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Register a new userThe Radio Structure of the Narrow-Line Seyfert 1 Mrk 783 with VLBA and e-MERLIN
إطار الراديو لسايفرت 1 مرك 783 مع VLBA و e-MERLIN
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بينما نحن في هذا البحث، نقدم تحليلا لملاحظات الراديو والبصرية الجديدة للمجرة الصغيرة الخطية سايفرت 1 مرك 783. ملاحظات 1.6 جيجاهرتز التي تم تنفيذها باستخدام مؤشر الاي-ميرلين تؤكد وجود الانبعاثات المتجانسة التي تم الكشف عنها مسبقا. كما أن مؤشر الطول الطويل الشبكي (VLBA) يكتشف المصدر النووي كلا في 1.6 جيجاهرتز (L-Band) و 5 جيجاهرتز (C-Band). بينما تظهر صورة L-Band فقط النواة الغير محددة، تظهر صورة C-Band وجود بنية جزئيا محددة، على زاوية الإحداث الطولي والعرضي 60 درجة. درجة حرارة الإشعاع في كلا الأطوال ($>10^6$ K) تشير إلى أنها جيت على مقياس بايكلوتر ينتج عن النظام النووي المشترك. في الوقت نفسه، يتوافق الفهرس الصوتي المتأخر في VLBA ($alpha_{VLBA} = 0.63pm0.03$) مع وجود الانبعاثات الشفافة البصرية على مقياس ميلي أركسيكوند. وأخيرا، قمنا بتحليل حالتين محتملتين التي يمكن أن تنتج عن الإزاحة بين البنية الراديوية على مقياس الكيلومترات والبنية الراديوية على مقياس البايكلوتر التي تم الكشف عنها في المجرة. كما قمنا بتحليل الشكل البصري للمجرة، الذي يشير إلى أن مرك 783 عاشت تجربة الدمج في الآونة الأخيرة.
In this paper, we present the analysis of new radio and optical observations of the narrow-line Seyfert 1 galaxy Mrk 783. 1.6 GHz observations performed with the e-MERLIN interferometer confirm the presence of the diffuse emission previously observed. The Very Long Baseline Array (VLBA) also detects the nuclear source both at 1.6 GHz (L-Band) and 5 GHz (C-band). While the L-band image shows only an unresolved core, the C-band image shows the presence of a partially resolved structure, at a position angle of 60{deg}. The brightness temperature of the emission in both bands ($>10^6$ K) suggests that it is a pc-scale jet produced by the AGN. The relatively steep VLBA spectral index ($alpha_{VLBA} = 0.63pm0.03$) is consistent with the presence of optically thin emission on milliarcsecond scales. Finally, we investigated two possible scenarios that can result in the misalignment between the kpc and pc-scale radio structure detected in the galaxy. We also analysed the optical morphology of the galaxy, which suggests that Mrk 783 underwent a merging in relatively recent times.
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