TY  - JOUR
A1  - Leto, Paolo
A1  - Trigilio, C.
A1  - Oskinova, Lida
A1  - Ignace, R.
A1  - Buemi, C. S.
A1  - Umana, G.
A1  - Cavallaro, Francesco
A1  - Ingallinera, A.
A1  - Bufano, F.
A1  - Phillips, N. M.
A1  - Agliozzo, Claudia
A1  - Cerrigone, L.
A1  - Todt, Helge Tobias
A1  - Riggi, S.
A1  - Leone, Francesco
T1  - The polarization mode of the auroral radio emission from the early-type star HD 142301
JF  - Monthly notices of the Royal Astronomical Society
N2  - We report the detection of the auroral radio emission from the early-type magnetic star HD142301. New VLA observations of HD142301 detected highly polarized amplified emission occurring at fixed stellar orientations. The coherent emission mechanism responsible for the stellar auroral radio emission amplifies the radiation within a narrow beam, making the star where this phenomenon occurs similar to a radio lighthouse. The elementary emission process responsible for the auroral radiation mainly amplifies one of the two magneto-ionic modes of the electromagnetic wave. This explains why the auroral pulses are highly circularly polarized. The auroral radio emission of HD142301 is characterized by a reversal of the sense of polarization as the star rotates. The effective magnetic field curve of HD142301 is also available making it possible to correlate the transition from the left to the right-hand circular polarization sense ( and vice versa) of the auroral pulses with the known orientation of the stellar magnetic field. The results presented in this letter have implications for the estimation of the dominant magneto-ionic mode amplified within the HD142301 magnetosphere.
KW  - masers
KW  - polarization
KW  - stars: early-type
KW  - stars: individual: HD142301
KW  - stars: magnetic field
KW  - radio continuum: stars
Y1  - 2018
U6  - https://doi.org/10.1093/mnrasl/sly179
SN  - 0035-8711
SN  - 1365-2966
VL  - 482
IS  - 1
SP  - L4
EP  - L8
PB  - Oxford Univ. Press
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Zhang, Heshou
A1  - Yan, Huirong
T1  - Polarization of submillimetre lines from interstellar medium
JF  - Monthly notices of the Royal Astronomical Society
N2  - Magnetic fields play important roles in many astrophysical processes. However, there is no universal diagnostic for the magnetic fields in the interstellar medium (ISM) and each magnetic tracer has its limitation. Any new detection method is thus valuable. Theoretical studies have shown that submillimetre fine-structure lines are polarized due to atomic alignment by ultraviolet photon-excitation, which opens up a new avenue to probe interstellar magnetic fields. We will, for the first time, perform synthetic observations on the simulated three-dimensional ISM to demonstrate the measurability of the polarization of submillimetre atomic lines. The maximum polarization for different absorption and emission lines expected from various sources, including star-forming regions are provided. Our results demonstrate that the polarization of submillimetre atomic lines is a powerful magnetic tracer and add great value to the observational studies of the submilimetre astronomy.
KW  - polarization
KW  - turbulence
KW  - H II regions
KW  - ISM: magnetic fields
KW  - photodissociation region (PDR)
KW  - submillimetre: ISM
Y1  - 2017
U6  - https://doi.org/10.1093/mnras/stx3164
SN  - 0035-8711
SN  - 1365-2966
VL  - 475
IS  - 2
SP  - 2415
EP  - 2420
PB  - Oxford University Press
CY  - Oxford
ER  -