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We observed a B0IVe star, HD 51452, with the high-precision, high-cadence photometric CoRoT satellite and high-resolution, ground-based HARPS and SOPHIE spectrographs to study its pulsations in great detail. We also used the lower resolution spectra available in the BeSS database. Thanks to CoRoT data, we have detected a new kind of pulsations in HD 51452, which are stochastically excited gravito-inertial modes, probably due to its very rapid rotation. These modes are probably also present in other rapidly rotating hot Be stars.

 ASTRONOMY & ASTROPHYSICS, Volume 546, id.A47, 14 pp.

We observed a B0IVe star, HD 51452, with the high-precision, high-cadence photometric CoRoT satellite and high-resolution, ground-based HARPS and SOPHIE spectrographs to study its pulsations in great detail. We also used the lower resolution spectra available in the BeSS database. Thanks to CoRoT data, we have detected a new kind of pulsations in HD 51452, which are stochastically excited gravito-inertial modes, probably due to its very rapid rotation. These modes are probably also present in other rapidly rotating hot Be stars.

+info: http://adsabs.harvard.edu/abs/2012A%26A...546A..47N

Because of the development of large-format, wide-field cameras, microlensing surveys will span the full range of significance levels including planetary signals too small to be distinguished from the noise. At present, we do not understand where the threshold is for detecting planets. MOA-2011-BLG-293Lb is the first planet to be published from the new surveys.This event suggests a means to probe the detection threshold, by analyzing a large sample of events like MOA-2011-BLG-293.

THE ASTROPHYSICAL JOURNAL, Volume 755, Issue 2, Article id. 102, 14 pp. (2012).

Because of the development of large-format, wide-field cameras, microlensing surveys  will span the full range of significance levels including planetary signals too small to be distinguished from the noise. At present, we do not understand where the threshold is for detecting planets. MOA-2011-BLG-293Lb is the first planet to be published from the new surveys.This event suggests a means to probe the detection threshold, by analyzing a large sample of events like MOA-2011-BLG-293.

+info: http://adsabs.harvard.edu/abs/2012ApJ...755..102Y

Microlensing detections of cool planets are important for the construction of an unbiased sample to estimate the frequency of planets beyond the snow line, which is where giant planets are thought to form according to the core accretion theory of planet formation. In this paper, we report the discovery of a giant planet detected from the analysis of the light curve of a high-magnification microlensing event MOA 2010-BLG-477.

THE ASTROPHYSICAL JOURNAL, Volume 754, Issue 1, Article id. 73, 17 pp. (2012).

Microlensing detections of cool planets are important for the construction of an unbiased sample to estimate the frequency of planets beyond the snow line, which is where giant planets are thought to form according to the core accretion theory of planet formation. In this paper, we report the discovery of a giant planet detected from the analysis of the light curve of a high-magnification microlensing event MOA 2010-BLG-477.

+info: http://adsabs.harvard.edu/abs/2012ApJ...754...73B

BAO are imprinted in the density field by acoustic waves travelling in the plasma of the early universe. Their fixed scale can be used as a standard ruler to study the geometry of the universe. The BAO have been previously detected using correlation functions and power spectra of the galaxy distribution. We present a new method to detect the real-space structures associated with BAO. These baryon acoustic structures are spherical shells of relatively small density contrast, surrounding high density central regions.

ASTRONOMY & ASTROPHYSICS, Volume 542, id.A34, 11 pp.

BAO are imprinted in the density field by acoustic waves travelling in the plasma of the early universe. Their fixed scale can be used as a standard ruler to study the geometry of the universe. The BAO have been previously detected using correlation functions and power spectra of the galaxy distribution. We present a new method to detect the real-space structures associated with BAO. These baryon acoustic structures are spherical shells of relatively small density contrast, surrounding high density central regions.

+info: http://adsabs.harvard.edu/abs/2012A%26A...542A..34A

We study the relations between the multimodality of galaxy clusters drawn from the SDSS DR8 and the environment where they reside. As cluster environment we consider the global luminosity density field, supercluster membership, and supercluster.

 ASTRONOMY & ASTROPHYSICS, Volume 542, id.A36, 19 pp.

We study the relations between the multimodality of galaxy clusters drawn from the SDSS DR8 and the environment where they reside. As cluster environment we consider the global luminosity density field, supercluster membership, and supercluster.

+info: http://adsabs.harvard.edu/abs/2012A%26A...542A..36E

Our goal is to characterize the ability of the Advanced Large, Homogeneous Area Medium-Band Redshift Astronomical (ALHAMBRA) survey in assigning accurate photo-z's to broad-line AGN (BLAGN) and quasi-stellar objects (QSOs) based on their ALHAMBRA very-low-resolution optical-near-infrared (NIR) spectroscopy. This will serve as a benchmark for any future compilation of ALHAMBRA selected QSOs and the basis for the statistical analysis required to derive luminosity functions up to z ~ 5.

ASTRONOMY & ASTROPHYSICS, Volume 542, id.A20, 17 pp.

Our goal is to characterize the ability of the Advanced Large, Homogeneous Area Medium-Band Redshift Astronomical (ALHAMBRA) survey in assigning accurate photo-z's to broad-line AGN (BLAGN) and quasi-stellar objects (QSOs) based on their ALHAMBRA very-low-resolution optical-near-infrared (NIR) spectroscopy. This will serve as a benchmark for any future compilation of ALHAMBRA selected QSOs and the basis for the statistical analysis required to derive luminosity functions up to z ~ 5.

+info: http://adsabs.harvard.edu/abs/2012A%26A...542A..20M

Using microlensing measurements for a sample of 27 image pairs of 19 lensed quasars we determine a maximum likelihood estimate for the accretion disk size of an average quasar.

THE ASTROPHYSICAL JOURNAL, Volume 751, Issue 2, article id. 106, 6 pp. (2012).

Using microlensing measurements for a sample of 27 image pairs of 19 lensed quasars we determine a maximum likelihood estimate for the accretion disk size of an average quasar.

+info: http://adsabs.harvard.edu/abs/2012ApJ...751..106J

We present the analysis of the light curves of nine high-magnification single-lens gravitational microlensing events with lenses passing over source stars, including OGLE-2004-BLG-254, MOA-2007-BLG-176, MOA-2007-BLG-233/OGLE-2007-BLG-302, MOA-2009-BLG-174, MOA-2010-BLG-436, MOA-2011-BLG-093, MOA-2011-BLG-274, OGLE-2011-BLG-0990/MOA-2011-BLG-300, and OGLE-2011-BLG-1101/MOA-2011-BLG-325.

THE ASTROPHYSICAL JOURNAL, Volume 751, Issue 1, Article id. 41, 14 pp. (2012).

We present the analysis of the light curves of nine high-magnification single-lens gravitational microlensing events with lenses passing over source stars, including OGLE-2004-BLG-254, MOA-2007-BLG-176, MOA-2007-BLG-233/OGLE-2007-BLG-302, MOA-2009-BLG-174, MOA-2010-BLG-436, MOA-2011-BLG-093, MOA-2011-BLG-274, OGLE-2011-BLG-0990/MOA-2011-BLG-300, and OGLE-2011-BLG-1101/MOA-2011-BLG-325.

+info: http://adsabs.harvard.edu/abs/2012ApJ...751...41C

We search for the presence of substructure, a non-Gaussian, asymmetrical velocity distribution of galaxies, and large peculiar velocities of the main galaxies in clusters with at least 50 member galaxies, drawn from the SDSS DR8. We employ a number of 3D, 2D, and 1D tests to analyse the distribution of galaxies in clusters: 3D normal mixture modelling, the Dressler-Shectman test, the Anderson-Darling and Shapiro-Wilk tests, as well as the Anscombe-Glynn and the D'Agostino tests. We find the peculiar velocities of the main galaxies, and use principal component analysis to characterise our results.

ASTRONOMY & ASTROPHYSICS, Volume 540, id.A123, 18 pp.

We search for the presence of substructure, a non-Gaussian, asymmetrical velocity distribution of galaxies, and large peculiar velocities of the main galaxies in clusters with at least 50 member galaxies, drawn from the SDSS DR8. We employ a number of 3D, 2D, and 1D tests to analyse the distribution of galaxies in clusters: 3D normal mixture modelling, the Dressler-Shectman test, the Anderson-Darling and Shapiro-Wilk tests, as well as the Anscombe-Glynn and the D'Agostino tests. We find the peculiar velocities of the main galaxies, and use principal component analysis to characterise our results.

+info:  http://adsabs.harvard.edu/abs/2012A%26A...540A.123E

Microlensing can provide a useful tool to probe binary distributions down to low-mass limits of binary companions. In this paper, we analyze the light curves of eight binary-lensing events detected through the channel of high-magnification events during the seasons from 2007 to 2010.

THE ASTROPHYSICAL JOURNAL, Volume 746, Issue 2, Article id. 127, 13 pp. (2012).

Microlensing can provide a useful tool to probe binary distributions down to low-mass limits of binary companions. In this paper, we analyze the light curves of eight binary-lensing events detected through the channel of high-magnification events during the seasons from 2007 to 2010.

+info:  http://adsabs.harvard.edu/abs/2012ApJ...746..127S