Please use this identifier to cite or link to this item:
Full metadata record
DC FieldValueLanguage
dc.contributor.authorRodriguez-Rico, C.A.-
dc.contributor.authorGoss, W.M.-
dc.contributor.authorViallefond, F.-
dc.contributor.authorZhao, J.H.-
dc.contributor.authorGomez, Y.-
dc.contributor.authorAnantharamaiah, K.R.-
dc.identifier.citationAstrophysical Journal, 2005, Vol.633, p198-204en
dc.identifier.issn1538-4357 (online)-
dc.descriptionRestricted Access. An open-access version is available at (one of the alternative locations)en
dc.description.abstractWe present high angular resolution (0.7") observations made with the Very Large Array (VLA) of the radio recombination line (RRL) H53α and radio continuum emission at 43 GHz from the ultraluminous infrared galaxy (ULIRG) Arp 220. The 43 GHz continuum emission shows a compact structure (~2") with two peaks separated by ~1", the east (E) and west (W) components, that correspond to each galactic nucleus of the merger. The spectral indices for both the E and W components, using radio continuum images at 8.3 and 43 GHz are typical of synchrotron emission (α~-1.0). Our 43 GHz continuum and H53α line observations confirm the flux densities predicted by the models proposed by Anantharamaiah et al. (2000). This agreement with the models implies the presence of high-density (~105 cm-3) compact H II regions (~0.1 pc) in Arp 220. The integrated H53α line emission is stronger toward the nonthermal radio continuum peaks, which are also coincident with the peaks of molecular emission of the H2CO. The coincidence between the integrated H53α and the H2CO maser line emission suggests that the recent star-forming regions, traced by the high-density gas, are located mainly in regions that are close to the two radio continuum peaks. A velocity gradient of ~0.30 km s-1 pc-1 in the H53α RRL is observed toward the E component, and a second velocity gradient of ~0.15 km s-1 pc-1 is detected toward the W component. The orientations of these velocity gradients are in agreement with previous CO, H I, and OH observations. The kinematics of the high-density ionized gas traced by the H53α line are consistent with two counterrotating disks as suggested by the CO and H I observations.en
dc.format.extent475547 bytes-
dc.publisherThe University of Chicago Press for the American Astronomical Societyen
dc.rights2005 American Astronomical Societyen
dc.subjectGalaxies: Generalen
dc.subjectGalaxies: Individual: Name: Arp 220en
dc.subjectGalaxies: Starbursten
dc.subjectRadio Continuum: Galaxiesen
dc.subjectRadio Lines: Galaxiesen
dc.titleVLA H53α radio recombination line observations of the ultraluminous infrared galaxy Arp 220en
dc.additionalErratum published in Astrophysical Journal, 2007, V668, p625-
Appears in Collections:Research Papers (A&A)

Files in This Item:
File Description SizeFormat 
2005 ApJ V633 p198-204.pdf
  Restricted Access
Restricted Access464.4 kBAdobe PDFView/Open Request a copy
2005 ApJ V633 p198E.pdf
  Restricted Access
Erratum29.1 kBAdobe PDFView/Open Request a copy

Items in RRI Digital Repository are protected by copyright, with all rights reserved, unless otherwise indicated.