Study On The Radio Properties Of The OH Supermaser Galaxy IIZw 09

There are some extremely bright galaxies in the Universe（the luminosity is dominated by the emission of H₂O and OH megamaser）,because their extreme luminosity has led scientists to crush on such galaxies and to investigate the mechanisms behind them.Since Astronomical masers phenomena occur mainly in the interiors of merging galaxies and their properties,ori-gin and the physical environment they reveal that are remain largely unknown.However the large physical size of OH megamaser（OHM）galaxies suggests that they have a fundamentally different origin from the Galactic OHM and The origin of the OHM was thus used as a probe,enabling a good quantification of the relationship between mega-maser emission and the host galaxies environment.IIZw 096 is a rare example of a neighboring galaxy with extremely bright luminosity,complex morphological structure,and is a multi-system merging galaxy in the phase of evolution.Because of the possible presence of compact active galactic nuclei（AGN）in merging galaxies,previous models of OHMs that predict extreme star formation as their sole driving mechanism may be incomplete.Some previously classified galaxies found to have OHMs are now optically observed as AGNs,and we have found through our literature that the galaxies are optically classified as starburst galaxies,but there is a lot of evidence for a hidden active galactic nucleus.So The main goal of this paper is to further investigate the properties of the high-resolution structure of the OH megamaser and to identify possible links to environmental conditions,including the presence of dense gas,compact radio continuum emission,and the possible stage of merger evolution.First,based on the two epochs European Very Long Baseline Interferometry（VLBI）Network（EVN）archive data from OH observations of IIZw 096,we confirm that the high-resolution OH emission in this source mainly comes from two spots（OH1 and OH2）of comp D1 of this merging system.What’s more by using archival data from the Very Long Baseline Array（VLBA）,Very Large Array（VLA）,and Atacama Large Millimeter/sub-millimeter Ar-ray（ALMA）observations,we investigated the properties of the environment of this component through HI,CO（3-2）,and HCO+（4-3）lines and the multi-band radio continuum emission.We find that the environment around D1 shows the brightest CO,HCO+emission lines and no clear velocity structure associated with circular motions,making it different from most other OHMs in the literature,which might have been caused by an effect during the merger stage.Meanwhile,we found that the CO emission shows three velocity structures around D1,includ-ing the central broad FWHM region,the double peak region where the CO line profile shows two separated peaks,and the region of the high-velocity clouds where the CO line peaks,at a high velocity(～11000 km s^-1).Similarly,HI observations in absorption also show high ve-locity clouds around the D1 region,which might be due to inflows caused by the merging of two or more galaxy components.Last but not least based on the high-resolution K-band VLA and L-band VLBA observations of the radio continuum emission,we derived the brightness temperature in the range 10⁵K to 10⁶K,which is consistent with other starburst dominant OHM sources in the literature.The multi-band VLA observations show that,in addition to synchrotron emission,the D component of the radio continuum emission may also have a free emission contribution.Thus,these results support the OH megamaser is originated starburst by radio studies,in other words,there is no the presence of AGN in IIZw 096.