Hot Plasma in the Magnetotail Lobes Shows Characteristics Consistent With Closed Field Lines Trapped in the Lobes
Hot Plasma in the Magnetotail Lobes Shows Characteristics Consistent With Closed Field Lines Trapped in the Lobes
 
  We examine the magnetotail using data from the Hot Ion Analyzer on Cluster 1 during 2001–2009. We develop and utilize an algorithm in order to identify times during which Cluster 1 is in the magnetotail lobe but observes plasma, which is hotter than our expectations of the lobe. We analyze the prevailing Interplanetary Magnetic Field (IMF) (Formula presented.) conditions for our algorithm and a reference algorithm (with no particle energy criteria) and find that the periods we select are, on average, (Formula presented.) nT more toward northward IMF. Examining the temperature in the magnetotail for our periods shows that the morphology of the average temperature is consistent with the Milan et al. (2005, https://doi.org/10.1029/2004JA010835) model of a magnetotail structure during northward IMF, in which closed field lines are prevented from convecting to the dayside, causing them and the plasma trapped on them to protrude into the magnetotail lobes. We also find evidence that (Formula presented.) of our identified periods may be driven by direct entry into the magnetosphere from the solar wind.
IMF BY, hot plasma, magnetotail, northward IMF, theta aurora, transpolar arcs
  
  
  
    
      Coxon, John C.
      
        566baea5-6a30-4855-bde3-a09c115efde4
      
     
  
    
      Fear, Robert C.
      
        8755b9ed-c7dc-4cbb-ac9b-56235a0431ab
      
     
  
    
      Reidy, Jade A.
      
        7dbc1f34-be44-4269-a3f4-9f490aaaadc7
      
     
  
    
      Fryer, Laura Jane
      
        6a9fd678-d71b-4352-a74f-51fa0bdc4542
      
     
  
    
      Plank, James
      
        f3b87a76-4828-4a4a-bf38-c234a938eaac
      
     
  
  
   
  
  
    
    
  
    
    
  
    
      9 September 2021
    
    
  
  
    
      Coxon, John C.
      
        566baea5-6a30-4855-bde3-a09c115efde4
      
     
  
    
      Fear, Robert C.
      
        8755b9ed-c7dc-4cbb-ac9b-56235a0431ab
      
     
  
    
      Reidy, Jade A.
      
        7dbc1f34-be44-4269-a3f4-9f490aaaadc7
      
     
  
    
      Fryer, Laura Jane
      
        6a9fd678-d71b-4352-a74f-51fa0bdc4542
      
     
  
    
      Plank, James
      
        f3b87a76-4828-4a4a-bf38-c234a938eaac
      
     
  
       
    
 
  
    
      
  
  
  
  
  
  
    Coxon, John C., Fear, Robert C., Reidy, Jade A., Fryer, Laura Jane and Plank, James
  
  
  
  
   
    (2021)
  
  
    
    Hot Plasma in the Magnetotail Lobes Shows Characteristics Consistent With Closed Field Lines Trapped in the Lobes.
  
  
  
  
    Journal of Geophysical Research: Space Physics, 126 (9), [e2021JA029516].
  
   (doi:10.1029/2021JA029516). 
  
  
   
  
  
  
  
  
   
  
    
    
      
        
          Abstract
          We examine the magnetotail using data from the Hot Ion Analyzer on Cluster 1 during 2001–2009. We develop and utilize an algorithm in order to identify times during which Cluster 1 is in the magnetotail lobe but observes plasma, which is hotter than our expectations of the lobe. We analyze the prevailing Interplanetary Magnetic Field (IMF) (Formula presented.) conditions for our algorithm and a reference algorithm (with no particle energy criteria) and find that the periods we select are, on average, (Formula presented.) nT more toward northward IMF. Examining the temperature in the magnetotail for our periods shows that the morphology of the average temperature is consistent with the Milan et al. (2005, https://doi.org/10.1029/2004JA010835) model of a magnetotail structure during northward IMF, in which closed field lines are prevented from convecting to the dayside, causing them and the plasma trapped on them to protrude into the magnetotail lobes. We also find evidence that (Formula presented.) of our identified periods may be driven by direct entry into the magnetosphere from the solar wind.
         
      
      
        
          
            
  
    Text
 2021JA029516
     - Accepted Manuscript
   
  
    
      Restricted to Repository staff only
    
  
  
 
          
            
              Request a copy
            
           
            
           
        
          
            
  
    Text
 JGR Space Physics - 2021 - Coxon - Hot Plasma in the Magnetotail Lobes Shows Characteristics Consistent With Closed Field
     - Version of Record
   
  
  
    
  
 
          
            
          
            
           
            
           
        
        
       
    
   
  
  
  More information
  
    
      Accepted/In Press date: 19 July 2021
 
    
      e-pub ahead of print date: 9 August 2021
 
    
      Published date: 9 September 2021
 
    
  
  
    
  
    
  
    
  
    
  
    
  
    
     
        Keywords:
        IMF BY, hot plasma, magnetotail, northward IMF, theta aurora, transpolar arcs
      
    
  
    
  
    
  
  
        Identifiers
        Local EPrints ID: 453625
        URI: http://eprints.soton.ac.uk/id/eprint/453625
        
          
        
        
        
          ISSN: 2169-9380
        
        
          PURE UUID: 9471fbed-573a-43c1-9088-024a99b6721f
        
  
    
        
          
            
              
            
          
        
    
        
          
            
              
            
          
        
    
        
          
            
          
        
    
        
          
            
              
            
          
        
    
        
          
            
          
        
    
  
  Catalogue record
  Date deposited: 20 Jan 2022 17:39
  Last modified: 17 Mar 2024 03:34
  Export record
  
  
   Altmetrics
   
   
  
 
 
  
    
    
      Contributors
      
        
      
        
      
          
          Author:
          
            
              
              
                Jade A. Reidy
              
              
            
            
          
        
      
        
      
          
          Author:
          
            
              
              
                James Plank
              
              
            
            
          
        
      
      
      
    
  
   
  
    Download statistics
    
      Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
      
      View more statistics