Utilizing NASA’s Swift spacecraft, a world staff of astronomers has found a luminous and slowly-evolving nuclear transient occasion. The origin of the newly detected transient, designated Swift J221951-484240, is but to be decided. The discovering was reported July 3 on the preprint server arXiv.
Nuclear astrophysics is essential to understanding supernova explosions, and particularly the synthesis of the chemical components that developed after the Large Bang. Subsequently, detecting and investigating nuclear transient occasions may very well be important so as to advance our information on this area.
Lately, a gaggle of astronomers led by Sam Oates of the College of Birmingham, U.Okay., has performed follow-up Swift observations of a gravitational wave alert generally known as S190930t so as to discover its electromagnetic counterpart. In end result, they recognized Swift J221951-484240 (or J221951 for brief) with Swift’s Extremely-Violet/Optical Telescope (UVOT).
“J221951 was found through the follow-up of a gravitational occasion: S190930t…. The supply seems nuclear when evaluating our ACS [Hubble Space Telescope’s Advanced Camera for Surveys] imagery to DES [Dark Energy Survey] photos going again to 2014,” the researchers defined.
J221951 was discovered at a spectroscopic redshift of 0.52, which guidelines out its affiliation with S190930t. At peak, J221951 was brighter than archival values in any respect ultraviolet, optical and infrared wavelengths, by greater than 1–3 magnitudes. The transient reached a peak absolute magnitude of -23 magazine and a peak bolometric luminosity of 1.1 quattuordecillion erg/s.
The total radiated vitality from J221951 was estimated to be about 26 sexdecillion erg. In accordance with the astronomers, this end result, along with the shortage of broad absorption strains within the optical spectrum, guidelines out the supernova explosion state of affairs for J221951.
Archival photometric knowledge for J221951 present a gradual rise previous to a peak close to the invention date. Furthermore, the brand new optical spectra of this transient are blue and comparatively featureless. Subsequently, based mostly on all the outcomes, Oates’ staff has labeled J221951 as a luminous and slow-evolving blue transient.
Attempting to find out the origin of J221951, the authors of the paper bear in mind two most believable hypotheses because the transient has properties in keeping with a tidal disruption occasion (TDE) and the turn-on of an lively galactic nucleus (AGN).
“The progenitor of J221951 is unclear. The optical and ultraviolet spectra present options resembling each TDEs and AGN. Total its spectral, temporal and host properties and its energetics are closest in nature to ASASSN-15lh and ASASSN-18jd. ASASSN-15lh, ASASSN-18jd and J221951 belong to an growing inhabitants of luminous blue transients, dubbed ambiguous nuclear transients for which the progenitors will not be properly constrained, however could also be TDEs or attributable to AGN exercise,” the researchers defined.
They added that additional observations of the late time evolution of J221951 might be essential so as to discover out which speculation is true.
Extra info:
S. R. Oates et al, Swift/UVOT discovery of Swift J221951-484240: a UV luminous ambiguous nuclear transient, arXiv (2023). DOI: 10.48550/arxiv.2307.01044
Journal info:
arXiv
© 2023 Science X Community
Quotation:
Astronomers uncover a luminous nuclear transient (2023, July 14)
retrieved 14 July 2023
from https://phys.org/information/2023-07-astronomers-luminous-nuclear-transient.html
This doc is topic to copyright. Other than any truthful dealing for the aim of personal examine or analysis, no
half could also be reproduced with out the written permission. The content material is offered for info functions solely.
