Polarimetry at submillimeter and microwave wavelengths
Instituto de Astrofísica de Canarias
The first part of the talk will focus on submillimeter polarimetry of molecular clouds and star-forming regions in our galaxy. What are the exact processes leading to the formation of stars is still poorly understood. Our knowledge on the subject depends on our understanding of the nature of molecular clouds which can be tested by comparing observed maps with numerical simulations. In this context I will present an extensive analysis of the 850 microns (353 GHz) polarization maps of the SCUBA Polarimeter Legacy (SCUPOL) Catalogue produced by Matthews et al., focusing on the molecular clouds and star-forming regions. Conclusions regarding how simple, ideal, isothermal, and non-self-gravitating MHD simulations may be sufficient in order to describe the large-scale observed physical properties of some molecular cloud will be given. Additional analysis of submillimeter polarimetry data and continuum data respectively obtained, in the Lupus I molecular clouds, with the BLASTPol balloon-borne experiment, and with the Herschel-SPIRE will be discussed in this framework. The second half of the talk will focus on polarimetry at microwave wavelengths. I will give an overview of the QUIJOTE-CMB experiment based in the Canary Islands. QUIJOTE is a new CMB experiment aimed at characterizing the low-frequency polarized foregrounds and to detect the primordial B-mode signal down to a sensitivity on the tensor to scalar ratio of r=0.05. The first QUIJOTE telescope and its first instrument, the Multi-Frequency Instrument (MFI), observing in four bands between 10 GHz and 20 GHz are operative since november 2012. The maps provided by the MFI will provide valuable information about the polarization properties of the synchrotron emission, of anomalous microwave emission (AME) and of radio-sources. I will present preliminary results of the observation campaign with the MFI. I will also discuss the status of the second telescope and of a second instrument currently in their commissioning phase.
Date: Jeudi, le 8 janvier 2015 Heure: 11:30 Lieu: Université de Montréal Pavillon Roger-Gaudry, Local D-460 Contact: Pierre Bastien