Estimation of the global occurrence rate of elves with Mini-EUSO

Elves are the most common type of transient luminous events, with estimates of their global occurrence rate ranging from a few to a few tens per minute. Here, we present the first derivation of the global occurrence rate of elves from Mini-EUSO observations. Mini-EUSO is a wide field of view, space-based telescope operating from a nadir-facing UV-transparent window in the Russian Zvezda module on the International Space Station. It observes the Earth&#8217;s atmosphere in the UV band with a spatial resolution of about 6.3 km and a temporal resolution of 2.5 &#956;s. Its optical system made of two 25 cm diameter Fresnel lenses focuses the light into a square array of 48x48 pixels, each pixel being capable of single photon counting. Originally designed to detect the faint fluorescence light produced by extensive air showers induced by extreme energy cosmic rays, it was shown to be capable of detecting a wide range of atmospheric phenomena, including elves.&#160;Elves are dynamically traced by Mini-EUSO in their horizontally expanding, fast donut-shaped light emissions and can therefore be unequivocally identified. Mini-EUSO can usually detect elves whose center is just outside the field of view, following the expansion of the ring for hundreds of microseconds. Combining the number of detected elves with consideration of the time and geometries, it is possible to derive a first estimate of their global occurrence rate with Mini-EUSO, and to compare it to the literature.&#160;

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Observation of ELVES from the International Space Station with the Mini-EUSO telescope

10.5194/egusphere-egu21-11940 ◽

2021 ◽

Author(s):

Marco Casolino ◽

Mario Bertaina ◽

Enrico Arnone ◽

Laura Marcelli ◽

Lech Piotrowski ◽

...

Keyword(s):

International Space Station ◽

Single Photon ◽

Photon Counting ◽

Space Station ◽

Field Of View ◽

Single Photon Counting ◽

International Space ◽

Focal Surface ◽

The Earth ◽

Ultraviolet Emissions

Mini-EUSO is a telescope that observes the Earth from the International Space Station by recording ultraviolet emissions (290 &#247; 430 nm) of cosmic, atmospheric and terrestrial origin with a field of view of 44&#9702;, a spatial resolution of 6.3 km and a temporal resolution of 2.5 mus.The instrument is based on an optical system composed of two Fresnel lenses and a focal surface composed of 36 multi-anode photomultiplier tubes, 64 channels each, for a total of 2304 channels with single photon counting sensitivity.Mini-EUSO is a UV telescope launched in 2019&#160; &#160;and observing the Earth from the inside the Russian Zvezda module, through a nadir-facing UV-transparent.It is composed of a Fresnel optics (25 cm diameter, 44 deg field of view) and a Multi Anode Photomultiplier focal surface (2304 pixels, 6km on the surface) with a single-photon counting capability and a sampling rate of 400kHz.Its scientific objectives include the search for ultra-high energy cosmic rays (E>1e21eV), the study of&#160; meteors and search for interstellar objects and Strange Quark Matter, the&#160; mapping&#160; &#160;of the Earth's night-time ultraviolet emissions, the search for space debris.The characteristcs of the detector make it also well suited for the detection of TLEs, especially ELVES and the study of its development to extract spatial and temporal evolution.&#160; In this article we will focus our attention on the observation of single and multi-ringed elves.

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UVscope and its application aboard the ASTRI-Horn telescope

Experimental Astronomy ◽

10.1007/s10686-021-09728-6 ◽

2021 ◽

Author(s):

Maria Concetta Maccarone ◽

Giovanni La Rosa ◽

Osvaldo Catalano ◽

Salvo Giarrusso ◽

Alberto Segreto ◽

...

Keyword(s):

Gamma Ray ◽

Single Photon ◽

Photon Counting ◽

Light Flux ◽

Cosmic Ray ◽

High Energy ◽

Wide Field ◽

High Energy Astrophysics ◽

Single Photon Counting ◽

Photon Counting Mode

AbstractUVscope is an instrument, based on a multi-pixel photon detector, developed to support experimental activities for high-energy astrophysics and cosmic ray research. The instrument, working in single photon counting mode, is designed to directly measure light flux in the wavelengths range 300-650 nm. The instrument can be used in a wide field of applications where the knowledge of the nocturnal environmental luminosity is required. Currently, one UVscope instrument is allocated onto the external structure of the ASTRI-Horn Cherenkov telescope devoted to the gamma-ray astronomy at very high energies. Being co-aligned with the ASTRI-Horn camera axis, UVscope can measure the diffuse emission of the night sky background simultaneously with the ASTRI-Horn camera, without any interference with the main telescope data taking procedures. UVscope is properly calibrated and it is used as an independent reference instrument for test and diagnostic of the novel ASTRI-Horn telescope.

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Optical Estimation of Absolute Membrane Potential Using One- and Two-Photon Fluorescence Lifetime Imaging Microscopy

10.1101/2021.02.16.431491 ◽

2021 ◽

Author(s):

Julia R. Lazzari-Dean ◽

Evan W. Miller

Keyword(s):

Membrane Potential ◽

Fluorescence Lifetime ◽

Single Photon ◽

Photon Counting ◽

Fluorescence Lifetime Imaging ◽

Single Photon Counting ◽

Two Photon ◽

Lifetime Imaging ◽

Wide Range ◽

Relative Measurements

AbstractBackgroundMembrane potential (Vmem) exerts physiological influence across a wide range of time and space scales. To study Vmem in these diverse contexts, it is essential to accurately record absolute values of Vmem, rather than solely relative measurements.Materials & MethodsWe use fluorescence lifetime imaging of a small molecule voltage sensitive dye (VF2.1.Cl) to estimate mV values of absolute membrane potential.ResultsWe test the consistency of VF2.1.Cl lifetime measurements performed on different single photon counting instruments and find that they are in striking agreement (differences of <0.5 ps/mV in the slope and <50 ps in the y-intercept). We also demonstrate that VF2.1.Cl lifetime reports absolute Vmem under two-photon (2P) illumination with better than 20 mV of Vmem resolution, a nearly 10-fold improvement over other lifetime-based methods.ConclusionsWe demonstrate that VF-FLIM is a robust and portable metric for Vmem across imaging platforms and under both one-photon and two-photon illumination. This work is a critical foundation for application of VF-FLIM to record absolute membrane potential signals in thick tissue.

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Wide-field time-correlated single photon counting-based fluorescence lifetime imaging microscopy

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2019.162365 ◽

2019 ◽

Vol 942 ◽

pp. 162365 ◽

Cited By ~ 4

Author(s):

Klaus Suhling ◽

Liisa M. Hirvonen ◽

Wolfgang Becker ◽

Stefan Smietana ◽

Holger Netz ◽

...

Keyword(s):

Fluorescence Lifetime ◽

Single Photon ◽

Photon Counting ◽

Fluorescence Lifetime Imaging Microscopy ◽

Wide Field ◽

Fluorescence Lifetime Imaging ◽

Single Photon Counting ◽

Lifetime Imaging

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High-speed UV imaging of elves and lightning from space: first simultaneous detections from the Mini-EUSO and ASIM instruments

10.5194/egusphere-egu2020-15025 ◽

2020 ◽

Author(s):

Matteo Battisti ◽

Enrico Arnone ◽

Mario Bertaina ◽

Marco Casolino ◽

Olivier Chanrion ◽

...

Keyword(s):

Spatial Resolution ◽

High Speed ◽

Multispectral Imaging ◽

Gamma Ray ◽

Single Photon ◽

Uv Light ◽

Photon Counting ◽

Space Station ◽

Wide Field ◽

First Time

The search for the physical mechanisms of lightning, transient luminous events and terrestrial gamma-ray flashes is receiving an extraordinary support by new space observations that have recently become available. Next to lightning detectors on geostationary satellites, new low orbit experiments are giving an unprecedented insight in the very source of these processes. Looking at the physics behind these new observations requires however to have a variety of different instruments covering the same event, and this is proving extremely challenging. Here, we present observations of UV emissions of elves and lightning taken for the first time simultaneously from the two instruments Mini-EUSO and ASIM operating on the international space station. Mini-EUSO was designed to perform observations of the UV-light night emission from Earth. It is a wide field of view telescope (44&#176;x44&#176; square FOV) installed for the first time on October 2019 inside the Zvezda Module of the ISS, looking nadir through a UV transparent window. Its optical system consists of two Fresnel lenses for light collection. The light is focused onto an array of 36 multi-anode photomultiplier tubes (MAPMT), for a total of 2304 pixels. Each pixel has a footprint on ground of ~5.5 km. The instrument is capable of single-photon counting on three different timescales: a 2.5 microsecond (D1) and a 320 microsecond (D2) timescale with a dedicated trigger system, and a 40.96ms timescale (D3) used to produce a continuous monitoring of the UV emission from the Earth. ASIM is an experiment dedicated to lightning and atmospheric processes. Its Modular Multispectral Imaging Array (MMIA) is made of an array of 3 high speed photometers probing different wavelength sampling at rates up to 100 kHz, and 2 Electron Multiplication Charge Coupled Devices (EM-CCDs) with a sub-km spatial resolution with an 80&#176; FOV and recording up to 12 frames per second. Mini-EUSO detected several bright atmospheric events like lightning and elves, with a few km spatial resolution and different time resolutions, probing therefore different stages of the electromagnetic phenomena. Observations from Mini-EUSO were simultaneously captured by ASIM instruments, allowing for the first time to compare and complement the capabilities of the two instruments with a time inter-calibration based on unambiguous series of lightning detections.

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Development of new photon-counting detectors for single-molecule fluorescence microscopy

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2012.0035 ◽

2013 ◽

Vol 368 (1611) ◽

pp. 20120035 ◽

Cited By ~ 79

Author(s):

X. Michalet ◽

R. A. Colyer ◽

G. Scalia ◽

A. Ingargiola ◽

R. Lin ◽

...

Keyword(s):

Fluorescence Microscopy ◽

Single Molecule ◽

Single Photon ◽

Photon Counting ◽

Wide Field ◽

Fluorescence Lifetime Imaging ◽

Large Area ◽

Single Molecule Fluorescence ◽

Single Photon Counting ◽

Single Molecule Fluorescence Microscopy

Two optical configurations are commonly used in single-molecule fluorescence microscopy: point-like excitation and detection to study freely diffusing molecules, and wide field illumination and detection to study surface immobilized or slowly diffusing molecules. Both approaches have common features, but also differ in significant aspects. In particular, they use different detectors, which share some requirements but also have major technical differences. Currently, two types of detectors best fulfil the needs of each approach: single-photon-counting avalanche diodes (SPADs) for point-like detection, and electron-multiplying charge-coupled devices (EMCCDs) for wide field detection. However, there is room for improvements in both cases. The first configuration suffers from low throughput owing to the analysis of data from a single location. The second, on the other hand, is limited to relatively low frame rates and loses the benefit of single-photon-counting approaches. During the past few years, new developments in point-like and wide field detectors have started addressing some of these issues. Here, we describe our recent progresses towards increasing the throughput of single-molecule fluorescence spectroscopy in solution using parallel arrays of SPADs. We also discuss our development of large area photon-counting cameras achieving subnanosecond resolution for fluorescence lifetime imaging applications at the single-molecule level.

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