Modelling line emission of deuterated H_3^+ from prestellar cores

Context: The depletion of heavy elements in cold cores of interstellar molecular clouds can lead to a situation where deuterated forms of H_3^+ are the most useful spectroscopic probes of the physical conditions. Aims: The aim is to predict the observability of the rotational lines of H_2D^+ and D_2H^+ from prestellar cores. Methods: Recently derived rate coefficients for the H_3^+ + H_2 isotopic system were applied to the "complete depletion" reaction scheme to calculate abundance profiles in hydrostatic core models. The ground-state lines of H_2D^+(o) (372 GHz) and D_2H^+(p) (692 GHz) arising from these cores were simulated. The excitation of the rotational levels of these molecules was approximated by using the state-to-state coefficients for collisions with H_2. We also predicted line profiles from cores with a power-law density distribution advocated in some previous studies. Results: The new rate coefficients introduce some changes to the complete depletion model, but do not alter the general tendencies. One of the modifications with respect to the previous results is the increase of the D_3^+ abundance at the cost of other isotopologues. Furthermore, the present model predicts a lower H_2D^+ (o/p) ratio, and a slightly higher D_2H^+ (p/o) ratio in very cold, dense cores, as compared with previous modelling results. These nuclear spin ratios affect the detectability of the submm lines of H_2D^+(o) and D_2H^+(p). The previously detected H_2D^+ and D_2H^+ lines towards the core I16293E, and the H_2D^+ line observed towards Oph D can be reproduced using the present excitation model and the physical models suggested in the original papers.Comment: 10 pages, 11 Figures; ver2: updated some of the Figures, added some references, added an entry to acknowledgement

Rotating Shadowband Spectroradiometer (RSS) Handbook

The rotating shawdowband spectroradiometer (RSS) implements the same automated shadowbanding technique used by the multifilter rotating shadowband radiometer (MFRSR), and so it too provides spectrally-resolved, direct-normal, diffuse-horizontal, and total-horizontal irradiances, and can be calibrated in situ via Langley regression. The irradiance spectra are measured simultaneously at all spectral elements (pixels) in 360-nm to 1050-nm range

Photodesorption of CO ice

At the high densities and low temperatures found in star forming regions, all molecules other than H2 should stick on dust grains on timescales shorter than the cloud lifetimes. Yet these clouds are detected in the millimeter lines of gaseous CO. At these temperatures, thermal desorption is negligible and hence a non-thermal desorption mechanism is necessary to maintain molecules in the gas phase. Here, the first laboratory study of the photodesorption of pure CO ice under ultra high vacuum is presented, which gives a desorption rate of 3E-3 CO molecules per UV (7-10.5 eV) photon at 15 K. This rate is factors of 1E2-1E5 larger than previously estimated and is comparable to estimates of other non-thermal desorption rates. The experiments constrains the mechanism to a single photon desorption process of ice surface molecules. The measured efficiency of this process shows that the role of CO photodesorption in preventing total removal of molecules in the gas has been underestimated.Comment: 5 pages, 4 figures, accepted by ApJ

The CDMS view on molecular data needs of Herschel, SOFIA, and ALMA

The catalog section of the Cologne Database for Molecular Spectroscopy, CDMS, contains mostly rotational transition frequencies, with auxiliary information, of molecules observable in space. The frequency lists are generated mostly from critically evaluated laboratory data employing established Hamiltonian models. The CDMS has been online publicly for more than 12 years, e.g., via the short-cut http://www.cdms.de. Initially constructed as ascii tables, its inclusion into a database environment within the Virtual Atomic and Molecular Data Centre (VAMDC, http://www.vamdc.eu) has begun in June 2008. A test version of the new CDMS is about to be released. The CDMS activities have been part of the extensive laboratory spectroscopic investigations in Cologne. Moreover, these activities have also benefit from collaborations with other laboratory spectroscopy groups as well as with astronomers. We will provide some basic information on the CDMS and its participation in the VAMDC project. In addition, some recent detections of molecules as well as spectroscopic studies will be discussed to evaluate the spectroscopic data needs of Herschel, SOFIA, and ALMA in particular in terms of light hydrides, complex molecules, and metal containing speciesComment: 14 pages, 1 figure; AIP Conf. Proc., accepted; Proceedings of the Eighths International Conference on Atomic and Molecular Data and Their Applicatio

Stricto sensu post-graduate modality in discussion: from distance learning models to innovation ecosystems in a hybrid and multimodal context

O artigo, discute os modelos de EaD e, a partir da portaria MEC/CAPES No 275/2018, problematiza a modalidade da pós-graduação stricto sensu, na relação com o contexto híbrido e multimodal. O objetivo é compreender como a cultura híbrida e multimodal contribui para pensar a modalidade da pós-graduação stricto sensu, enquanto ecossistemas de inovação, tendo como pressuposto a epistemologia reticular, conectiva e atópica, fundamentada em Di Felice. A pesquisa qualitativa, exploratória e descritiva, faz uso do método cartográfico de pesquisa-intervenção, proposto por Kastrup para produção e análise de dados. Como resultado principal, apresenta-se a o Ecossistema de Inovação na Educação no contexto híbrido e multimodal, como forma de repensar a modalidade da pós-graduação stricto sensu e sua sustentabilidade. Propõe-se ainda a ressignificação/ampliação da compreensão do lugar dos polos, que passam a ser entendidos enquanto espaços de aprendizagem e articulação com a comunidade/sociedade.The paper discusses the distance learning models and, from the ordinance MEC/CAPES No 275/2018, problematizes the modality of the stricto sensu postgraduation, in the relation with the hybrid and multimodal context. The objective is to understand how the hybrid and multimodal culture contributes to thinking about the modality of the stricto sensu post-graduate, as innovation ecosystems, based on the reticular, connective and atopic, epistemology, proposed by Di Felice. The qualitative, exploratory and descriptive research makes use of the research-intervention cartographic method, proposed by Kastrup for production and data analysis. As a main result, the Ecosystem of Innovation in Education in the hybrid and multimodal context is presented as a way to rethink the modality of the stricto sensu post-graduate course and its sustainability. It is also proposed the re-signification/enlargement of the understanding of the place of the poles, as spaces of learning and articulation with the community/society.info:eu-repo/semantics/publishedVersio

From emergency remote education to HyFlex: a possible way to OnLIFE education?

O Ensino Remoto Emergencial, as Aulas Simultâneas e o Modelo HyFlex representam opções pedagógicas construídas durante a pandemia da Covid-19. Estas propostas situam-se ao nível da solução de problemas, cuja resolução emerge da atenção à vida pragmática, o que implica criatividade. Nesse movimento, um novo nível de atenção é necessário, uma atenção suplementar, o que contribui para a invenção de problemas e onde se potencia a Educação Híbrida e emerge a Educação OnLIFE. O objetivo deste artigo, de natureza eminentemente teórica, último da trilogia “Paradigma de Educação OnLIFE”, é discutir as principais abordagens educacionais desenvolvidas em tempos de pandemia e a emersão de um paradigma educacional em que não exista distinção entre offline e online, e em que as tecnologias digitais e as redes não sejam encaradas como ferramentas, mas como forças ambientais que afetam a nossa autoconceção, as nossas interações e como ensinamos e aprendemos.The Emergency Remote Education, Simultaneous Classes or the HyFlex Model represent pedagogical options built during the Covid-19 pandemic. These proposals are at the level of “problem solving”, in which resolution emerges from attention to pragmatic life, which necessarily requires creativity. In this movement, a new level of attention is needed, the level of inventiveness, which contributes to the invention of problems and where Hybrid Education is enhanced, and OnLIFE Education emerges. The main goal of this article, of an eminently theoretical nature, the last of the “OnLIFE Education Paradigm” trilogy, is to discuss the main educational approaches developed in pandemic times and the emergence of an educational paradigm in which there is no distinction between offline and online and in which digital technologies and networks are not seen as tools, but as environmental forces that affect our self-conception, our interactions and how we teach and learn.info:eu-repo/semantics/publishedVersio