J/MNRAS/519/1503ivo://CDS.VizieR/J/MNRAS/519/1503doi:10.26093/cds/vizier.75191503CDSSampson M.Beattie J.R.Krumholz M.R.Crocker R.M.Federrath C.Seta A.2024-11-06T20:34:39Z2024-05-03T09:55:48ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frastronomical-modelsCosmic rays (CRs) are a dynamically important component of the interstellar medium (ISM) of galaxies. The ~GeV CRs that carry most CR energy and pressure are likely confined by self-generated turbulence, leading them to stream along magnetic field lines at the ion Alfven speed. However, the consequences of self-confinement for CR propagation on galaxy scales remain highly uncertain. In this paper, we use a large ensemble of magnetohydrodynamical turbulence simulations to quantify how the basic parameters describing ISM turbulence - the sonic Mach number, M (plasma compressibility), Alfven Mach number, M_A0_(strength of the large-scale field with respect to the turbulence), and ionization fraction by mass, {chi} - affect the transport of streaming CRs. We show that the large-scale transport of CRs whose small-scale motion consists of streaming along field lines is well described as a combination of streaming along the mean field and superdiffusion both along (parallel to) and across (perpendicular to) it; M_A0_ drives the level of anisotropy between parallel and perpendicular diffusion and {chi} modulates the magnitude of the diffusion coefficients, while in our choice of units, M is unimportant except in the sub-Alfvenic (M_A0_<~0.5) regime. Our finding that superdiffusion is ubiquitous potentially explains the apparent discrepancy between CR diffusion coefficients inferred from measurements close to individual sources compared to those measured on larger, Galactic scales. Finally, we present empirical fits for the diffusion coefficients as a function of plasma parameters that may be used as subgrid recipes for global ISM, galaxy, or cosmological simulations.2023MNRAS.519.1503Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/519/1503CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/519/1503https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/519/1503http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/519/1503https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/519/1503https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/519/1503http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/519/1503GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/MNRAS/519/1503/dataMeasured MHD plasma parameters and all the fitted cosmic ray transport data pointsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordinte_dperpC3[] Lower 16th quartile error/uncertainty for dperpC3stat.errordoubleE_aperpC1Upper 84th quartile error/uncertainty for aperpC1stat.error;stat.maxdoubleMachTurbulent Mach number of the FLASH simulationmeta.iddoubleE_MachUpper 84th quartile error/uncertainty for the measured turbulent mach numberstat.error;stat.maxdoublee_Mach[] Lower 16th quartile error/uncertainty for the measured turbulent mach numberstat.errordoubleMa0Mean field Alfven mach number of the FLASH simulationmeta.id;obs.fielddoubleE_Ma0Upper 84th quartile error/uncertainty for the mean field Alfven mach numberstat.error;stat.maxdoublee_Ma0[] Lower 16th quartile error/uncertainty for the mean field Alfven mach numberstat.errordoublekperpC0Fitted perpendicular diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 1 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kperpC0Upper 84th quartile error/uncertainty for kperpC0 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kperpC0[] Lower 16th quartile error/uncertainty for kperpC0 (in ^l^_{alpha}_.tau unit)stat.errordoublekperpC1Fitted perpendicular diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.1 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kperpC1Upper 84th quartile error/uncertainty for kperpC1 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kperpC1[] Lower 16th quartile error/uncertainty for kperpC1 (in ^l^_{alpha}_.tau unit)stat.errordoublekperpC2Fitted perpendicular diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.01 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kperpC2Upper 84th quartile error/uncertainty for kperpC2 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kperpC2[] Lower 16th quartile error/uncertainty for kperpC2 (in ^l^_{alpha}_.tau unit)stat.errordoublekperpC3Fitted perpendicular diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.001 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kperpC3Upper 84th quartile error/uncertainty for kperpC3 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kperpC3[] Lower 16th quartile error/uncertainty for kperpC3 (in ^l^_{alpha}_.tau unit)stat.errordoublekperpC4Fitted perpendicular diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.0001 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kperpC4Upper 84th quartile error/uncertainty for kperpC4 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kperpC4[] Lower 16th quartile error/uncertainty for kperpC4 (in ^l^_{alpha}_.tau unit)stat.errordoublekperpC5? Fitted perpendicular diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.00001 (in ^l^_{alpha}_.tau unit)meta.notedoublenullableE_kperpC5? Upper 84th quartile error/uncertainty for kperpC5 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublenullablee_kperpC5[]? Lower 16th quartile error/uncertainty for kperpC5 (in ^l^_{alpha}_.tau unit)stat.errordoublenullablekparC0Fitted parallel diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 1 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kparC0Upper 84th quartile error/uncertainty for kparC0 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kparC0Lower 84th quartile error/uncertainty for kparC0 (in ^l^_{alpha}_.tau unit)stat.errordoublekparC1Fitted parallel diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.1 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kparC1Upper 84th quartile error/uncertainty for kparC1 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kparC1[] Lower 16th quartile error/uncertainty for kparC1 (in ^l^_{alpha}_.tau unit)stat.errordoublekparC2Fitted parallel diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.01 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kparC2Upper 84th quartile error/uncertainty for kparC2 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kparC2[] Lower 16th quartile error/uncertainty for kparC2 (in ^l^_{alpha}_.tau unit)stat.errordoublekparC3Fitted parallel diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.001 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kparC3Upper 84th quartile error/uncertainty for kparC3 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kparC3[] Lower 16th quartile error/uncertainty for kparC3 (in ^l^_{alpha}_.tau unit)stat.errordoublekparC4Fitted parallel diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.0001 (in ^l^_{alpha}_.tau unit)meta.notedoubleE_kparC4Upper 84th quartile error/uncertainty for kparC4 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublee_kparC4[] Lower 16th quartile error/uncertainty for kparC4 (in ^l^_{alpha}_.tau unit)stat.errordoubleE_aparC5? Upper 84th quartile error/uncertainty for aparC5stat.error;stat.maxdoublenullablekparC5? Fitted parallel diffusion coefficient (kappa) for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.00001 (in ^l^_{alpha}_.tau unit)meta.notedoublenullableE_kparC5? Upper 84th quartile error/uncertainty for kparC5 (in ^l^_{alpha}_.tau unit)stat.error;stat.maxdoublenullablee_kparC5[]? Lower 16th quartile error/uncertainty for kparC5 (in ^l^_{alpha}_.tau unit)stat.errordoublenullabledperpC0Dimensionless drift parameter perpendicular to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 1 (1)stat.fit.paramdoubleE_dperpC0Upper 84th quartile error/uncertainty for dperpC0stat.error;stat.maxdoublee_dperpC0Lower 84th quartile error/uncertainty for dperpC0stat.errordoubledperpC1Dimensionless drift parameter perpendicular to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.1 (1)stat.fit.paramdoubleE_dperpC1Upper 84th quartile error/uncertainty for dperpC1stat.error;stat.maxdoublee_dperpC1[] Lower 16th quartile error/uncertainty for dperpC1stat.errordoubledperpC2Dimensionless drift parameter perpendicular to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.01 (1)stat.fit.paramdoubleE_dperpC2Upper 84th quartile error/uncertainty for dperpC2stat.error;stat.maxdoublee_dperpC2[] Lower 16th quartile error/uncertainty for dperpC2stat.errordoubledperpC3Dimensionless drift parameter perpendicular to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.001 (1)stat.fit.paramdoubleE_dperpC3Upper 84th quartile error/uncertainty for dperpC3stat.error;stat.maxdoubledperpC4Dimensionless drift parameter perpendicular to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.0001 (1)stat.fit.paramdoubleE_dperpC4Upper 84th quartile error/uncertainty for dperpC4stat.error;stat.maxdoublee_dperpC4[] Lower 16th quartile error/uncertainty for dperpC4stat.errordoubledperpC5? Dimensionless drift parameter perpendicular to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.00001 (1)stat.fit.paramdoublenullableE_dperpC5? Upper 84th quartile error/uncertainty for dperpC5stat.error;stat.maxdoublenullablee_dperpC5[]? Lower 16th quartile error/uncertainty for dperpC5stat.errordoublenullabledparC0Dimensionless drift parameter parallel to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 1 (1)stat.fit.paramdoubleE_dparC0Upper 84th quartile error/uncertainty for dparC0stat.error;stat.maxdoublee_dparC0Lower 84th quartile error/uncertainty for dparC0stat.errordoubledparC1Dimensionless drift parameter parallel to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.1 (1)stat.fit.paramdoubleE_dparC1Upper 84th quartile error/uncertainty for dparC1stat.error;stat.maxdoublee_dparC1[] Lower 16th quartile error/uncertainty for dparC1stat.errordoubledparC2Dimensionless drift parameter parallel to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.01 (1)stat.fit.paramdoubleE_dparC2Upper 84th quartile error/uncertainty for dparC2stat.error;stat.maxdoublee_dparC2[] Lower 16th quartile error/uncertainty for dparC2stat.errordoubledparC3Dimensionless drift parameter parallel to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.001 (1)stat.fit.paramdoubleE_dparC3Upper 84th quartile error/uncertainty for dparC3stat.error;stat.maxdoublee_dparC3[] Lower 16th quartile error/uncertainty for dparC3stat.errordoubledparC4Dimensionless drift parameter parallel to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.0001 (1)stat.fit.paramdoubleE_dparC4Upper 84th quartile error/uncertainty for dparC4stat.error;stat.maxdoublee_dparC4[] Lower 16th quartile error/uncertainty for dparC4stat.errordoubledparC5? drift parameter parallel to the mean B field for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.00001 (1)stat.fit.paramdoublenullableE_dparC5? Upper 84th quartile error/uncertainty for dparC5stat.error;stat.maxdoublenullablee_dparC5[]? Lower 16th quartile error/uncertainty for dparC5stat.errordoublenullableaperpC0Superdiffusion parameter alpha for perpendicular direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 1 (2)stat.fit.paramdoubleE_aperpC0Upper 84th quartile error/uncertainty for aperpC0stat.error;stat.maxdoublee_aperpC0[] Lower 16th quartile error/uncertainty for aperpC0stat.errordoubleaperpC1Superdiffusion parameter alpha for perpendicular direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.1 (2)stat.fit.paramdoublee_aperpC1[] Lower 16th quartile error/uncertainty for aperpC1stat.errordoubleaperpC2Superdiffusion parameter alpha for perpendicular direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.01 (2)stat.fit.paramdoubleE_aperpC2Upper 84th quartile error/uncertainty for aperpC2stat.error;stat.maxdoublee_aperpC2[] Lower 16th quartile error/uncertainty for aperpC2stat.errordoubleaperpC3Superdiffusion parameter alpha for perpendicular direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.001 (2)stat.fit.paramdoubleE_aperpC3Upper 84th quartile error/uncertainty for aperpC3stat.error;stat.maxdoublee_aperpC3[] Lower 16th quartile error/uncertainty for aperpC3stat.errordoubleaperpC4Superdiffusion parameter alpha for perpendicular direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.0001 (2)stat.fit.paramdoubleE_aperpC4Upper 84th quartile error/uncertainty for aperpC4stat.error;stat.maxdoublee_aperpC4[] Lower 16th quartile error/uncertainty for aperpC4stat.errordoubleaperpC5? Superdiffusion parameter alpha for perpendicular direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.00001 (2)stat.fit.paramdoublenullableE_aperpC5? Upper 84th quartile error/uncertainty for aperpC5stat.error;stat.maxdoublenullablee_aperpC5[]? Lower 16th quartile error/uncertainty for aperpC5stat.errordoublenullableaparC0Superdiffusion parameter alpha for parallel direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 1 (2)stat.fit.paramdoubleE_aparC0Upper 84th quartile error/uncertainty for aparC0stat.error;stat.maxdoublee_aparC0Lower 84th quartile error/uncertainty for aparC0stat.errordoubleaparC1Superdiffusion parameter alpha for parallel direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.1 (2)stat.fit.paramdoubleE_aparC1Upper 84th quartile error/uncertainty for aparC1stat.error;stat.maxdoublee_aparC1[] Lower 16th quartile error/uncertainty for aparC1stat.errordoubleaparC2Superdiffusion parameter alpha for parallel direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.01 (2)stat.fit.paramdoubleE_aparC2Upper 84th quartile error/uncertainty for aparC2stat.error;stat.maxdoublee_aparC2[] Lower 16th quartile error/uncertainty for aparC2stat.errordoubleaparC3Superdiffusion parameter alpha for parallel direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.001 (2)stat.fit.paramdoubleE_aparC3Upper 84th quartile error/uncertainty for aparC3stat.error;stat.maxdoublee_aparC3[] Lower 16th quartile error/uncertainty for aparC3stat.errordoubleaparC4Superdiffusion parameter alpha for parallel direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.0001 (2)stat.fit.paramdoubleE_aparC4Upper 84th quartile error/uncertainty for aparC4stat.error;stat.maxdoublee_aparC4[] Lower 16th quartile error/uncertainty for aparC4stat.errordoubleaparC5? Superdiffusion parameter alpha for parallel direction for the given Mach and Alfven mach numbers (aligned by row) with the ion fraction chi = 0.00001 (2)stat.fit.paramdoublenullablee_aparC5[]? Lower 16th quartile error/uncertainty for aparC5stat.errordoublenullable