Diffuse radio polarization, shocks, and large scale structure Lawrence Rudnick, University of Minnesota with Shea Brown, Jeff Lemmerman, Jenny Imholte, Joseph Barthel, Chris Benson E13-0002-08 13 July, 0955h, 515B

Shocks, WHIM and large scale structure The observational challenge Developing probes of diffuse emission - filtering - subtraction - polarization (and tantalizing pictures)

LSS = Shocks = Synchrotron

Local pressure radio surface brightness Mass distribution of shock heated gas (z=0) Kang, Ryu, Cen, Song 2005 ApJ 620, 21

Finding diffuse - filtering

Finding diffuse - subtraction

Abell 1367

Missing large scale

Polarized emission Large AND small scale

Faraday clouds at high latitude? ► (<P>800) new diffuse source candidate. Symbols: clusters of galaxies Gal et al. 2003 (AJ 125, 1064). ► Stokes Q image WSRT @ 350 MHz (see text to right), with (<P>800) contours overlayed. Green: ~0 rad/m2 Yellow: ~ 13 rad/ m2

Dead radio galaxy? ~ 500 kpc

Abell 119

Diffuse polarization – confirm and separate

Abell 907 + A 901, 902 supercluster ROSAT NVSS P 9’ resolution Stokes “U slices with GBT

Abell 576 DA240 “U” “Q”

Local pressure radio surface brightness Mass distribution of shock heated gas (z=0) Kang, Ryu, Cen, Song 2005 ApJ 620, 21