scholarly journals Study of Galactic Cosmic-Ray Flux Modulation by Interplanetary Plasma Structures for the Evaluation of Space Instrument Performance and Space Weather Science Investigations

Atmosphere ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 749 ◽  
Author(s):  
Catia Grimani ◽  
Daniele Telloni ◽  
Simone Benella ◽  
Andrea Cesarini ◽  
Michele Fabi ◽  
...  
Keyword(s):  
Large Scale ◽  
European Space Agency ◽  
Cosmic Ray ◽  
High Energy ◽  
Interplanetary Coronal Mass Ejections ◽  
Particle Detectors ◽  
Space Agency ◽  
Interplanetary Plasma ◽  
Galactic Cosmic Ray ◽  
Science Investigations

The role of high-energy particles in limiting the performance of on-board instruments was studied for the European Space Agency (ESA) Laser Interferometer Space Antenna (LISA) Pathfinder (LPF) and ESA/National Astronautics and Space Administration Solar Orbiter missions. Particle detectors (PD) placed on board the LPF spacecraft allowed for testing the reliability of pre-launch predictions of galactic cosmic-ray (GCR) energy spectra and for studying the modulation of proton and helium overall flux above 70 MeV n − 1 on a day-by-day basis. GCR flux variations up to approximately 15% in less than a month were observed with LPF orbiting around the Lagrange point L1 between 2016 and 2017. These variations appeared barely detected or undetected in neutron monitors. In this work the LPF data and contemporaneous observations carried out with the magnetic spectrometer AMS-02 experiment are considered to show the effects of GCR flux short-term variations with respect to monthly averaged measurements. Moreover, it is shown that subsequent large-scale interplanetary structures cause a continuous modulation of GCR fluxes. As a result, small Forbush decreases cannot be considered good proxies for the transit of interplanetary coronal mass ejections and for geomagnetic storm forecasting.

scholarly journals The theory of cosmic ray scattering on pre-existing MHD modes meets data

2021 ◽  
Vol 502 (4) ◽  
pp. 5821-5838
Author(s):  
Ottavio Fornieri ◽  
Daniele Gaggero ◽  
Silvio Sergio Cerri ◽  
Pedro De La Torre Luque ◽  
Stefano Gabici
Keyword(s):  
Diffusion Coefficients ◽  
Galactic Halo ◽  
Dominant Role ◽  
Cosmic Ray ◽  
High Energy ◽  
Scattering Rate ◽  
Equilibrium Spectrum ◽  
Galactic Cosmic Ray ◽  
Comprehensive Study ◽  
Ray Scattering

ABSTRACT We present a comprehensive study about the phenomenological implications of the theory describing Galactic cosmic ray scattering on to magnetosonic and Alfvénic fluctuations in the GeV−PeV domain. We compute a set of diffusion coefficients from first principles, for different values of the Alfvénic Mach number and other relevant parameters associated with both the Galactic halo and the extended disc, taking into account the different damping mechanisms of turbulent fluctuations acting in these environments. We confirm that the scattering rate associated with Alfvénic turbulence is highly suppressed if the anisotropy of the cascade is taken into account. On the other hand, we highlight that magnetosonic modes play a dominant role in Galactic confinement of cosmic rays up to PeV energies. We implement the diffusion coefficients in the numerical framework of the dragon code, and simulate the equilibrium spectrum of different primary and secondary cosmic ray species. We show that, for reasonable choices of the parameters under consideration, all primary and secondary fluxes at high energy (above a rigidity of $\simeq 200 \, \mathrm{GV}$) are correctly reproduced within our framework, in both normalization and slope.

scholarly journals BepiColombo Science Investigations During Cruise and Flybys at the Earth, Venus and Mercury

2021 ◽  
Vol 217 (1) ◽  
Author(s):  
Valeria Mangano ◽  
Melinda Dósa ◽  
Markus Fränz ◽  
Anna Milillo ◽  
Joana S. Oliveira ◽  
...  
Keyword(s):  
French Guiana ◽  
European Space Agency ◽  
Scientific Research ◽  
The Earth ◽  
Space Agency ◽  
Spacecraft Mission ◽  
Joint Mission ◽  
Science Investigations ◽  
Orbit Insertion ◽  
Inner Heliosphere

AbstractThe dual spacecraft mission BepiColombo is the first joint mission between the European Space Agency (ESA) and the Japanese Aerospace Exploration Agency (JAXA) to explore the planet Mercury. BepiColombo was launched from Kourou (French Guiana) on October 20th, 2018, in its packed configuration including two spacecraft, a transfer module, and a sunshield. BepiColombo cruise trajectory is a long journey into the inner heliosphere, and it includes one flyby of the Earth (in April 2020), two of Venus (in October 2020 and August 2021), and six of Mercury (starting from 2021), before orbit insertion in December 2025. A big part of the mission instruments will be fully operational during the mission cruise phase, allowing unprecedented investigation of the different environments that will encounter during the 7-years long cruise. The present paper reviews all the planetary flybys and some interesting cruise configurations. Additional scientific research that will emerge in the coming years is also discussed, including the instruments that can contribute.

scholarly journals Quantifying Horizontal and Vertical Movements in Ho Chi Minh City by Sentinel-1 Radar Interferometry

2020 ◽  
Author(s):  
Dinh Ho Tong Minh ◽  
Yen-Nhi NGO ◽  
Thu Trang Lê ◽  
Trung Chon Le ◽  
Hong Son Bui ◽  
...  
Keyword(s):  
Time Series ◽  
Large Scale ◽  
European Space Agency ◽  
Ground Subsidence ◽  
Ho Chi Minh City ◽  
Vertical Movements ◽  
Space Agency ◽  
Permanent Scatterers ◽  
The City ◽  
East West

Ho Chi Minh City (HCMC), the most populous city and the economic center of Viet Nam, has faced ground subsidence in recent decades. This work aims at providing an unprecedented spatial extent coverage of the subsidence in HCMC in both horizontal and vertical components using Interferometric Synthetic Aperture Radar (InSAR) time series. For this purpose, an advanced InSAR technique PSDS (Permanent Scatterers and Distributed Scatterers) was applied to two big European Space Agency (ESA) Sentinel-1 datasets composed of 96 ascending and 202 descending images, acquired from 2014 to 2020 over HCMC area. A time series of 33 Cosmos SkyMED images was also used for comparison purpose. The combination of ascending and descending satellite passes allows the decomposition of the light of sight velocities into horizontal East-west and vertical components. By taking into account the presence of the horizontal East-west movement, our finding indicates that the precision of the decomposed vertical velocity can be improved up to 3 mm/year for Sentinel-1 data. The obtained results revealed that subsidence is most severe in areas along the Sai Gon river in the northwest-southeast axis and the southwest of the city with the maximum value up to 80 mm/year, consistent with findings in the literature. The magnitude of horizontal East-West velocities is relatively small and a large-scale westward motion can be observed in the northwest of the city at a rate of 2-5 mm/year. Together, these results reinforced the remarkable suitability of ESA's Sentinel-1 SAR for subsidence applications even for non-Europe countries such as Vietnam and Southeast Asia.

scholarly journals Cosmic ray transport and anisotropies to high energies

2015 ◽  
Vol 2 ◽  
pp. 39-44 ◽  
Author(s):  
P. L. Biermann ◽  
L. I. Caramete ◽  
A. Meli ◽  
B. N. Nath ◽  
E.-S. Seo ◽  
...  
Keyword(s):  
Cosmic Ray ◽  
High Energy ◽  
Wave Number ◽  
Ultra High Energy ◽  
Galactic Magnetic Field ◽  
Chemical Abundances ◽  
High Energy Cosmic Rays ◽  
High Energies ◽  
Isotropic Approximation ◽  
Galactic Cosmic Ray

Abstract. A model is introduced, in which the irregularity spectrum of the Galactic magnetic field beyond the dissipation length scale is first a Kolmogorov spectrum k-5/3 at small scales λ = 2 π/k with k the wave-number, then a saturation spectrum k-1, and finally a shock-dominated spectrum k-2 mostly in the halo/wind outside the Cosmic Ray disk. In an isotropic approximation such a model is consistent with the Interstellar Medium (ISM) data. With this model we discuss the Galactic Cosmic Ray (GCR) spectrum, as well as the extragalactic Ultra High Energy Cosmic Rays (UHECRs), their chemical abundances and anisotropies. UHECRs may include a proton component from many radio galaxies integrated over vast distances, visible already below 3 EeV.

scholarly journals Six years of total ozone column measurements from SCIAMACHY nadir observations

2009 ◽  
Vol 2 (1) ◽  
pp. 87-98 ◽  
Author(s):  
C. Lerot ◽  
M. Van Roozendael ◽  
J. van Geffen ◽  
J. van Gent ◽  
C. Fayt ◽  
...  
Keyword(s):  
Cross Sections ◽  
Total Ozone ◽  
Large Scale ◽  
European Space Agency ◽  
Data Sets ◽  
Data Set ◽  
Ozone Data ◽  
Space Agency ◽  
German Aerospace ◽  
The Impact

Abstract. Total O3 columns have been retrieved from six years of SCIAMACHY nadir UV radiance measurements using SDOAS, an adaptation of the GDOAS algorithm previously developed at BIRA-IASB for the GOME instrument. GDOAS and SDOAS have been implemented by the German Aerospace Center (DLR) in the version 4 of the GOME Data Processor (GDP) and in version 3 of the SCIAMACHY Ground Processor (SGP), respectively. The processors are being run at the DLR processing centre on behalf of the European Space Agency (ESA). We first focus on the description of the SDOAS algorithm with particular attention to the impact of uncertainties on the reference O3 absorption cross-sections. Second, the resulting SCIAMACHY total ozone data set is globally evaluated through large-scale comparisons with results from GOME and OMI as well as with ground-based correlative measurements. The various total ozone data sets are found to agree within 2% on average. However, a negative trend of 0.2–0.4%/year has been identified in the SCIAMACHY O3 columns; this probably originates from instrumental degradation effects that have not yet been fully characterized.

Dayside Magnetopause Reconnection and Flux Transfer Events: BepiColombo Earth-Flyby

2021 ◽  
Author(s):  
Wei-Jie Sun ◽  
James Slavin ◽  
Rumi Nakamura ◽  
Daniel Heyner ◽  
Johannes Mieth
Keyword(s):  
Magnetic Field ◽  
Large Scale ◽  
European Space Agency ◽  
Flux Rope ◽  
Transfer Event ◽  
Flux Transfer Events ◽  
Space Agency ◽  
Flux Ropes ◽  
Flux Transfer ◽  
Magnetospheric Multiscale Mission

<p>BepiColombo is a joint mission of the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) to the planet Mercury. The BepiColombo mission consists of two spacecraft, which are the Mercury Planetary Orbiter (MPO) and Mercury Magnetospheric Orbiter (Mio). The mission made its first planetary flyby, which is the only Earth flyby, on 10 April 2020, during which several instruments collected measurements. In this study, we analyze MPO magnetometer (MAG) observations of Flux Transfer Events (FTEs) in the magnetosheath and the structure of the subsolar magnetopause near the  flow stagnation point. The magnetosheath plasma beta was high with a value of ~ 8 and the interplanetary magnetic field (IMF) was southward with a clock angle that decreased from ~ 100 degrees to ~ 150 degrees.  As the draped IMF became increasingly southward several of the flux transfer event (FTE)-type flux ropes were observed. These FTEs traveled southward indicating that the magnetopause X-line was located northward of the spacecraft, which is consistent with a dawnward tilt of the IMF. Most of the FTE-type flux ropes were in ion-scale, <10 s duration, suggesting that they were newly formed. Only one large-scale FTE-type flux rope, ~ 20 s, was observed. It was made up of two successive bipolar signatures in the normal magnetic field component, which is evidence of coalescence at a secondary reconnection site. Further analysis demonstrated that the dimensionless reconnection rate of the re-reconnection associated with the coalescence site was ~ 0.14. While this investigation was limited to the MPO MAG observations, it strongly supports a key feature of dayside reconnection discovered in the Magnetospheric Multiscale mission, the growth of FTE-type flux ropes through coalescence at secondary reconnection sites.</p>

scholarly journals Impact of Cosmic-Ray Physics on Dark Matter Indirect Searches

2018 ◽  
Vol 2018 ◽  
pp. 1-23 ◽  
Author(s):  
Daniele Gaggero ◽  
Mauro Valli
Keyword(s):  
Dark Matter ◽  
Cosmic Ray ◽  
High Energy ◽  
Research Field ◽  
Current Data ◽  
Weakly Interacting Massive Particles ◽  
Beyond The Standard Model ◽  
High Energy Astrophysics ◽  
Classical Plasma ◽  
Galactic Cosmic Ray

The quest for the elusive dark matter (DM) that permeates the Universe (and in general the search for signatures of physics beyond the Standard Model at astronomical scales) provides a unique opportunity and a tough challenge to the high energy astrophysics community. In particular, the so-called DMindirect searches—mostly focused on a class of theoretically well-motivated DM candidates such as the weakly interacting massive particles—are affected by a complex astrophysical background of cosmic radiation. The understanding and modeling of such background require a deep comprehension of an intricate classical plasma physics problem, i.e., the interaction between high energy charged particles, accelerated in peculiar astrophysical environments, and magnetohydrodynamic turbulence in the interstellar medium of our galaxy. In this review we highlight several aspects of this exciting interplay between the most recent claims of DM annihilation/decay signatures from the sky and the galactic cosmic-ray research field. Our purpose is to further stimulate the debate about viable astrophysical explanations, discussing possible directions that would help breaking degeneracy patterns in the interpretation of current data. We eventually aim to emphasize how a deep knowledge on the physics of CR transport is therefore required to tackle the DM indirect search program at present and in the forthcoming years.

scholarly journals On the flux of high-energy cosmogenic neutrinos and the influence of the extragalactic magnetic field

2019 ◽  
Vol 488 (1) ◽  
pp. L119-L122 ◽  
Author(s):  
David Wittkowski ◽  
Karl-Heinz Kampert
Keyword(s):  
Magnetic Field ◽  
Cosmic Rays ◽  
Large Scale ◽  
Neutrino Flux ◽  
Cosmic Ray ◽  
High Energy ◽  
Observation Time ◽  
Cosmological Time ◽  
Cosmic Background ◽  
The Universe

ABSTRACT Cosmogenic neutrinos originate from interactions of cosmic rays propagating through the universe with cosmic background photons. Since both high-energy cosmic rays and cosmic background photons exist, the existence of high-energy cosmogenic neutrinos is certain. However, their flux has not been measured so far. Therefore, we calculated the flux of high-energy cosmogenic neutrinos arriving at the Earth on the basis of elaborate 4D simulations that take into account three spatial degrees of freedom and the cosmological time-evolution of the universe. Our predictions for this neutrino flux are consistent with the recent upper limits obtained from large-scale cosmic-ray experiments. We also show that the extragalactic magnetic field has a strong influence on the neutrino flux. The results of this work are important for the design of future neutrino observatories, since they allow to assess the detector volume and observation time that are necessary to detect high-energy cosmogenic neutrinos in the near future. An observation of such neutrinos would push multimessenger astronomy to hitherto unachieved energy scales.

scholarly journals RADIODETECTION OF COSMIC RAY EXTENSIVE AIR SHOWERS: UPGRADE OF THE CODALEMA EXPERIMENT

2005 ◽  
Vol 20 (29) ◽  
pp. 6869-6871 ◽  
Author(s):  
D. ARDOUIN ◽  
A. BELLETOILE ◽  
D. CHARRIER ◽  
R. DALLIER ◽  
L. DENIS ◽  
...  
Keyword(s):  
Antenna Array ◽  
Background Level ◽  
Cosmic Ray ◽  
High Energy ◽  
Extensive Air Showers ◽  
Ultra High Energy ◽  
Air Showers ◽  
Particle Detectors ◽  
Demonstration Experiment ◽  
And Performance

We present the characteristics and performance of a demonstration experiment devoted to the observation of ultra high-energy cosmic ray extensive air showers using a radiodetection technique. In a first step, one antenna narrowed band filtered acting as trigger, with a 4σ threshold above sky background-level, was used to tag any radio transient in coincidence on the antenna array. Recently, the addition of 4 particle detectors has allowed us to observe cosmic ray events in coincidence with antennas.

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