ORCID Profile
0000-0002-6211-7226
Current Organisations
Universidade de São Paulo
,
Universidade Federal de Sergipe
,
Universite de Strasbourg UFR de physique et ingenierie
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Springer Science and Business Media LLC
Date: 13-04-2020
Publisher: Oxford University Press (OUP)
Date: 05-08-2019
Abstract: The Southern Photometric Local Universe Survey (S-PLUS) is imaging ∼9300 deg2 of the celestial sphere in 12 optical bands using a dedicated 0.8 m robotic telescope, the T80-South, at the Cerro Tololo Inter-american Observatory, Chile. The telescope is equipped with a 9.2k × 9.2k e2v detector with 10 $\rm {\mu m}$ pixels, resulting in a field of view of 2 deg2 with a plate scale of 0.55 arcsec pixel−1. The survey consists of four main subfields, which include two non-contiguous fields at high Galactic latitudes (|b| & 30°, 8000 deg2) and two areas of the Galactic Disc and Bulge (for an additional 1300 deg2). S-PLUS uses the Javalambre 12-band magnitude system, which includes the 5 ugriz broad-band filters and 7 narrow-band filters centred on prominent stellar spectral features: the Balmer jump/[OII], Ca H + K, H δ, G band, Mg b triplet, H α, and the Ca triplet. S-PLUS delivers accurate photometric redshifts (δz/(1 + z) = 0.02 or better) for galaxies with r & 19.7 AB mag and z & 0.4, thus producing a 3D map of the local Universe over a volume of more than $1\, (\mathrm{Gpc}/h)^3$. The final S-PLUS catalogue will also enable the study of star formation and stellar populations in and around the Milky Way and nearby galaxies, as well as searches for quasars, variable sources, and low-metallicity stars. In this paper we introduce the main characteristics of the survey, illustrated with science verification data highlighting the unique capabilities of S-PLUS. We also present the first public data release of ∼336 deg2 of the Stripe 82 area, in 12 bands, to a limiting magnitude of r = 21, available at plus.
Publisher: American Astronomical Society
Date: 08-2022
Abstract: We report the discovery of 1RXH J082623.6−505741, a 10.4 hr orbital period compact binary. Modeling extensive optical photometry and spectroscopy reveals a ∼0.4 M ⊙ K-type secondary transferring mass through a low-state accretion disk to a nonmagnetic ∼0.8 M ⊙ white dwarf. The secondary is overluminous for its mass and dominates the optical spectra at all epochs and must be evolved to fill its Roche Lobe at this orbital period. The X-ray luminosity L X ∼ 1–2 × 10 32 erg s −1 derived from both new XMM-Newton and archival observations, although high compared to most CVs, still only requires a modest accretion rate onto the white dwarf of M ̇ ∼ 3 × 10 −11 to 3 × 10 −10 M ⊙ yr −1 , lower than expected for a cataclysmic variable with an evolved secondary. No dwarf nova outbursts have yet been observed from the system, consistent with the low derived mass-transfer rate. Several other cataclysmic variables with similar orbital periods also show unexpectedly low mass-transfer rates, even though selection effects disfavor the discovery of binaries with these properties. This suggests the abundance and evolutionary state of long-period, low mass-transfer rate cataclysmic variables are worthy of additional attention.
Publisher: Oxford University Press (OUP)
Date: 02-02-2022
Abstract: The Southern Photometric Local Universe Survey (S-PLUS) is an ongoing survey of ∼9300 deg2 in the southern sky in a 12-band photometric system. This paper presents the second data release (DR2) of S-PLUS, consisting of 514 tiles covering an area of 950 deg2. The data has been fully calibrated using a new photometric calibration technique suitable for the new generation of wide-field multifilter surveys. This technique consists of a χ2 minimization to fit synthetic stellar templates to already calibrated data from other surveys, eliminating the need for standard stars and reducing the survey duration by ∼15 per cent. We compare the template-predicted and S-PLUS instrumental magnitudes to derive the photometric zero-points (ZPs). We show that these ZPs can be further refined by fitting the stellar templates to the 12 S-PLUS magnitudes, which better constrain the models by adding the narrow-band information. We use the STRIPE82 region to estimate ZP errors, which are ≲ 10 mmags for filters J0410, J0430, g, J0515, r, J0660, i, J0861 and z ≲ 15 mmags for filter J0378 and ≲ 25 mmags for filters u and J0395. We describe the complete data flow of the S-PLUS/DR2 from observations to the final catalogues and present a brief characterization of the data. We show that, for a minimum signal-to-noise threshold of 5, the photometric depths of the DR2 range from 19.1 to 20.5 mag (measured in Petrosian apertures), depending on the filter. The S-PLUS DR2 can be accessed from the website: splus.cloud.
Publisher: Oxford University Press (OUP)
Date: 04-06-2020
Abstract: In this paper we present a thorough discussion about the photometric redshift (photo-z) performance of the Southern Photometric Local Universe Survey (S-PLUS). This survey combines a seven narrow +5 broad passband filter system, with a typical photometric-depth of r ∼ 21 AB. For this exercise, we utilize the Data Release 1 (DR1), corresponding to 336 deg2 from the Stripe-82 region. We rely on the BPZ2 code to compute our estimates, using a new library of SED models, which includes additional templates for quiescent galaxies. When compared to a spectroscopic redshift control s le of ∼100 k galaxies, we find a precision of σz & .8 per cent, & .0 per cent, or & .0 per cent for galaxies with magnitudes r & 17, & , and & , respectively. A precision of 0.6 per cent is attained for galaxies with the highest Odds values. These estimates have a negligible bias and a fraction of catastrophic outliers inferior to 1 per cent. We identify a redshift window (i.e. 0.26 & z & 0.32) where our estimates double their precision, due to the simultaneous detection of two emission lines in two distinct narrow bands representing a window opportunity to conduct statistical studies such as luminosity functions. We forecast a total of ∼2 M, ∼16 M and ∼32 M galaxies in the S-PLUS survey with a photo-z precision of σz & .0 per cent, & .0 per cent, and & .5 per cent after observing 8000 deg2. We also derive redshift probability density functions, proving their reliability encoding redshift uncertainties and their potential recovering the n(z) of galaxies at z & 0.4, with an unprecedented precision for a photometric survey in the Southern hemisphere.
Location: United States of America
Location: France
No related grants have been discovered for Raimundo Lopes de Oliveira.