Sensitivity of a Bolometric Interferometer to the CMB power spectrum

Abstract

Context. The search for B-mode polarization fluctuations in the Cosmic Microwave Background is one of the main challenges of modern cosmology. The expected level of the B-mode signal is very low and therefore requires the development of highly sensitive instruments with low systematic errors. An appealing possibility is bolometric interferometry. Aims. We compare in this article the sensitivity on the CMB angular power spectrum achieved with direct imaging, heterodyne and bolometric interferometry. Methods. Using a simple power spectrum estimator, we calculate its variance leading to the counterpart for bolometric interferometry of the well known Knox formula for direct imaging. Results. We find that bolometric interferometry is less sensitive than direct imaging. However, as expected, it is finally more sensitive than heterodyne interferometry due to the low noise of the bolometers. It therefore appears as an alternative to direct imagers with different and possibly lower systematic errors, mainly due to the absence of an optical setup in front of the horns.

5 pages, 3 figures. This last version matches the published version (Astronomy and Astrophysics 491 3 (2008) 923-927). Sensitivity of Heterodyne Interferometers modified by a factor of two

References in corpus (6)

• Interferometric Observation of Cosmic Microwave Background Anisotropies
• The nature of the E-B decomposition of CMB polarization
• Observability of secondary Doppler peaks in the CMBR power spectrum by experiments with small fields
• Cosmic Microwave Background Anisotropy Observing Strategy Assessment
• Systematic Errors in Cosmic Microwave Background Interferometry
• Mosaicking with cosmic microwave background interferometers

Cited by in corpus (6)

• QUBIC: The QU Bolometric Interferometer for Cosmology
• Efficient decomposition of cosmic microwave background polarization maps into pure E, pure B, and ambiguous components
• Self-calibration: an efficient method to control systematic effects in bolometric interferometry
• An efficient phase-shifting scheme for bolometric additive interferometry
• Phase Shift Sequences for an Adding Interferometer
• Bandwidth in bolometric interferometry