Observing the millimeter Universe with the NIKA2 camera

Session

NIKA2-polarization

5 juin 2019, 13:30

37. Magnetic fields in star-forming filaments: NIKA2-POL as a pathfinder for SPICA-B-BOP

Dr Philippe André (CEA Saclay)

05/06/2019 13:30

Herschel imaging surveys of Galactic molecular clouds have emphasized the quasi-universality of the filamentary structure of the cold ISM and the key role of filaments in the star formation process. Planck polarization data moreover suggest that the formation and evolution of star-forming filaments is at least partly controlled by magnetic fields. I will summarize the main objectives...

32. Observing with NIKA2Pol from the 30m telescope. Early results on the commissioning phase.

Dr Alessia Ritacco (IRAM - Granada)

05/06/2019 14:00

NIKA2 is equipped with a polarization system composed by a multi-mesh half wave plate (HWP) and a polarizer placed at the cryostat stage of 100 mK which transmits and re ects the two orientation of the linear polarization on two 1mm KID-arrays. The polarizer is needed because the NIKA2 detectors KIDs are unsensitive to the polarization, the warm HWP placed in front of the cryostat window...

35. Preliminary results from the NIKA2-Pol commissioning : Analyzing and correcting for instrumental polarization

M. Hamza AJEDDIG (Département d’Astrophysique (AIM), CEA Saclay, 91191 Gif-sur-Yvette, France)

05/06/2019 14:30

Highlighting the role of magnetic fields in the star formation process is crucial. Observations have already shown that magnetic fields play an important role in the early stages of star formation. The high spatial resolution (~0.01 to 0.05 pc) provided by NIKA2-Pol 1.2 mm polarimetric imaging of nearby clouds will help us to start clarifying the geometry of the B field within dense cores and...

43. In-depth multiscale analysis of polarisation maps

Dr Jean-François Robitaille (IPAG - Univ. Grenoble Alpes)

05/06/2019 14:55

Observations of the polarised dust emission with Planck and the future SPICA at large scale and with ALMA, SCUBA2 and NIKA2 at smaller scales trace the interaction between the magnetic field and the denser part of the ISM as molecular clouds and star formation regions. However, a clear interpretation of the Stokes parameters Q and U, and of the associated polarisation vector P, is difficult....

27. The NIKA polarimeter on science targets: Crab nebula observations at 150 GHz and dual-band images of Orion Molecular Cloud OMC-1

Dr Alessia Ritacco (IRAM - Granada)

05/06/2019 15:55

NIKA, the NIKA2 pathnder, was equipped of a room temperature polarization system (a half wave plate and a grid polarizer facing the cryostat window). This polarization system was the test bench for the NIKA2 polarimeter and was used during few observational/technical campaigns between 2014 and 2015. In particular during the last observing week of NIKA at the IRAM 30m telescope, in February...

16. Absolute calibration of the polarisation angle for future CMB B-mode experiments from current and future measurements of the Crab nebula

M. Jonathan Aumont (LPSC)

05/06/2019 16:25

A tremendous international effort is currently dedicated to observing the so-called primordial $B$ modes of the Cosmic Microwave Background (CMB) polarisation. If measured, this faint signal imprinted by the primordial gravitational wave background, would be an evidence of the inflation epoch and quantify its energy scale, providing a rigorous test of fundamental physics far beyond the reach...

51. Analysis of Galactic molecular clouds polarization maps: a review of the methods

Frédérick Poidevin (IAC)

05/06/2019 16:55

Galactic molecular clouds are made of subparsec scale filamentary structures in which star formation occurs. The role of the magnetic fields in the formation and evolution of such structures leading to the formation of prestellar cores is still poorly understood, one reason being the lack of resolution provided by current and previous experiments. By measuring the linear polarized emission of...

53. Impact of B field in building clouds filaments and their hosted high-mass stars

Frédérique Motte (IPAG)

05/06/2019 17:25

Star formation is a key process in astrophysics. At large scale, it regulates the energy budget of galaxies (especially massive stars) while at a small scale it sets the initial conditions for planet formation. It has been shown that the formation of stars, and the nature of the stars that will be formed, is very sensitive to the physical conditions at the cloud scale. Hence, star formation is...