David M. Long
A5015248371- Solar and Space Plasma Dynamics
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Ionosphere and magnetosphere dynamics
- Geomagnetism and Paleomagnetism Studies
- Solar Radiation and Photovoltaics
- Radiation Effects in Electronics
- Advancements in Semiconductor Devices and Circuit Design
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Semiconductor materials and devices
- Magnetic confinement fusion research
- Photocathodes and Microchannel Plates
- CCD and CMOS Imaging Sensors
- Atmospheric Ozone and Climate
- Integrated Circuits and Semiconductor Failure Analysis
- Particle accelerators and beam dynamics
- Calibration and Measurement Techniques
- Atomic and Subatomic Physics Research
- Nuclear Physics and Applications
- Earthquake Detection and Analysis
- Fusion materials and technologies
- Silicon and Solar Cell Technologies
- Planetary Science and Exploration
- Physics of Superconductivity and Magnetism
Dublin City University
2024-2025
Dublin Institute For Advanced Studies
2025
Queen's University Belfast
2023-2024
China Pharmaceutical University
2024
University College London
2014-2023
Flathead Valley Community College
2022
California Polytechnic State University
2022
Japan Aerospace Exploration Agency
2020
National Institute for Fusion Science
2020
UCL Australia
2014
Context. The Extreme Ultraviolet Imager (EUI) is part of the remote sensing instrument package ESA/NASA Solar Orbiter mission that will explore inner heliosphere and observe Sun from vantage points close to out ecliptic. advance “connection science” between solar activity heliosphere. Aims. With EUI we aim improve our understanding structure dynamics atmosphere, globally as well at high resolution, latitude perspectives. Methods. consists three telescopes, Full two High Resolution Imagers,...
The goal of this paper is to study the smallest brightening events observed in EUV quiet Sun. We use commissioning data taken by EUI instrument onboard recently launched Solar Orbiter mission. On 2020 May 30, was situated at 0.556AU from Its HRIEUV telescope 17.4nm passband reached an exceptionally high two-pixel spatial resolution 400km. size and duration small-scale structures determined data, while their height estimated triangulation with simultaneous SDO/AIA data. This first stereoscopy...
Abstract The severe geomagnetic effects of solar storms or coronal mass ejections (CMEs) are to a large degree determined by their propagation direction with respect Earth. There is lack understanding the processes that determine non-radial propagation. Here we present synthesis data from seven different space missions fast CME, which originated in an active region near disk centre and, hence, significant impact was forecasted. However, CME demonstrated be channelled during eruption into...
Taking advantage of both the high temporal and spatial resolutions Atmospheric Imaging Assembly on board Solar Dynamics Observatory, we studied a limb coronal shock wave its associated extreme ultraviolet (EUV) that occurred 2010 June 13. Our main findings are: (1) appeared clearly only in channels centered at 193 Å 211 as dome-like enhancement propagating ahead semi-spherical mass ejection (CME) bubble; (2) density compression is 1.56 according to radio data temperature around 2.8 MK; (3)...
Experiments have been conducted to determine the burnout susceptibility of power MOSFET devices exposed heavy ions from a Californium-252 source. This report documents results first single event tests performed on n-channel enhancement mode MOSFETs. Presented are, test method, results, description an observed latched current and discussion possible failure mechanism. The include dependence upon applied drain source bias variation in for various manufacturers
The kinematics of a globally propagating disturbance (also known as an ``EIT wave") is discussed using Extreme UltraViolet Imager (EUVI) data Solar Terrestrial Relations Observatory (STEREO). We show for the first time that impulsively generated has similar in all four EUVI passbands (304, 171, 195, and 284 A). In 304 A passband shows velocity peak 238+/-20 kms-1 within ~28 minutes its launch, varying acceleration from 76 ms-2 to -102 ms-2. This contains strong contribution Si XI line...
The X8.2 event of 10 September 2017 provides unique observations to study the genesis, magnetic morphology and impulsive dynamics a very fast CME. Combining GOES-16/SUVI SDO/AIA EUV imagery, we identify hot ($T\approx 10-15$ MK) bright rim around quickly expanding cavity, embedded inside much larger CME shell 1-2$ MK). develops from dense set large AR loops ($\gtrsim$0.5 $R_s$), seamlessly evolves into front observed in LASCO C2. strong lateral overexpansion acts as piston initiating wave....
Switchbacks are sudden, large radial deflections of the solar wind magnetic field, widely revealed in interplanetary space by Parker Solar Probe. The switchbacks' formation mechanism and sources still unresolved, although candidate mechanisms include Alfv\'enic turbulence, shear-driven Kelvin-Helmholtz instabilities, interchange reconnection, geometrical effects related to spiral. This Letter presents observations from Metis coronagraph onboard Orbiter a single propagating S-shaped vortex,...
Abstract Magnetic reconnection is a key mechanism involved in solar eruptions and also prime possibility to heat the low corona millions of degrees. Here, we present ultra-high-resolution extreme ultraviolet observations persistent null-point at scale about 390 km over one hour Extreme-Ultraviolet Imager on board Solar Orbiter spacecraft. The show formation configuration above minor positive polarity embedded within region dominant negative near sunspot. gentle phase evidenced by sustained...
Coronal holes are areas on the Sun with open magnetic field lines. They a source region of solar wind, but how wind emerges from coronal is not known. We observed hole using Extreme Ultraviolet Imager Solar Orbiter spacecraft. identified jets scales few hundred kilometers, which last 20 to 100 seconds and reach speeds ~100 kilometers per second. The powered by reconnection have kinetic energy in picoflare range. intermittent widespread within hole. suggest that such could produce enough...
Abstract Coronal loop oscillations are common phenomena in the solar corona, which often classified as decaying and decayless oscillations. Using high-resolution observation measured by Extreme Ultraviolet Imager (EUI) on board Solar Orbiter, we statistically investigate small-scale transverse with short periods (<200 s) of coronal loops an active region (AR), i.e., NOAA AR 12965. A total 111 identified EUI 174 Å images, they all reveal without any significant decaying, regarded...
The ambient solar wind that fills the heliosphere originates from multiple sources in corona and is highly structured. It often described as high-speed, relatively homogeneous, plasma streams coronal holes slow-speed, variable, whose source regions are under debate. A key goal of ESA/NASA's Solar Orbiter mission to identify understand what drives complexity seen heliosphere. By combining magnetic field modelling spectroscopic techniques with high-resolution observations measurements, we show...
Abstract ESA/NASA’s Solar Orbiter (SO) enables us to study the solar corona at closer distances and from different perspectives, which helps gain significant insights into origin of wind. In this work, we present analysis wind outflows two locations: a narrow open-field corridor small, mid-latitude coronal hole. These were observed off-limb by Metis coronagraph onboard SO on-disk Extreme Ultraviolet Imaging Spectrometer (EIS) Hinode. Magnetic field extrapolations suggest that upflow regions...
For almost 20 years the physical nature of globally propagating waves in solar corona (commonly called "EIT waves") has been controversial and subject to debate. Additional theories have proposed over explain observations that did not agree with originally fast-mode wave interpretation. However, incompatibility made using Extreme-ultraviolet Imaging Telescope (EIT) onboard Solar Heliospheric Observatory interpretation was challenged by differing viewpoints from twin Terrestrial Relations...
Context. The Extreme Ultraviolet Imager (EUI), onboard Solar Orbiter consists of three telescopes: the two High Resolution Imagers in EUV (HRIEUV) and Lyman-{\alpha} (HRILya), Full Sun (FSI). Orbiter/EUI started its Nominal Mission Phase on 2021 November 27. Aims. EUI images from largest scales extended corona off limb, down to smallest features at base chromosphere. is therefore a key instrument for connection science that heart mission goals. Methods. highest resolution achieved when...
After many years of fusion research, the conditions needed for a D–T reactor have been approached on Tokamak Fusion Test Reactor (TFTR) [Fusion Technol. 21, 1324 (1992)]. For first time unique phenomena present in plasma are now being studied laboratory plasma. The magnetic experiments to study plasmas using nearly equal concentrations deuterium and tritium carried out TFTR. At maximum power 10.7 MW, 39.5 MW neutral-beam heating, supershot discharge 6.7 high-βp following current rampdown....
A Thomson scattering apparatus for measuring the electron temperature and density along a 90-cm diam of PLT plasma has been built. wide angle objective images 3-mm x 900-mm ruby laser beam onto an image dissector which rearranges 300:1 to 20:1 forming input slit spectrometer. The stigmatic spectrometer provides twenty wavelength elements ~70 each. microchannel-plate intensifier optically coupled cooled SIT tube detection with single frame linearity 1000:1 dynamic range. Spatial profiles N(e)...
Coronal mass ejections (CMEs) erupt and expand in a magnetically structured solar corona. Various indirect observational pieces of evidence have shown that the magnetic field CMEs reconnects with surrounding fields, forming, e.g., dimming regions distant from CME source regions. Analyzing Solar Dynamics Observatory (SDO) observations eruption AR 11226 on 2011 June 7, we present first direct coronal reconnection between fields two adjacent ARs during CME. The are presented jointly...
We study here the phenomena of decayless kink oscillations in a system active region (AR) coronal loops. Using high resolution observations from two different instruments, namely Extreme Ultraviolet Imager (EUI) on board Solar Orbiter and Atmospheric Imaging Assembly (AIA) Dynamics Observatory, we follow these AR loops for an hour each three consecutive days. Our results show significantly more resolved waves higher-resolution EUI data compared with AIA data. Furthermore, same exhibits many...
Relaxation of braided coronal magnetic fields through reconnection is thought to be a source energy heat plasma in active region loops. However, observations heating associated with an untangling braids remain sparse. One reason for this paucity could the lack sufficiently high spatial and temporal resolution capture process action. Using new (250-270 km on Sun) cadence (3-10 s) from Extreme Ultraviolet Imager (EUI) board Solar Orbiter, we observed small-scale different regions. The...
Abstract From 2022 March 18 to 21, NOAA Active Region (AR) 12967 was tracked simultaneously by Solar Orbiter at 0.35 au and Hinode/EIS Earth. During this period, strong blueshifted plasma upflows were observed along a thin, dark corridor of open magnetic field originating the AR’s leading polarity continuing toward southern extension northern polar coronal hole. A potential source surface model shows large lateral expansion corridor. Squashing factor Q -maps large-scale topology further...
Abstract As both Parker Solar Probe (PSP) and Orbiter (SolO) reach heliocentric distances closer to the Sun, they present an exciting opportunity study structure of coronal mass ejections (CMEs) in inner heliosphere. We analysis global flux rope 2022 September 5 CME event that impacted PSP at a distance only 0.07 au SolO 0.69 au. compare situ measurements determine local expansion measures, finding good agreement between magnetic field relationships with distance, but significant differences...
Context. To meet the scientific objectives of mission, Solar Orbiter spacecraft carries a suite in-situ (IS) and remote sensing (RS) instruments designed for joint operations with inter-instrument communication capabilities. Indeed, previous missions have shown that Sun (imaged by RS instruments) heliosphere (mainly sampled IS should be considered as an integrated system rather than separate entities. Many advances expected from rely on this synergistic approach between measurements. Aims....