(Proposal ID) S16B-142

(PI) Tanaka, Yasuyuki

(Proposal Title)
Subaru IRCS linear polarimetry of magnetar 4U 0142+61

(Abstract)
The young, isolated neutron star 4U 0142+61 has a bright IR component that has 
been interpreted as emission from a supernova fallback disk around the star. 
The existence of such disks has long been suggested as they are the natural 
results of supernova fallback and probably are the missing link for planet 
formation around neutron stars. Here we propose Subaru/IRCS+AO linear 
polarimetry of 4U 0142+61 at K' band, for the further investigation of the 
candidate debris disk. If strong linear polarization (say 5-10%) is obtained, 
the debris disk interpretation would likely be rejected. On the other hand, 
very low polarization or a stringent upper limit would provide additional 
evidence for the existence of the debris disk. The latter would encourage a 
deep survey for debris disks around neutron stars with advanced IR telescopes 
in the near future.