Mapping Debris Disks at extreme contrast: near-IR Polarimetric Differential Imaging with the Gemini Planet Imager.

Debris disks are gas-poor evolved circumstellar disks that show decreased near- to mid- infrared thermal excess emission because of lack of material close to the star. Regarded as massive analogues to the Main Asteroid or Kuiper Belts in the Solar System, these often young dust-rich disks comprise second-generation dust created by disruptive collisions of planetesimals and the decay products of asteroids and comets. Of the dozen or so directly imaged planets to date many share a distinctive characteristic: they reside in stellar systems known to also possess circumstellar dust. High-angular resolution characterization of debris disks, whose morphology is thought to be affected by embedded orbiting planets, offers an important offers an important pathway for probing planet-disk interaction. I used polarimetric differential imaging (PDI) to characterize debris disk at 0.042” resolution with the Gemini Planet Imager (GPI) on the Gemini South 8 m telescope. For the first project, I determined the photometric response of polarimetric observations with GPI leading to the flux calibration of the instrument. In my second and third project, I demonstrated the utility of PDI with radiative transfer modeling tools to characterize the morphology and grain properties of two debris disks at solar system scales. I reported the first PDI observations of the inner Kuiper Belt-analog HD 141569A disk and revealed the presence of an spiral arm. I also determined the existence of a putative unseen innermost disk inwards of 30 AU around HD 141569A through the analysis of the predicted thermal emission of the disk. Finally, I mapped the structure of the 82 AU ring-shaped HD 157587 debris disk. Our multi-wavelength high-contrast polarimetry reveals that even this unusually old (\u3e 1 billion years) debris disk contains short-lived small grains: evidence of an active collisional cascade in this system. The combined power of extreme contrast (∼ 1 : 1, 000, 000 at 1 arc second), high angular resolution, and differential polarimetry with the Gemini Planet Imager reveals previously unseen disk structures, and is of great value for studying dynamically perturbed disks

Observations of an Unexpected Meteor Shower Outburst at High Ecliptic Southern Latitude and Its Potential Origin

A strong and unexpected meteor shower outburst was observed by the Southern Argentina Agile MEteor Radar Orbital System (SAAMER-OS) at high southern ecliptic latitude within the South Toroidal region. The outburst, which was active throughout solar longitudes 351° and 352°, peaked at 09:30 UT on 2020 March 12, has a mean Sun-centered ecliptic radiant of λ-λ 0 ∼ 307.°5 and β ∼-77.°2 and a geocentric velocity of 30.7 km s-1. Using the D′parameter criterion, we find the corresponding orbital elements of the outburst to match well with both the β Tucanid and δ Mensid meteor showers, suggesting these are in fact the same shower. We also find a promising parent candidate in asteroid (248590) 2006 CS, a large (D ∼ 2 km) highly inclined 52° near-Earth object.Fil: Janches, Diego. Nasa Goddard Space Flight Center; Estados UnidosFil: Bruzzone, Juan Sebastian. Nasa Goddard Space Flight Center; Estados UnidosFil: Weryk, Robert J.. University of Hawaii at Manoa; Estados UnidosFil: Hormaechea, José Luis. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Wiegert, Paul. Public Health Ontario; CanadáFil: Brunini, Claudio Antonio. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - la Plata. Laboratorio Geo - Aggo.; Argentin

Career decision self-efficacy Item Bank: A Simulation study

The transformation of the current world of work, determined by technological advances, affects and challenges the career decision-making process. To face these changes, the career self-management model, derived from social cognitive career theory, offers an optimal framework that allows studying the career adaptive behaviors that favor the preparation for career decision-making. In order to obtain a measure for the core construct, career decision-making self-efficacy, we elaborated an item bank from the selection of reagents from two scales widely used in the field for its estimation. Item analysis was performed from the item response theory. The results evidenced the unidimensionality of the item pool, with difficulty indexes and ability levels covering most of the measured continuum. As regard reliability indexes (persons and items), we observed that the allocation of persons and items might be reproduced in a predictable way. Global fit of items was suitable in most of them. We also performed two analyses of the evidence of the validity of the scores obtained through the Career Decision Making Self-Efficacy-Item Bank. We carried out a simulation study to determine the real level of ability of the subjects, providing information on the quality of the item bank developed to accurately assess career decision self-efficacy. Thus, we conducted a concurrent validity evidence study to establish test-criterion relationships between career decision self-efficacy and the more significant outcome variables of the career decision-making process: career decision, career indecision, and decisional anxiety. In summary, we developed, calibrated, and validated the first item bank to estimate the central construct of the career decision-making process, which is the first step to develop a Computerized Adaptive Test. Based on this technology, personalized evaluations of specific skills or traits such as career decision self-efficacy can be obtained and incorporated into computer-assisted career guidance systems.Fil: Azpilicueta, Ana Estefanía. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; ArgentinaFil: Cupani, Marcos. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Psicología; ArgentinaFil: Ghio, Fernanda Belén. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; ArgentinaFil: Moran, Valeria Estefania. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; Argentina. Universidad Empresarial Siglo XXI; ArgentinaFil: Garrido, Sebastian Jesús. Universidad Nacional de Córdoba. Facultad de Psicología; Argentina. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; ArgentinaFil: Bruzzone, Manuel. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; Argentin

Bringing "The Moth" to Light: A Planet-Sculpting Scenario for the HD 61005 Debris Disk

The HD 61005 debris disk ("The Moth") stands out from the growing collection of spatially resolved circumstellar disks by virtue of its unusual swept-back morphology, brightness asymmetries, and dust ring offset. Despite several suggestions for the physical mechanisms creating these features, no definitive answer has been found. In this work, we demonstrate the plausibility of a scenario in which the disk material is shaped dynamically by an eccentric, inclined planet. We present new Keck NIRC2 scattered-light angular differential imaging of the disk at 1.2-2.3 microns that further constrains its outer morphology (projected separations of 27-135 AU). We also present complementary Gemini Planet Imager 1.6 micron total intensity and polarized light detections that probe down to projected separations less than 10 AU. To test our planet-sculpting hypothesis, we employed secular perturbation theory to construct parent body and dust distributions that informed scattered-light models. We found that this method produced models with morphological and photometric features similar to those seen in the data, supporting the premise of a planet-perturbed disk. Briefly, our results indicate a disk parent body population with a semimajor axis of 40-52 AU and an interior planet with an eccentricity of at least 0.2. Many permutations of planet mass and semimajor axis are allowed, ranging from an Earth mass at 35 AU to a Jupiter mass at 5 AU.Comment: Accepted to AJ; added Figure 5 and minor text edit

Observation of the A Carinid Meteor Shower 2020 Unexpected Outburst

We present observations of the sudden outburst of the A Carinid meteor shower recorded with the Southern Argentina Agile MEteor Radar Orbital System (SAAMER-OS) near the south toroidal sporadic region. The outburst peaked between 21 UT and 22 UT on 2020 October 14 and lasted 7 days (199° ≤ λ ⊙ ≤ 205°), with a mean Sun-centered geocentric ecliptic radiant of λ g − λ ⊙ = 271.°04, β g = −76.°4, and a geocentric speed of 33.3 km s−1. Assuming a mass index value of s = 2.0, we compute a peak 24 hr average flux of 0.029 meteoroids km−2 hr−1 to a limit of 9th magnitude, which is equivalent to a zenithal hourly rate (ZHR) of 5.7 and comparable to other established showers with similar mass indices. By further estimating the peak fluxes for other typical mass index values, we find that the outburst likely never exceeded a maximum ZHR of ∼44, well below the activity of other strong showers. The mean orbital elements resemble those of a short-period object, a = 3.5 ± 0.1 au, q ≃ 1 au, e = 0.72 ± 0.02, i = 55.°8 ± 0.°3, ω = 1° ± 173°, and Ω = 21.°7, and are similar to those derived for two previous shower outbursts observed with SAAMER-OS at high southern ecliptic latitudes. Using the criterion did not reveal a parent object associated with this shower in the known object catalogs

Automated data processing architecture for the Gemini Planet Imager Exoplanet Survey

The Gemini Planet Imager Exoplanet Survey (GPIES) is a multi-year direct imaging survey of 600 stars to discover and characterize young Jovian exoplanets and their environments. We have developed an automated data architecture to process and index all data related to the survey uniformly. An automated and flexible data processing framework, which we term the Data Cruncher, combines multiple data reduction pipelines together to process all spectroscopic, polarimetric, and calibration data taken with GPIES. With no human intervention, fully reduced and calibrated data products are available less than an hour after the data are taken to expedite follow-up on potential objects of interest. The Data Cruncher can run on a supercomputer to reprocess all GPIES data in a single day as improvements are made to our data reduction pipelines. A backend MySQL database indexes all files, which are synced to the cloud, and a front-end web server allows for easy browsing of all files associated with GPIES. To help observers, quicklook displays show reduced data as they are processed in real-time, and chatbots on Slack post observing information as well as reduced data products. Together, the GPIES automated data processing architecture reduces our workload, provides real-time data reduction, optimizes our observing strategy, and maintains a homogeneously reduced dataset to study planet occurrence and instrument performance.Comment: 21 pages, 3 figures, accepted in JATI

Una herramienta para monitorear sequías en regiones áridas y semiáridas de Patagonia Norte

La variabilidad ambiental es una característica de regiones pastoriles áridas y semiáridas, siendo la sequía uno de los principales problemas en sistemas ganaderos extensivos, con implicancias productivas y económicas tanto a escala predial como regional. El monitoreo regional de los procesos de sequía es una herramienta fundamental y necesaria, como complemento de propuestas y manejos adaptativos activos que busquen mitigar los impactos sobre la producción. En el presente artículo proponemos una herramienta para el monitoreo de sequías en zonas áridas y semiáridas, basada en datos provistos por sensores remotos. El objetivo fue desarrollar un sistema de monitoreo basado en un índice espectral, desagregando la heterogeneidad biofísica regional en unidades homogéneas, y relacionándola con los momentos clave de decisiones asociadas al manejo ganadero tradicional, en sistemas de producción ovina de Patagonia Norte. Esta integración permite acercar esta herramienta a la toma de decisiones a escala regional, fundamentalmente para instituciones y organizaciones locales, y colaborar con información en el diseño y desarrollo de políticas vinculadas al manejo ganadero adaptativo. Finalmente, discutimos los alcances de la herramienta y los desafíos futuros, asociados al desarrollo de sistemas de alerta temprana y mitigación de sequías en regiones áridas y semiáridas.Environmental variability is a constant feature in arid and semiarid rangeland regions, being drought one of the main problems in extensive livestock production, with productive and economic impacts both at farm and regional scales. Regional monitoring of drought processes is a key and necessary tool, as a complement for active adaptive proposals and management, aimed at mitigation on production impacts. In this article, we propose a tool for drought monitoring in arid and semiarid areas, based on remote sensing data. The aim was to develop a monitoring system based on a spectral index, disaggregating regional biophysical heterogeneity into homogeneous units, by linking them to key decision moments associated with traditional livestock management in sheep farming systems from Northern Patagonia. Such integration allows bringing this tool closer to regional decision making, basically for local institutions and organizations, and give support with information for policy design and development related to adaptive livestock management. Finally, we discuss the scope of this tool and future challenges, regarding the development of early warning and drought mitigation systems in arid and semiarid regions.EEA BarilocheFil: Easdale, Marcos Horacio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área de Desarrollo Rural; ArgentinaFil: Lopez, Dardo Ruben. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área de Recursos Naturales; ArgentinaFil: Bianchi, Emilio. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bruzzone, Octavio Augusto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Villagra, Edgar Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Siffredi, Guillermo Lorenzo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área de Recursos Naturales; ArgentinaFil: Gaitan, Juan Jose. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche. Área de Recursos Naturales; ArgentinaFil: Umaña, Fernando. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; ArgentinaFil: Oricchio, Patricio. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Clima y Agua; Argentin

The Gemini Planet Imager View of the HD 32297 Debris Disk

We present new H-band scattered light images of the HD 32297 edge-on debris disk obtained with the Gemini Planet Imager. The disk is detected in total and polarized intensity down to a projected angular separation of 0.?15, or 20 au. On the other hand, the large-scale swept-back halo remains undetected, likely a consequence of its markedly blue color relative to the parent body belt. We analyze the curvature of the disk spine and estimate a radius of ?100 au for the parent body belt, smaller than past scattered light studies but consistent with thermal emission maps of the system. We employ three different flux-preserving post-processing methods to suppress the residual starlight and evaluate the surface brightness and polarization profile along the disk spine. Unlike past studies of the system, our high-fidelity images reveal the disk to be highly symmetric and devoid of morphological and surface brightness perturbations. We find the dust scattering properties of the system to be consistent with those observed in other debris disks, with the exception of HR 4796. Finally, we find no direct evidence for the presence of a planetary-mass object in the system