![Izquierda - Imagen RGB de la nebulosa de Orión y M43 obtenida filtros estrechos con la cámara WFC en el INT: H alfa (rojo), [S II] 6716+30 (verde), [O III] 5007 (azul). Derecha - Imagen en falso color de la nebulosa planetaria NGC 6778. En azul se ve la emisión en la línea de O II tomada con el filtro sintonizable azul del instrumento OSIRIS en el GTC; en verde imagen con el filtro estrecho de [O III] del Nordic Optical Telescope (NOT).](https://webpro-cms.ll.iac.es/sites/default/files/styles/color/public/images/project/imagen_web.jpg?itok=mgPK3oTc "Izquierda - Imagen RGB de la nebulosa de Orión y M43 obtenida filtros estrechos con la cámara WFC en el INT: H alfa (rojo), [S II] 6716+30 (verde), [O III] 5007 (azul). Derecha - Imagen en falso color de la nebulosa planetaria NGC 6778. En azul se ve la emisión en la línea de O II tomada con el filtro sintonizable azul del instrumento OSIRIS en el GTC; en verde imagen con el filtro estrecho de [O III] del Nordic Optical Telescope (NOT).")
Start year
1986
Organizational Unit
Organizing institutions
General
Description
The research that is being carried out by the group can be condensed into two main lines:
1) Study of the structure, dynamics, physical conditions and chemical evolution of Galactic and extragalactic ionized nebulae through detailed analysis and modelization of their spectra. Investigation of chemical composition gradients along the disk of our Galaxy and in nearby galaxies.
2) Determine the physical-chemical conditions of galactic planetary nebulae with bipolar geometry and nebulae around symbiotic stars. The aim is to understand the origin of bipolarity and to test theoretical models that attempt to explain nebular morphology and kinematics, with special emphasis on models with central binary stars. We will also study the implications of the evolution of binary systems in other astrophysical scenarios, such as the formation of jets, cataclysmic variables, and nova and supernova-type explosions.
Members
Principal investigator
Jorge
García Rojas
Project manager
César
Esteban López
Project staff
David
Jones
Antonio
Mampaso Recio
Collaborators
Dr.
Miguel Cerviño Saavedra
Dr.
A.R. López Sánchez
Dr.
F. Bresolin
Dr.
G. Delgado Inglada
Dr.
G. Domínguez Guzmán
Dr.
X. Fang
Dr.
N.C. Sterling
Dr.
R. Wesson
Dr.
H. Monteiro
Dr.
H. Boffin
Dra.
Karla Z. Arellano Córdoba
Dr.
M. Miller Bertolami
Dra.
Grazyna Stasinska
Dr.
T. Hillwig
Dr.
B. Miszalski
Dr.
M. Santander García
Dra.
E. Villaver
Dra.
L. Magrini
Dr.
S. Akras
Prof.
J. Drew
Prof.
B. Balick
Dr.
D. R. Gonçalves
Dra.
K. Kwitter
Dr.
A. Prsa
Results
- Using EMIR/GTC spectra in the near infrared range, tellurium and bromine emission lines have been detected for the first time in two planetary nebulae. These heavy element detections in one of their places where they are formed, give us information about the abundance patterns of heavy elements owing to the r-process and the s-process.
Scientific activity
Related publications
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Crucial aspects of the initial mass function. I. The statistical correlation between the total mass of an ensemble of stars and its most massive starContext. Our understanding of stellar systems depends on the adopted interpretation of the initial mass function, IMF φ(m). Unfortunately, there is not a common interpretation of the IMF, which leads to different methodologies and diverging analysis of observational data. Aims: We study the correlation between the most massive star that a clusterCerviño, M. et al.
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52013 -
Crucial aspects of the initial mass function. II. The inference of total quantities from partial information on a clusterContext. In a probabilistic framework of the interpretation of the initial mass function (IMF), the IMF cannot be arbitrarily normalized to the total mass, ℳ, or number of stars, N, of the system. Hence, the inference of ℳ and N when partial information about the studied system is available must be revised (i.e., the contribution to the totalCerviño, M. et al.
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52013 -
Characterization of a Sample of Intermediate-type Active Galactic Nuclei. II. Host Bulge Properties and Black Hole Mass EstimatesWe present a study of the host bulge properties and their relations with the black hole mass for a sample of 10 intermediate-type active galactic nuclei (AGNs). Our sample consists mainly of early-type spirals, four of them hosting a bar. For 70+10 –17% of the galaxies, we have been able to determine the type of the bulge, and find that theseBenítez, Erika et al.
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22013 -
Characterization of a Sample of Intermediate-type AGNs. I. Spectroscopic Properties and Serendipitous Discovery of New Dual AGNsA sample of 10 nearby intermediate-type active galactic nuclei (AGNs) drawn from the Sloan Digital Sky Survey is presented. The aim of this work is to provide estimations of the black hole (BH) mass for the sample galaxies from the dynamics of the broad-line region. For this purpose, a detailed spectroscopic analysis of the objects was done. UsingChavushyan, Vahram H. et al.
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12013 -
Excitation of emission lines by fluorescence and recombination in IC 418We compare calculated intensities of lines of C II, N I, N II, O I and O II with a published deep spectroscopic survey of IC 418. Our calculations use a self-consistent nebular model and a synthetic spectrum of the central star atmosphere to take into account line excitation by continuum fluorescence and electron recombination. We found that the NEscalante, V. et al.
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112012 -
Spatially resolved near-infrared spectroscopy of the massive star-forming region IRAS 19410+2336Aims: IRAS 19410+2336 is a young massive star forming region with an intense outflow activity. Outflows are frequently studied in the near-infrared (NIR) since the H2 emission in this wavelength range often traces the shocked molecular gas. However, the mechanisms behind the H2 emission detected in IRAS 19410+2336 have not been clarified yet. WeMartín-Hernández, N. L. et al.
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102008 -
A mid-infrared study of H II regions in the Magellanic Clouds: N88 A and N160 AAims: To show the importance of high-spatial resolution observations of H II regions when compared with observations obtained with larger apertures such as ISO, we present mid-infrared spectra of two Magellanic Cloud H II regions, N88 A and N160 A. Methods: We obtained mid-infrared (8-13 μm), long-slit spectra with TIMMI2 on the ESO 3.6 m telescopeMartín-Hernández, N. L. et al.
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102008 -
A spatial study of the mid-IR emission features in four Herbig Ae/Be starsContext: Infrared (IR) spectroscopy and imaging provide a prime tool to study the characteristics of polycyclic aromatic hydrocarbon (PAH) molecules and the mineralogy in regions of star formation. Herbig Ae/Be stars are known to have varying amounts of natal cloud material present in their vicinity. Aims: Our aim is to study the characteristics ofBoersma, C. et al.
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72009 -
New insights on Stephan's Quintet: exploring the shock in three dimensionsAims: We study the ionized gas emission from the large scale shock region of Stephan's Quintet (SQ). Methods: We carried out integral field unit (IFU) optical spectroscopy on three pointings in and near the SQ shock. We used Potsdam MultiAperture Spectrometer (PMAS) on the 3.5 m Calar Alto telescope to obtain measures of emission lines that provideIglesias-Páramo, J. et al.
Advertised on:
32012 -
The distance to the C component of I Zw 18 and its star formation history. A probabilistic approachAims: We analyzed the resolved stellar population of the C component of the extremely metal-poor dwarf galaxy I Zw18 in order to evaluate its distance and star formation history as accurately as possible. In particular, we aimed at answering the question of whether this stellar population is young. Methods: We developed a probabilistic approach toJamet, L. et al.
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12010 -
On emission-line spectra obtained from evolutionary synthesis models. II. Scale-relations and the estimation of mass dependencesAims: In this paper we study the influence of the ionizing cluster mass on the emission line spectrum of H ii regions in order to determine the influence of low mass clusters on the integrated emission line spectra of galaxies. Methods: For this purpose, we present a grid of photoionization models that covers metallicities from Z = 0.001 to Z = 0Villaverde, M. et al.
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72010 -
Modeling the ionizing spectra of H II regions: individual stars versus stellar ensemblesAims: We study how IMF sampling affects the ionizing flux and emission line spectra of low mass stellar clusters. Methods: We performed 2 × 106 Monte Carlo simulations of zero-age solar-metallicity stellar clusters covering the 20-106 M&sun; mass range. We study the distribution of cluster stellar masses, Mclus, ionizing fluxes, Q(H0), andVillaverde, M. et al.
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112010 -
Fluorescent Excitation of Balmer Lines in Gaseous Nebulae: Case DNonionizing stellar continua are a potential source of photons for continuum pumping in the hydrogen Lyman transitions. In the environments where these transitions are optically thick, de-excitation occurs through higher series lines. As a result, the emitted flux in the affected lines has a fluorescent contribution in addition to the usualLuridiana, V. et al.
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22009 -
Temperature Structure and Metallicity in H II RegionsThe metallicities implied by collisionally excited lines (CELs) of heavy elements in H II regions are systematically lower than those implied by recombination lines (RLs) by factors of ~2, introducing uncertainties of the same order in the metallicities inferred for the interstellar medium of any star-forming galaxy. Most explanations of thisRodríguez, Mónica et al.
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12010 -
Analysis of chemical abundances in planetary nebulae with [WC] central stars. I. Line intensities and physical conditionsContext. Planetary nebulae (PNe) around Wolf-Rayet [WR] central stars ([WR]PNe) constitute a particular photoionized nebula class that represents about 10% of the PNe with classified central stars. Aims: We analyse deep high-resolution spectrophotometric data of 12 [WR] PNe. This sample of [WR]PNe represents the most extensive analysed so far, atGarcía-Rojas, J. et al.
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22012 -
The ionized gas at the centre of IC 10: a possible localized chemical pollution by Wolf-Rayet starsWe present results from integral field spectroscopy with the Potsdam Multi-Aperture Spectrograph at the 3.5-m telescope at Calar Alto Observatory of the intense star-forming region [HL90] 111 at the centre of the starburst galaxy IC 10. We have obtained maps with a spatial sampling of 1 × 1 arcsec2= 3.9× 3.9 pc2 of different emission lines andLópez-Sánchez, Á. R. et al.
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32011 -
The intriguing H I gas in NGC 5253: an infall of a diffuse, low-metallicity H I cloud?We present new, deep H I line and 20-cm radio-continuum data of the very puzzling blue compact dwarf galaxy NGC 5253, obtained with the Australia Telescope Compact Array as part of the 'Local Volume H I Survey' (LVHIS). Our low-resolution H I maps show, for the first time, the disturbed H I morphology that NGC 5253 possesses, including tailsLópez-Sánchez, Á. R. et al.
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12012 -
Small-spatial-scale variations of nebular properties and the abundance discrepancy in three Galactic HII regionsWe present the results of long-slit spectroscopy in several slit positions that cover different morphological structures of the central parts of three bright Galactic HII regions: M8, M17 and NGC 7635. We study the spatial distributions of a large number of nebular parameters, such as the extinction coefficient, line fluxes, physical conditions andMesa-Delgado, A. et al.
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72010 -
Small-Scale Behavior of the Physical Conditions and the Abundance Discrepancy in the Orion NebulaWe present the results of long-slit spectroscopy, in several positions, of the Orion Nebula. Our goal is to study the spatial distributions of a large number of nebular quantities, including line fluxes, physical conditions, and ionic abundances, at a spatial resolution of about 1". In particular, we have compared the O++ abundance determined fromMesa-Delgado, Adal et al.
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32008 -
Properties of the ionized gas in HH202 - I. Results from integral field spectroscopy with PMASWe present results from integral field spectroscopy with the Potsdam Multi-Aperture Spectrograph of the head of the Herbig-Haro (HH) object HH202 with a spatial sampling of 1 × 1arcsec2. We have obtained maps of different emission lines, physical conditions - such as electron temperature and density - and ionic abundances from recombination andMesa-Delgado, A. et al.
Advertised on:
42009
