Belén Mari - Academia.edu (original) (raw)
Papers by Belén Mari
Here we present the spatially resolved study of six Galactic planetary nebulae (PNe), namely IC 4... more Here we present the spatially resolved study of six Galactic planetary nebulae (PNe), namely IC 4593, Hen 2-186, Hen 2-429, NGC 3918, NGC 6543 and NGC 6905, from intermediate-resolution spectra of the 2.5 m Isaac Newton Telescope and the 1.54 m Danish telescope. The physical conditions (electron densities, N , and temperatures, T), chemical compositions and dominant excitation mechanisms for the different regions of these objects are derived, in an attempt to go deeper on the knowledge of the low-ionization structures (LISs) hosted by these PNe. We reinforce the previous conclusions that LISs are characterized by lower (or at most equal) N than their associated rims and shells. As for the T , we point out a possible different trend between the N and O diagnostics. T [N ] does not show significant variations throughout the nebular components, whereas T [O ] appears to be slightly higher for LISs. The much larger uncertainties associated with the T [O ] of LISs do not allow robust conclusions. Moreover, the chemical abundances show no variation from one to another PN components, not even contrasting LISs with rims and shells, as also found in a number of other works. By discussing the ionization photon flux due to shocks and stellar radiation, we explore the possible mechanisms responsible for the excitation of LISs. We argue that the presence of shocks in LISs is not negligible, although there is a strong dependence on the orientation of the host PNe and LISs.
VizieR Online Data Catalog, Jun 1, 2020
Astronomy & Astrophysics, 2020
Planetary nebulae represent a potential late stage of stellar evolution, however, their central s... more Planetary nebulae represent a potential late stage of stellar evolution, however, their central stars (CSPNe) are relatively faint and, therefore, pertinent information is available for merely < 20% of the Galactic sample. Consequently, the literature was surveyed to construct a new catalogue of 620 CSPNe featuring important spectral classifications and information. The catalogue supersedes the existing iteration by 25% and includes physical parameters such as luminosity, surface gravity, temperature, magnitude estimates, and references for published spectra. The marked statistical improvement enabled the following pertinent conclusions to be determined: the H-rich/H-poor ratio is 2:1, there is a deficiency of CSPNe with types [WC 5-6], and nearly 80% of binary central stars belong to the H-rich group. The last finding suggests that evolutionary scenarios leading to the formation of binary central stars interfere with the conditions required for the formation of H-poor CSPN. Appr...
En este trabajo presentamos una evaluación de algunos parámetros que intervienen en la reducción ... more En este trabajo presentamos una evaluación de algunos parámetros que intervienen en la reducción y calibración en flujo de espectros de CASLEO obtenidos con el espectrógrafo REOSC/DS, con el objetivo de cuantificar las incertezas involucradas y así mejorar nuestros estudios en objetos con líneas de emisión. Para esto se analizaron 21 espectros de una nebulosa planetaria (NP) estándar de flujo, durante cinco noches consecutivas. Con estos datos, estimamos la incerteza en flujo que puede esperarse en CASLEO en objetos que contengan líneas de emisión. Paralelamente, a partir de los espectros de las estrellas estándares, estudiamos las distintas opciones de corrección por flat, para determinar el impacto que esta corrección causa sobre los espectros reducidos. Finalmente, se evalúo la medida de la calidad de la noche y el error en la medición en flujo. Nuestros resultados muestran que para la región roja de los espectros, los errores son del ∼ 4 % y se incrementan hacia la región del azul. Además, verificamos que la corrección por flat mejora los resultados y que los errores en la medición de flujos no son despreciables.In this paper, we present an evaluation of some parameters involved in the reduction and flux calibration for CASLEO REOSC/DS spectra, with the aim of quantify the uncertainties involved and so improve our studies on line emission objetcs. For this purpose, we observed a flux standard planetary nebula (PN) during five consecutive nights and analyzed 21 spectra. With this data we estimated the flux uncertainty that can be expected in CASLEO in objects that contain emission lines. From the spectra of the standard stars, we studied the different possible option for the flat correction to determine the impact of this correction on the reduced spectra. Finally, the quality of the night and the error in the flux measurement of the lines were evaluated. Our results show that for the red region of the spectrum the errors are ∼ 4% and increasing towards the blue region. We also verified that the flat correction is necessary and that the flux measurement errors are not negligible.Fil: Mari, María Belén. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Gaspar, Gaia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; ArgentinaFil: Weidmann, Walter Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentin
“Derecho al cielo” is a teaching and learning project about astronomy, carried out by an interdis... more “Derecho al cielo” is a teaching and learning project about astronomy, carried out by an interdisciplinary group made up of professionals related to the Universidad Nacional de Cordoba (UNC), together with young people in confinement context. We organize workshops which aim at promoting the connection with the sky and at encouraging its observation as a form of interaction with elements outside the institution. Thus, we attempt to create a different learning environment, in which the youth’s daily knowledge about astronomy could be appreciated. Currently, we develop activities in Complejo Esperanza (CE) and Centro Socioeducativo para Adolescentes Mujeres (CeSAM), both in Cordoba, Argentina. In this article, we would like to share our experience and outcomes, some questions and ideas emerging from the development of this project, with the goal of fostering future activities in confinement context.
In addition to large-scale structures, planetary nebulae (PNe) show small-scale structures that e... more In addition to large-scale structures, planetary nebulae (PNe) show small-scale structures that emit mainly in low-ionization species such as [N ii], [S ii], [O ii], and [O i], known as LISs. Here, we present the analysis of optical long-slit spectra, for three slit positions, of the PN IC 4593, which possesses a pair of knots and an isolated low-ionization knot. The motivation for this work is the need to characterize LISs completely to evaluate their impact on the PNe studies. These data allow us to derive the physical properties and ionization state for each morphological component of the nebula, including its pair of knots and individual knot. Due to the large uncertainties in the [S ii] derived electron densities, we cannot confirm any contrast between the LISs’ electron densities and the surrounding nebula, found in numerous other LISs. Though the lack of spatially-resolved physical parameters in the literature prevents further comparisons, in general, our results derived for ...
Galaxies
In addition to large-scale structures, planetary nebulae (PNe) show small-scale structures that e... more In addition to large-scale structures, planetary nebulae (PNe) show small-scale structures that emit mainly in low-ionization species such as [N ii], [S ii], [O ii], and [O i], known as LISs. Here, we present the analysis of optical long-slit spectra, for three slit positions, of the PN IC 4593, which possesses a pair of knots and an isolated low-ionization knot. The motivation for this work is the need to characterize LISs completely to evaluate their impact on the PNe studies. These data allow us to derive the physical properties and ionization state for each morphological component of the nebula, including its pair of knots and individual knot. Due to the large uncertainties in the [S ii] derived electron densities, we cannot confirm any contrast between the LISs’ electron densities and the surrounding nebula, found in numerous other LISs. Though the lack of spatially-resolved physical parameters in the literature prevents further comparisons, in general, our results derived for ...
Here we present the spatially resolved study of six Galactic planetary nebulae (PNe), namely IC 4... more Here we present the spatially resolved study of six Galactic planetary nebulae (PNe), namely IC 4593, Hen 2-186, Hen 2-429, NGC 3918, NGC 6543 and NGC 6905, from intermediate-resolution spectra of the 2.5 m Isaac Newton Telescope and the 1.54 m Danish telescope. The physical conditions (electron densities, N , and temperatures, T), chemical compositions and dominant excitation mechanisms for the different regions of these objects are derived, in an attempt to go deeper on the knowledge of the low-ionization structures (LISs) hosted by these PNe. We reinforce the previous conclusions that LISs are characterized by lower (or at most equal) N than their associated rims and shells. As for the T , we point out a possible different trend between the N and O diagnostics. T [N ] does not show significant variations throughout the nebular components, whereas T [O ] appears to be slightly higher for LISs. The much larger uncertainties associated with the T [O ] of LISs do not allow robust conclusions. Moreover, the chemical abundances show no variation from one to another PN components, not even contrasting LISs with rims and shells, as also found in a number of other works. By discussing the ionization photon flux due to shocks and stellar radiation, we explore the possible mechanisms responsible for the excitation of LISs. We argue that the presence of shocks in LISs is not negligible, although there is a strong dependence on the orientation of the host PNe and LISs.
VizieR Online Data Catalog, Jun 1, 2020
Astronomy & Astrophysics, 2020
Planetary nebulae represent a potential late stage of stellar evolution, however, their central s... more Planetary nebulae represent a potential late stage of stellar evolution, however, their central stars (CSPNe) are relatively faint and, therefore, pertinent information is available for merely < 20% of the Galactic sample. Consequently, the literature was surveyed to construct a new catalogue of 620 CSPNe featuring important spectral classifications and information. The catalogue supersedes the existing iteration by 25% and includes physical parameters such as luminosity, surface gravity, temperature, magnitude estimates, and references for published spectra. The marked statistical improvement enabled the following pertinent conclusions to be determined: the H-rich/H-poor ratio is 2:1, there is a deficiency of CSPNe with types [WC 5-6], and nearly 80% of binary central stars belong to the H-rich group. The last finding suggests that evolutionary scenarios leading to the formation of binary central stars interfere with the conditions required for the formation of H-poor CSPN. Appr...
En este trabajo presentamos una evaluación de algunos parámetros que intervienen en la reducción ... more En este trabajo presentamos una evaluación de algunos parámetros que intervienen en la reducción y calibración en flujo de espectros de CASLEO obtenidos con el espectrógrafo REOSC/DS, con el objetivo de cuantificar las incertezas involucradas y así mejorar nuestros estudios en objetos con líneas de emisión. Para esto se analizaron 21 espectros de una nebulosa planetaria (NP) estándar de flujo, durante cinco noches consecutivas. Con estos datos, estimamos la incerteza en flujo que puede esperarse en CASLEO en objetos que contengan líneas de emisión. Paralelamente, a partir de los espectros de las estrellas estándares, estudiamos las distintas opciones de corrección por flat, para determinar el impacto que esta corrección causa sobre los espectros reducidos. Finalmente, se evalúo la medida de la calidad de la noche y el error en la medición en flujo. Nuestros resultados muestran que para la región roja de los espectros, los errores son del ∼ 4 % y se incrementan hacia la región del azul. Además, verificamos que la corrección por flat mejora los resultados y que los errores en la medición de flujos no son despreciables.In this paper, we present an evaluation of some parameters involved in the reduction and flux calibration for CASLEO REOSC/DS spectra, with the aim of quantify the uncertainties involved and so improve our studies on line emission objetcs. For this purpose, we observed a flux standard planetary nebula (PN) during five consecutive nights and analyzed 21 spectra. With this data we estimated the flux uncertainty that can be expected in CASLEO in objects that contain emission lines. From the spectra of the standard stars, we studied the different possible option for the flat correction to determine the impact of this correction on the reduced spectra. Finally, the quality of the night and the error in the flux measurement of the lines were evaluated. Our results show that for the red region of the spectrum the errors are ∼ 4% and increasing towards the blue region. We also verified that the flat correction is necessary and that the flux measurement errors are not negligible.Fil: Mari, María Belén. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Gaspar, Gaia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; ArgentinaFil: Weidmann, Walter Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentin
“Derecho al cielo” is a teaching and learning project about astronomy, carried out by an interdis... more “Derecho al cielo” is a teaching and learning project about astronomy, carried out by an interdisciplinary group made up of professionals related to the Universidad Nacional de Cordoba (UNC), together with young people in confinement context. We organize workshops which aim at promoting the connection with the sky and at encouraging its observation as a form of interaction with elements outside the institution. Thus, we attempt to create a different learning environment, in which the youth’s daily knowledge about astronomy could be appreciated. Currently, we develop activities in Complejo Esperanza (CE) and Centro Socioeducativo para Adolescentes Mujeres (CeSAM), both in Cordoba, Argentina. In this article, we would like to share our experience and outcomes, some questions and ideas emerging from the development of this project, with the goal of fostering future activities in confinement context.
In addition to large-scale structures, planetary nebulae (PNe) show small-scale structures that e... more In addition to large-scale structures, planetary nebulae (PNe) show small-scale structures that emit mainly in low-ionization species such as [N ii], [S ii], [O ii], and [O i], known as LISs. Here, we present the analysis of optical long-slit spectra, for three slit positions, of the PN IC 4593, which possesses a pair of knots and an isolated low-ionization knot. The motivation for this work is the need to characterize LISs completely to evaluate their impact on the PNe studies. These data allow us to derive the physical properties and ionization state for each morphological component of the nebula, including its pair of knots and individual knot. Due to the large uncertainties in the [S ii] derived electron densities, we cannot confirm any contrast between the LISs’ electron densities and the surrounding nebula, found in numerous other LISs. Though the lack of spatially-resolved physical parameters in the literature prevents further comparisons, in general, our results derived for ...
Galaxies
In addition to large-scale structures, planetary nebulae (PNe) show small-scale structures that e... more In addition to large-scale structures, planetary nebulae (PNe) show small-scale structures that emit mainly in low-ionization species such as [N ii], [S ii], [O ii], and [O i], known as LISs. Here, we present the analysis of optical long-slit spectra, for three slit positions, of the PN IC 4593, which possesses a pair of knots and an isolated low-ionization knot. The motivation for this work is the need to characterize LISs completely to evaluate their impact on the PNe studies. These data allow us to derive the physical properties and ionization state for each morphological component of the nebula, including its pair of knots and individual knot. Due to the large uncertainties in the [S ii] derived electron densities, we cannot confirm any contrast between the LISs’ electron densities and the surrounding nebula, found in numerous other LISs. Though the lack of spatially-resolved physical parameters in the literature prevents further comparisons, in general, our results derived for ...