earth's auroral regions with frequencies typically in the range 50-700 kHz, usually observed from space. It is now w…
The Smallest Scale of Hierarchy Survey (SSH) - II. Extended star formation and bar-like features in the dwarf galaxy NGC 3741: recent merger or ongoing gas accretion?
Bacchini, C.; Cignoni, M.; Tosi, M. +12 more
Using Large Binocular Telescope deep imaging data from the Smallest Scale of Hierarchy Survey (SSH) and archival Hubble Space Telescope data, we reveal the presence of two elongated stellar features contiguous to a bar-like stellar structure in the inner regions of the dwarf irregular galaxy NGC 3741. These structures are dominated by stars younge…
South Pole Station Ground-Based and Cluster Satellite Measurements of Leaked and Escaping Auroral Kilometric Radiation
Yearby, Keith; Pickett, Jolene S.; LaBelle, James
Previous work suggests that Auroral Kilometric Radiation (AKR) leaks to low altitudes. To investigate this phenomenon, wideband wave measurements have been conducted simultaneously at South Pole, Antarctica, and at the Cluster satellites, during 35 intervals in 2018-2020. Leaked AKR is observed ∼5% of the time at South Pole and escaping AKR ∼31% o…
Fitting XMM-Newton observations of the AXP 1RXS J170849.0−400910 with four magnetar surface emission models, and predictions for X-ray polarization observations with IXPE
Mereghetti, Sandro; Turolla, Roberto; Rigoselli, Michela +2 more
Context. Phase-resolved spectral and spectropolarimetric X-ray observations of magnetars present us with the opportunity to test models of the origin of the X-ray emission from these objects, and to constrain the properties of the neutron star surface and atmosphere.
Aims: Our first aim is to use archival XMM-Newton observations of the magnet…
A 4 kpc Molecular Gas Lane in Cygnus A
Nyland, Kristina; Decarli, Roberto; Perley, Daniel A. +4 more
We present the discovery of a 4 kpc molecular gas lane in the Cygnus A host galaxy, using Atacama Large Millimeter/submillimeter Array CO 2-1 observations. The gas lane is oriented roughly perpendicular to the projected radio jet axis. The CO emission generally follows the clumpy dust lanes seen in Hubble Space Telescope I-band images. The total m…
Causal Interaction between the Subsurface Rotation Rate Residuals and Radial Magnetic Field in Different Timescales
Howe, Rachel; Inceoglu, Fadil; Loto'aniu, Paul T. M.
We studied the presence and spatiotemporal characteristics and evolution of the variations in the differential rotation rates and radial magnetic fields in the Schwabe and quasi-biennial-oscillation (QBO) timescales. To achieve these objectives, we used rotation rate residuals and radial magnetic field data from the Michelson Doppler Imager on the…