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Radiative capture of proton through the ^(14)N(p,γ)^(15)O reaction at low energy

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Chinese Physics C 2024年第4期48卷 183-192页

作者： B.F.Irgaziev Abdul Kabir Jameel-Un Nabi National University of Uzbekistan Tashkent 100174Uzbekistan space and Astrophysics Research lab National Centre of GIS and Space ApplicationsDepartment of Space ScienceInstitute of Space TechnologyIslamabad 44000Pakistan University of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

The CNO cycle is the main source of energy in stars more massive than our *** process defines the energy production,the duration of which can be used to determine the lifetime of massive *** cycle is an important tool for determining the age of globular *** proton capture via p+^(14)N→^(15)O+γ,at energies of astrophysical interest,is an important process in the CNO *** this project,we apply a potential model to describe both non-resonant and resonant reactions in the channels where radiative capture occurs through electric E1 *** employed the R-matrix method to describe the ongoing reactions via M1 resonant transitions,when it was not possible to correctly reproduce the experimental data using the potential *** partial components of the astrophysical S-factor are calculated for all possible electric and magnetic dipole transitions in ^(15)*** linear extrapolated S-factor at zero energy(S(0))agrees well with earlier reported values for all transition types considered in this *** on the value of the total astrophysical S-factor,depending on the collision energy,we calculate the nuclear reaction rates for p+^(14)N→^(15)O+γ.The computed rates agree well with the results reported in the NACRE II Collaboration and most recent existing measurements.

关键词： CNO cycle potential model R-matrix method cross-section astrophysical S-factor nuclear rates.

Fluidization and Transport of Vibrated Granular Matter:A Review of Landmark and Recent Contributions

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Fluid Dynamics & Materials Processing 2024年第1期20卷 1-29页

作者： Peter Watson Sebastien Vincent Bonnieu Marcello Lappa Department of Mechanical and Aerospace Engineering University of StrathclydeGlasgowUK European space Agency European Space Research and Technology CentreNoordwijkNetherland

We present a short retrospective review of the existing literature about the dynamics of(dry)granular matter under the effect of *** main objective is the development of an integrated resource where vital information about past findings and recent discoveries is provided in a single *** attention is paid to those works where successful synthetic routes to as-yet unknown phenomena were *** landmark results are analyzed,while smoothly blending them with a history of the field and introducing possible categorizations of the prevalent *** no classification is perfect,and it is hard to distillate general properties out of specific observations or realizations,two possible ways to interpret the existing results are defined according to the type of forcing or the emerging(ensuing)regime of *** particular,first results concerning the case where vibrations and gravity are concurrent(vertical shaking)are examined,then the companion situation with vibrations perpendicular to gravity(horizontal shaking)is *** classes are introduced as follows:(1)Regimes where sand self-organizes leading to highly regular geometrical“pulsating”patterns(thin layer case);(2)Regimes where the material undergoes“fluidization”and develops an internal multicellular convective state(tick layers case);(3)Regimes where the free interface separating the sand from the overlying gas changes inclination or develops a kind a patterned configuration consisting of stable valleys and mountains or travelling waves;(4)Regimes where segregation is produced,i.e.,particles of a given size tend to be separated from the other grains(deep containers).Where possible,an analogy or parallelism is drawn with respect to the companion field of fluid-dynamics for which the assumption of“continuum”can be applied.

关键词： Granular materials vibrations fluidization flowability symmetry breaking

Magnetopause properties at the dusk magnetospheric flank from global magnetohydrodynamic simulations,the kinetic Vlasov equilibrium,and in situ observations--Potential implications for SMILE

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Earth and Planetary Physics 2024年第1期8卷 222-233页

作者： Marius Echim Costel Munteanu Gabriel Voitcu Eliza Teodorescu Institute of space Science Măgurele 077125Romania Royal Belgian Institute for space Aeronomy 1180 BrusselsBelgium Solar-Terrestrial centre of Excellence(STCE) 1180 BrusselsBelgium

We derived the properties of the terrestrial magnetopause(MP)from two modeling approaches,one global–fluid,the other local–kinetic,and compared the results with data collected in situ by the Magnetospheric Multiscale 2(MMS2)*** used global magnetohydrodynamic(MHD)simulations of the Earth’s magnetosphere(publicly available from the NASA-CCMC[National Aeronautics and space Administration–Community Coordinated Modeling Center])and local Vlasov equilibrium models(based on kinetic models for tangential discontinuities)to extract spatial profiles of the plasma and field variables at the Earth’s *** global MHD simulations used initial solar wind conditions extracted from the OMNI database at the time epoch when the MMS2 observes the *** kinetic Vlasov model used asymptotic boundary conditions derived from the same in situ MMS measurements upstream or downstream of the *** global MHD simulations provide a three-dimensional image of the magnetosphere at the time when the MMS2 crosses the *** Vlasov model provides a one-dimensional local view of the MP derived from first principles of kinetic *** MMS2 experimental data also serve as a reference for comparing and validating the numerical simulations and *** found that the MP transition layer formed in global MHD simulations was generally localized closer to the Earth(roughly by one Earth radius)from the position of the real MP observed by the *** also found that the global MHD simulations overestimated the thickness of the MP transition by one order of magnitude for three analyzed variables:magnetic field,density,and tangential *** MP thickness derived from the local Vlasov equilibrium was consistent with observations for all three of these *** overestimation of density in the Vlasov equilibrium was reduced compared with the global MHD *** discuss our results in the context of future SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)campaigns for observing

关键词： magnetopause magnetohydrodynamic numerical simulations Vlasov equilibrium Magnetospheric Multiscale observations

A high-order target phase approach for the station-keeping of periodic orbits

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Astrodynamics 2024年第1期8卷 61-75页

作者： Xiaoyu Fu Nicola Baresi Roberto Armellin Surrey space centre University of SurreyGuildfordGU27XHUK Te PūnahaĀtea-Auckland space Institute University of AucklandAuckland1010New Zealand

A novel high-order target phase approach(TPhA)for the station-keeping of periodic orbits is proposed in this *** key elements of the TPhA method,the phase-angle Poincare map and high-order maneuver map,are constructed using differential algebra(DA)techniques to determine station-keeping epochs and calculate correction maneuvers.A stochastic optimization framework tailored for the TPhA-based station-keeping process is leveraged to search for fuel-optimal and error-robust TPhA ***-satellite orbits(QSOs)around Phobos are investigated to demonstrate the efficacy of TPhA in mutli-fidelity dynamical *** Carlo simulations demonstrated that the baseline QSO of JAXA’s Martian Moons eXploration(MMX)mission could be maintained with a monthly maneuver budget of approximately 1 m/s.

关键词： target phase approach(TPhA) station-keeping Poincarémap differential algebra(DA) quasi-satellite orbit(QSO)

Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： M.Grandin H.K.Connor S.Hoilijoki M.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis M.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NASA Goddard space Flight Center GreenbeltMD20771USA space and Earth Observation centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing *** Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)*** earlier modeling works have already simulated soft X-ray images as might be obtained by SMILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic *** first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray *** instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this ***,a proton density increase by 14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation SMILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

Performance validation of High Mountain Asia 8-meter Digital Elevation Model using ICESat-2 geolocated photons

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Journal of Mountain Science 2024年第8期21卷 2562-2578页

作者： Giribabu DANDABATHULA Subham ROY Omkar Shashikant GHATAGE Vaibhav Balaso KOLASE Shwetambari SATPUTE Koushik GHOSH Sahibnoor KAUR Satyanarayana PONDARI Apurba Kumar BERA Sushil Kumar SRIVASTAV Regional Remote Sensing centre-West National Remote Sensing CentreIndian Space Research OrganisationJodhpur 342005India Department of Geography School of Earth SciencesBharathidasan UniversityTiruchirappalli 620024India centre for Climate Change and Water Research Suresh Gyan Vihar UniversityJaipur 302017India Department of Geography Panjab UniversityChandigarh 160014India National Remote Sensing centre Indian Space Research OrganisationHyderabad 500037India Regional centres National Remote Sensing CentreIndian Space Research OrganisationNew Delhi 110049India

High Mountain Asia(HMA),recognized as a third pole,needs regular and intense studies as it is susceptible to climate *** accurate and high-resolution Digital Elevation Model(DEM)for this region enables us to analyze it in a 3D environment and understand its intricate role as the Water Tower of *** science teams of NASA realized an 8-m DEM using satellite stereo imagery for HMA,termed HMA 8-m *** this research,we assessed the vertical accuracy of HMA 8-m DEM using reference elevations from ICESat-2 geolocated photons at three test sites of varied topography and land *** were made from statistical quantifiers and elevation *** the world’s highest mountain,Mount Everest,and its surroundings,Root Mean Squared Error(RMSE)and Mean Absolute Error(MAE)resulted in 1.94 m and 1.66 m,respectively;however,a uniform positive bias observed in the elevation profiles indicates the seasonal snow cover change will dent the accurate estimation of the elevation in this sort of test *** second test site containing gentle slopes with forest patches has exhibited the Digital Surface Model(DSM)features with RMSE and MAE of 0.58 m and 0.52 m,*** third test site,situated in the Zanda County of the Qinghai-Tibet,is a relatively flat terrain bed,mostly bare earth with sudden river cuts,and has minimal errors with RMSE and MAE of 0.32 m and 0.29 m,respectively,and with a negligible ***,in one more test site,the feasibility of detecting the glacial lakes was tested,which resulted in exhibiting a flat surface over the surface of the lakes,indicating the potential of HMA 8-m DEM for deriving the hydrological *** results accrued in this investigation confirm that the HMA 8-m DEM has the best vertical accuracy and should be of high use for analyzing natural hazards and monitoring glacier surfaces.

关键词： High Mountain Asia Digital Elevation Model ICESat-2 geolocated photons Accuracy assessment

Study of Secondary Cosmic Rays and Astronomical X-Ray Sources using Small Stratospheric Balloons

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Research in Astronomy and Astrophysics 2024年第6期24卷 94-109页

作者： Rupnath Sikdar Sandip K.Chakrabarti Debashis Bhowmick Indian centre for space Physics 466BarakholaSingabari RoadNetai NagarKolkata700099West BengalIndia

The X-ray sources of the universe are extraterrestrial in nature which emit X-ray *** closest strong X-ray source is the Sun,which is followed by various compact sources such as neutron stars,black holes,the Crab pulsar,*** this paper,we analyze the data received from several low-cost lightweight meteorological balloon-borne missions launched by the Indian centre for space *** main interest is to study the variation of the vertical intensity of secondary cosmic rays,the detection of strong X-ray sources,and their spectra in the energy band of^(1)0–80 keV during the complete *** to the lack of an onboard pointing system,low exposure time,achieving a maximum altitude of only~42 km,and freely rotating the payload about its axis,we modeled the background radiation flux for the X-ray detector using physical *** also present the source detection method,observation of the pulsation of the Crab(^(3)3 Hz),and spectra of some sources such as the quiet Sun and the Crab pulsar.

关键词： X-rays:stars balloons instrumentation:detectors

Recent Progress of the Solar Wind Magnetosphere Ionosphere Link Explorer (SMILE) Mission

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空间科学学报 2024年第4期44卷 692-698页

作者： WANG Chi ESCOUBET Philippe FORSYTH Colin LI Jing AGNOLON David State Key Laboratory of space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190 European space Agency/European space Research and Technology centre Noordwijk 2201 AZ Mullard space Science Laboratory University College LondonLondon RH56 NT

The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the Chinese Academy of Sciences(CAS)and the European space Agency(ESA),aiming to understand the interaction of the solar wind with the Earth’s magnetosphere in a global *** of May 2024,the SMILE mission is in phase-D with an expected launch date of September *** report summarizes developments in the mission during the past two years.

关键词： SMILE Soft X-ray Imager Ultra-Violet Imager Light Ion Analyzer Magnetometer

Acceleration of solar wind particles due to inertial Alfvén waves

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Communications in Theoretical Physics 2024年第6期76卷 137-141页

作者： Kiran Batool Imran A Khan M Shamir Abdul Kabir S Ayaz Theoretical Physics Department National Centre for PhysicsIslamabad 44000Pakistan Department of space Sciences Institute of Space TechnologyIslamabad 44000Pakistan space and Astrophysics Research Lab(SARL) National Center of GIS and Space Applications(NCGSA)Islamabad 44000Pakistan Salam Chair Department of PhysicsGC University LahoreKatchery RoadLahorePunjab 54000Pakistan Department of space Science and CSPAR University of Alabama in HuntsvilleHuntsvilleAL 35899United States of America

Gaining an understanding of the effects and dynamics of the solar wind is crucial for the study of space weather,Earth's magnetosphere,spacecraft protection,the dynamics of the Solar System,and various other *** show that Alfvén waves effectively transfer energy to resonant *** study demonstrates how inertial Alfvén waves deliver their energy to resonant plasma particles in different solar environments under certain *** analysis shows that inertial Alfvén waves experience more rapid damping with increasing parallel wavenumber,ambient magnetic field strength,and particle number density,coupled with a decrease in *** rate of energy transfer to resonant particles intensifies with higher temperatures and reduced parallel wavenumber and particle number *** with higher initial velocities actively participate in Landau damping,especially in regions with a stronger ambient magnetic field.

关键词： solar wind inertial Alfven waves resonant particles