QUIJOTE CMB Experiment. Science goals

The QUIJOTE-CMB experiment has two primary scientific goals:

For these scientific objectives, QUIJOTE-CMB will conduct two large surveys in polarisation (i.e., Stokes Q and U maps):

According to these nominal sensitivities, QUIJOTE-CMB will provide one of the most sensitive 11–19GHz
measurements of the polarisation of the synchrotron and anomalous emissions on degree angular scales. This information is extremely important given that B-modes are known to be sub-dominant in amplitude as compared to the Galactic emission.

A forecast of the QUIJOTE Phase I and II results

Using the MFI maps, we plan to correct the high frequency QUIJOTE-CMB channels (30 and 40 GHz) to search for primordial B-modes. As an illustration, the two figures below presents two cases. The first panel shows the scientific goal for the angular power spectrum of the E and B modes after 1-year of effective observing time, assuming a sky coverage of 3000 square degrees, with the TGI only. In this particular case, the final noise level for the 30GHz map is ~0.5 μK/beam.

Phase I results

The bottom panel shows the scientific goal for the QUIJOTE-CMB Phase II. Here, we consider 3 years of effective observing time with the TGI, and 2 years with the FGI. Note that, once the two instruments (FGI and TGI) are available, they can be operated simultaneously, as we will have two telescopes.

 Phase II results

Characterization of the foreground emission

Using the low frequency QUIJOTE maps, we plan to correct the high frequency QUIJOTE channel (30 GHz) to search for primordial B-modes. The figure below shows the expected foreground contamination in the 30 GHz QUIJOTE frequency band. It is shown the contribution of polarized synchrotron emission and radio-sources for the case of subtracting sources down to 1 Jy in total intensity (upper dashed line for radio-sources) and 300 mJy (lower dashed-line).

Foregrounds

The next figure shows how the synchrotron emission at 30 GHz can be corrected. The magenta line shows the predicted synchrotron level from a simulation of the expected synchrotron signal. Assuming a pure power-law dependence for the synchrotron emission in the QUIJOTE frequency range, the blue line shows the synchrotron residual after correction using the low frequency channels (11 to 19 GHz).

Foreground Residuals