Context. Close binary supersoft X-ray sources (CBSS) are binary systems that contain a white dwarf with stable nuclear burning on its surface. These sources, first discovered in the Magellanic Clouds, have high accretion rates and near-Eddington lumi
nosities (10^37 - 10^38 erg/s) with high temperatures (T = 2 - 7 x 10^5 K). Aims. The total number of known objects in the MC is still small and, in our galaxy, even smaller. We observed the field of the unidentified transient supersoft X-ray source RX J0527.8-6954 in order to identify its optical counterpart. Methods. The observation was made with the IFU-GMOS on the Gemini South telescope with the purpose of identifying stars with possible He II or Balmer emission or else of observing nebular extended jets or ionization cones, features that may be expected in CBSS. Results. The X-ray source is identified with a B5e V star that is associated with subarcsecond extended Halpha emission, possibly bipolar. Conclusions. If the primary star is a white dwarf, as suggested by the supersoft X-ray spectrum, the expected orbital period exceeds 21 h; therefore, we believe that the 9.4 h period found so far is not associated to this system.
NGC 7582 is defined as a Starburst/AGN galaxy, since its optical and X-Ray spectra reveal both characteristics. In this work, we show the results of a stellar population modeling in a datacube taken with the Gemini South telescope. We found that $sim
$ 90% of the light in the field of view is emitted by stars that are less than 1 billion years old. A strong burst occurred about $sim$ 6 million years ago and has nearly solar metallicity. We also found a Wolf-Rayet cluster.
NGC 7582 was identified as a Starburst galaxy in the optical cite[(Veron et al. 1981)]{Veron et al.(1981)} but its X-Ray emission is typical of a Seyfert 1 galaxy cite[(Ward et al. 1978)]{Ward et al.(1978)}. We analyzed a datacube of this object obta
ined with the GMOS-IFU on the Gemini-South telescope. After a subtraction of the stellar component using the {sc starlight} code cite[(Cid Fernandes et al. 2005)]{Cid Fernandes et al. (2005)}, we looked for optical signatures of the AGN. We detected a broad $Halpha$ component (figure ref{fig1}) in the source where cite[Bianchi et al.(2007)]{Bianchi et al.(2007)} identified the AGN in an HST optical image. We also found a broad $Hbeta$ feature (figure ref{fig2}), but its emission reveals a extended source. We suggest that it is the light of the AGN scattered in the ionization cone. We propose that NGC 7582 is a Seyfert 1 galaxy. A number of other hot-spots and Wolf-Rayet features were also identified.
Astronomy has evolved almost exclusively by the use of spectroscopic and imaging techniques, operated separately. With the development of modern technologies it is possible to obtain datacubes in which one combines both techniques simultaneously, pro
ducing images with spectral resolution. To extract information from them can be quite complex, and hence the development of new methods of data analysis is desirable. We present a method of analysis of datacube (data from single field observations, containing two spatial and one spectral dimension) that uses PCA (Principal Component Analysis) to express the data in the form of reduced dimensionality, facilitating efficient information extraction from very large data sets. PCA transforms the system of correlated coordinates into a system of uncorrelated coordinates ordered by principal components of decreasing variance. The new coordinates are referred to as eigenvectors, and the projections of the data onto these coordinates produce images we will call tomograms. The association of the tomograms (images) to eigenvectors (spectra) is important for the interpretation of both. The eigenvectors are mutually orthogonal and this information is fundamental for their handling and interpretation. When the datacube shows objects that present uncorrelated physical phenomena, the eigenvectors orthogonality may be instrumental in separating and identifying them. By handling eigenvectors and tomograms one can enhance features, extract noise, compress data, extract spectra, etc. We applied the method, for illustration purpose only, to the central region of the LINER galaxy NGC 4736, and demonstrate that it has a type 1 active nucleus, not known before. Furthermore we show that it is displaced from the centre of its stellar bulge.
