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The Airborne Lighting Observatory for FEGS and TGFs (ALOFT) is a field campaign focused on observing Terrestrial Gamma-ray Flashes (TGFs) and gamma-ray glows from thunderclouds. ALOFT will be flown on a NASA ER-2 research aircraft, flying at 20 km altitude, and the payload includes:1) Fly’s Eye GLM Simulator (FEGS), an array of imaging photometers as well as different wavelengths, and electric field change meters.2) Lightning Instrument Package (LIP), giving three component electric field measurements.3) Several gamma-ray detectors covering four orders of magnitude dynamic range in flux as well as the full energy range for TGF/gamma-ray glow detection.ALOFT is scheduled for July 2023, with 50 flight hours based out of Florida. Flying over thunderstorms in Central America and Caribbean, one of the most active TGF regions on the planet during the most optimal season, the ALOFT campaign will help us to answer the questions:1) How and under what conditions are TGFs produced?2) How extended in space and time are the gamma-ray glows?To answer question 1), the ALOFT campaign will be supported by ground based radio measurements from different locations in Central America and Caribbean.To answer question 2), with realtime downlink of data we will know when the ER-2 encounters gamma-ray glowing thunderclouds, and we will instruct the pilot to have the aircraft perform have repeated overflights over this cloud as long as the glow exists, to answer question 2). This will also help us understand whether gamma-ray glows and TGFs are interrelated.The full set of observational goals of ALOFT are:1. Observe TGFs in one of the most TGF-intense regions on the planet.2. Observe gamma-ray glows in thunderstorms and their relation to TGFs.3. Perform International Space Station Lightning Imaging Sensor (ISS LIS) and Global Lightning Monitor (GLM) validation using improved suborbital instrumentation (including upgraded FEGS).4. Evaluate new design concepts for next-generation spaceborne lightning mappers.5. If relevant instrumentation is available, make measurements useful to advance convection science from a suborbital platform.In this presentation we will give the status and plans for the ALOFT mission.

ALOFT (Airborne Lightning Observatory for FEGS and TGFs) is a flight campaign designed to observe Terrestrial Gamma-ray Flashes (TGF) and gamma-ray glows close to their production source. The campaign consists of 50 flight hours of a NASA ER-2 research aircraft taking off from Florida and is scheduled for July 2023. The ER-2 cruise altitude of 20 km allows flying over active thunderstorms in the Gulf of Mexico and Caribbean region, one of the most TGF-active region on the planet. The main challenge for TGF detection at close distance is the large variability in the expected gamma-ray flux, spanning four orders of magnitude depending on the radial distance from the source. To cope with this challenge, the ALOFT gamma-ray payload consists of several detectors of different size, made of different materials and readout sensors, designed to cover 4 orders of magnitude dynamic range on the typical TGF/gamma-ray glow energy range (~100 keV - ~40 MeV). In addition, the payload includes the Fly’s Eye GLM Simulator (FEGS), an array of imaging photometers sensitive at different wavelengths, and electric field change meters, and the Lightning Instrument Package (LIP), giving three component electric field measurements. The synergy between airborne gamma-ray, optical and electric field measurements, combined with ground-based radio observations, will provide a unique set of observations to constrain the source properties and their physics. This presentation will focus on the ALOFT scientific payload and the system architecture.

The role of seapower in World War II was central to explaining Allied victory. Control of a global network of maritime communication meant being able to fight in distant theatres, being able to supply material assistance between allies, and being able to choose the place and timing of amphibious operations. The Axis, it is argued, had few advantages once Allied naval power was fully mobilized. Even the U-Boat war in the Atlantic was less impressive than usually argued. Strangling Japanese overseas supply was a major factor in Japan’s defeat.

There is a growing interest in the science uniquely enabled by observations in the MeV range, particularly in light of multi-messenger astrophysics. The Compton Pair (ComPair) telescope, a prototype of the AMEGO Probe-class concept, consists of four subsystems that together detect and characterize gamma rays in the MeV regime. A double-sided strip silicon Tracker gives a precise measure of the first Compton scatter interaction and tracks pair-conversion products. A novel cadmium zinc telluride (CZT) detector with excellent position and energy resolution beneath the Tracker detects the Compton-scattered photons. A thick cesium iodide (CsI) calorimeter contains the high-energy Compton and pair events. The instrument is surrounded by a plastic anti-coincidence (ACD) detector to veto the cosmic-ray background. In this work, we will give an overview of the science motivation and a description of the prototype development and performance.

The LargE Area burst Polarimeter (LEAP) is one of two NASA Missions of Opportunity proposals that are currently in a Phase A Concept Study, with a final selection due later this year. It is a wide Field of View (FoV) Compton polarimeter designed to study Gamma-Ray Burst (GRB) polarization over the energy range from 50- 500 keV and to measure GRB spectra in the range from 20 keV - 5 MeV. During the Phase A Concept Study, lab measurements were conducted with a small-scale (5x5) prototype polarimeter module. This included both spectral and polarization measurements with laboratory calibration sources. Here the prototype measurements and the comparisons made with simulations of the prototype detector are described. These results demonstrate the basic functionality of the LEAP design.

The LargE Area Burst Polarimeter (LEAP) will radically improve our understanding of some of the most energetic phenomena in our Universe by exposing the underlying physics that governs astrophysical jets and the extreme environment surrounding newborn compact objects. LEAP will do this by making the highest fidelity polarization measurements to date of the prompt gamma-ray emission from a large sample of Gamma-Ray Bursts (GRBs). The science objectives are met with a single instrument deployed as an external payload on the ISS – a wide FOV Compton polarimeter that measures GRB polarization from 50–500 keV and GRB spectra from ~10 keV to 5 MeV. LEAP measures polarization using seven independent polarimeter modules, each with a 12x12 array of optically isolated high-Z and low-Z scintillation detectors readout by individual PMTs. LEAP is one of two NASA Missions of Opportunity proposals that are currently in a Phase A Concept Study, with a final selection due later this year.

USS Nevada was one of the first of a new generation of American dreadnoughts. She and her half-sister Oklahoma pioneered ‘all or nothing’ protection and oil burning as designed. She had turbines, b...

The ‘Battle of the Atlantic’ is a powerful legend. Throughout the war, it is said, a ‘battle’ raged as the Germans mounted a near decisive attack on the shipping that lay at the heart of the Allied...

This is Andrew Lambert’s most ambitious book. In it he sets out an interesting and original thesis that ‘seapower states’ have been the result of the ambitions of an oligarchic elite, based on mari...

Monte Carlo simulations are used to determine source properties of terrestrial gamma-ray flashes (TGFs) as a function of atmospheric column depth and beaming geometry. The total mass per unit area traversed by all the runaway electrons (i.e., the total grammage) during a TGF, Ξ, is introduced, defined to be the total distance traveled by all the runaway electrons along the electric field lines multiplied by the local air mass density along their paths. It is shown that key properties of TGFs may be directly calculated from Ξ and its time derivative, including the gamma-ray emission rate, the current moment, and the optical power of the TGF. For the calculations presented in this paper, a standard TGF gamma-ray fluence, F0 = 0.1 cm-2 above 100 keV for a spacecraft altitude of 500 km, and a standard total grammage, Ξ0 = 1018 g/cm2, are introduced, and results are presented in terms of these values. In particular, the current moments caused by the runaway electrons and their accompanying ionization are found for a standard TGF fluence, as a function of source altitude and beaming geometry, allowing a direct comparison between the gamma rays measured in low-Earth orbit and the VLF-LF radio frequency emissions recorded on the ground. Such comparisons should help test and constrain TGF models and help identify the roles of lightning leaders and streamers in the production of TGFs.

The battle of Jutland was a paradox, a massive naval engagement with little result. Thousands of men were lost in an indecisive clash that settled nothing. This account sets out its author’s interpretation of the battle. Key reasons for the battle being indecisive were the contrasting characters of the British Grand Fleet’s commanders. Admiral Jellicoe, the commander-in-chief was intelligent, thoughtful and a thorough administrator who inspired great loyalty among his subordinates but was unwilling to take the risks required for forcing a decisive action. Vice-Admiral David Beatty was the opposite, instinctively aggressive but thoughtless and inexperienced as a fleet commander. The German commanders were stronger overall, attempting to make the most of the quantitatively inferior and less well-armed High Sea Fleet. Their aim was to even up capital ship strength by trapping and defeating smaller portions of the Grand Fleet. Following the battle the Germans, despite having fled for home, claimed victory as ...

Background neutron measurements were recorded for approximately two months at Camp Blanding, FL, with a large array of moderated gas proportional detectors and EJ-309 liquid scintillator detectors. The variations in the local neutron background rate were on the order of 10% and were observed to be primarily due to the changing level of moisture in the local soil due to precipitation and evaporation. Simple models were constructed based only on very basic climatological information and were able to reproduce the major variations in our measured neutron counts with time. These simple models compare favorably to the more-complex modified Penman equation developed for the California Irrigation Management Information System. An accurate model to describe local neutron background variations based on easily measured climatological data would be invaluable to provide corrections for stationary neutron monitors.

For over ten years Seaforth, the thriving maritime dimension of Pen and Sword of Barnsley, have published an annual review of naval developments. This is the latest edition published at the end of ...

Dr Toshio Yushihara has had posts at the Naval War College at Newport Rhode Island and at the Fletcher School of Law and Diplomacy. He is now a senior fellow at the Center for Strategic and Budgeta...

We present our results on the second year of TOTO-Cheyenne (TGFs On Top Of Cheyenne), a continuing collaboration of the US Air Force Academy and the Naval Research Laboratory. The project's goal is...

I have to admit to have been putting off reading and reviewing this book; I am grateful to the reviews editor for his forbearance. The reason is that I know, like and admire Professor Jeremy Black ...

The Strontium Iodide Radiation Instrument (SIRI) is a single detector, gamma-ray spectrometer designed to space-qualify the new scintillation detector material europium-doped strontium iodide (SrI2:Eu) and new silicon photomultiplier (SiPM) technology. SIRI covers the energy range from 0.04-8 MeV and was launched into 600 km sun-synchronous orbit on Dec 3, 2018 onboard STPSat5 with a one-year mission to investigate the detector's response to on-orbit background radiation. The detector has an active volume of 11.6 cm3 and a photo fraction efficiency of 50% at 662 keV for gamma-rays parallel to the long axis of the crystal. Its spectroscopic resolution of 4.3% was measured by the FWHM of the characteristic Cs-137 gamma-ray line at 662 keV. Measured background rates external to the trapped particle regions are 40-50 counts per second for energies greater than 40 keV and are largely the result of short- and long-term activation products generated by transits of the SAA and the continual cosmic-ray bombardment. Rate maps determined from energy cuts of the collected spectral data show the expected contributions from the various trapped particle regions. Early spectra acquired by the instrument show the presence of at least 10 characteristic gamma-ray lines and a beta continuum generated by activation products within the detector and surrounding materials. As of April 2019, the instrument has acquired over 1000 hours of data and is expected to continue operations until the space vehicle is decommissioned in Dec. 2019. Results indicate SrI2:Eu provides a feasible alternative to traditional sodium iodide and cesium iodide scintillators, especially for missions where a factor-of-two improvement in energy resolution would represent a significant difference in scientific return. To the best of our knowledge, SIRI is the first on-orbit use of SrI2:Eu scintillator with SiPM readouts., Comment: 9 pages, 14 figures, conference IEEE NSSMIC Manchester, 2019

This paper will focus on next-generation inorganic scintillation detectors that could be used to study neutral emission from the high-energy Sun. Recent developments in detector technology have yielded candidate materials for future heliophysics missions, namely elpasolites (Cs2LiYCl6:Ce – CLYC and Cs2LiLaBr6:Ce – CLLB). At a modest cost, these detectors yield superior spectroscopic performance compared to previously used materials (NaI:Tl and CsI:Tl). Additionally, elpasolites can detect and measure thermal to fast (

Background Exposure to cold is associated with increased energy expenditure to maintain thermal equilibrium. The Cool Fat Burner vest and Gut Buster are chilling devices used to induce shivering and increase calorie use. Drinking chilled water has a similar effect. Methods Indirect calorimetry was performed on volunteers at rest with induced shivering. Eight men and 6 women with a mean age of 32.14+7.26 years were evaluated while wearing the Cool Fat Burner Vest and Gut Buster and drinking chilled water. Results Use of the chilling devices was associated with a significant increase in VO2, VT, VE, R, and EE. An over 20% increase in fat use as a fuel source was observed along with a 67% increase in EE. The energy expenditure during the final 30 minutes of shiver chilling was 74.6% above that of the RMR. Chilling induced significant increases in energy expenditure associated with a shift in energy source towards more fat tissue use. Conclusions Indirect calorimetry evaluation of overweight subjects wearing a Cool Fat Burner vest and Gut Buster and drinking chilled water demonstrated significant increases in oxygen uptake and energy expenditure, and a shift in fuel utilization towards fat as the substrate of choice.

We report on the development of the thallium-doped cesium iodide (CsI:Tl) calorimeter subsystem for the All-Sky Medium-Energy Gamma-ray Observatory (AMEGO) [1]. The CsI:Tl calorimeter is one of the three main subsystems that comprise the AMEGO instrument suite; the others include the double-sided silicon strip detector (DSSD) tracker/converter and a cadmium zinc telluride (CZT) calorimeter. Similar to the LAT instrument on Fermi Gamma-ray Space Telescope, the hodoscopic calorimeter consists of orthogonally layered CsI:Tl bars. Unlike the LAT, which uses PIN photodiodes, the scintillation light from each end of the CsI:Tl bar is read out with recently developed large-area silicon photomultiplier (SiPM) arrays. Development of the calorimeter technology for a large space-based {\gamma}-ray observatory is being done via funding from the NASA APRA program. Under this program, we have designed, built and are currently testing a prototype consisting of 24 CsI:Tl bars (each with dimensions of 16.7 mm x 16.7 mm x 100 mm) hodoscopically arranged in four layers with six bars per layer. The ends of each bar are read out with SensL ArrayJ quad SiPMs. Signal readout and processing is done with the IDEAS SIPHRA (IDE3380) ASIC. Performance testing of this prototype was done with laboratory sources and at an initial beam test; future testing and characterization will be done during a second beam test (2019) and a balloon flight (2020) in conjunction with the other subsystems led by NASA-GSFC. We will discuss the initial calibration tests, construction of the prototypes and the most up-to-date results from laboratory and beam tests with analog/digital electronics and the SIPHRA DAQ., Comment: 6 pages, 10 figures, IEEE NSS MIC proceedings paper, submitted 12/15/18

The essence of NATO was that it was an Atlantic alliance, binding U.S. power to the defence of Western Europe against a Soviet attack, and therefore guarding the free use of the Atlantic. It was intended to make a quick Soviet victory impossible and protect the maritime flanks of Europe. Its credibility in this role contributed essentially to the eventual collapse of the Soviet system. RESUME. Le principe de l'OTAN etait de constituer une alliance atlantique, engageant la puissance americaine a defendre l'Europe occidentale contre une attaque sovietique, et par la meme de preserver la libre exploitation de l'Atlantique. Elle avait pour but de rendre impossible une victoire sovietique rapide et de proteger les bords maritimes europeens. Sa credibilite en la matiere contribua grandement a l'effondrement du systeme sovietique. The North Atlantic Treaty, signed in Washington on 4 April 1949, was always a fundamentally maritime arrangement. Although at first it seemed that the major strategic priority was tying US long-range strategic nuclear air power to a more credible defence of Western Europe, the title of the organisation it set up, the North Atlantic Treaty Organisation(NATO), demonstrated that the foundation of the alliance was the ability of the USA – and Canada – to project their military power across a major maritime space, the Atlantic Ocean. The Alliance also contained the other main Western European naval powers, Britain, France and the Netherlands. The Medium Term Defence Plan adopted by the Alliance's Military Committee in 1949 stressed successful defence against any Soviet attack and then moving forward to offensive operations that would eventually achieve war termination on the Alliance's terms. This campaign would be supported by control of North Atlantic sea and air lines of communication. In October the North Atlantic Regional Planning Group with representatives from the USA, Britain, France, Canada, Denmark, the Netherlands, Norway, Belgium, Portugal and Iceland was tasked with drafting plans for a unified defence of the North Atlantic area. There were five planning sub-groups, the first on offensive operations. This sub-group was formed only of US and British representatives although there was a permanent French observer. Its task was: “To prepare broad plans for offensive action against enemy armed forces and shipping, their bases and port facilities, including attack at source, amphibious and airborne operations and offensive mining.”

“Sea power” refers to the power exerted by a state through its capacity to use the sea for both military and civilian purposes. The ability to use the seas for transport and other civilian purposes such as fishing and, more recently, exploitation of resources on or under the sea bed has generated considerable debate. This has resulted in the notion that military power deployed at or from the sea is the key component of a state’s sea power. It was Alfred Thayer Mahan who first coined the term “sea power.” In his 1980 book “Influence,” Mahan outlined six “principal conditions affecting the sea power of nations”: geographical position, physical conformation, extent of territory, number of population, national character, and character of government. After Mahan, other writers advanced a variety of ideas regarding the concept of sea power, including Philip Colomb, who emphasized the importance of “command of the sea”; Sir Julian Corbett, who discussed the importance of maritime “lines of passage and communication” as “the preoccupation of naval strategy,” and control of such lines as the essence of “command of the sea”; and Sir Herbert Richmond, whose definition of sea power can be summed up as the “power to control movements at sea.” Others who have contributed to the scholarly literature on sea power include Raoul Castex, Bernard Brodie, Stephen Roskill, Sir Peter Gretton, Sir James Cable, Sergei G. Gorshkov, Paul Kennedy, Ken Booth, Richard Hill, and Geoffrey Till.

Dr Sebastian Bruns is head of the Center for Maritime Strategy and Security at the Institute for Security Policy at the University of Kiel. Together with the American Center for Naval Analyses he f...