The first degree-scale starlight-polarization-based tomography map of the magnetized interstellar medium
Artikel i vetenskaplig tidskrift, 2024

We present the first degree-scale tomography map of the dusty magnetized interstellar medium (ISM) from stellar polarimetry and distance measurements. We used the RoboPol polarimeter at Skinakas Observatory to conduct a survey of the polarization of starlight in a region of the sky of about four square degrees. We propose a Bayesian method to decompose the stellar-polarization source field along the distance to invert the three-dimensional (3D) volume occupied by the observed stars. We used this method to obtain the first 3D map of the dusty magnetized ISM. Specifically, we produced a tomography map of the orientation of the plane-of-sky component of the magnetic field threading the diffuse, dusty regions responsible for the stellar polarization. For the targeted region centered on Galactic coordinates (l, b) (103.3, 22.3), we identified several ISM clouds. Most of the lines of sight intersect more than one cloud. A very nearby component was detected in the foreground of a dominant component from which most of the polarization signal comes and which we identified as being an intersection of the wall of the Local Bubble and the Cepheus Flare. Farther clouds, with a distance of up to 2 kpc, were similarly detected. Some of them likely correspond to intermediate-velocity clouds seen in H I spectra in this region of the sky. We found that the orientation of the plane-of-sky component of the magnetic field changes along distance for most of the lines of sight. Our study demonstrates that starlight polarization data coupled to distance measures have the power to reveal the great complexity of the dusty magnetized ISM in 3D and, in particular, to provide local measurements of the plane-of-sky component of the magnetic field in dusty regions. This demonstrates that the inversion of large data volumes, as expected from the PASIPHAE survey, will provide the necessary means to move forward in the modeling of the Galactic magnetic field and of the dusty magnetized ISM as a contaminant in observations of the cosmic microwave background polarization.

ISM: structure

ISM: magnetic fields

Dust, extinction

Polarization

Methods: statistical

Författare

V. Pelgrims

Panepistimio Kritis

Idryma Technologias kai Erevnas (FORTH)

Université libre de Bruxelles (ULB)

N. Mandarakas

Idryma Technologias kai Erevnas (FORTH)

Panepistimio Kritis

R. Skalidis

California Institute of Technology (Caltech)

Konstantinos Tassis

Idryma Technologias kai Erevnas (FORTH)

Panepistimio Kritis

Georgia Virginia Panopoulou

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

V. Pavlidou

Idryma Technologias kai Erevnas (FORTH)

Panepistimio Kritis

D. Blinov

Idryma Technologias kai Erevnas (FORTH)

Panepistimio Kritis

S. Kiehlmann

Idryma Technologias kai Erevnas (FORTH)

Panepistimio Kritis

S. E. Clark

Stanford University

Kavli Institute for Particle Astrophysics and Cosmology

Brandon S. Hensley

California Institute of Technology (Caltech)

S. Romanopoulos

Panepistimio Kritis

Idryma Technologias kai Erevnas (FORTH)

A. Basyrov

Universitetet i Oslo

H. K. Eriksen

Universitetet i Oslo

M. Falalaki

Idryma Technologias kai Erevnas (FORTH)

Panepistimio Kritis

T. Ghosh

Homi Bhabha National Institute (HBNI)

Inter-University Centre for Astronomy and Astrophysics

E. Gjerløw

Universitetet i Oslo

J. A. Kypriotakis

Panepistimio Kritis

Idryma Technologias kai Erevnas (FORTH)

S. Maharana

South African Astronomical Observatory

A. Papadaki

Panepistimio Kritis

Idryma Technologias kai Erevnas (FORTH)

Institute of Computer Science Crete

T. J. Pearson

California Institute of Technology (Caltech)

S. B. Potter

University of Johannesburg

South African Astronomical Observatory

A. N. Ramaprakash

Université libre de Bruxelles (ULB)

California Institute of Technology (Caltech)

Inter-University Centre for Astronomy and Astrophysics

A. C.S. Readhead

California Institute of Technology (Caltech)

I. K. Wehus

Universitetet i Oslo

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 684

Ämneskategorier

Astronomi, astrofysik och kosmologi

DOI

10.1051/0004-6361/202349015

Mer information

Senast uppdaterat

2024-05-13