In this comment on the article“Locating the source field lines of Jovian decametric radio emissions”by Wang YM et al.,2020,we discuss the assumptions used by the authors to compute the beaming angle of Jupiter’s de...In this comment on the article“Locating the source field lines of Jovian decametric radio emissions”by Wang YM et al.,2020,we discuss the assumptions used by the authors to compute the beaming angle of Jupiter’s decametric emissions induced by the moon Io.Their method,relying on multi-point radio observations,was applied to a single event observed on 14th March 2014 by Wind and both STEREO A/B spacecraft from~5 to~16 MHz.They have erroneously identified the emission as a northern(Io-B type)instead of a southern one(Io-D type).We encourage the authors to update their results with the correct hemisphere of origin and to test their method on a larger sample of Jupiter-Io emissions.展开更多
Annual variations of interstellar scintillation can be modelled to constrain parameters of the ionized interstellar medium.If a pulsar is in a binary system,then investigating the orbital parameters is possible throug...Annual variations of interstellar scintillation can be modelled to constrain parameters of the ionized interstellar medium.If a pulsar is in a binary system,then investigating the orbital parameters is possible through analysis of the orbital variation of scintillation.In observations carried out from 2011 to 2020 by the European Pulsar Timing Array radio telescopes,PSRs J0613-0200and J0636+5128 show strong annual variations in their scintillation velocity,while the former additionally exhibits an orbital fluctuation.Bayesian theory and Markov-chain-Monte-Carlo methods are used to interpret these periodic variations.We assume a thin and anisotropic scattering screen model,and discuss the mildly and extremely anisotropic scattering cases.PSR J0613-0200is best described by mildly anisotropic scattering,while PSR J0636+5128 exhibits extremely anisotropic scattering.We measure the distance,velocity,and degree of anisotropy of the scattering screen for our two pulsars,finding that scattering screen distances from Earth for PSRs J0613-0200 and J0636+5128 are 316_(-20)^(+28)pc and 262_(-38)^(+96)pc,respectively.The positions of these scattering screens are coincident with the shell of the Local Bubble towards both pulsars.These associations add to the growing evidence of the Local Bubble shell as a dominant region of scattering along many sightlines.展开更多
基金supported by the Paris Astronomical Data Centre(PADC)at Observatoire de Paris.
文摘In this comment on the article“Locating the source field lines of Jovian decametric radio emissions”by Wang YM et al.,2020,we discuss the assumptions used by the authors to compute the beaming angle of Jupiter’s decametric emissions induced by the moon Io.Their method,relying on multi-point radio observations,was applied to a single event observed on 14th March 2014 by Wind and both STEREO A/B spacecraft from~5 to~16 MHz.They have erroneously identified the emission as a northern(Io-B type)instead of a southern one(Io-D type).We encourage the authors to update their results with the correct hemisphere of origin and to test their method on a larger sample of Jupiter-Io emissions.
基金supported by the National Natural Science Foundation of China(Grant No.12003047)the Major Science and Technology Program of Xinjiang Uygur Autonomous Region(Grant No.2022A03013-2)+2 种基金the Natural Science Foundation of Xinjiang Uygur Autonomous Region(Grant No.2022D01D85)support by the Deutsche Forschungsgemeinschaft(DFG)through the Heisenberg programme(Project No.433075039)financial support from“Programme National de Cosmologie et Galaxies”(PNCG)of CNRS/INSU,France。
文摘Annual variations of interstellar scintillation can be modelled to constrain parameters of the ionized interstellar medium.If a pulsar is in a binary system,then investigating the orbital parameters is possible through analysis of the orbital variation of scintillation.In observations carried out from 2011 to 2020 by the European Pulsar Timing Array radio telescopes,PSRs J0613-0200and J0636+5128 show strong annual variations in their scintillation velocity,while the former additionally exhibits an orbital fluctuation.Bayesian theory and Markov-chain-Monte-Carlo methods are used to interpret these periodic variations.We assume a thin and anisotropic scattering screen model,and discuss the mildly and extremely anisotropic scattering cases.PSR J0613-0200is best described by mildly anisotropic scattering,while PSR J0636+5128 exhibits extremely anisotropic scattering.We measure the distance,velocity,and degree of anisotropy of the scattering screen for our two pulsars,finding that scattering screen distances from Earth for PSRs J0613-0200 and J0636+5128 are 316_(-20)^(+28)pc and 262_(-38)^(+96)pc,respectively.The positions of these scattering screens are coincident with the shell of the Local Bubble towards both pulsars.These associations add to the growing evidence of the Local Bubble shell as a dominant region of scattering along many sightlines.
