Name: Vera A. F. Martin

Institution: UEFS, Departamento de Fisica

e-mail: vmartin1963(no-spam)hotmail.com

Partner Contry: BRA

Science Meeting: Yes

User Meeting: Yes

NGO Staff Meeting: No

Presentation: Yes

Format: Poster

Title: Fine structure and broad-band photometry of the peculiar galaxy ESO 287-G40

Co-author: Faundez-Abans, M. (1), de Oliveira-Abans, M. (1), Poppe, P.C.R. (2,3), Rodriguez Ardila, A (1), Wenderoth, E. (4)

Co-authors' Institutions: (1)MCT/LNA, (2)UEFS, Departamento de Fisica, (3)UEFS, Observatorio Astronomico Antares, (4)Gemini South

Abstract:

We report the results of broad-band imagery of the tidally disturbed galaxy ESO 287-G40, observed with both GMOS-S at Gemini South and direct CCD camera at Observatorio do Pico dos Dias MCT/LNA, Brazil. The object shows clear signatures of tidal perturbations, i.e., two rings (one of them resembling a perturbed arm-like structure), a large visible envelope surrounding the whole galaxy, and a smooth tidal filament to the SE. Some smaller structures have also been highlighted using the GMOS images. A second nucleus-like object is visible on the SW of the ESO 287-G40 nucleus. The B-R versus B-V diagnostic diagram shows that the NE section of the external ring is populated with well-defined H II regions (active star-forming clumps) and is bluer and clumpier than the SW region, which is redder and smoother, without clear evidences of H II regions. Both rings are evidences of dramatic double triggering of starbursts due to density wave shocks throughout the galactic disk. The internal ring is redder than the external one, and the nucleus is redder than the secondary nucleus-like object. The smooth tidal filament to the SE shows evidences of young and old populations mixture, suggesting star and gas whirlwinds triggered by tidal interaction. We present the results of surface photometry, galaxy mass calculations and estimated dimensions of the highlighted structures.