Busca avançada
Ano de início
Entree
(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Time-scales to reach chemical equilibrium in ices at snowline distance around compact objects: the influence of accretion mass in the central object

Texto completo
Autor(es):
Carvalho, G. A. [1] ; Pilling, S. [1]
Número total de Autores: 2
Afiliação do(s) autor(es):
[1] Univ Vale Paraiba UNIVAP, Inst Pesquisa & Desenvolvimento IP&D, Av Shishima Hifumi 2911, BR-12244000 Sao Jose Dos Campos, SP - Brazil
Número total de Afiliações: 1
Tipo de documento: Artigo Científico
Fonte: Monthly Notices of the Royal Astronomical Society; v. 503, n. 2, p. 2973-2978, MAY 2021.
Citações Web of Science: 0
Resumo

In this work, we analyse soft X-ray emission due to mass accretion on to compact stars and its effects on the time-scale to reach chemical equilibrium of eventual surrounding astrophysical ices exposed to that radiation. Reaction time-scales due to soft X-ray in water-rich and pure ices of methanol, acetone, acetonitrile, formic acid, and acetic acid were determined. For accretion rates in the range (m) over dot = 10(-12)-10(-8) M-circle dot yr(-1) and distances in the range 1-3 LY from the central compact objects, the time-scales lie in the range 10-10(8) yr, with shorter time-scales corresponding to higher accretion rates. Obtained time-scales for ices at snow-line distances can be small when compared to the lifetime (or age) of the compact stars, showing that chemical equilibrium could have been achieved. Time-scales for ices to reach chemical equilibrium depend on X-ray flux and, hence, on accretion rate, which indicates that systems with low accretion rates may not have reached chemical equilibrium. (AU)

Processo FAPESP: 09/18304-0 - Síntese e degradação de espécies moleculares pré-bióticas em atmosferas planetárias, cometas e gelos interestelares simulados
Beneficiário:Sergio Pilling Guapyassu de Oliveira
Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores