View in EDS

On the minimum of line width of the backscattered solar Ly-[formula omitted] profile measured by SOHO/SWAN.

Saved in:
Bibliographic Details
Title: On the minimum of line width of the backscattered solar Ly-[formula omitted] profile measured by SOHO/SWAN.
Authors: Titova, Anastasia1,2 (AUTHOR) avtitova@cosmos.ru, Izmodenov, Vladislav1,2,3 (AUTHOR), Korolkov, Sergey1 (AUTHOR)
Source: Advances in Space Research. Jul2026, Vol. 78 Issue 2, p1702-1710. 9p.
Subjects: Velocity distribution (Statistical mechanics), Interstellar medium, Kinetic theory of gases, Solar wind, Heliosphere, Frequency spectra
Abstract: Solar Ly- α photons are scattered by interstellar hydrogen (H) atoms that penetrate into the heliosphere through the region of the solar wind interaction with the local interstellar medium. The spectra of scattered Ly- α reflect the properties of the velocity distribution of the interstellar H atoms. The spectra of backscattered Ly- α have been reconstructed in anti-sunward directions by Quemerais et al. (Quémerais et al. (1999, 2006a)). One of the spectacular results of this reconstruction was the discovery of the minimum of the width of the backscattered spectra in the direction (nearly) perpendicular to the interstellar flow direction. Originally, the minimum was interpreted as a proof of the secondary interstellar atom presence inside the heliosphere. However, later Katushkina and Izmodenov (2011) , using a two-population kinetic model of the interstellar H atoms in the heliosphere, demonstrated that the minimum cannot be produced in their quite complete model. In this paper, we performed numerical calculations of solar backscattered Ly- α spectra with the same model as in Katushkina and Izmodenov (2011). A key novel aspect of the presented analyses is the procedure of the obtaining the width values. Specifically, we obtain the widths following the same approach as in the analysis of SOHO/SWAN data: the numerically computed spectra are truncated at velocities of ± 30 km/s and subsequently fitted with symmetric Gaussian functions. Our results show that the minimum arises as a direct consequence of applying this procedure to spectra generated by a two-population model. When the same analysis is performed on a single-population model, no such minimum appears. Thus, the longstanding issue of providing a theoretical explanation for the observed minimum is resolved. [ABSTRACT FROM AUTHOR]
Copyright of Advances in Space Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
FullText Text:
  Availability: 0
Header DbId: egs
DbLabel: Engineering Source
An: 194701142
AccessLevel: 6
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 0
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: On the minimum of line width of the backscattered solar Ly-[formula omitted] profile measured by SOHO/SWAN.
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Titova%2C+Anastasia%22">Titova, Anastasia</searchLink><relatesTo>1,2</relatesTo> (AUTHOR)<i> avtitova@cosmos.ru</i><br /><searchLink fieldCode="AR" term="%22Izmodenov%2C+Vladislav%22">Izmodenov, Vladislav</searchLink><relatesTo>1,2,3</relatesTo> (AUTHOR)<br /><searchLink fieldCode="AR" term="%22Korolkov%2C+Sergey%22">Korolkov, Sergey</searchLink><relatesTo>1</relatesTo> (AUTHOR)
– Name: TitleSource
  Label: Source
  Group: Src
  Data: <searchLink fieldCode="JN" term="%22Advances+in+Space+Research%22">Advances in Space Research</searchLink>. Jul2026, Vol. 78 Issue 2, p1702-1710. 9p.
– Name: Subject
  Label: Subjects
  Group: Su
  Data: <searchLink fieldCode="DE" term="%22Velocity+distribution+%28Statistical+mechanics%29%22">Velocity distribution (Statistical mechanics)</searchLink><br /><searchLink fieldCode="DE" term="%22Interstellar+medium%22">Interstellar medium</searchLink><br /><searchLink fieldCode="DE" term="%22Kinetic+theory+of+gases%22">Kinetic theory of gases</searchLink><br /><searchLink fieldCode="DE" term="%22Solar+wind%22">Solar wind</searchLink><br /><searchLink fieldCode="DE" term="%22Heliosphere%22">Heliosphere</searchLink><br /><searchLink fieldCode="DE" term="%22Frequency+spectra%22">Frequency spectra</searchLink>
– Name: Abstract
  Label: Abstract
  Group: Ab
  Data: Solar Ly- α photons are scattered by interstellar hydrogen (H) atoms that penetrate into the heliosphere through the region of the solar wind interaction with the local interstellar medium. The spectra of scattered Ly- α reflect the properties of the velocity distribution of the interstellar H atoms. The spectra of backscattered Ly- α have been reconstructed in anti-sunward directions by Quemerais et al. (Quémerais et al. (1999, 2006a)). One of the spectacular results of this reconstruction was the discovery of the minimum of the width of the backscattered spectra in the direction (nearly) perpendicular to the interstellar flow direction. Originally, the minimum was interpreted as a proof of the secondary interstellar atom presence inside the heliosphere. However, later Katushkina and Izmodenov (2011) , using a two-population kinetic model of the interstellar H atoms in the heliosphere, demonstrated that the minimum cannot be produced in their quite complete model. In this paper, we performed numerical calculations of solar backscattered Ly- α spectra with the same model as in Katushkina and Izmodenov (2011). A key novel aspect of the presented analyses is the procedure of the obtaining the width values. Specifically, we obtain the widths following the same approach as in the analysis of SOHO/SWAN data: the numerically computed spectra are truncated at velocities of ± 30 km/s and subsequently fitted with symmetric Gaussian functions. Our results show that the minimum arises as a direct consequence of applying this procedure to spectra generated by a two-population model. When the same analysis is performed on a single-population model, no such minimum appears. Thus, the longstanding issue of providing a theoretical explanation for the observed minimum is resolved. [ABSTRACT FROM AUTHOR]
– Name: AbstractSuppliedCopyright
  Label:
  Group: Ab
  Data: <i>Copyright of Advances in Space Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.</i> (Copyright applies to all Abstracts.)
PLink https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&db=egs&AN=194701142
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.1016/j.asr.2026.04.063
    Languages:
      – Code: eng
        Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 9
        StartPage: 1702
    Subjects:
      – SubjectFull: Velocity distribution (Statistical mechanics)
        Type: general
      – SubjectFull: Interstellar medium
        Type: general
      – SubjectFull: Kinetic theory of gases
        Type: general
      – SubjectFull: Solar wind
        Type: general
      – SubjectFull: Heliosphere
        Type: general
      – SubjectFull: Frequency spectra
        Type: general
    Titles:
      – TitleFull: On the minimum of line width of the backscattered solar Ly-[formula omitted] profile measured by SOHO/SWAN.
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Titova, Anastasia
      – PersonEntity:
          Name:
            NameFull: Izmodenov, Vladislav
      – PersonEntity:
          Name:
            NameFull: Korolkov, Sergey
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 15
              M: 07
              Text: Jul2026
              Type: published
              Y: 2026
          Identifiers:
            – Type: issn-print
              Value: 02731177
          Numbering:
            – Type: volume
              Value: 78
            – Type: issue
              Value: 2
          Titles:
            – TitleFull: Advances in Space Research
              Type: main
ResultId 1