Document

Constraining the energetics and origin of cosmological fast radio bursts.

Source
Master's thesis
Other titles
دراسة توزبعات الطاقة والمصدر الإشعاعي للإنبعاثات الراديوية تاكونية السريعة مقارنة بالإنبعاثات المتوسطة للأشعة السينية من المجنتارات
Country
Oman
City
Muscat
Publisher
Sultan Qaboos University
Gregorian
2023
Language
English
Thesis Type
Master's thesis
English abstract
Fast Radio Bursts (FRBs) are extremely energetic (1029 -1032 J) short (millisecond) pulses of radio waves of cosmological origin that their progenitors and emission mechanism remain unsolved, although discovered more than a decade and a half ago. Extragalactic highly magnetized neutron stars (magnetars) are among the candidate progenitors of FRBs. The recent emission of an FRB and FRB-like bursts accompanied by X-Ray bursts from the galactic magnetar SGR 1935+2154 strengthened this proposition and called for a detailed scrutiny of the proposed association. Through this thesis we tackle this by studying a set of recurrent FRBs (that show a repeating behavior from the same location) together with similarly energetic X-ray bursts (intermediate flares) of confirmed magnetar origin. We utilized the first catalog of the Canadian Hydrogen Intensity Mapping Experiment (CHIME) radio observatory’s and identified 62 repeating extragalactic FRB in the 400-800 MHz frequency range, and 54 X-ray intermediate flares from five galactic magnetars. The duration (T), flux (F) and fluence (S) of the repeating FRBs showed lognormal distributions with means of 8.76 ± 1.00 ms, (3.15 ± 0.37) ×10−15 erg s−1 cm−2 and (2.76 ± 0.07) ×10−17 erg s−1 , respectively. Empirical relations between those quantities were found to follow the power-law relations: SF RB ∝ T 0.49 F RB and FF RB ∝ T −0.52 F RB . The X-ray intermediate flares showed similar lognormal trends for the same properties with their means given by 0.94 ± 0.06 s, (9.69 ± 0.69) × 10−6 erg s−1 cm−2 and (9.96 ± 0.65) × 10−6 erg cm−2 . The corresponding empirical correlations were found to be SIF ∝ T 0.67 IF and FIF ∝ T −0.32 IF . Our results favor the pulsar-like emission models that involve compact objects, such as neutron stars, over the cataclysmic event models that involve exploding stars or the merger of compact objects
Arabic abstract
الانبعاثات الراديوية السريعة (FRBs) هائلة الطاقة (1029 -1032 جول) هي نبضات لموجات قصيرة المدة (ملي ثانية) ذات اصل كوني لايزال مصدرها وآلية انبعاثها لغزا بدون حل.، على الرغم من مرور عقدونصف على اكتشافها . النجوم النيوترونية خارج المجرة الممغنطة بمجال مغناطيسي شديد (المجنتارات) من بين الأسلاف المقترحة FRBs. الانبعاث الأخير لـ FRB و
انفجارات تشبه FRB مصحوبة بانفجارات الأشعة السينية من النجم المغناطيسي المجري SGR
Category
Theses and Dissertations