Dr
Patrick Blaes
(Stanford Univ.)
30/09/2013, 09:30
Lightning return strokes radiate an electromagnetic pulse (EMP) which interacts with the D-region ionosphere. The largest EMPs produce new ionization, heating, and optical emissions known as elves. Elves are among the most common transient luminous events, occurring at least six times more frequently than sprites. In this talk, a brief overview of elve research is presented. Additionally,...
Prof.
Ningyu Liu
(Florida Institute of Technology)
30/09/2013, 10:15
Sprites are electrical discharges in the mesosphere/lower ionosphere caused by strong cloud-to-ground lightning flashes. They are highly structured with dominant filamentary structures known as streamers. They also exhibit highly dynamical properties. In this talk, we will present an overview of recent observational and modeling studies of sprites in North America. We will discuss the...
Dr
Enrico Arnone
(ISAC-CNR)
30/09/2013, 11:30
Lightning and high energy processes are observed in the
atmosphere above thunderstorms. These phenomena impact the Earth's
atmosphere through ion-neutral chemistry reactions leading to additional
chemical sources which are as yet not included in the present picture of
atmospheric chemistry and climate. In this talk, we will revise results of
sprite-chemistry models and observations, and...
Dr
Patrick Blaes
(Stanford Univ.)
30/09/2013, 14:15
We present observations of elves using a ground-based, free-running photometer array called Photometric Imager of Precipitated Electron Radiation (PIPER). The PIPER photometer has a high (40µs) temporal resolution, making it ideal for studying fast TLEs such as elves. As a free-running instrument, it can record entire storms and there are no missed detections or sampling bias due to...
Dr
Fernanda de Sao Sabbas Tavares
(INPE-National Institute for Space Research)
30/09/2013, 15:00
South America’s combination of intense thunderstorm activity and geomagnetic characteristics creates a unique natural laboratory for investigating a variety of atmospheric phenomena and their possible coupling. Its large latitudinal extent, from ~12o N to ~55o S, encompass equatorial, tropical and subtropical regions with meteorological conditions that makes South America the second most...
Dr
Roberto Mussa
(INFN Torino)
30/09/2013, 16:15
The Pierre Auger Observatory near Malargue (Argentina), is the largest facility (3000 km2) for the study of
Ultra High Energy Cosmic Rays (E>10^18 eV). The four sites of the Fluorescence Detector (FD), covering a field of view of 30x180 degrees) observe the night sky with 100 ns time resolution and a space resolution of about 1 degree. After the first serendipitous observation of an ELVES...
Dr
Mario Bertaina
(INFN & University Torino)
30/09/2013, 17:00
The Extreme Universe Space Observatory on board of the Japanese Experiment
Module (JEM-EUSO) is a new type of observatory to be placed on the
International Space Station after 2017 to observe Ultra High Energy Cosmic
Rays (E>5x10^19 eV) from space. Among the exploratory objectives of the
mission there is also the observation of the Transient Luminous Events
(TLEs).
In this presentation...
Prof.
Lawrence Wiencke
(Colorado School of Mines)
30/09/2013, 17:45
The serendipitous observation of atmospheric Elves by the Pierre Auger Observatory has demonstrated that cosmic ray air fluorescence detectors can measure transient luminous events quite well. TLE measurements are also an important component of the science program that is planned for JEM-EUSO. In this talk I will discuss the possibility of using a simplified optical cosmic ray detector,...
Dr
Levon Vanyan
(Yerevan Physics Institute)
01/10/2013, 09:00
During thunderstorm activities ground based particle detectors register enhancements in fluxes of secondary cosmic ray fluxes - Thunderstorm Ground Enhancements(TGE’s). These events are particularly explained by Runaway Breakdown model of initiation of lightnings. The model gives a threshold, minimal value of atmospheric electric fields strengths, in case of which multiplication of secondary...
Dr
Julian Rautenberg
(Bergische Univ. Wuppertal)
01/10/2013, 09:45
The process that initiates lightning inside thunderclouds is not yet understood. Extended air shower from cosmic rays provide electrons and particles that in energetic runaway processes could trigger lightning. The Pierre Auger Observatory is the largest experiment measuring cosmic rays. The sensitivity to lightnings of the different detector types of the hybrid observatory as well as...
Dr
Silvia Vernetto
(INAF Torino)
01/10/2013, 10:30
ARGO-YBJ is an air shower detector that operated from 2007 to 2013 at the
Cosmic Ray Laboratory of Yangbajing (Tibet, China) at 4300 m a.s.l.
devoted to Gamma Ray Astronomy and Cosmic Ray studies in the TeV energy range.
During thunderstorms ARGO-YBJ observed significant variations of the flux
of secondary particles of cosmic rays, strongly correlated with the local atmospheric electric...
Dr
Levon Vanyan
(Yerevan Physics Institute)
01/10/2013, 11:20
We analyze the neutron fluxes correlated with thunderstorm activity recently measured at mountain altitudes by Aragats and other groups. We perform simulations of the photonuclear reactions of gamma rays born in the electron-gamma ray avalanches and calculate the expected count rates of the neutron detectors. Our analysis supports the Tibet and Aragats group's conclusions on the photonuclear...
Dr
Vincenzo Vitale
(Univ. Roma Tor Vergata)
01/10/2013, 12:00
During thunderstorm activities ground based particle detectors register enhancements in fluxes of secondary cosmic ray fluxes - Thunderstorm Ground Enhancements(TGE’s). These events are particularly explained by Runaway Breakdown model of initiation of lightnings. The model gives a threshold, minimal value of atmospheric electric fields strengths, in case of which multiplication of secondary...
Dr
Martino Marisaldi
(INAF - IASF Bologna)
01/10/2013, 14:05
The AGILE satellite detects more than 10 Terrestrial Gamma-ray Flashes (TGFs) per month in the latitude belt +/- 2.5 deg, providing the largest TGF surface density observed and the largest TGF statistics in the equatorial region to date. The current TGF sample comprises more than 400 events with maximum energy lower than 30 MeV detected by the Minicalorimeter (MCAL) instrument on-board...
Dr
Luca Latronico
(INFN Torino)
01/10/2013, 14:50
The Fermi LAT regularly detects Terrestrial Gamma-ray Flashes (TGFs)
during its nominal astrophysical sky-survey observing program. Because of
the LAT's flexible trigger logic, TGF emissions at and above 10 MeV are
detected with high sensitivity despite their having arrived from outside
the instrument's field of view. A deep search of the first four years of
LAT data reveals more than 300...
Dr
Paul Connell
(Univ. Valencia - Image Processing Laboratory)
01/10/2013, 16:05
We present here the instruments of the ASIM mission to the ISS in 2015 to observe TGFs and associated TLEs, its current status of construction and testing. We will also talk about a new software package being developed at the University of Valencia to simulate the scattering physics of MeV electrons so that users interested in simulating theories of TGF origin will only have to specify the...
Dr
Suzanne Foley
(Univ.College Dublin)
01/10/2013, 16:50
We present refined analyses of TGFs detected by the Gamma-ray Burst Monitor (GBM) instrument onboard Fermi. Of a sample of ~300 bright TGFs that triggered GBM, 19% are found to have multiple pulses. The individual pulses can be either be symmetric or asymmetric and are well fit with Gaussian or log-normal functions. A new data mode has been used to detect TGFs with GBM 10 times more frequently...