96 citations · 888 across the 50 of their papers we have counts for
29 papers · 1 filter
The DESIRED temperature-metallicity relations in star-forming regions: probing the Galactic radial and azimuthal metallicity distributions
I. Rafael Martínez-Hernández, J. Eduardo Méndez-Delgado, César Esteban +17
We analyse a sample of 225 star-forming regions from the DESIRED-E project, each with simultaneous determinations of the electron temperature from ionized nitrogen and oxygen, $T_{…
Chlorine abundances in star-forming regions of the local Universe
M. Orte-García, C. Esteban, J. E. Méndez-Delgado +4
Aims. We study the behaviour of Cl abundance and its ratios with respect to O, S and Ar abundances in a sample of more than 200 spectra of Galactic and extragalactic H ii regions a…
Alpha-element abundance patterns in star-forming regions of the local Universe
C. Esteban, J. E. Méndez-Delgado, J. García-Rojas +6
(Abridged) We reassess the alpha-element abundance ratios (Ne/O, S/O, Ar/O) with respect to metallicity in ~1000 spectra of Galactic and extragalactic HII regions and star-forming…
On the chlorine abundance in H II regions
Maialen Orte-García, César Esteban, José Eduardo Méndez-Delgado +1
Chlorine (Cl) is a chemical element of the group of the halogens and is between the 17th and the 20th most abundant elements in the Solar System. It is thought to be produced from…
Generalized ([OIII])-(HeI) Discrepancies in Ionized Nebulae: Possible Evidence of Case B Deviations and Temperature Inhomogeneities
J. E. Méndez-Delgado, E. D. Skillman, E. Aver +11
The physics of recombination lines (RLs) in the HeI singlet system is expected to be relatively simple, supported by accurate atomic models. We examine the intensities of HeI singl…
Gas-phase Fe/O and Fe/N abundances in Star-Forming Regions. Relations between nucleosynthesis, metallicity and dust
J. E. Méndez-Delgado, K. Kreckel, C. Esteban +10
In stars, metallicity is usually traced using Fe, while in nebulae, O serves as the preferred proxy. Both elements have different nucleosynthetic origins and are not directly compa…
Excitation mechanisms of C II optical permitted lines in ionized nebulae
E. Reyes-Rodríguez, J. E. Méndez-Delgado, J. García-Rojas +4
Context. Carbon is the fourth most abundant element in the universe and its distribution is critical to understanding stellar evolution and nucleosynthesis. In optical studies of i…
The abundance discrepancy in ionized nebulae: which are the correct abundances?
José Eduardo Méndez-Delgado, Jorge García-Rojas
Ionized nebulae are key to understanding the chemical composition and evolution of the Universe. Among these nebulae, H~{\sc ii} regions and planetary nebulae are particularly impo…
Temperature inhomogeneities in Mrk71 can not be discarded
J. Eduardo Méndez-Delgado, César Esteban, Jorge García-Rojas +2
In a very recent work, [1] claim that the scenario of temperature inhomogeneities proposed by [2] ( > 0) is not able to explain the O/H abundance discrepancy obser…
On the computation of interstellar extinction in photoionized nebulae
Christophe Morisset, Romano L. M. Corradi, Jorge García-Rojas +5
Ueta & Otsuka (2021) proposed a method, named as the "Proper Plasma Analysis Practice", to analyze spectroscopic data of ionized nebulae. The method is based on a coherent and simu…
The planetary nebula NGC 6153 through the eyes of MUSE
V. Gómez-Llanos, J. García-Rojas, C. Morisset +7
In this contribution, we present the results of a study on the high abundance discrepancy factor (ADF 10) planetary nebula (PN) NGC 6153 with MUSE. We have constructed flux…
The homogeneity of chemical abundances in H II regions of the Magellanic Clouds
G. Domínguez-Guzmán, M. Rodríguez, J. García-Rojas +3
We use very deep spectra obtained with the Ultraviolet-Visual Echelle Spectrograph at the Very Large Telescope to derive physical conditions and chemical abundances of four H II re…
Photoionized Herbig-Haro objects in the Orion Nebula through deep high-spectral resolution spectroscopy III: HH514
J. E. Méndez-Delgado, C. Esteban, J. García-Rojas +2
We analyze the physical conditions and chemical composition of the photoionized Herbig-Haro object HH~514, which emerges from the proplyd 170-337 in the core of the Orion Nebula. W…
Gradients of chemical abundances in the Milky Way from HII regions: distances derived from Gaia EDR3 parallaxes and temperature inhomogeneities
J. E. Méndez-Delgado, A. Amayo, K. Z. Arellano-Córdova +4
We present a reassessment of the radial abundance gradients of He, C, N, O, Ne, S, Cl, and Ar in the Milky Way using the deep optical spectra of 42 HII regions presented in Arellan…
On the most luminous planetary nebulae of M31
Rebeca Galera-Rosillo, Antonio Mampaso, Romano L. M. Corradi +6
To study the progenitors of PNe at the tip of the Planetary Nebula Luminosity Function (PNLF), we obtained the deepest existing spectra of a sample of PNe in the galaxy M31. Precis…
On the radial abundance gradients of nitrogen and oxygen in the inner Galactic disc
Karla. Z. Arellano-Córdova, César Esteban, Jorge García-Rojas +1
We present optical spectra of nine Galactic H II regions observed with the 10.4 m Gran Telescopio Canarias telescope and located at Galactocentric distances (RG) from 4 to 8 kpc. T…
A study of extragalactic planetary nebulae populations based on spectroscopy. I. Data compilation and first findings
Gloria Delgado-Inglada, Jorge García-Rojas, Grazyna Stasińska +1
We compile published spectroscopic data and [O III] magnitudes of almost 500 extragalactic planetary nebulae (PNe) in 13 galaxies of various masses and morphological types. This is…
The Galactic radial abundance gradients of C, N, O, Ne, S, Cl and Ar from deep spectra of H II regions
Karla. Z. Arellano-Córdova, César Esteban, Jorge García-Rojas +1
We present a reassessment of the radial abundance gradients of C, N, O, Ne, S, Cl and Ar in the Milky Way using deep spectra of 33 H II regions gathered from the literature, coveri…
Ionization correction factors for sodium, potassium, and calcium in planetary nebulae
Alexia Amayo, Gloria Delgado-Inglada, Jorge García-Rojas
We use a large grid of photoionization models that are representative of observed planetary nebulae (PNe) to derive ionization correction factors (ICFs) for sodium, potassium, and…
Chemical abundances and temperature structure of H II regions
G. Domínguez-Guzmán, M. Rodríguez, C. Esteban +1
We use a sample of 37 H II regions with high quality spectra to study the behavior of the relative abundances of several elements as a function of metallicity. The sample includes…
Chemistry in the dIrr galaxy Leo A
Francisco Ruiz-Escobedo, Miriam Peña, Liliana Hernández-Martínez +1
We present chemical abundance determinations of two H II regions in the dIrr galaxy Leo A, from GTC OSIRIS long-slit spectra. Both H II regions are of low excitation and seem to be…
Carbon and oxygen in HII regions of the Magellanic Clouds: abundance discrepancy and chemical evolution
L. Toribio San Cipriano, G. Domínguez-Guzmán, C. Esteban +5
We present C and O abundances in the Magellanic Clouds derived from deep spectra of HII regions. The data have been taken with the Ultraviolet-Visual Echelle Spectrograph at the 8.…
The abundance discrepancy in H II regions
C. Esteban, L. Toribio San Cipriano, J. García-Rojas
In this paper we discuss some results concerning the abundance discrepancy problem in the context of H II regions. We discuss the behavior of the abundance discrepancy factor (ADF)…
Carbon and oxygen abundance gradients in NGC300 and M33 from optical recombination lines
L. Toribio San Cipriano, J. García-Rojas, C. Esteban +2
We present deep spectrophotometry of several Hii regions in the nearby low-mass spiral galaxies NGC 300 and M33. The data have been taken with UVES and OSIRIS spectrographs attache…