Observations and Simulation of N4676 ("The Mice" = Arp 242 = UGC 7938/9)

John Hibbard, NRAO

Observations:
• HI, Halpha & deep R-band observations
  see Hibbard & van Gorkom (1996), and Hibbard 1995, especially Appendix III, for details.
  • Image of NGC 4676 in the HI Rogues Gallery
  • R-band Image
  • Halpha Image
  • R + Halpha + HI
  • R-band (color) + HI (contours)
  • mpeg of HI cube (Thanks to the talents of the ATNF Visualisation Software group and the magic of karma, especially Tom Oosterloo and Richard Gooch)
  • False color RGB of optical (green), Halpha (white) and HI (blue)
  • HI moment1
  • Natural Weighted HI mom0+1
  • Natural weighted HI channel maps: A, B
  • L-V plot for N4676A (CD-array, NA wtg, 24")
  • L-V plot for N4676B (C-array, NA wtg, 16")
• CO observations:
  see Yun & Hibbard (2001) for details and postscript versions of these figures
  • CO on R-band, Halpha, and HI
  • CO channel maps on Halpha
  • CO mom0,1,2 maps (on Halpha)
  • HI (contours), CO (greys) position-velocity plot
  • HI, CO, Halpha Velocity Field
  • " , close up
  • ", with axis
• Unpublished
  • K-band Image
  • R-K Image
  • R+HI,B-R,R,K,R-K mosaic
  • Truecolor RGB optical images (.tif):
    v1=Full field of view
    v2=Close-up
    v3=full FOV, deeper
• HST ACS press release for The Mice:
  
  • IfA press release for models to go with ACS image
  • ACS Images
  • HST Press release text
  • Supporting animations (see also Simulations below and IfA press release)
  • NGC 4676 on the Astronomy Picture of the Day (5/6/02)

Simulations (J. Barnes, MNRAS, 2003, submitted. Hibbard & Barnes in prep):
Trade study done with Treecode, N=16,000, no gas. Optimized velocity field in 20 runs. High-res model run with N=2E20=1million particles. 4 runs varying Rperi. !!!WARNING!!! Work in progress!!
• Josh Barnes' webpage on Models of Interacting Galaxies
• mpeg of Simulation. Time evolution. From Josh Barnes' SAAS-Fee lectures.
• mpeg of Simulation Rotation of best match. Also from Josh Barnes' SAAS-Fee lectures.
• Josh Barnes' mpeg movie of high-resolution particle simulation.
• MPEG of fit of N-body data (red dots) to HI (blue circles) and CO (black circle):
  4 plane view (RA-Dec, Vz-Dec, RA-Vz, RA-z) (2.1MB mpg)
  4 plane view (RA-Dec, Vz-Dec, RA-Vz, RA-z) (0.9MB animated gif)
  2 plane view (RA-Dec, Vz-Dec (1.1MB mpg)
• Final N-body Fit to Observations
• Top view, different color coding
• N-body Time Evolution
• Modeling trade study (varying arguement of periapses only)
• 1 Million particle simulation
  • T=0.75 scale_r=86, scale_v=173
  • T=0.875 scale_r=78, scale_v=183
  • T=1.0 scale_r=62, scale_v=218
  • mom0 map of T=1
  • T=1.0, galaxies switched scale_r=60, scale_v=200
  • mom0 map of switched