X-ray detection of a nova in the fireball phase
| Autor: | Ole König, Jörn Wilms, Riccardo Arcodia, Thomas Dauser, Konrad Dennerl, Victor Doroshenko, Frank Haberl, Steven Hämmerich, Christian Kirsch, Ingo Kreykenbohm, Maximilian Lorenz, Adam Malyali, Andrea Merloni, Arne Rau, Thomas Rauch, Gloria Sala, Axel Schwope, Valery Suleimanov, Philipp Weber, Klaus Werner |
|---|---|
| Přispěvatelé: | Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. GAA - Grup d'Astronomia i Astrofísica, Ministerio de Economía y Competitividad (España) |
| Jazyk: | angličtina |
| Rok vydání: | 2022 |
| Předmět: |
High-energy astrophysics
High Energy Astrophysical Phenomena (astro-ph.HE) Transient astrophysical phenomena High Energy Physics - Experiment (hep-ex) Multidisciplinary Física::Astronomia i astrofísica [Àrees temàtiques de la UPC] X-Rays FOS: Physical sciences Raigs X Astrophysics - High Energy Astrophysical Phenomena Compact astrophysical objects High Energy Physics - Experiment |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname |
| Popis: | Novae are caused by runaway thermonuclear burning in the hydrogen-rich envelopes of accreting white dwarfs, which results in the envelope to expand rapidly and to eject most of its mass. For more than 30 years, nova theory has predicted the existence of a "fireball" phase following directly the runaway fusion, which should be observable as a short, bright, and soft X-ray flash before the nova becomes visible in the optical. Here we present the unequivocal detection of an extremely bright and very soft X-ray flash of the classical Galactic nova YZ Reticuli 11 hours prior to its 9 mag optical brightening. No X-ray source was detected 4 hours before and after the event, constraining the duration of the flash to shorter than 8 hours. In agreement with theoretical predictions, the source's spectral shape is consistent with a black body of $3.27^{+0.11}_{-0.33}\times 10^5$ K ($28.2^{+0.9}_{-2.8}$ eV), or a white dwarf atmosphere, radiating at the Eddington luminosity, with a photosphere that is only slightly larger than a typical white dwarf. This detection of the expanding white dwarf photosphere before the ejection of the envelope provides the last link of the predicted photospheric lightcurve evolution and opens a new window to measure the total nova energetics. Comment: Published in Nature on 11 May 2022 |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|