Examinando por Autor "Santana-Silva L."

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    Assessing the photometric redshift precision of the S-PLUS survey: The Stripe-82 as a test-case
    (Oxford University Press, 2020-12) Molino A.; Costa-Duarte M.V.; Sampedro L.; Herpich F.R.; Sodré L.; Jr. Mendes de Oliveira C.; Schoenell W.; Barbosa C.E.; Queiroz C.; Lima E.V.R.; Azanha L.; Muñoz-Elgueta N.; Ribeiro T.; Kanaan A.; Hernandez-Jimenez J.A.; Cortesi A.; Akras S.; Lopes de Oliveira R.; Torres-Flores S.; Lima-Dias C.; Nilo Castellon J.L.; Damke G.; Alvarez-Candal A.; Jiménez-Teja Y.; Coelho P.; Pereira E.; Montero-Dorta A.D.; Benítez N.; Gonçalves T.S.; Santana-Silva L.; Werner S.V.; Almeida L.A.; Lopes P.A.A.; Chies-Santos A.L.; Telles E.; Thom de Souza R.C.; Gonçalves D.R.; de Souza R.S.; Makler M.; Buzzo M.L.; Placco V.M.; Nakazono L.M.I.; Saito R.K.; Overzier R.A.; Abramo L.R.
    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 sample of ∼100 k galaxies, we find a precision of σz <0.8 per cent, <2.0 per cent, or <3.0 per cent for galaxies with magnitudes r < 17, <19, and <21, 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 <1.0 per cent, <2.0 per cent, and <2.5 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. © 2020 The Author(s)
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    Ítem
    Designing an Optimal Kilonova Search Using DECam for Gravitational-wave Events
    (Institute of Physics, 2024-02) Bom C.R.; Annis J.; Garcia A.; Palmese A.; Sherman N.; Soares-Santos M.; Santana-Silva L.; Morgan R.; Bechtol K.; Davis T.; Diehl H.T.; Allam S.S.; Bachmann T.G.; Fraga B.M.O.; García-Bellido J.; Gill M.S.S.; Herner K.; Kilpatrick C.D.; Makler M.; Olivares E. F.; Pereira M.E.S.; Pineda J.; Santos A.; Tucker D.L.; Wiesner M.P.; Aguena M.; Alves O.; Bacon D.; Bernardinelli P.H.; Bertin E.; Bocquet S.; Brooks D.; Carrasco Kind M.; Carretero J.; Conselice C.; Costanzi M.; da Costa L.N.; De Vicente J.; Desai S.; Doel P.; Everett S.; Ferrero I.; Frieman J.; Gatti M.; Gerdes D.W.; Gruen D.; Gruendl R.A.; Gutierrez G.; Hinton S.R.; Hollowood D.L.; Honscheid K.; James D.J.; Kuehn K.; Kuropatkin N.; Melchior P.; Mena-Fernández J.; Menanteau F.; Pieres A.; Plazas Malagón A.A.; Raveri M.; Rodriguez-Monroy M.; Sanchez E.; Santiago B.; Sevilla-Noarbe I.; Smith M.; Suchyta E.; Swanson M.E.C.; Tarle G.; To C.; Weaverdyck N.
    We address the problem of optimally identifying all kilonovae detected via gravitational-wave emission in the upcoming LIGO/Virgo/KAGRA observing run, O4, which is expected to be sensitive to a factor of ∼7 more binary neutron star (BNS) alerts than previously. Electromagnetic follow-up of all but the brightest of these new events will require >1 m telescopes, for which limited time is available. We present an optimized observing strategy for the DECam during O4. We base our study on simulations of gravitational-wave events expected for O4 and wide-prior kilonova simulations. We derive the detectabilities of events for realistic observing conditions. We optimize our strategy for confirming a kilonova while minimizing telescope time. For a wide range of kilonova parameters, corresponding to a fainter kilonova compared to GW170817/AT 2017gfo, we find that, with this optimal strategy, the discovery probability for electromagnetic counterparts with the DECam is ∼80% at the nominal BNS gravitational-wave detection limit for O4 (190 Mpc), which corresponds to an ∼30% improvement compared to the strategy adopted during the previous observing run. For more distant events (∼330 Mpc), we reach an ∼60% probability of detection, a factor of ∼2 increase. For a brighter kilonova model dominated by the blue component that reproduces the observations of GW170817/AT 2017gfo, we find that we can reach ∼90% probability of detection out to 330 Mpc, representing an increase of ∼20%, while also reducing the total telescope time required to follow up events by ∼20%. © 2024. The Author(s). Published by the American Astronomical Society.