Astron. Astrophys. 334, 409-419 (1998)
We filter the large scales of a map of CMB+moving lens fluctuations
(no SZ kinetic contribution) in order to test the robustness and
efficiency of the wavelet transform filtering. In this case, the noise
due to the CMB is efficiently cleaned. In fact, Fig. 6 lower left
panel shows a residual signal (symbolised by the dots) associated with
the moving lens fluctuations, which are simulated in the upper right
panel of the same figure. We have confirmed that the positions of the
residual signal agree with the positions of the input structures.
Moreover, we were able to successfully extract the secondary
fluctuations due to the moving lenses, as well as estimate their
average peak to peak values. Fig. 8 shows
the average peak to peak amplitudes of the input simulated
fluctuations (solid line) and the extracted values (dashed line). The
main features are well-recovered, although the amplitudes suffer from
the smoothing of the filtering procedure. In this study case, with no
SZ kinetic contribution, we find a correlation coefficient between
input and recovered values of about 0.95.
Fig. 6. The two upper panels show simulated maps: on the left, total map of the fluctuations (CMB+SZ+lens) linear scale between (white) and (black). On the right is shown the map of the moving lenses fluctuations (linear scale between (white) and (black)). The two lower panels are the result of the wavelet filtering process. The left panel is for a CMB+lens configuration, in which we notice that the secondary anisotropies are rather well extracted. The right panel represents the case of all contributors and shows that the moving lenses are completely dominated by the SZ kinetic noise.
Fig. 8. Average peak to peak amplitude of the secondary anisotropies due to the moving lenses (cut-off mass ) for lenses with decreasing y parameter. Solid line represents the amplitudes in the original simulated lens map. The dashed line represents the extracted amplitudes without sorting the wavelet coefficients and after filtering the CBM+lenses contributions (no SZ kinetic). The dotted-dashed line represents the extracted amplitudes after sorting the wavelet coefficients and filtering all contributions (CBM+lenses+SZ kinetic).
© European Southern Observatory (ESO) 1998
Online publication: May 15, 1998