Ricardo Fuentes Covarrubias

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We present constraints on the dark energy equation-of-state parameter, w = P/(ρc 2), using 60 Type Ia supernovae (SNe Ia) from the ESSENCE su-pernova survey. We derive a set of constraints on the nature of the dark energy assuming a flat Universe. By including constraints on (Ω M , w) from baryon acoustic oscillations, we obtain a value for a static(More)
We present a new compilation of Type Ia supernovae (SNe Ia), a new dataset of low-redshift nearby-Hubble-flow SNe and new analysis procedures to work with these heterogeneous compilations. This " Union " compilation of 414 SN Ia, which reduces to 307 SNe after selection cuts, includes the recent large samples of SNe Ia from the Supernova Legacy Survey and(More)
We present spectroscopic and photometric observations of SN 1992ar, the more distant SN in the Calán/Tololo Survey. We compare its spectrum with those of nearby Type Ia and Ic SNe and conclude that the latter type is a better match to SN 1992ar. Using K–corrections based on the spectra of well observed Type Ic and Ia SNe we compute different possible rest(More)
3 Based in part on observations taken with the Very Large Telescope under ESO program 170.A-0519. – 3 – We present broad-band light curves of nine supernovae ranging in redshift from 0.5 to 0.8. The supernovae were discovered as part of the ESSENCE project, and the light curves are a combination of Cerro Tololo 4-m and Hubble Space Telescope (HST)(More)
SN 1999aw was discovered during the first campaign of the Nearby Galaxies Supernova Search (NGSS) project. This luminous, slow-declining (∆m 15 (B)= 0.81 ± 0.03) Type Ia supernova was noteworthy in at least two respects. First, it occurred in an extremely low luminosity host galaxy that was not visible in the template images, nor in initial subsequent deep(More)
We describe the operation and performance of the difference imaging pipeline (DiffImg) used to detect transients in deep images from the Dark Energy Survey Supernova program (DES-SN) in its first observing season from 2013 August through 2014 February. DES-SN is a search for transients in which ten 3 deg 2 fields are repeatedly observed in the g, r, i, z(More)
– 3 – Using archival data of low-redshift (z < 0.01; CfA and SUSPECT databases) Type Ia supernovae (SN Ia) and recent observations of high-redshift (0.16 < z < 0.64; Matheson et al. 2005) SN Ia, we study the " uniformity " of the spectroscopic properties of nearby and distant SN Ia. We find no difference in the measures we describe here. In this paper, we(More)
We describe an algorithm for identifying point-source transients and moving objects on reference-subtracted optical images containing artifacts of processing and instrumentation. The algorithm makes use of the supervised machine learning technique known as Random Forest. We present results from its use in the Dark Energy Survey Supernova program (DES-SN),(More)
This paper discusses the overall design and implementation of a video sensor for the detection of risky behaviors of car drivers near previously identified and georeferenced black spots. The main goal is to provide the driver with a visual audio alert that informs of the proximity of an area of high incidence of highway accidents only if their driving(More)
We present the first large-scale effort of creating composite spectra of high-redshift type Ia super-novae (SNe Ia) and comparing them to low-redshift counterparts. Through the ESSENCE project, we have obtained 107 spectra of 88 high-redshift SNe Ia with excellent light-curve information. In addition, we have obtained 397 spectra of low-redshift SNe through(More)