اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدBowshocks in a newly discovered maser source in IRAS 20231+3440
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From measuring the annual parallax of water masers over one and a half years with VERA, we present the trigonometric parallax and corresponding distance of another newly identified water maser source in the region of IRAS 20231+3440 as $pi=0.611pm0.022$ mas and $D=1.64pm0.06$ kpc respectively. We measured the absolute proper motions of all the newly detected maser spots (30 spots) and presented two pictures describing the possible spatial distribution of the water maser as the morphology marks out an arc of masers whose average proper motion velocity in the jet direction was 14.26 km s$^{-1}$. As revealed by the ALLWISE composite image, and by applying the colour-colour method of YSO identification and classification on photometric archived data, we identified the driving source of the north maser group to be a class I, young stellar object. To further probe the nature of the progenitor, we used the momentum rate maximum value (1.2$times$10$^{-4}$ M$_{odot}$ yr$^{-1}$ km s$^{-1}$) of the outflow to satisfy that the progenitor under investigation is a low mass young stellar object concurrently forming alongside an intermediate-mass YSO $sim 60,000$ au ($sim 37$ arcsecs) away from it.
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