3 L ∗ )which are highly-inclined, while, NGC 4501 is a moderately-inclined massive spiral ( ∼ 2 L ∗ ). It should be noted that NGC 4330, NGC 4402 and NGC 4522 are small spirals ( ∼ 0. All four spirals are approximately 1.5–3.3 degrees ( ∼ 0.4–0.9 Mpc) from the cluster center where many galaxies exhibit evidence for ongoing ram pressure stripping. Hence, all four of these galaxies have clear indications of strong ongoing ram pressure. (2009) that measured the radio deficit regions. NGC 4501 has a strong polarized ridge but is not in the same sample of Murphy et al. NGC 4330 has a strong radio deficit region but no prominent polarized ridge, perhaps because of an unfavorable viewing geometry (Vollmer & Leroy 2011). NGC lists 4522 the each properties have strong of our polarized sample ridges galaxies. ram disk pressure-induced of NGC the galaxy. galaxies in gas measures tails where resulting of the the from densities current ram strength of pressure cosmic of stripping) ram ray electrons pressure, are and since more magnetic this easily is likely identified fields to are be and related lower distinguished than to the in strength undisturbed from the of any main galaxies. found extraplanar in We ram are pressure most features interested affected (e.g. favors the polarized so highly-inclined partly ridges, reflect galaxies the local stripping radio because deficit history in regions such of the galaxies, are galaxies. pressure Our appears sample Beyond diminishes, unaffected. spiral optical 2004, ( after ∼ stellar 2007, 2 ram L ∗ ). side interactions and These lop-sided properties (Vollmer while massive can the et persist al. appears leading 2007, while, 2009 to sides be NGC pushed Wong of the 4501 & ram from Kenney is pressure one a moderately-inclined 2014). compression )which 2005 of these are Chung galaxies highly-inclined, on et the al. are (Kenney The small ridges Hi spirals et gas likely al. should Virgo 2011) “radio in be Atomic and noted deficit (3) that Hydrogen one-sided regions” NGC extraplanar survey 4330, (Murphy NGC (VIVA et 4402 al. Kenney of 2004, Hi ram from 2007, 2006, pressure the 2008 2008) VLA Abramson stripping. degrees for in 2009) our the sample ( form ∼ (2) 0.4–0.9 of: young of (1) galaxies Mpc) one-sided stellar from from populations the ridges the cluster Sloan of enhanced center in Digital their where gas- Sky po- stripped many Survey larized galaxies radio (SDSS) outer continuum stellar exhibit overlaid disks evidence with (Vollmer (Crowl contours for et & ongoing al. disks All Evidence Figure 1 (Koopmann four spirals shows of ongoing & are three-color Kenney approximately ram pressure 2004 optical Chung 1.5–3.3 is images present et al. The Hi gas morphology in each of these galaxies appears to be pushed from one side and lop-sided while the optical stellar disk appears unaffected. Figure 1 shows three-color optical images for our sample of galaxies from the Sloan Digital Sky Survey (SDSS) overlaid with contours of Hi from the VLA Imaging of Virgo in Atomic Hydrogen survey (VIVA Chung et al. NGC 4402 and NGC 4522 each have strong polarized ridges and strong radio deficit regions. Beyond the polarized ridges, local radio deficit regions are found in ram pressure affected galaxies where the densities of cosmic ray electrons and magnetic fields are lower than in undisturbed galaxies. The polarized ridges likely indicate ISM compression on the leading sides of the ram pressure interactions (Vollmer et al. 2004, 2007, 2008) and (2) one-sided “radio deficit regions” (Murphy et al. of ongoing ram pressure is present in the form of: (1) one-sided ridges of enhanced polarized radio continuum (Vollmer et al.
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