Tomographic Simulations of Accretion Disks in Cataclysmic Variables - Flickering and Wind

Both continuum and emission line flickering are phenomena directly associated with the mass accretion process. In this work we simulate accretion disk Doppler maps including the effects of winds and flickering flares. Synthetic flickering Doppler maps are calculated and the effect of the flickering parameters on the maps is explored. Jets and winds occur in many astrophysical objects where accretion disks are present. Jets are generally absent among the cataclysmic variables (CVs), but there is evidence of mass loss by wind in many objects. CVs are ideal objects to study accretion disks and consequently to study the wind associated with these disks. We also present simulations of accretion disks including the presence of a wind with orbital phase resolution. Synthetic H-alpha line profiles in the optical region are obtained and their corresponding Doppler maps are calculated. The effect of the wind simulation parameters on the wind line profiles is also explored. From this study we verified that optically thick lines and/or emission by diffuse material into the primary Roche lobe are necessary to generate single peaked line profiles, often seen in CVs. The future accounting of these effects is suggested for interpreting Doppler tomography reconstructions.Comment: 9 pages, 9 figure

A Spectroscopic Analysis of Accretion Disks in Cataclysmic Variables

Neste trabalho é apresentado um estudo observacional de discos de acresção em Variáveis Cataclísmicas (VCs). São analisadas medidas espectrofotométricas com resolução temporal dos perfis de linhas de emissão. A emissividade em linhas dos sistemas é mapeada utilizando a técnica de tomografia Doppler. Os parâmetros básicos das binárias, tais como período orbital, massas, inclinação orbital, são determinados quando necessário. Um código foi desenvolvido para simular a variabilidade das linhas de emissão em sistemas binários, além da presença de vento. O código foi utilizado para quantificar os parâmetros necessários para um estudo adequado de tomografia do flickering, tais como número de espectros, relação sinal-ruído destes, e frequência e amplitude do flickering em questão. Três sistemas são abordados: V3885 Sgr, RR Pic e V841 Oph. A variabilidade intrínseca de V3885 Sgr é mapeada através da técnica de tomografia do flickering. O flickering foi simulado e verificou-se que a fonte principal de flickering observada em V3885 Sgr não poderia se originar em um disco de acresção Kepleriano, mas sim na face iluminada da estrela secundária. Uma interpretação proposta para este fenômeno seria de um cenário onde o flickering no contínuo UV originado nas regiões centrais do disco ou na mancha quente é reprocessado na face iluminada da secundária. Obtivemos a primeira confirmação, para uma Variável Cataclísmica de curto período (RR Pic), de uma secundária com relação massa/raio distante da sequência principal. No caso de V841 Oph determinamos o período orbital e obtivemos uma razão de massas um pouco inferior a 1. Verificamos a existência de uma região de emissão mais intensa localizada no quadrante oposto ao esperado para a mancha quente, sendo esta região particularmente brilhante em HeI. O disco de acresção de V841 Oph foi verificado como sendo de baixa emissividade em linhas.An observational study of accretion disks in Cataclysmic Variables (CVs) is presented in this work. Time-resolved spectrophotometric data of the emission line profiles are analyzed. The line emissivity of the systems is mapped using the Doppler tomography technique. The basic orbital parameters of the systems, like the orbital period, mass, orbital inclination, are determined when needed. A code was developed to simulate the emission line profile variability in binary systems, also including the presence of a wind. Such a code was used to quantify the parameters involved in a flickering tomography study, like the number of spectra, signal-to-noise ratio, frequency and amplitude of the flickering. Three systems are analyzed: V3885 Sgr, RR Pic and V841 Oph. The intrinsic variability in V3885 Sgr is mapped using the flickering tomography technique. The flickering was simulated and we have verified that the main flickering source in V3885 Sgr could not be located on the Keplerian accretion disk. The inner face of the secondary star is proposed instead. One interpretation of this phenomenon is a scenery where flickering in the UV continuum from the inner parts of the accretion disk is reprocessed at the illuminated face of the secondary star. The first confirmation of a secondary star with a mass-radius relation far from the main sequence values was obtained for a CV with a short period (RR Pic). In the case of V841 Oph we determined the orbital period and obtained a mass-ratio slightly below 1. We verified the presence of a region of enhanced emission in the quadrant opposite to the one expected for the hot spot. The emission of this region is particularly enhanced in HeI. The V841 Oph accretion disk was verified as being of low emissivity in lines

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data