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http://www.eso.org/science/healpix/

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... context

The signal entering at angles larger than $\sim$ $1^\circ$ from the beam centre direction produces the so-called straylight contamination, dominated by the Galactic emission (see e.g. Burigana et al. 2001, 2003), a systematic effect different from the main beam distortion effect considered in this work.

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... $T_{\rm s}$ )

For simplicity, all the convolutions between the beam and the sky map are centred about the nodes of the underlying pixelization. We have verified that this slightly improves the deconvolution accuracy and has to be then considered as an "ideal'' best case for our code. This working condition will be no longer employed in Sects. 3.3 and 3.4 where the P LANCK data sampling is considered.

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...

We observe that an analogous approach can be pursued also in the presence of correlated noise, provided that the noise properties can be known from laboratory measures and/or directly reconstructed from the data (Natoli et al. 2002). Of course, in this context, destriping (or, possibly, map-making, see e.g. Natoli et al. 2001) should be previously applied both to the data and to the simulated pure noise data.

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... time

In the current implementation, about 19 hours of computation are required to deconvolve a single patch with 1024² pixels on an 64 bit alpha digital unix machine with single cpu at 533 MHz and 1 Gb RAM.

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... noise

For example, the average sensitivity on a polar region of about 25 squared degrees is about 5 times better (i.e. $\simeq 2~ \mu$ K on pixel of 3.43'!) than the average full sky sensitivity: then, we expect there a deconvolution quality intermediate between that found here and that found in the previous section.

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... here

On the other hand, we have to keep in mind that a faithful recovery of the very high multipole tail of the CMB angular power spectrum requires to catch also with all the other, possibly coupled, systematics and a very accurate separation of the astrophysical foregrounds.

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... $360^\circ$

We note that, in other conventions, angles $\phi'_B$ and $\psi'_B$ ranging from $-180^\circ$ to $180^\circ$ are given, instead of $\phi_B$ and $\psi_B$ . The angles $\phi_B$ and $\psi_B$ here defined are equal to $\phi'_B$ and $\psi'_B$ when they are positive and are given respectively by $360^\circ + \phi'_B$ and $360^\circ + \psi'_B$ for negative $\phi'_B$ and $\psi'_B$ .

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