Spectroscopy of gamma-rays of Earth, Venus and Mercury: MGNS instrument onboard BepiColombo mission

The Mercurian Gamma-ray and Neutron Spectrometer (MGNS) is a scientific instrument developed to study the elementary composition of the Mercury&#8217;s sub-surface by measurements of neutron and gamma-ray emission of the planet. MGNS measures neutron fluxes in a wide energy range from thermal energy up to 10 MeV and gamma-rays in the energy range of 300 keV up to 10 MeV with the energy resolution of 5% FWHM at 662 keV and of 2% at 8 MeV. The innovative crystal of CeBr3 is used for getting such a good energy resolution for a scintillation detector of gamma-rays. During the BC long cruise to Mercury, it is planned that the MGNS instrument will operate practically continuously to perform measurements of neutrons and gamma-ray fluxes for achieving two main goals of investigations. The first goal is monitoring of the local radiation background of the prompt spacecraft emission due to bombardment by energetic particles of Galactic Cosmic Rays. This data will be taken into account at the mapping phase of the mission on the orbit around Mercury. Detailed knowledge of the spacecraft background radiation during the cruise will help to derive the data for neutron and gamma-ray emission of the planet at the mapping stage of the mission because many elements, like Mg, Na, O and others, the abundance of which at the uppermost layer of the planet is studied, are also present in the material of the spacecraft. Indeed, the nuclear lines of Al, Mg and O are well-pronounced in the spectrum, which are also expected to be detectable in the gamma-ray spectrum of the Mercury emission. The second goal of MGNS cruise operations is the participation in the Inter Planetary Network (IPN) program for the localization of sources of Gamma-Ray Bursts in the sky. In fact, the localization accuracy by the interplanetary triangulation technique is inversely proportional to the distance between the spacecrafts that jointly detected a GRB. Before the launch of BepiColombo, the IPN network included a group of spacecrafts in the near-to-Earth orbit (e.g. Konus-Wind, Fermi-GBM, INTEGRAL, Insight-HXMT) and the Mars Odyssey spacecraft on the orbit around Mars. Now, MGNS provides another interplanetary location, potentially increasing the accuracy of GRBs localization. During the first 13 months of continuous operation, MGNS detected 24 GRB's. Pre-set value of time resolution for continuous measurements of profiles of GRBs is 20 seconds. Since of November 14, 2019, the BC Mission Operation Centre has allocated downlink resources to run MGNS continuously in a 1 sec time resolution for GRB measurements. The GRB detection rate, based on data with a time resolution of 1 sec is about 2-3 GRB's per month. Gamma-rays of solar flares are also detectable by MGNS. Solar flares are nonstationary and anisotropic processes and the ability to observe them from different directions in the Solar system is crucial for further understanding their developments and propagation, as it was demonstrated in the case of HEND instrument on board Mars Odyssey. The Sun cycle is presently around its minimum, and MGNS has not detected any solar events during its first 7 months of the cruise, but the flight to Mercury is long enough and many future flares are expected to be detected. The MGNS instrument will also perform special sessions of measurements during flybys of Earth, Venus and Mercury with the objective to measure neutron and gamma-ray albedo of the upper atmosphere of Earth and Venus and of the surface of Mercury. Another objective is to test the computational model of the local background of the spacecraft using the data measured at different orbital phases of flyby trajectories. The low altitude flybys (such as the 700 km flyby for Venus and three 200 km flybys for Mercury) would be the most useful for such tests being BC maximally shadowed for cosmic radiation by the actual planet. Neutron and gamma-ray measurements during Earth flybys enable investigation of interaction between solar wind and Earth environments as well as studies of spacecraft neutron and gamma-ray background upon its passage through the Earth's radiation belts.

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Solar Flare Energetic Neutral Emission Measurements in the Project Coronas-I

International Astronomical Union Colloquium ◽

10.1017/s0252921100026208 ◽

1994 ◽

Vol 144 ◽

pp. 635-639

Author(s):

J. Baláž ◽

A. V. Dmitriev ◽

M. A. Kovalevskaya ◽

K. Kudela ◽

S. N. Kuznetsov ◽

...

Keyword(s):

Solar Flare ◽

Energy Range ◽

Gamma Rays ◽

Pulse Shape ◽

Gamma Ray ◽

Pulse Shape Discrimination ◽

Shape Discrimination ◽

Solar Neutron ◽

Low Altitude

AbstractThe experiment SONG (SOlar Neutron and Gamma rays) for the low altitude satellite CORONAS-I is described. The instrument is capable to provide gamma-ray line and continuum detection in the energy range 0.1 – 100 MeV as well as detection of neutrons with energies above 30 MeV. As a by-product, the electrons in the range 11 – 108 MeV will be measured too. The pulse shape discrimination technique (PSD) is used.

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Design of an ultrahigh-energy-resolution and wide-energy-range soft X-ray beamline

Journal of Synchrotron Radiation ◽

10.1107/s1600577513029093 ◽

2013 ◽

Vol 21 (1) ◽

pp. 273-279 ◽

Cited By ~ 9

Author(s):

L. Xue ◽

R. Reininger ◽

Y.-Q. Wu ◽

Y. Zou ◽

Z.-M. Xu ◽

...

Keyword(s):

Energy Range ◽

Energy Resolution ◽

Wide Energy Range ◽

Ultrahigh Energy ◽

Exit Slit ◽

Shanghai Synchrotron Radiation Facility ◽

X Ray ◽

Variable Line ◽

Line Spacing ◽

Wide Energy

A new ultrahigh-energy-resolution and wide-energy-range soft X-ray beamline has been designed and is under construction at the Shanghai Synchrotron Radiation Facility. The beamline has two branches: one dedicated to angle-resolved photoemission spectroscopy (ARPES) and the other to photoelectron emission microscopy (PEEM). The two branches share the same plane-grating monochromator, which is equipped with four variable-line-spacing gratings and covers the 20–2000 eV energy range. Two elliptically polarized undulators are employed to provide photons with variable polarization, linear in every inclination and circular. The expected energy resolution is approximately 10 meV at 1000 eV with a flux of more than 3 × 1010 photons s−1at the ARPES sample positions. The refocusing of both branches is based on Kirkpatrick–Baez pairs. The expected spot sizes when using a 10 µm exit slit are 15 µm × 5 µm (horizontal × vertical FWHM) at the ARPES station and 10 µm × 5 µm (horizontal × vertical FWHM) at the PEEM station. The use of plane optical elements upstream of the exit slit, a variable-line-spacing grating and a pre-mirror in the monochromator that allows the influence of the thermal deformation to be eliminated are essential for achieving the ultrahigh-energy resolution.

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TARANIS XGRE and IDEE Detection Capability of Terrestrial Gamma-Ray Flashes and Associated Electron Beams

10.5194/gi-2017-1 ◽

2017 ◽

Cited By ~ 1

Author(s):

David Sarria ◽

Francois Lebrun ◽

Pierre-Louis Blelly ◽

Remi Chipaux ◽

Philippe Laurent ◽

...

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Energy Range ◽

Gamma Rays ◽

Gamma Ray ◽

Electron Beams ◽

Effective Area ◽

Detection Rates ◽

Transient Phenomena ◽

Preliminary Model

Abstract. With a launch expected in 2018, the TARANIS micro-satellite is dedicated to the study of transient phenomena observed in association with thunderstorms. On-board the spacecraft, XGRE and IDEE are two instruments dedicated to study Terrestrial Gamma-ray Flashes (TGFs) and associated electron beams (TEBs). XGRE can detect electrons (energy range: 1 MeV to 10 MeV) and X/gamma-rays (energy range: 20 keV to 10 MeV), with a very high counting capability (about 10 million counts per second), and the ability to discriminate one type of particle from the other. The IDEE instrument is focused on electrons in the 80 keV to 4 MeV energy range, with the ability to estimate their pitch angles. Monte-Carlo simulations of the TARANIS instruments, using a preliminary model of the spacecraft, allow sensitive area estimates for both instruments. It leads to an averaged effective area of 425 cm2 for XGRE to detect X/gamma rays from TGFs, and the combination of XGRE and IDEE gives an average effective area of 255 cm2 to detect electrons/positrons from TEBs. We then compare these performances to RHESSI, AGILE, and Fermi GBM, using performances extracted from literature for the TGF case, and with the help of Monte-Carlo simulations of their mass models for the TEB case. Combining these data with with the help of the MC-PEPTITA Monte-Carlo simulations of TGF propagation in the atmosphere, we build a self-consistent model of the TGF and TEB detection rates of RHESSI, AGILE, and Fermi. It can then be used to estimate that TARANIS should detect about 225 TGFs/year and 25 TEBs/year.

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Ground-based Gamma-ray Astronomy

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000025637 ◽

1993 ◽

Vol 10 (3) ◽

pp. 183-188 ◽

Cited By ~ 1

Author(s):

R.W. Clay ◽

B.R. DawSOn

Keyword(s):

Energy Range ◽

Present State ◽

Gamma Rays ◽

Gamma Ray ◽

Signal To Noise ◽

Gamma Ray Astronomy ◽

The Past

AbstractGround-based gamma-ray astronomy has slowly developed over the past quarter of a century to a position now where a number of sources are known to produce gamma-rays in the energy range 1011eV to 1018eV. The observations are difficult, with exceptional signal to noise problems, but improved techniques are now allowing observers to proceed with confidence. In this paper the physical bases of the observations are emphasised to show the important issues in the field and the present state of the observations is indicated.

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GAMMA RAYS STUDIES BASED ON ATMOSPHERIC CHERENKOV TECHNIQUE AT HIGH MOUNTAIN ALTITUDE

International Journal of Modern Physics A ◽

10.1142/s0217751x05030727 ◽

2005 ◽

Vol 20 (29) ◽

pp. 7016-7019 ◽

Cited By ~ 2

Author(s):

A. MISHEV ◽

S. MAVRODIEV ◽

J. STAMENOV

Keyword(s):

Energy Range ◽

Gamma Rays ◽

Gamma Ray ◽

Light Flux ◽

Extensive Air Showers ◽

Cherenkov Light ◽

High Mountain ◽

Flux Analysis ◽

Air Showers ◽

Gamma Ray Astronomy

We present a new method for ground based gamma ray astronomy based only on atmospheric Cherenkov light flux analysis. The Cherenkov light flux densities in extensive air showers initiated by different primaries are simulated in the energy range 100 GeV – 100 PeV for different primaries using the CORSIKA 6.003 code at (536 g/cm2). An approximation of lateral distribution of Cherenkov light flux densities in EAS is obtained using a nonlinear fit such as Breit-Wigner. The simulated and reconstructed events are compared and the accuracy in energy and primary mass reconstruction are obtained.

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Gamma-ray production in the 170Er(p,n)170Tm nuclear reaction

Open Physics ◽

10.2478/s11534-009-0157-y ◽

2010 ◽

Vol 8 (4) ◽

Author(s):

Alexandru Mihailescu ◽

Gheorghe Cata-Danil

Keyword(s):

High Resolution ◽

Energy Range ◽

Nuclear Reaction ◽

Gamma Rays ◽

Compound Nucleus ◽

Beam Energy ◽

Gamma Ray ◽

Excitation Functions ◽

Γ Ray ◽

First Time

AbstractFor the first time discrete gamma-rays following the nuclear reaction 170Er(p,n)170Tm with enriched target were measured with a high resolution GeHP spectrometer. Protons delivered by the Bucharest FN Tandem Van de Graaff accelerator bombarded a thin self-supporting film of enriched erbium. Measured γ-ray energies (Eγ), their relative intensities (Iγ) and corresponding excitation functions for the beam energy range 2.0–3.6 MeV are reported in the present work. The measured excitation functions were fairly well reproduced by compound nucleus calculations based on the Hauser-Feshbach formalism.

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SEARCH FOR DARK MATTER WITH GAMMA-RAYS: A REVIEW

Acta Polytechnica ◽

10.14311/ap.2013.53.0545 ◽

2013 ◽

Vol 53 (A) ◽

pp. 545-549 ◽

Cited By ~ 1

Author(s):

Aldo Morselli

Keyword(s):

Dark Matter ◽

Energy Range ◽

Gamma Rays ◽

Gamma Ray ◽

High Energy ◽

Space Telescope ◽

High Energy Gamma ◽

Astrophysical Objects ◽

Energy Gamma

Successfully launched in June 2008, the Fermi Gamma-ray Space Telescope, formerly named GLAST, has been observing the high-energy gamma-ray sky with unprecedented sensitivity in the 20MeV ÷ 300 GeV energy range and electrons + positrons in the 7 GeV ÷ 1TeV range, opening a new observational window on a wide variety of astrophysical objects.

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Gamma-rays from SS433: evidence for periodicity

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz559 ◽

2019 ◽

Vol 485 (2) ◽

pp. 2970-2975 ◽

Cited By ~ 8

Author(s):

Kajwan Rasul ◽

Paula M Chadwick ◽

Jamie A Graham ◽

Anthony M Brown

Keyword(s):

Energy Range ◽

Photon Energy ◽

Gamma Rays ◽

Gamma Ray ◽

Temporal Analysis ◽

Photon Energy Range ◽

X Ray ◽

Relativistic Jet ◽

Gamma Ray Emission

ABSTRACT In this paper we present our study of the gamma-ray emission from the microquasar SS433. Integrating over 9 yr of Fermi-LAT Pass 8 data, we detect SS433 with a significance of ∼13σ in the 200 to 500 MeV photon energy range, with evidence for an extension in the direction of the w1 X-ray ‘hotspot’. A temporal analysis reveals evidence for modulation of SS433’s gamma-ray emission with the precession period of its relativistic jet. This suggests that at least some of SS433’s gamma-ray emission originates close to the object rather than from the jet termination regions.

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Centaurus A at Hard X-Rays and Soft Gamma-Rays

Publications of the Astronomical Society of Australia ◽

10.1071/as09070 ◽

2010 ◽

Vol 27 (4) ◽

pp. 431-438 ◽

Cited By ~ 8

Author(s):

H. Steinle

Keyword(s):

Energy Range ◽

Spatial Resolution ◽

Gamma Rays ◽

Gamma Ray ◽

Spectral Energy Distribution ◽

High Energy ◽

Spectral Energy ◽

X Rays ◽

Satellite Mission ◽

X Ray

AbstractCen A, at a distance of less than 4 Mpc, is the nearest radio-loud AGN. Its emission is detected from radio to very-high energy gamma-rays. Despite the fact that Cen A is one of the best studied extragalactic objects the origin of its hard X-ray and soft gamma-ray emission (100 keV <E< 50 MeV) is still uncertain. Observations with high spatial resolution in the adjacent soft X-ray and hard gamma-ray regimes suggest that several distinct components such as a Seyfert-like nucleus, relativistic jets, and even luminous X-ray binaries within Cen A may contribute to the total emission in the MeV regime that has been detected with low spatial resolution. As the Spectral Energy Distribution of Cen A has its second maximum around 1 MeV, this energy range plays an important role in modeling the emission of (this) AGN. As there will be no satellite mission in the near future that will cover this energies with higher spatial resolution and better sensitivity, an overview of all existing hard X-ray and soft gamma-ray measurements of Cen A is presented here defining the present knowledge on Cen A in the MeV energy range.

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