Publications (25)
A Giant Peanut-shaped Ultra-High-Energy Gamma-Ray Emitter Off the Galactic Plane
Zhen Cao, Felix Aharonian, Yunxiang Bai +312
Ultra-high-energy (UHE), exceeding 100 TeV (10^12 electronvolts), γ-rays manifests extreme particle acceleration in astrophysical sources. Recent observations by γ-ray telescopes…
Variation in Path Lengths of Turbulent Magnetic Field Lines and Solar Energetic Particles
Wirin Sonsrettee, Piyanate Chuychai, Achara Seripienlert +5
Modeling of time profiles of solar energetic particle (SEP) observations often considers transport along a large-scale magnetic field with a fixed path length from the source to th…
Ultrahigh-Energy Gamma-ray Emission Associated with Black Hole-Jet Systems
The LHAASO Collaboration, Zhen Cao, Felix Aharonian +315
Black holes (BH), one of the most intriguing objects in the universe, can manifest themselves through electromagnetic radiation initiated by the accretion flow. Some stellar-mass B…
Magnetic Field Line Separation by Random Ballistic Decorrelation in Transverse Magnetic Turbulence
Chutima Yannawa, Peera Pongkitiwanichakul, David Ruffolo +2
The statistics of the magnetic field line separation provide insight into how a bundle of field lines spreads out and the dispersion of non-thermal particles in a turbulent environ…
The Alfvén Transition Zone observed by the Parker Solar Probe in Young Solar Wind -- Global Properties and Model Comparisons
Rohit Chhiber, Francesco Pecora, Arcadi V Usmanov +6
The transition from subAlfvénic to superAlfvénic flow in the solar atmosphere is examined by means of Parker Solar Probe (PSP) measurements during solar encounters 8 to 14. Aroun…
Role of Parallel Solenoidal Electric Field on Energy Conversion in 2.5D Decaying Turbulence with a Guide Magnetic Field
Peera Pongkitiwanichakul, David Ruffolo, Fan Guo +5
We perform 2.5D particle-in-cell simulations of decaying turbulence in the presence of a guide (out-of-plane) background magnetic field. The fluctuating magnetic field initially co…
Flow Crossover and Parallel Outflow during Collisionless Magnetic Reconnection
Theerasarn Pianpanit, Kittipat Malakit, Pakkapawn Prapan +5
Using particle-in-cell simulations that label ions and electrons according to their initial inflow region, we find that during 2D collisionless magnetic reconnection, the bulk flow…
Properties of Magnetic Switchbacks in the Near-Sun Solar Wind
Samuel T. Badman, Naïs Fargette, Lorenzo Matteini +24
Magnetic switchbacks are fluctuations in the solar wind in which the interplanetary magnetic field sharply deflects away from its background direction so as to create folds in magn…
Scale and Time Dependence of Alfvénicity in the Solar Wind as Observed by {\it Parker Solar Probe}
Panisara Thepthong, Peera Pongkitiwanichakul, David Ruffolo +4
Alfvénicity is a well-known property, common in the solar wind, characterized by a high correlation between magnetic and velocity fluctuations. Data from the Parker Solar Probe (P…
[Plasma 2020 Decadal] The essential role of multi-point measurements in turbulence investigations: the solar wind beyond single scale and beyond the Taylor Hypothesis
W. H. Matthaeus, R. Bandyopadhyay, M. R. Brown +46
This paper briefly reviews a number of fundamental measurements that need to be made in order to characterize turbulence in space plasmas such as the solar wind. It has long been k…
Variations in the Inferred Cosmic-Ray Spectral Index as Measured by Neutron Monitors in Antarctica
Pradiphat Muangha, David Ruffolo, Alejandro Sáiz +7
A technique has recently been developed for tracking short-term spectral variations in Galactic cosmic rays (GCRs) using data from a single neutron monitor (NM), by collecting hist…
Measuring contributions from single and multiple atmospheric secondary cosmic rays in the {\it Princess Sirindhorn Neutron Monitor} using cross-counter neutron time delay distributions
Warit Mitthumsiri, Alejandro Sáiz, David Ruffolo +4
Neutron monitors (NMs) are ground-based devices designed to measure cosmic-ray count rates by monitoring atmospheric neutrons from cosmic-ray showers. We present results from new e…
Characterization of the Trans-Alfvénic Region Using Observations from Parker Solar Probe
Subash Adhikari, Riddhi Bandyopadhyay, Joshua Goodwill +14
Close to Earth the solar wind is usually super-Alfvénic, i.e. the speed of the solar wind is much larger than the Alfvén speed. However, in the lower coronal regions, the solar w…
Random Walk and Trapping of Interplanetary Magnetic Field Lines: Global Simulation, Magnetic Connectivity, and Implications for Solar Energetic Particles
Rohit Chhiber, David Ruffolo, William H. Matthaeus +4
The random walk of magnetic field lines is an important ingredient in understanding how the connectivity of the magnetic field affects the spatial transport and diffusion of charge…
Cosmic Ray Diffusion Coefficients Throughout The Inner Heliosphere From Global Solar Wind Simulation
Rohit Chhiber, Prachanda Subedi, Arcadi V. Usmanov +4
We use a three-dimensional magnetohydrodynamic simulation of the solar wind to calculate cosmic ray diffusion coefficients throughout the inner heliosphere ( AU). Th…
Magnetic switchback formation: a review of proposed mechanisms
Peter F. Wyper, Jonathan Squire, Etienne Pariat +19
Magnetic switchbacks are large amplitude deflections of the magnetic field within the solar wind. They are Alfvénic in character and so are associated with a spike in velocity and…
A Large Ground-Based Observing Campaign of the Disintegrating Planet K2-22b
Knicole D. Colón, George Zhou, Avi Shporer +27
We present 45 ground-based photometric observations of the K2-22 system collected between December 2016 and May 2017, which we use to investigate the evolution of the transit of th…
Observed Fluctuation Enhancement and Departure from WKB Theory in Sub-Alfvénic Solar Wind
David Ruffolo, Panisara Thepthong, Peera Pongkitiwanichakul +12
Using Parker Solar Probe data from orbits 8 through 17, we examine fluctuation amplitudes throughout the critical region where the solar wind flow speed approaches and then exceeds…
Domains of Magnetic Pressure Balance in Parker Solar Probe Observations of the Solar Wind
David Ruffolo, Nawin Ngampoopun, Yash R. Bhora +4
The Parker Solar Probe (PSP) spacecraft is performing the first in situ exploration of the solar wind within 0.2 au of the Sun. Initial observations confirmed the Alfvénic nature…
On the Estimation of Solar Energetic Particle Injection Timing from Onset Times near Earth
Alejandro Saiz, Paul Evenson, David Ruffolo +1
We examine the accuracy of a common technique for estimating the start time of solar energetic particle injection based on a linear fit to the observed onset time versus 1/(particl…
Averaging Effects on the Solar Wind Alfven Mach Number: Implications for Switchbacks and Alfven Transition
Joshua Goodwill, Subash Adhikari, Francesco Pecora +10
Averaging techniques in solar wind measurements have been a longstanding subject of debate. Using Parker Solar Probe (PSP) observations from encounters 1 to 19, we investigate how…
The Large High Altitude Air Shower Observatory (LHAASO) Science Book (2021 Edition)
Zhen Cao, D. della Volpe, Siming Liu +87
Since the science white paper of the Large High Altitude Air Shower Observatory (LHAASO) published on arXiv in 2019 [e-Print: 1905.02773 (astro-ph.HE)], LHAASO has completed the tr…
The essential role of multi-point measurements in investigations of turbulence, three-dimensional structure, and dynamics: the solar wind beyond single scale and the Taylor Hypothesis
W. H. Matthaeus, S. Adhikari, R. Bandyopadhyay +49
Space plasmas are three-dimensional dynamic entities. Except under very special circumstances, their structure in space and their behavior in time are not related in any simple way…
Charged particle diffusion in isotropic random magnetic fields
Prachanda Subedi, Wirin Sonsrettee, Pasquale Blasi +8
The investigation of the diffusive transport of charged particles in a turbulent magnetic field remains a subject of considerable interest. Research has most frequently concentrate…
A New Electric Field in Asymmetric Magnetic Reconnection
Kittipat Malakit, Michael A. Shay, Paul A. Cassak +1
We present a theory and numerical evidence for the existence of a previously unexplored in-plane electric field in collisionless asymmetric magnetic reconnection. This electric fie…