21cm tomography around QSO

21cm QSO

21-cm emission and absorption against the CMB from the region surrounding a quasar source (lower right corner, in the center of an HII region), revealed once the IGM is heated above the CMB by soft X-rays from the quasar. The linear size of the volume is 20h-1 (comoving) Mpc, the angular resolution is 2 arcmin, and the bandwidth is 1 MHz. The color levels range from -3 &mu Jy to 3 &mu Jy per beam. The dark contour demarcates the absorption ring. The quasar turns on at z = 8.5 with an ionizing photon luminosity of 1057 photons s-1, and is observed after 10 Myr. The temperature of the IGM beyond the light radius is assumed to be TK = 26 mK (1+z)2 = 2.3 K < TCMB. (From Tozzi et al. 2000.)

Return to 21cm signature of the IGM