Doctoral theses
Current Record: 30 of 171
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Identifier |
000428287 |
Title |
Ultra-luminous X-ray sources and X-ray luminosity scaling relations in nearby galaxies |
Alternative Title |
Υπέρλαμπρες πηγές ακτίνων-Χ και σχέσεις κλίμακας λαμπρότητας ακτίνων-Χ σε κοντινούς γαλαξίες |
Author
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Αναστασοπούλου, Κωνσταντίνα Δ.
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Thesis advisor
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Ζέζας, Ανδρέας
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Reviewer
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Παυλίδου, Βασιλική
Pablo, Reig
Χαρμανδάρης, Βασίλης
Παπαδάκης, Ιωσήφ
Κυλάφης, Νικόλαος
Γεωργακάκης, Αντώνιος
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Abstract |
X-ray binaries (XRB) and their most extreme manifestation Ultra-luminous X-ray
sources (ULXs), are the dominant source of the hard X-ray emission in star-forming
galaxies. X-ray scaling relations between the luminosity of the XRB population, the
star-formation rate (SFR), and stellar mass (M*) have served as an important tool for
measuring the XRB component of any galaxy in the local Universe. Moreover, they
have been used to set observational constrains to the population synthesis models of
XRBs and their formation and evolution parameters. In this thesis, we have striven to answer the question of whether these correlations
are universal and representative of galaxies in the local Universe irrelevant of their
conditions (e.g. SFR, M*). For this reason we test the scaling relations of XRBs on
one of the most extreme, highly star-forming galaxies Arp 299 and explore their validity
at sub-galactic scales for the ULX-rich galaxies NGC3310 and NGC2276 using Chandra
data.
Moreover, using the XMM-Newton archive we build the largest X-ray sample of
bona-fide normal galaxies observed in the X-ray band (650 objects). This sample is
drawn from a complete sample of galaxies within 200Mpc and it encompasses the
full range of SFR and M* observed in the local Universe. With this sample of local
star-forming galaxies, we measure the XRB-SFR, XRB-M* scaling relations, and their
intrinsic scatter. We find that the X-ray luminosity-SFR scaling relation for the full
sample of normal local galaxies is sub-linear. This is most likely the result of contribution
from ULX-hosting galaxies and/or LMXBs in the low SFR regime. On the other
hand the X-ray luminosity-SFR-M* scaling relation, is consistent with the relations
reported for smaller samples, but with larger intrinsic scatter. The increased scatter
is interpreted as the result of the wider range of different types of galaxies (i.e. stellar
population ages, metallicity) covered by the full sample in comparison to the previous
smaller scale surveys.
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Language |
English |
Subject |
Galaxy ARP299 |
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Galaxy NGC2276 |
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Galaxy NGC3310 |
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X-ray binaries |
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Γαλαξίας ARP299 |
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Γαλαξίας NGC2276 |
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Γαλαξίας NGC3310 |
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Διπλά αστρικά συστήματα εκπομπής ακτίνων Χ |
Issue date |
2020-02-24 |
Collection
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School/Department--School of Sciences and Engineering--Department of Physics--Doctoral theses
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Type of Work--Doctoral theses
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Permanent Link |
https://elocus.lib.uoc.gr//dlib/2/0/f/metadata-dlib-1581932378-285682-6509.tkl
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Views |
1012 |