| Texto completo | |
| Autor(es): |
Abraham, Zulema
;
Takeda, Larissa
;
Beaklini, Pedro P. B.
;
Diaz, Marcos
;
Page, Kim L.
;
Chomiuk, Laura
;
Linford, Justin D.
Número total de Autores: 7
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Monthly Notices of the Royal Astronomical Society; v. 527, n. 3, p. 13-pg., 2023-12-12. |
| Resumo | |
The shell of the classical nova V5668 Sgr was resolved by ALMA at the frequency of 230 GHz 927 d after eruption, showing that most of the continuum bremsstrahlung emission originates in clumps with diameter smaller than 10(15) cm. Using Very Large Array radio observations, obtained between days 2 and 1744 after eruption, at frequencies between 1 and 35 GHz, we modelled the nova spectra, assuming first that the shell is formed by a fixed number of identical clumps, and afterwards with the clumps having a power-law distribution of sizes, and were able to obtain the clump's physical parameters (radius, density, and temperature). We found that the density of the clumps decreases linearly with the increase of the shell's volume, which is compatible with the existence of a second media, hotter and thinner, in pressure equilibrium with the clumps. We show that this thinner media could be responsible for the emission of the hard X-rays observed at the early times of the nova eruption, and that the clump's temperature evolution follows that of the super-soft X-ray luminosity. We propose that the clumps were formed in the radiative shock produced by the collision of the fast wind of the white dwarf after eruption, with the slower velocity of the thermonuclear ejecta. From the total mass of the clumps, the observed expansion velocity and thermonuclear explosion models, we obtained an approximate value of 1.25 M-circle dot for the mass of the white dwarf, a central temperature of 107 K and an accretion rate from the secondary star of 10(-9) -10(-8) M-circle dot yr(-1). (AU) | |
| Processo FAPESP: | 14/07460-0 - Alvos para o LLAMA: estudo da variabilidade de rádio fontes em 43 GHz (banda 1) e busca por correlação com imagens interferométricas |
| Beneficiário: | Pedro Paulo Bonetti Beaklini |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 19/08341-8 - Sobre a massa de lítio ejetada em novas: uma análise atual |
| Beneficiário: | Larissa Takeda |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 22/02471-0 - Revisando abundâncias de envoltórios de novas |
| Beneficiário: | Larissa Takeda |
| Modalidade de apoio: | Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado |