Ultrafast outflows in ultraluminous X-ray sources
Ultrafast outflows in ultraluminous X-ray sources
 
  Ultraluminous X-ray sources (ULXs) are bright extragalactic sources with X-ray luminosities above 1039 erg s−1 powered by accretion onto compact objects. According to the first studies performed with XMM-Newton, ULXs seemed to be excellent candidates to host intermediate-mass black holes (102 − 4M⊙). However, in the last years, the interpretation of super-Eddington accretion onto stellar-mass black holes or neutron stars for most ULXs has gained a strong consensus. One critical missing piece to confirm the super-Eddington scenario was the direct detection of the massive, radiatively driven winds expected as atomic emission/absorption lines in the ULX spectra. The first evidence for winds was found as residuals in the soft X-ray spectra of ULXs. Very recently, we have been able to resolve these residuals into rest-frame emission and blueshifted (∼ 0.2c) absorption lines arising from highly ionized gas in the deep, high-resolution XMM-Newton spectra of two ULXs. The compact object is therefore surrounded by powerful ultrafast winds as predicted by models of hyper-Eddington accretion. Here we discuss the relevance of these discoveries and the importance of further deep XMM-Newton observations of powerful winds in many other ULXs to estimate the energetics of the wind, the geometry of the system, and the masses of the central accretors.
  
  
  234-240
  
    
      Pinto, C.
      
        9d6e45cf-4900-42c4-8ca0-134c0af99af2
      
     
  
    
      Fabian, A.
      
        0c353376-f159-4129-b03e-d3993c0c5406
      
     
  
    
      Middleton, M.
      
        f91b89d9-fd2e-42ec-aa99-1249f08a52ad
      
     
  
    
      Walton, D.
      
        a1a36b18-a77b-48e8-8665-45bbef0c7bd1
      
     
  
  
   
  
  
    
    
  
    
    
  
  
    
      Pinto, C.
      
        9d6e45cf-4900-42c4-8ca0-134c0af99af2
      
     
  
    
      Fabian, A.
      
        0c353376-f159-4129-b03e-d3993c0c5406
      
     
  
    
      Middleton, M.
      
        f91b89d9-fd2e-42ec-aa99-1249f08a52ad
      
     
  
    
      Walton, D.
      
        a1a36b18-a77b-48e8-8665-45bbef0c7bd1
      
     
  
       
    
 
  
    
      
  
  
  
  
  
  
    Pinto, C., Fabian, A., Middleton, M. and Walton, D.
  
  
  
  
   
    (2017)
  
  
    
    Ultrafast outflows in ultraluminous X-ray sources.
  
  
  
  
    Astronomische Nachrichten, 338 (2-3), .
  
   (doi:10.1002/asna.201713336). 
  
  
   
  
  
  
  
  
   
  
    
    
      
        
          Abstract
          Ultraluminous X-ray sources (ULXs) are bright extragalactic sources with X-ray luminosities above 1039 erg s−1 powered by accretion onto compact objects. According to the first studies performed with XMM-Newton, ULXs seemed to be excellent candidates to host intermediate-mass black holes (102 − 4M⊙). However, in the last years, the interpretation of super-Eddington accretion onto stellar-mass black holes or neutron stars for most ULXs has gained a strong consensus. One critical missing piece to confirm the super-Eddington scenario was the direct detection of the massive, radiatively driven winds expected as atomic emission/absorption lines in the ULX spectra. The first evidence for winds was found as residuals in the soft X-ray spectra of ULXs. Very recently, we have been able to resolve these residuals into rest-frame emission and blueshifted (∼ 0.2c) absorption lines arising from highly ionized gas in the deep, high-resolution XMM-Newton spectra of two ULXs. The compact object is therefore surrounded by powerful ultrafast winds as predicted by models of hyper-Eddington accretion. Here we discuss the relevance of these discoveries and the importance of further deep XMM-Newton observations of powerful winds in many other ULXs to estimate the energetics of the wind, the geometry of the system, and the masses of the central accretors.
         
      
      
        
          
            
  
    Text
 Ultrafast outflows in ultraluminous X-ray sources
     - Accepted Manuscript
   
  
  
    
  
 
          
            
          
            
           
            
           
        
        
       
    
   
  
  
  More information
  
    
      Accepted/In Press date: 2 November 2016
 
    
      e-pub ahead of print date: 29 March 2017
 
    
  
  
    
  
    
     
        Additional Information:
        Arxiv ref 1611.00623 Author confirms AM
      
    
  
    
     
        Venue - Dates:
        XXM-Newton: The Next Decade, , Madrid, Spain, 2016-05-09 - 2016-05-11
      
    
  
    
  
    
  
    
  
    
     
        Organisations:
        Astronomy Group
      
    
  
    
  
  
  
    
  
  
        Identifiers
        Local EPrints ID: 412017
        URI: http://eprints.soton.ac.uk/id/eprint/412017
        
          
        
        
        
          ISSN: 0004-6337
        
        
          PURE UUID: 6a929446-d98f-4c98-a533-c686ec741d1f
        
  
    
        
          
        
    
        
          
        
    
        
          
            
          
        
    
        
          
        
    
  
  Catalogue record
  Date deposited: 05 Jul 2017 16:31
  Last modified: 16 Mar 2024 05:30
  Export record
  
  
   Altmetrics
   
   
  
 
 
  
    
    
      Contributors
      
          
          Author:
          
            
            
              C. Pinto
            
          
        
      
          
          Author:
          
            
            
              A. Fabian
            
          
        
      
        
      
          
          Author:
          
            
            
              D. Walton
            
          
        
      
      
      
    
  
   
  
    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