População de plantas e taxa de rebrota de seis cruzamentos interespecíficos de "Sorghum bicolor" e "Sorghum sudanense".

Foram avaliados o número de plantas e a taxa de rebrota de quatro híbridos experimentais e dois híbridos comerciais de sorgo com capim Sudão. Nos primeiros cortes de ambas as épocas ocorreram diferenças significativas (p<0,05) entre os híbridos quanto ao número de plantas, sendo que no primeiro corte da época 1, o híbrido ATF 54 x CMSXS 912 foi semelhante aos híbridos BRS 800 e CMSXS 156 x CMSXS 912, sendo superior aos demais híbridos. No primeiro corte da segunda época, o híbrido ATF54 x CMSXS 912 apresentou número de plantas semelhantes aos híbridos AG2501C, BRS 800 e CMSXS 157 x CMSXS 912, porém superiores aos híbridos CMSXS 156 x CMSXS 912 e CMSXS 210 x CMSXS 912. Já na segunda época de plantio, os híbridos AG2501C, BRS 800 e ATF 54 x CMSXS 912 tiveram seu número de plantas reduzido a partir do segundo corte, enquanto os híbridos CMSXS 156 X CMSXS 912, CMSXS 157 x CMSXS 912, CMSXS 210 x CMSXS 912 mantiveram o número de plantas até o segundo corte, a partir do qual também houve redução. A média do número de plantas/ha foi significativamente (p<0,05) maior na época 1, com média de 841,66 mil plantas/ha. As taxas médias de rebrota foram inferiores a 1,00, não havendo diferença entre híbridos. Não houve diferença significativa (p<0,05) para as médias de rebrota entre híbridos, com exceção do híbrido AG2501C (testemunha) que, na rebrota 1, apresentou valor superior na época 1. O híbridos analisados apresentam uma boa quantidade de plantas por hectare e ótima taxa de rebrota

Produção de matéria verde, matéria seca e matéria seca digestível de hibridos de "Sorghum bicolor" com "Sorghum sudanense".

Foram avaliadas as produções de matéria verde (MV), matéria seca (MS) e matéria seca digestível (MSDG) de seis híbridos de "Sorghum bicolor" com "Sorghum sudanense". Foram utilizados dois híbridos comerciais e quatro híbridos experimentais. Utilizou-se um delineamento experimental de blocos ao acaso, com quatro repetições de seis híbridos plantados em duas épocas diferentes e submetidos a três cortes consecutivos. As análises foram feitas utilizando-se o teste SNK (p0,05) entre os híbridos para a produção media de MV e MS, com valores variando de 13,63 a 18,37 e 1,71 a 2,28 t/ha, respectivamente. A média de produção de MV e MS da época 2 foi significativamente (p0,05) entre híbridos, com valores entre 0,96 a 1,28 t/ha. Na época 1 não houve diferença entre híbridos dentro de cada corte. A época 2 apresentou média de produção de MSDG superior à época 1. A produção de MSDG apresentou correlação de 0,99 (p<0,0001) com a produção de MS. Não houve diferença entre os híbridos para as produções totais de MSDG, com valores entre 2,87 a 3,86 t/ha

Teores de cinzas, cálcio e fósforo de seis híbridos de "Sorghum bicolor" com "Sorghum sudanense" plantados em duas diferentes épocas e cortados em três diferentes períodos.

Foram avaliados o teor de cinzas e a composição mineral de seis híbridos de sorgo desenvolvidos pela EMBRAPA Milho e Sorgo. Utilizou-se um delineamento experimental de blocos ao acaso, utilizando-se quatro repetições por híbrido. Os dados foram submetidos à análise de variância, sendo as interações significativas desdobradas e as médias comparadas utilizando-se o teste de SNK a 5% de probabilidade. Não houve diferença estatística entre as médias dos híbridos para o teor médio de cinzas, sendo que os valores variaram de 6,92 a 7,46 %. Houve diferença significativa (p<0,05) entre as médias dos híbridos para a porcentagem de cálcio e fósforo. O híbrido testemunha BRS 800 apresentou os maiores teores de fósforo. De acordo com os resultados obtidos neste trabalho, conclui-se que os híbridos estudados apresentam boa composição em minerais

Brown dwarf census with the Dark Energy Survey year 3 data and the thin disc scale height of early L types

27 pages, 18 figuresIn this paper we present a catalogue of 11 745 brown dwarfs with spectral types ranging from L0 to T9, photometrically classified using data from the Dark Energy Survey (DES) year 3 release matched to the Vista Hemisphere Survey (VHS) DR3 and Wide-field Infrared Survey Explorer (WISE) data, covering ≈2400 deg2 up to iAB = 22. The classification method follows the same phototype method previously applied to SDSS-UKIDSS-WISE data. The most significant difference comes from the use of DES data instead of SDSS, which allow us to classify almost an order of magnitude more brown dwarfs than any previous search and reaching distances beyond 400 pc for the earliest types. Next, we also present and validate the GalmodBD simulation, which produces brown dwarf number counts as a function of structural parameters with realistic photometric properties of a given survey. We use this simulation to estimate the completeness and purity of our photometric LT catalogue down to iAB = 22, as well as to compare to the observed number of LT types. We put constraints on the thin disc scale height for the early L (L0–L3) population to be around 450 pc, in agreement with previous findings. For completeness, we also publish in a separate table a catalogue of 20 863 M dwarfs that passed our colour cut with spectral types greater than M6. Both the LT and the late M catalogues are found at DES release page https://des.ncsa.illinois.edu/releases/other/y3-mlt.Peer reviewedFinal Published versio

Astrometric calibration and performance of the Dark Energy Camera

We characterize the ability of the Dark Energy Camera (DECam) to perform relative astrometry across its 500~Mpix, 3 deg^2 science field of view, and across 4 years of operation. This is done using internal comparisons of ~4x10^7 measurements of high-S/N stellar images obtained in repeat visits to fields of moderate stellar density, with the telescope dithered to move the sources around the array. An empirical astrometric model includes terms for: optical distortions; stray electric fields in the CCD detectors; chromatic terms in the instrumental and atmospheric optics; shifts in CCD relative positions of up to ~10 um when the DECam temperature cycles; and low-order distortions to each exposure from changes in atmospheric refraction and telescope alignment. Errors in this astrometric model are dominated by stochastic variations with typical amplitudes of 10-30 mas (in a 30 s exposure) and 5-10 arcmin coherence length, plausibly attributed to Kolmogorov-spectrum atmospheric turbulence. The size of these atmospheric distortions is not closely related to the seeing. Given an astrometric reference catalog at density ~0.7 arcmin^{-2}, e.g. from Gaia, the typical atmospheric distortions can be interpolated to 7 mas RMS accuracy (for 30 s exposures) with 1 arcmin coherence length for residual errors. Remaining detectable error contributors are 2-4 mas RMS from unmodelled stray electric fields in the devices, and another 2-4 mas RMS from focal plane shifts between camera thermal cycles. Thus the astrometric solution for a single DECam exposure is accurate to 3-6 mas (0.02 pixels, or 300 nm) on the focal plane, plus the stochastic atmospheric distortion.Comment: Submitted to PAS

Evidence for Color Dichotomy in the Primordial Neptunian Trojan Population

In the current model of early Solar System evolution, the stable members of the Jovian and Neptunian Trojan populations were captured into resonance from the leftover reservoir of planetesimals during the outward migration of the giant planets. As a result, both Jovian and Neptunian Trojans share a common origin with the primordial disk population, whose other surviving members constitute today's trans-Neptunian object (TNO) populations. The cold classical TNOs are ultra-red, while the dynamically excited "hot" population of TNOs contains a mixture of ultra-red and blue objects. In contrast, Jovian and Neptunian Trojans are observed to be blue. While the absence of ultra-red Jovian Trojans can be readily explained by the sublimation of volatile material from their surfaces due to the high flux of solar radiation at 5AU, the lack of ultra-red Neptunian Trojans presents both a puzzle and a challenge to formation models. In this work we report the discovery by the Dark Energy Survey (DES) of two new dynamically stable L4 Neptunian Trojans,2013 VX30 and 2014 UU240, both with inclinations i >30 degrees, making them the highest-inclination known stable Neptunian Trojans. We have measured the colors of these and three other dynamically stable Neptunian Trojans previously observed by DES, and find that 2013 VX30 is ultra-red, the first such Neptunian Trojan in its class. As such, 2013 VX30 may be a "missing link" between the Trojan and TNO populations. Using a simulation of the DES TNO detection efficiency, we find that there are 162 +/- 73 Trojans with Hr < 10 at the L4 Lagrange point of Neptune. Moreover, the blue-to-red Neptunian Trojan population ratio should be higher than 17:1. Based on this result, we discuss the possible origin of the ultra-red Neptunian Trojan population and its implications for the formation history of Neptunian Trojans

H0LiCOW X: Spectroscopic/imaging survey and galaxy-group identification around the strong gravitational lens system WFI2033-4723

Galaxies and galaxy groups located along the line of sight towards gravitationally lensed quasars produce high-order perturbations of the gravitational potential at the lens position. When these perturbation are too large, they can induce a systematic error on $H_0$ of a few-percent if the lens system is used for cosmological inference and the perturbers are not explicitly accounted for in the lens model. In this work, we present a detailed characterization of the environment of the lens system WFI2033-4723 ($z_{\rm src} = 1.662$, $z_{\rm lens}$ = 0.6575), one of the core targets of the H0LICOW project for which we present cosmological inferences in a companion paper (Rusu et al. 2019). We use the Gemini and ESO-Very Large telescopes to measure the spectroscopic redshifts of the brightest galaxies towards the lens, and use the ESO-MUSE integral field spectrograph to measure the velocity-dispersion of the lens ($\sigma_{\rm {los}}= 250^{+15}_{-21}$ km/s) and of several nearby galaxies. In addition, we measure photometric redshifts and stellar masses of all galaxies down to $i < 23$ mag, mainly based on Dark Energy Survey imaging (DR1). Our new catalog, complemented with literature data, more than doubles the number of known galaxy spectroscopic redshifts in the direct vicinity of the lens, expanding to 116 (64) the number of spectroscopic redshifts for galaxies separated by less than 3 arcmin (2 arcmin) from the lens. Using the flexion-shift as a measure of the amplitude of the gravitational perturbation, we identify 2 galaxy groups and 3 galaxies that require specific attention in the lens models. The ESO MUSE data enable us to measure the velocity-dispersions of three of these galaxies. These results are essential for the cosmological inference analysis presented in Rusu et al. (2019).Comment: Matches the version accepted for publication by MNRAS. Note that this paper previously appeared as H0LICOW X