75 research outputs found
Comportamiento agronómico, rendimiento productivo y calidad industrial de trece genotipos y una variedad comercial de arroz (Oryza sativa L.) bajo condiciones de riego en el Valle de Sébaco, Matagalpa, II Semestre 2016
Durante el II semestre del año 2016, se realizó la presente investigación con el objetivo de evaluar el comportamiento agronómico, rendimiento productivo y calidad industrial de trece genotipos y una variedad comercial de arroz (Oryza sativa L.) bajo condiciones de riego. El experimento se estableció en el Centro Experimental TAINIC en la comarca El Horno, municipio de Ciudad Darío, Matagalpa, siendo sus coordenadas geográficas de 12°48´51" de latitud Norte, y 86°09´53" de longitud Oeste con una altitud de 460 msnm. El diseño utilizado para evaluar los genotipos de arroz fue el de Bloques Completos al Azar con un total de un total de 14 tratamientos y 4 repeticiones. Utilizándose ANDEVA y separación de media por Tukey (∞=0.05) para determinar significancia. Los principales resultados indican que los tratamientos 7, 3 y 2 (CT18504-4-5-3Vi-2-3P, IR31917-45-3-2-1-1SR-5-M y IR77430-14-B-1-2-B-3-4SR-1-M) obtuvieron el mayor rendimiento de grano con 7582.4, 7434.5 y 7127.1 kilogramos por hectárea respectivamente. Los componentes como la habilidad de macollamiento y el número de granos por panícula fueron determinantes para obtener mayor rendimiento en los genotipos. Se destaca el hecho que según la escala CIAT 10 de los genotipos se clasifican como Semienanos y 4 de los genotipos se clasifican en la categoría intermedia. Los tratamientos acriollados 11, 12, 13 y el tratamiento testigo 14 (Tres Mesino Rojo, Enano, Fortuna e INTA L-9) obtuvieron la mejor relación entero/quebrado con 95/05, 93/07, 93/07 y 92/08 respectivamente.
Palabras claves: genotipos, rendimiento de grano, macollamiento, granos por panícul
Identifying the SN 2022acko progenitor with JWST
We report on analysis using the James Webb Space Telescope (JWST) to identify
a candidate progenitor star of the Type II-plateau supernova SN 2022acko in the
nearby, barred spiral galaxy NGC 1300. To our knowledge, our discovery
represents the first time JWST has been used to localize a progenitor system in
pre-explosion archival Hubble Space Telescope (HST) images. We astrometrically
registered a JWST NIRCam image from 2023 January, in which the SN was
serendipitously captured, to pre-SN HST F160W and F814W images from 2017 and
2004, respectively. An object corresponding precisely to the SN position has
been isolated with reasonable confidence. That object has a spectral energy
distribution (SED) and overall luminosity consistent with a single-star model
having an initial mass possibly somewhat less than the canonical 8 Msun
theoretical threshold for core collapse (although masses as high as 9 Msun for
the star are also possible); however, the star's SED and luminosity are
inconsistent with that of a super-asymptotic giant branch star which might be a
forerunner of an electron-capture SN. The properties of the progenitor alone
imply that SN 2022acko is a relatively normal SN II-P, albeit most likely a
low-luminosity one. The progenitor candidate should be confirmed with follow-up
HST imaging at late times, when the SN has sufficiently faded. This potential
use of JWST opens a new era of identifying SN progenitor candidates at high
spatial resolution.Comment: 8 pages, substantial changes from v1, to appear in MNRA
SN 2022jox: An extraordinarily ordinary Type II SN with Flash Spectroscopy
We present high cadence optical and ultraviolet observations of the Type II
supernova (SN), SN 2022jox which exhibits early spectroscopic high ionization
flash features of \ion{H}{1}, \ion{He}{2}, \ion{C}{4}, and \ion{N}{4} that
disappear within the first few days after explosion. SN 2022jox was discovered
by the Distance Less than 40 Mpc (DLT40) survey 0.75 days after explosion
with followup spectra and UV photometry obtained within minutes of discovery.
The SN reached a peak brightness of M 17.3 mag, and has an
estimated Ni mass of 0.04 M, typical values for normal Type II
SNe. The modeling of the early lightcurve and the strong flash signatures
present in the optical spectra indicate interaction with circumstellar material
(CSM) created from a progenitor with a mass loss rate of . There may also be some indication
of late-time CSM interaction in the form of an emission line blueward of
H seen in spectra around 200 days. The mass-loss rate is much higher
than the values typically associated with quiescent mass loss from red
supergiants, the known progenitors of Type II SNe, but is comparable to
inferred values from similar core collapse SNe with flash features, suggesting
an eruptive event or a superwind in the progenitor in the months or years
before explosion.Comment: Submitted to Ap
Circumstellar Medium Interaction in SN 2018lab, A Low-Luminosity II-P Supernova observed with TESS
We present photometric and spectroscopic data of SN 2018lab, a low luminosity
type IIP supernova (LLSN) with a V-band peak luminosity of mag.
SN 2018lab was discovered by the Distance Less Than 40 Mpc (DLT40) SNe survey
only 0.73 days post-explosion, as determined by observations from the
Transiting Exoplanet Survey Satellite (TESS). TESS observations of SN 2018lab
yield a densely sampled, fast-rising, early time light curve likely powered by
circumstellar medium (CSM) interaction. The blue-shifted, broadened flash
feature in the earliest spectra (2 days) of SN 2018lab provide further
evidence for ejecta-CSM interaction. The early emission features in the spectra
of SN 2018lab are well described by models of a red supergiant progenitor with
an extended envelope and close-in CSM. As one of the few LLSNe with observed
flash features, SN 2018lab highlights the need for more early spectra to
explain the diversity of flash feature morphology in type II SNe
Shock Cooling and Possible Precursor Emission in the Early Light Curve of the Type II SN 2023ixf
We present the densely sampled early light curve of the Type II supernova
(SN) 2023ixf, first observed within hours of explosion in the nearby Pinwheel
Galaxy (Messier 101; 6.7 Mpc). Comparing these data to recently updated models
of shock cooling emission, we find that the progenitor likely had a radius of
(statistical uncertainty only), consistent with a red
supergiant. These models provide a good fit to the data starting about 1 day
after the explosion, despite the fact that the classification spectrum shows
signatures of circumstellar material around SN 2023ixf during that time.
Photometry during the first day after the explosion, provided almost entirely
by amateur astronomers, does not agree with the shock cooling models or a
simple power-law rise fit to data after 1 day. We consider the possible causes
of this discrepancy, including precursor activity from the progenitor star,
circumstellar interaction, and emission from the shock before or after it
breaks out of the stellar surface. The very low luminosity () and short duration of the initial excess leads us to
prefer a scenario related to prolonged emission from the SN shock traveling
through the progenitor system.Comment: submitted to ApJ
The Rural Household Multiple Indicator Survey, data from 13,310 farm households in 21 countries
The Rural Household Multiple Indicator Survey (RHoMIS) is a standardized farm household survey approach which collects information on 758 variables covering household demographics, farm area, crops grown and their production, livestock holdings and their production, agricultural product use and variables underlying standard socio-economic and food security indicators such as the Probability of Poverty Index, the Household Food Insecurity Access Scale, and household dietary diversity. These variables are used to quantify more than 40 different indicators on farm and household characteristics, welfare, productivity, and economic performance. Between 2015 and the beginning of 2018, the survey instrument was applied in 21 countries in Central America, sub-Saharan Africa and Asia. The data presented here include the raw survey response data, the indicator calculation code, and the resulting indicator values. These data can be used to quantify on- and off-farm pathways to food security, diverse diets, and changes in poverty for rural smallholder farm households
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory
The Auger Engineering Radio Array (AERA) is part of the Pierre Auger
Observatory and is used to detect the radio emission of cosmic-ray air showers.
These observations are compared to the data of the surface detector stations of
the Observatory, which provide well-calibrated information on the cosmic-ray
energies and arrival directions. The response of the radio stations in the 30
to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of
the incoming electric field. For the latter, the energy deposit per area is
determined from the radio pulses at each observer position and is interpolated
using a two-dimensional function that takes into account signal asymmetries due
to interference between the geomagnetic and charge-excess emission components.
The spatial integral over the signal distribution gives a direct measurement of
the energy transferred from the primary cosmic ray into radio emission in the
AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air
shower arriving perpendicularly to the geomagnetic field. This radiation energy
-- corrected for geometrical effects -- is used as a cosmic-ray energy
estimator. Performing an absolute energy calibration against the
surface-detector information, we observe that this radio-energy estimator
scales quadratically with the cosmic-ray energy as expected for coherent
emission. We find an energy resolution of the radio reconstruction of 22% for
the data set and 17% for a high-quality subset containing only events with at
least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO
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