Browsing by Author "Firpo, V."

Now showing 1 - 3 of 3
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    A colour-excess extinction map of the southern Galactic disc from the VVV and GLIMPSE surveys
    (2019) Soto, M.; Barba, R.; Minniti, D.; Kunder, A.; Majaess, D.; Nilo Castellon, J. L.; Alonso García, J.; Leone, G.; Contreras Ramos, Rodrigo Andrés; Hempel, Maren; Morelli, Lorenzo; Haikala, L.; Firpo, V.; Lucas, P.; Emerson, J. P.; Bidin, C. M.; Geisler, D.; Saito, R. K.; Gurovich, S.; Rejkuba, M.; Barbieri, M.; Román Lopes, A.; Alonso, M. V.; Baravalle, L. D.; Borissova, J.; Kurtev, R.; Milla, F
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    A SUBMILLIMETER STUDY OF THE IR DUST BUBBLE S 21 AND ITS ENVIRONS
    (UNIV NACIONAL AUTONOMA MEXICO, INST DE ASTRONOMIA, 2017) Cappa, C. E.; Duronea, N. U.; Vasquez, J.; Rubio, M.; Firpo, V.; Lopez Caraballo, C. H.; Borissova, J.
    Based on the molecular emission in the (CO)-C-12(2-1) and (CO)-C-13(2-1) lines, and on the continuum emission in the MIR and FIR towards the S 21 IR dust bubble, we analyze the physical characteristics of the gas and dust linked to the nebula and the presence of young stellar objects (YSOs) in its environs. The line emission reveals a clumpy molecular shell, 1.4 pc in radius, encircling S 21. The total molecular mass in the shell amounts to 2900 M-circle dot and the original ambient density, 2.1 x10(3) cm(-3), indicating that the bubble is evolving in a high density interstellar medium. The image at 24 mu m shows warm dust inside the bubble, while the emission in the range 250 to 870 mu m reveals cold dust in its outskirts, coincident with the molecular gas. The detection of radio continuum emission indicates that the bubble is a compact Hii region. A search for YSOs using photometric criteria allowed to identify many candidates projected onto the molecular clumps. We analize if the collect and collapse process has triggered a new generation of stars.
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    Clues on Arp 142: The spiral–elliptical merger
    (OUP, 2019) Mora, Marcelo D.; Torres-Flores, S.; Firpo, V.; Hernandez-Jimenez, J. A.; Urrutia-Viscarra, F.; Mendes de Oliveir, C.
    Nearby merging pairs are unique laboratories in which one can study the gravitational effects on the individual interacting components. In this manuscript, we report the characterization of selected H II regions along the peculiar galaxy NGC 2936, member of the galaxy pair Arp 142, an E+S interaction, known as ‘The Penguin’. Using Gemini South spectroscopy, we have derived a high enhancement of the global star formation rate (SFR) = 35.9 M ⊙ yr −1 probably stimulated by the interaction. Star-forming regions on this galaxy display oxygen abundances that are consistent with solar metallicities. The current data set does not allow us to conclude any clear scenario for NGC 2936. Diagnostic diagrams suggest that the central region of NGC 2936 is ionized by active galactic nucleus (AGN) activity and the eastern tidal plume in NGC 2936 is experiencing a burst of star formation, which may be triggered by the gas compression due to the interaction event with its elliptical companion galaxy: NGC 2937. The ionization mechanism of these sources is consistent with shock models of low velocities of 200–300 km s  −1 . The isophotal analysis shows tidal features on NGC 2937: at inner radii non-concentric (or off-centring) isophotes, and at large radii, a faint excess of the surface brightness profile with respect to de Vaucouleurs law. By comparing the radial velocity profiles and morphological characteristics of Arp 142 with a library of numerical simulations, we conclude that the current stage of the system would be about 50 ± 25 Myr after the first pericentre passage.