Ignacio Negueruela - Academia.edu (original) (raw)
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Papers by Ignacio Negueruela
and other research outputs The identification of the optical/IR counterpart of the 15.8-s transie... more and other research outputs The identification of the optical/IR counterpart of the 15.8-s transient X-ray pulsar XTE J1946+274 Journal Article
Astronomy & Astrophysics, 2018
Context.The IACOB and OWN surveys are two ambitious, complementary observational projects which h... more Context.The IACOB and OWN surveys are two ambitious, complementary observational projects which have made available a large multi-epoch spectroscopic database of optical high resolution spectra of Galactic massive O-type stars.Aims.Our aim is to study the full sample of (more than 350) O stars surveyed by the IACOB and OWN projects. As a first step towards this aim, we have performed the quantitative spectroscopic analysis of a subsample of 128 stars included in the modern grid of O-type standards for spectral classification. The sample comprises stars with spectral types in the range O3–O9.7 and covers all luminosity classes.Methods.We used the semi-automatizedIACOB-BROADandIACOB-GBAT/FASTWINDtools to determine the complete set of spectroscopic parameters that can be obtained from the optical spectrum of O-type stars. A quality flag was assigned to the outcome of theIACOB-GBAT/FASTWINDanalysis for each star, based on a visual evaluation of how the synthetic spectrum of the best fit...
Monthly Notices of the Royal Astronomical Society, 2017
Astronomy & Astrophysics, 2014
Research Notes of the AAS, 2020
Monthly Notices of the Royal Astronomical Society, 2018
Astronomy & Astrophysics, 2018
Context. NGC 3105 is a young open cluster hosting blue, yellow, and red supergiants. This rare co... more Context. NGC 3105 is a young open cluster hosting blue, yellow, and red supergiants. This rare combination makes it an excellent laboratory for constraining evolutionary models of high-mass stars. It has been poorly studied, and the fundamental parameters such as its age or distance are not well defined.Aims. We intend to characterise in an accurate way the cluster and its evolved stars, for which we derive for the first time atmospheric parameters and chemical abundances.Methods. We performed a complete analysis combiningUBVRphotometry with spectroscopy. We obtained spectra with classification purposes for 14 blue stars and high-resolution spectroscopy for an in-depth analysis of the six other evolved stars.Results. We identify 126 B-type likely members within a radius of 2.7 ± 0.6 arcmin, which implies an initial mass,Mcl≈ 4100M⊙. We find a distance of 7.2 ± 0.7 kpc for NGC 3105, placing it atRGC= 10.0 ± 1.2 kpc. Isochrone fitting supports an age of 28 ± 6 Ma, implying masses arou...
Monthly Notices of the Royal Astronomical Society, 2018
Proceedings of the International Astronomical Union, 2015
Very recently, a number of obscured massive open clusters have been identified in the Milky Way. ... more Very recently, a number of obscured massive open clusters have been identified in the Milky Way. A very significant fraction of them lie either close to the base of the Scutum Arm or towards Galactic longitude of 350°. We are studying these clusters and their neighbourhoods, finding very good evidence for a major starburst region close to the near tip of the Galactic Long Bar.
EAS Publications Series, 2013
We are using a sample of more than 50 standard very late-type stars, taken from Isaac Newton Tele... more We are using a sample of more than 50 standard very late-type stars, taken from Isaac Newton Telescope at R ~ 9000 in the 8100–9100 A range, in order to develop criteria for spectral and luminosity classification of very late-type stars in the Gaia region. In this article, we brief in a few pages the main challenges on this issue, as well as the literature about it, and we present some preliminary results.
The authors present X-ray observations of the Be/X-ray transient 4U 0115+63 taken with the OSSE i... more The authors present X-ray observations of the Be/X-ray transient 4U 0115+63 taken with the OSSE instrument on board of the Compton Gamma Ray Observatory which show the occurrence of a flare around May 1994. They have studied the evolution of the continuum spectrum and searched for possible changes in the pulse period during the flaring event. They also present long-term
The Astrophysical Journal, 2006
Monthly Notices of the Royal Astronomical Society, 2008
Monthly Notices of the Royal Astronomical Society, 2003
![Research paper thumbnail of Spectroscopic observations of the candidate sgB[e]/X-ray binary CI�Camelopardalis](https://attachments.academia-assets.com/95025611/thumbnails/1.jpg)
](Astronomy and Astrophysics, 2002
Astronomy & Astrophysics, 2002
Astronomy and Astrophysics, 2002
Astronomy & Astrophysics, 2012
and other research outputs The identification of the optical/IR counterpart of the 15.8-s transie... more and other research outputs The identification of the optical/IR counterpart of the 15.8-s transient X-ray pulsar XTE J1946+274 Journal Article
Astronomy & Astrophysics, 2018
Context.The IACOB and OWN surveys are two ambitious, complementary observational projects which h... more Context.The IACOB and OWN surveys are two ambitious, complementary observational projects which have made available a large multi-epoch spectroscopic database of optical high resolution spectra of Galactic massive O-type stars.Aims.Our aim is to study the full sample of (more than 350) O stars surveyed by the IACOB and OWN projects. As a first step towards this aim, we have performed the quantitative spectroscopic analysis of a subsample of 128 stars included in the modern grid of O-type standards for spectral classification. The sample comprises stars with spectral types in the range O3–O9.7 and covers all luminosity classes.Methods.We used the semi-automatizedIACOB-BROADandIACOB-GBAT/FASTWINDtools to determine the complete set of spectroscopic parameters that can be obtained from the optical spectrum of O-type stars. A quality flag was assigned to the outcome of theIACOB-GBAT/FASTWINDanalysis for each star, based on a visual evaluation of how the synthetic spectrum of the best fit...
Monthly Notices of the Royal Astronomical Society, 2017
Astronomy & Astrophysics, 2014
Research Notes of the AAS, 2020
Monthly Notices of the Royal Astronomical Society, 2018
Astronomy & Astrophysics, 2018
Context. NGC 3105 is a young open cluster hosting blue, yellow, and red supergiants. This rare co... more Context. NGC 3105 is a young open cluster hosting blue, yellow, and red supergiants. This rare combination makes it an excellent laboratory for constraining evolutionary models of high-mass stars. It has been poorly studied, and the fundamental parameters such as its age or distance are not well defined.Aims. We intend to characterise in an accurate way the cluster and its evolved stars, for which we derive for the first time atmospheric parameters and chemical abundances.Methods. We performed a complete analysis combiningUBVRphotometry with spectroscopy. We obtained spectra with classification purposes for 14 blue stars and high-resolution spectroscopy for an in-depth analysis of the six other evolved stars.Results. We identify 126 B-type likely members within a radius of 2.7 ± 0.6 arcmin, which implies an initial mass,Mcl≈ 4100M⊙. We find a distance of 7.2 ± 0.7 kpc for NGC 3105, placing it atRGC= 10.0 ± 1.2 kpc. Isochrone fitting supports an age of 28 ± 6 Ma, implying masses arou...
Monthly Notices of the Royal Astronomical Society, 2018
Proceedings of the International Astronomical Union, 2015
Very recently, a number of obscured massive open clusters have been identified in the Milky Way. ... more Very recently, a number of obscured massive open clusters have been identified in the Milky Way. A very significant fraction of them lie either close to the base of the Scutum Arm or towards Galactic longitude of 350°. We are studying these clusters and their neighbourhoods, finding very good evidence for a major starburst region close to the near tip of the Galactic Long Bar.
EAS Publications Series, 2013
We are using a sample of more than 50 standard very late-type stars, taken from Isaac Newton Tele... more We are using a sample of more than 50 standard very late-type stars, taken from Isaac Newton Telescope at R ~ 9000 in the 8100–9100 A range, in order to develop criteria for spectral and luminosity classification of very late-type stars in the Gaia region. In this article, we brief in a few pages the main challenges on this issue, as well as the literature about it, and we present some preliminary results.
The authors present X-ray observations of the Be/X-ray transient 4U 0115+63 taken with the OSSE i... more The authors present X-ray observations of the Be/X-ray transient 4U 0115+63 taken with the OSSE instrument on board of the Compton Gamma Ray Observatory which show the occurrence of a flare around May 1994. They have studied the evolution of the continuum spectrum and searched for possible changes in the pulse period during the flaring event. They also present long-term
The Astrophysical Journal, 2006
Monthly Notices of the Royal Astronomical Society, 2008
Monthly Notices of the Royal Astronomical Society, 2003
Astronomy and Astrophysics, 2002
Astronomy & Astrophysics, 2002
Astronomy and Astrophysics, 2002
Astronomy & Astrophysics, 2012