Simulating the shocks in the dissociative galaxy cluster Abell 1758N

Autor(es)

Machado, R. E. G. ^{[1, 2]} ; Monteiro-Oliveira, R. ^[1] ; Lima Neto, G. B. ^[1] ; Cypriano, E. S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo - Brazil

^[2] Univ Andres Bello, Dept Fis & Ciencia Mat, Dept Ciencias Fis, Santiago - Chile

• Tipo de documento: Artigo Científico
• Fonte: Monthly Notices of the Royal Astronomical Society; v. 451, n. 3, p. 3309-3320, AUG 11 2015.
• Citações Web of Science: 8

Resumo

Major mergers between massive clusters have a profound effect in the intracluster gas, which may be used as a probe of the dynamics of structure formation at the high end of the mass function. An example of such a merger is observed at the northern component of Abell 1758, comprising two massive sub-clusters separated by approximately 750 kpc. One of the clusters exhibits an offset between the dark matter and the intracluster gas. We aim to determine whether it is possible to reproduce the specific morphological features of this cluster by means of a major merger. We perform dedicated SPH (smoothed particle hydrodynamics) N-body simulations in an attempt to simultaneously recover several observed features of Abell 1758, such as the X-ray morphology and the separation between the two peaks in the projected galaxy luminosity map. We propose a specific scenario for the off-axis collision of two massive clusters. This model adequately reproduces several observed features and suggests that Abell 1758 is seen approximately 0.4 Gyr after the first pericentric passage, and that the clusters are already approaching their maximum separation. This means that their relative velocity is as low as 380 km s(-1). At the same time, the simulated model entails shock waves of similar to 4500 km s(-1), which are currently undetected presumably due to the low-density medium. We explain the difference between these velocities and argue that the predicted shock fronts, while plausible, cannot be detected from currently available data. (AU)

• Processo FAPESP: 09/54006-4 - Um cluster de computadores para o Departamento de Astronomia do IAG-USP e para o Núcleo de Astrofísica da UNICSUL
• Beneficiário: Elisabete Maria de Gouveia Dal Pino
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 14/13723-3 - Aglomerados de galáxias como portais para o universo escuro
• Beneficiário: Eduardo Serra Cypriano
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 10/12277-9 - Simulações numéricas de colisões de aglomerados de galáxias
• Beneficiário: Rubens Eduardo Garcia Machado
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado