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We present observations of the optical and X-ray emission from the Galactic supernova remnant W51C. From [S ii] Fabry–Pérot interferometry and H α and [S ii] images we detect filaments that are part of the optical counterpart of the supernova remnant. We obtain the kinematic distance to W51C, showing that it is one of the shortest distances reported in the literature. We also estimate other physical properties such as the velocity of the shock induced in the cloudlets emitted at optical wavelengths and the electron density of those cloudlets. From XMM–Newton observatory archival data, we obtain images of the diffuse X-ray emission of this supernova remnant. The spectrum of the X-ray emission is explored to estimate X-ray parameters such as luminosity and temperature of the hot plasma in the supernova remnant. We fit a thermal model with a plasma temperature of 1.4 keV for an X-ray thermal luminosity of 2.0 × 1036 erg s−1. With the parameters described above we test the model proposed by White & Long to explain the mixed morphology observed in W51C. We obtain an initial energy of the supernova explosion of 8.4 × 1050 erg and an age of 13 000 yr. The derived initial energy is typical of supernova remnants, but in disagreement with respect to older estimations that found higher values and suggested that W51C was the result of the explosion of two supernovae.

We study the kinematics of the western optical filament of the radio shell W50 with imaging Fabry–Perot spectroscopy using the [S ii] (λ6717 Å and λ6731 Å) line doublet. The high [S ii]/H α line ratio of this filament, as well as the complexity of the radial velocity profiles obtained in this work ensure that this filament and diffuse regions are the optical counterpart of W50 hosting the peculiar object SS 433. We derive a kinematical distance of 4.7 ± 0.5 kpc, validating a previously derived distance based on the assumption that H i or CO gas is associated with W50. Our distance estimate is in agreement with the distance to SS 433 derived from proper motions. Shock velocities of up to 120 km s−1 are estimated for the [S ii] emitting regions. We derive an age between 1.0 and 1.9 × 105 yr considering that W50 is a remnant of a supernova explosion or a bubble blown by the action of the jets of the central SS 433 source, respectively. Age values are compatible with the age of SS 433. We also estimate the energy deposited by the supernova in the interstellar medium and alternatively, the luminosity of a wind-blown bubble fed by the relativistic jets of SS 433, obtaining reasonable values. We examine the different scenarios for the formation of W50. We conclude that a supernova remnant scenario rejuvenated by the interaction of SS 433 jets, acting as a piston, evolving in a three-phase medium with photo-evaporation, describes better the different observations and theoretical models of this system.

We present observations in X-ray and optical emission of the supernova remnant (SNR) 0520–69.4 in the Large Magellanic Cloud. Using XMM–Newton observatory data, we produced images of the diffuse X-ray emission and spectra to obtain the X-ray parameters, such as luminosity and temperature, of hot plasma in the SNR. Diffuse X-ray emission with filled-centre morphology goes beyond the Hα region, suggesting that the hot gas escapes through the pores of the Hα shell. We fitted a model that has a plasma temperature of 1.1 × 107 K for an X-ray thermal luminosity of 3.3 × 1035 erg s−1. However, from Hα and [O iii] Fabry–Perot observations obtained with the Marseille Hα Survey of the Magellanic Clouds and the Milky Way at La Silla, European Southern Observatory, we are able to obtain physical parameters such as the velocity of the shock induced in the cloudlets emitting at optical wavelengths and the electron density of this gas. With the parameters described above, we test the model proposed by White & Long (1991, ApJ, 373, 543) for explaining the mixed-morphology observed.

We present direct images in the H$\alpha$ and [SII]$\lambda \lambda$6717,6731 $\textA$ lines of the Galactic Supernova Remnant G109.1-1.0 (CTB 109). We confirm that the filaments detected are the optical counterpart of the X-ray and radio supernova remnant due to their high [SII]/H$\alpha$ line-ratios. We study for the first time the kinematics of the optical counterpart of SNR CTB 109 using the UNAM scanning Fabry-Perot interferometer PUMA. We estimate a systemic velocity of V$_{LSR}$=-50$\pm$6 km s$^{-1}$ for this remnant and an expansion velocity of V$_{exp}$=230$\pm$5 km s$^{-1}$. From this velocity value and taking into account previous studies about the kinematics of objects at that Galactic longitude we derive a distance to the SNR CTB 109 of 3.1$\pm$0.2 kpc, locating it in the Perseus arm. Using the [SII]$\lambda$6717/[SII]$\lambda$6731 line-ratio we find an electronic density value around n$_e$= 580 cm$^{-3}$. Considering that this remnant is evolving in a low density medium with higher density cloudlets responsible of the optical emission, we determine the age and energy deposited in the ISM by the supernova explosion (E$_0$) in both the Sedov-Taylor phase and the radiative phase. For both cases the age is of thousands of years and the E$_0$ is rather typical of SNRs containing simple pulsars so that, the energy released to the ISM cannot be used to distinguish between supernova remnants hosting typical pulsars from those hosting powerful magnetars as in the case of CTB 109.

International audience; We report the results of a kinematical H alpha survey of the Large Magellanic Cloud (LMC) presented in the form of a kinematical and photometric catalogue of 210 H ii regions. The observations have been obtained with a scanning Fabry-Perot interferometer that produced data cubes corresponding to 66 different pointings over this galaxy, each with a field of view of 38 arcmin, covering almost the whole extent of the LMC. We find a bimodal distribution of the H alpha luminosity of LMC H ii regions. We also derive the local star formation and star formation rate (SFR) per unit area of the nebulae, concluding that star formation in the LMC has proceeded until the present time at an average rate of roughly 0.11 M-aS (TM) yr(-1). Also, we do not find any correlation between the SFR or I (SFR) pound with Delta V (full width at half-maximum for a single Gaussian profile and the difference in velocities for multiple-components velocity profiles), the diameter, the distance to the kinematical centre of the LMC and age of the nebulae. Over most of the LMC Delta V appears to be of the order of 30 km s(-1). However, in a few regions the Delta V of the velocity profiles is as large as 50-100 kms(-1), corresponding to identified supernova remnants and superbubbles undergoing expansion motions.

Luminous infrared galaxies (LIRGs) are galaxies with LIR > 1011 L⊙. For a star-forming galaxy to emit at a LIRG level, it must have a very high star formation rate (SFR). In the local Universe, the star formation (SF) is primarily triggered by interactions. However, at intermediate redshift, a large fraction of LIRGs are disk galaxies with little sign of recent merger activity. The question arises whether the intermediate redshift LIRGs are “triggered” or experiencing “normal”, if elevated, SF. Understanding these SF processes is important since this type of systems may have contributed to 20% or more of the cosmic SFR in the early Universe. In order to address this issue we study similar systems in the Local Universe, that is isolated late-type galaxies displaying LIRG activity. We use different observational techniques in order to trace the star-forming history of these systems. Here we present preliminary results.

We present a study of the diffuse X-ray emission from superbubbles N 70 (DEM L301) and N 185 (DEM L25) located in the Large Magellanic Cloud, based on data from the XMM-Newton Satellite. We obtained spectra and images of these objects in the soft X-ray energy band. These X-ray spectra were fitted by a thermal plasma model, with temperatures of $2.6 \times 10^{6}$ K and $2.3 \times 10^{6}$ K, for N 70 and N 185, respectively. For N 70, images show that X-ray emission comes from the inner regions of the superbubble, when we compare the distribution of the X-ray and the optical emission; while for N 185, the X-ray emission is partially confined by the optical shell. We suggest that the observed X-ray emission is caused by shock-heated gas, inside of the optical shells. We also obtained X-ray luminosities which exceed the values predicted by the standard analytical model. This fact shows that, in addition to the winds of the interior stars, it is necessary to consider another ingredient in the description, such as a supernova explosion, as has been proposed in previous numerical models., 9 pages, 7 figures. Accepted for publication in AJ

"Se realiz ́o un estudio cinem ́atico del remanente de supernova gal ́actico G206.9+2.3 (PKS 0646+06) en las l ́ıneas [SII] λ 6717 y 6731 ̊ A. Este es uno de los primeros pasos de un proyecto a largo plazo de determinaci ́on de distancias cinem ́atica s a RSN gal ́acticos con contraparte ́optica. Se obtuvo la distancia cinem ́atica a es ta ne- bulosa, mostrando primero que los filamentos detectados son realmente la contra parte ́optica del RSN en radio. La distancia estimada en este trabajo es ligeramente may or que la distancia de Monoceros. Se estim ́o que G206.9+2.3 est ́a localizada a 2.2 kpc del Sol, en una regi ́on del cielo donde se observan varias nebulosas superpuestas a diferen- tes velocidades. Se midi ́o una velocidad de choque de 86 km s − 1 y un di ́ametro lineal de 18 pc. Finalmente se calcul ́o que la energ ́ıa depositada al medio interestelar p or la explosi ́on de supernova es de 1 . 7 × 10 49 ergs por lo que se concluy ́o que G206.9+2.3 est ́a en la fase radiativa de su evoluci ́on, con una edad de 6 . 4 × 10 4 a ̃nos."

We present the photometric and kinematic characterization of two groups, USGC U268 and USGC U376 located in different regions of the Leo cloud. U268, composed of 10 catalogued members and 11 new added members, has a small fraction (~24%) of early-type galaxies (ETGs). U376 has 16 plus 8 new added members, with ~38% of ETGs. We find the presence of significant substructures in both groups suggesting that they are likely accreting galaxies. U268 is located in a more loose environment than U376. For each member galaxy, broad band integrated and surface photometry have been obtained in far-UV and near-UV with GALEX, and in u,g, r, i, z (SDSS) bands. H_alpha imaging and 2D high resolution kinematical data have been obtained using PUMA Scanning Fabry-Perot interferometer at the 2.12 m telescope in San Pedro Martir, (Baja California, Mexico). We improved the galaxy classification and we detected morphological and kinematical distortions that may be connected to either on-going and/or past interaction/accretion events or environmental induced secular evolution. U268 appears more active than U376, with a large fraction of galaxies showing interaction signatures (60% vs. 13%). The presence of bars among late-type galaxies is ~10% in U268 and ~$29% in U376. The cumulative distribution of (FUV - NUV) colours of galaxies in U268 is significantly different than that in U376 with galaxies in U268 bluer than those in U376. In the (FUV-r vs. M_r) and (NUV-r vs. M_r) planes no members of U268 are found in the `red sequence', even early-type galaxies lie in the `blue sequence' or in the `green valley'. Most (80%) of the early-type members in U376 inhabits the `red sequence, a large fraction of galaxies, of different morphological types, are located in the `green valley', while the `blue sequence' is under-populated with respect to U268.

We use H scanning Fabry-Perot interferometric data on the Orion Nebula in order to study the proplyds of the central region. We find that Fabry-Perot interferometry constitutes an effective technique for the detection and identification of proplyds. Some of the proplyds and proplyd candidates become noticeable only after data processing of the Fabry-Perot velocity cubes. In addition, we present the H II region subtracted radial velocity profiles of most of the identified proplyds (13) and proplyd candidates (3). We estimate from these profiles their main kinematic properties. We find that all of them have velocities redshifted relative to the Orion nebular emission. The studied proplyds show typical values of mass loss and disk lifetimes and we discuss the implications of these values, taking into account the fact that this study is done over a large quantity of proplyds. Finally, we find that our velocity profiles suggest that a large fraction of proplyds have monopolar microjets.

We present H alpha observations of the isolated interacting galaxy pair NGC 5426/27 using the scanning Fabry-Perot interferometer PUMA. The velocity field, various kinematical parameters and rotation curve for each galaxy were derived. The FWHM map and the residual velocities map were also computed to study the role of non-circular motions of the gas. Most of these motions can be associated with the presence of spiral arms and structure such as central bars. We found a small bar-like structure in NGC 5426, a distorted velocity field for NGC 5427 and a bridge-like feature between both galaxies which seems to be associated with NGC 5426. Using the observed rotation curves, a range of possible masses was computed for each galaxy. These were compared with the orbital mass of the pair derived from the relative motion of the participants. The rotation curve of each galaxy was also used to fit different mass distribution models considering the most common theoretical dark halo models. An analysis of the interaction process is presented and a possible 3D scenario for this encounter is also suggested., Comment: 27 pages, 15 figures, to be published in Astronomy & Astrophysics

Evolutionary scenarios suggest that several mechanisms (from inner secular evolution to accretion/merging) may transform galaxy members, driving groups from an active star forming phase to a more passive, typical of dense environments. We are investigating this transition in a nearby group sample, designed to cover a wide range of properties (see also Marino et al. (2010), Bettoni et al. (2011) and Marino et al. (2012)). We study two groups, USGC U268 and USGC U376 located in different regions of the Leo cloud, through a photometric and kinematic characterization of their member galaxies. We revisit the group membership, using results from recent red-shift surveys, and we investigate their substructures. U268, composed of 10 catalogued members and 11 new added members, has a small fraction (~24%) of early-type galaxies (ETGs). U376 has 16 plus 8 new added members, with ~38% of ETGs. We find the significant substructuring in both groups suggesting that they are likely accreting galaxies. U268 is located in a more loose environment than U376. For each member galaxy, broad band integrated and surface photometry have been obtained in far-UV (FUV) and near-UV (NUV) with GALEX, and in u, g, r, i, z (SDSS) bands. Hα imaging and 2D high resolution kinematical data have been obtained using PUMA Scanning Fabry-Perot interferometer at the 2.12 m telescope in San Pedro Mártir (Baja California, México). We improved the galaxy classification and we detected morphological and kinematical distortions that may be connected to either on-going and/or past interaction/accretion events or environmental induced secular evolution. U268 appears more active than U376, with a large fraction of galaxies showing interaction signatures (60% vs. 13%). The presence of bars among late-type galaxies is ~10% in U268 and 29% in U376. The cumulative distribution of (FUV - NUV) colors of galaxies in U268 is significantly different (bluer) than that of U376's galaxies. Most (80%) of the early-type members in U376 inhabits the red sequence, a large fraction of galaxies, of different morphological types, are located in the green valley, while the blue sequence is under-populated with respect to U268.

We report the results of a kinematic Hα survey of the Large Magellanic Cloud (LMC) in the form of a kinematic and photometric catalogue of 210 HII regions, the radial velocity field of the ionized hydrogen in this galaxy, and the LMC Rotation Curve obtained from the velocity field. These data aim at understanding the LMC HII regions, bubbles and superbubbles in a global (galactic) scale so that we could have a 3D view and separate the rotation due to gravitational potential from other motions such as expansions.

We have been conducting a Fabry-Perot kinematic survey of ionized gas in the Magellanic Clouds in the Hα and [O III]λ5007 lines, using a 36-cm telescope at the European Southern Observatory. This poster presents our kinematic study of HII regions located at the northwestern parts of the LMC bar.