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J/ApJ/831/18  H through Ni intensities in LISM from Voyager 1  (Cummings+, 2016)

Galactic cosmic rays in the local interstellar medium: Voyager 1 observations and model results. Cummings A.C., Stone E.C., Heikkila B.C., Lal N., Webber W.R., Johannesson G., Moskalenko I.V., Orlando E., Porter T.A. <Astrophys. J., 831, 18-18 (2016)> =2016ApJ...831...18C (SIMBAD/NED BibCode)
ADC_Keywords: Interstellar medium ; Abundances ; Models Mission_Name: Voyager1 Keywords: cosmic rays; ISM: abundances; ISM: clouds Abstract: Since 2012 August Voyager 1 has been observing the local interstellar energy spectra of Galactic cosmic-ray nuclei down to 3MeV/nuc and electrons down to 2.7MeV. The H and He spectra have the same energy dependence between 3 and 346MeV/nuc, with a broad maximum in the 10-50MeV/nuc range and a H/He ratio of 12.2±0.9. The peak H intensity is ∼15 times that observed at 1AU, and the observed local interstellar gradient of 3-346MeV H is -0.009±0.055%/AU, consistent with models having no local interstellar gradient. The energy spectrum of electrons (e-+e+) with 2.7-74MeV is consistent with E-1.30±0.05 and exceeds the H intensity at energies below ∼50MeV. Propagation model fits to the observed spectra indicate that the energy density of cosmic-ray nuclei with >3MeV/nuc and electrons with >3MeV is 0.83-1.02eV/cm3 and the ionization rate of atomic H is in the range of 1.51-1.64x10-17s-1. This rate is a factor >10 lower than the ionization rate in diffuse interstellar clouds, suggesting significant spatial inhomogeneity in low-energy cosmic rays or the presence of a suprathermal tail on the energy spectrum at much lower energies. The propagation model fits also provide improved estimates of the elemental abundances in the source of Galactic cosmic rays. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table13.dat 381 109 *GALPROP model DR intensities in local interstellar medium (LISM) for H through Ni table14.dat 381 109 *GALPROP model PD1 intensities in local interstellar medium (LISM) for H through Ni table15.dat 381 109 *GALPROP model PD2 intensities in local interstellar medium (LISM) for H through Ni table16.dat 268 38 Leaky-box model (LBM) intensities in local interstellar medium (LISM) for H through Ni, except for Li and Ca, which are not calculated
Note on table13.dat, table14.dat and table15.dat: We explore two basic types of propagation models that are widely used to reproduce Galactic cosmic-ray (GCR) data: the diffusive-reacceleration (DR) model and the plain diffusion (PD) model. In case of the PD model, we use one break (PD1 model, ρq,2=infinity) and two breaks (PD2 model). See appendix B for further explanations.
See also: J/ApJ/764/L19 : Methanol emission from the Galactic Center (Yusef-Zadeh+, 2013) J/A+A/534/A54 : GALPROP programme (Strong+, 2011) Byte-by-byte Description of file: table1[345].dat
Bytes Format Units Label Explanations
1- 17 F17.6 --- E [3/1.07e+09] Energy in units of MeV/nuc 19- 30 E12.6 --- H Hydrogen intensity (1) 32- 43 E12.6 --- He Helium intensity (1) 45- 56 E12.6 --- Li Lithum intensity (1) 58- 69 E12.6 --- Be Beryllium intensity (1) 71- 82 E12.6 --- B Boron intensity (1) 84- 95 E12.6 --- C Carbon intensity (1) 97-108 E12.6 --- N Nitrogen intensity (1) 110-121 E12.6 --- O Oxygen intensity (1) 123-134 E12.6 --- F Fluorine intensity (1) 136-147 E12.6 --- Ne Neon intensity (1) 149-160 E12.6 --- Na Sodium intensity (1) 162-173 E12.6 --- Mg Magnesium intensity (1) 175-186 E12.6 --- Al Aluminium intensity (1) 188-199 E12.6 --- Si Silicon intensity (1) 201-212 E12.6 --- P Phosphorus intensity (1) 214-225 E12.6 --- S Sulfur intensity (1) 227-238 E12.6 --- Cl Chlorine intensity (1) 240-251 E12.6 --- Ar Argon intensity (1) 253-264 E12.6 --- K Potassium intensity (1) 266-277 E12.6 --- Ca Calcium intensity (1) 279-290 E12.6 --- Sc Scandium intensity (1) 292-303 E12.6 --- Ti Titanium intensity (1) 305-316 E12.6 --- V Vanadium intensity (1) 318-329 E12.6 --- Cr Chromium intensity (1) 331-342 E12.6 --- Mn Manganese intensity (1) 344-355 E12.6 --- Fe Iron intensity (1) 357-368 E12.6 --- Co Cobalt intensity (1) 370-381 E12.6 --- Ni Nickel intensity (1)
Note (1): In units of (m2.s.sr.MeV/nuc)-1.
Byte-by-byte Description of file: table16.dat
Bytes Format Units Label Explanations
1- 8 F8.1 --- E [3/134943] Energy in units of MeV/nuc 10- 18 E9.3 --- H Hydrogen intensity (1) 20- 28 E9.3 --- He Helium intensity (1) 30- 38 E9.3 --- Be Beryllium intensity (1) 40- 48 E9.3 --- B Boron intensity (1) 50- 58 E9.3 --- C Carbon intensity (1) 60- 68 E9.3 --- N Nitrogen intensity (1) 70- 78 E9.3 --- O Oxygen intensity (1) 80- 88 E9.3 --- F Fluorine intensity (1) 90- 98 E9.3 --- Ne Neon intensity (1) 100-108 E9.3 --- Na Sodium intensity (1) 110-118 E9.3 --- Mg Magnesium intensity (1) 120-128 E9.3 --- Al Aluminium intensity (1) 130-138 E9.3 --- Si Silicon intensity (1) 140-148 E9.3 --- P Phosphorus intensity (1) 150-158 E9.3 --- S Sulfur intensity (1) 160-168 E9.3 --- Cl Chlorine intensity (1) 170-178 E9.3 --- Ar Argon intensity (1) 180-188 E9.3 --- K Potassium intensity (1) 190-198 E9.3 --- Sc Scandium intensity (1) 200-208 E9.3 --- Ti Titanium intensity (1) 210-218 E9.3 --- V Vanadium intensity (1) 220-228 E9.3 --- Cr Chromium intensity (1) 230-238 E9.3 --- Mn Manganese intensity (1) 240-248 E9.3 --- Fe Iron intensity (1) 250-258 E9.3 --- Co Cobalt intensity (1) 260-268 E9.3 --- Ni Nickel intensity (1)
Note (1): Local interstellar medium (LISM) spectra from Leaky Box model with P0=1.0. In units of (m2.s.sr.MeV/nuc)-1.
History: From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 25-Jan-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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