Estimation of a coronal mass ejection magnetic field strength using radio observations of gyrosynchrotron radiation

Coronal mass ejections (CMEs) are large eruptions of plasma and magnetic field from the low solar corona into interplanetary space. These eruptions are often associated with the acceleration of energetic electrons which produce various sources of high intensity plasma emission. In relatively rare cases, the energetic electrons may also produce gyrosynchrotron emission from within the CME itself, allowing for a diagnostic of the CME magnetic field strength. Such a magnetic field diagnostic is important for evaluating the total magnetic energy content of the CME, which is ultimately what drives the eruption. Here, we report on an unusually large source of gyrosynchrotron radiation in the form of a type IV radio burst associated with a CME occurring on 2014-September-01, observed using instrumentation from the Nançay Radio Astronomy Facility. A combination of spectral flux density measurements from the Nançay instruments and the Radio Solar Telescope Network (RSTN) from 300 MHz to 5 GHz reveals a gyrosynchrotron spectrum with a peak flux density at ∼1 GHz. Using this radio analysis, a model for gyrosynchrotron radiation, a non-thermal electron density diagnostic using the Fermi Gamma Ray Burst Monitor (GBM) and images of the eruption from the GOES Soft X-ray Imager (SXI), we were able to calculate both the magnetic field strength and the properties of the X-ray and radio emitting energetic electrons within the CME. We find the radio emission is produced by non-thermal electrons of energies >1 MeV with a spectral index of δ ∼ 3 in a CME magnetic field of 4.4 G at a height of 1.3 R�, while the X-ray emission is produced from a similar distribution of electrons but with much lower energies on the order of 10 keV. We conclude by comparing the electron distribution characteristics derived from both X-ray and radio and show how such an analysis can be used to define the plasma and bulk properties of a CME

Transition region and chromospheric signatures of impulsive heating events. II. Modeling

Results from the Solar Maximum Mission showed a close connection between the hard X-ray (HXR) and transition region (TR) emission in solar flares. Analogously, the modern combination of RHESSI and IRIS data can inform the details of heating processes in ways that were never before possible. We study a small event that was observed with RHESSI, IRIS, SDO, and Hinode, allowing us to strongly constrain the heating and hydrodynamical properties of the flare, with detailed observations presented in a previous paper. Long duration redshifts of TR lines observed in this event, as well as many other events, are fundamentally incompatible with chromospheric condensation on a single loop. We combine RHESSI and IRIS data to measure the energy partition among the many magnetic strands that comprise the flare. Using that observationally determined energy partition, we show that a proper multithreaded model can reproduce these redshifts in magnitude, duration, and line intensity, while simultaneously being well constrained by the observed density, temperature, and emission measure. We comment on the implications for both RHESSI and IRIS observations of flares in general, namely that: (1) a single loop model is inconsistent with long duration redshifts, among other observables; (2) the average time between energization of strands is less than 10 s, which implies that for a HXR burst lasting 10 minutes, there were at least 60 strands within a single IRIS pixel located on the flare ribbon; (3) the majority of these strands were explosively heated with an energy distribution well described by a power law of slope »-1.6; (4) the multi-stranded model reproduces the observed line profiles, peak temperatures, differential emission measure distributions, and densities

Phyladelphia positive acute lymphoblastic leukemia

O cromossomo Filadélfia (Ph1) é a alteração citogenética mais comum da Leucemia Linfoblástica Aguda do adulto (LLA). Esta alteração citogenética predomina nos adultos com mais de 50 anos e na LLA de origem na célula B, principalmente CD10 positiva. O diagnóstico requer a análise citogenética e a pesquisa do mRNA do gene BCR-ABL no sangue periférico ou na medula óssea. A LLA Ph1 apresenta uma sobrevida global em cinco anos inferior a 20% quando tratada com protocolos para LLA. Os poucos casos de cura ocorrem nos pacientes submetidos ao transplante alogênico de medula óssea (TMO). A adição do imatinibe à quimioterapia resultou em melhora na taxa de remissão completa, maior taxa de remissão molecular completa, maior número de pacientes aptos para realizar o TMO, uma maior sobrevida livre de eventos e maior sobrevida global, embora o tempo de seguimento seja ainda muito curto. Entretanto, a taxa de recaídas e o aparecimento de mutações do BCR-ABL resistentes ao imatinibe ainda são preocupantes. No futuro, novos inibidores de tirosina quinase poderão ser incorporados ao tratamento da LLA Ph1.The Philadelphia chromosome (Ph1) is the most frequent abnormality in acute adult lymphoblastic leukemia (ALL). Ph1 positive ALL is more frequent in over 50-year-old adults, in B-cell ALL and CD10-positive ALL. Diagnosis is based on the identification of the BCR-ABL gene mRNA in peripheral blood or bone marrow. The 5-year overall survival of patients with Ph1 positive ALL treated with chemotherapy alone is less than 20%. A few cases may be cured by allogeneic stem cell transplantation. The addition of imatinib to the chemotherapeutic treatment has resulted in more complete remissions, more complete molecular responses, more patients able to perform stem cell transplantation, better event-free survival and better overall survival, although the study follow-up period is very short so far. High relapse rates and the emergence of BCR-ABL mutants resistant to imatinib are still significant. In the future, newer tyrosine-kinase inhibitors may be added to the chemotherapy

Análise comparativa da quantificação da acção da neve de acordo com o RSA, a norma espanhola NBE e o EC1

A quantificação da acção da neve de acordo com a regulamentação em vigor em Portugal, Espanha e com o estabelecido no Eurocódigo 1 fornece resultados muito distintos. Neste trabalho é realizada uma análise comparativa entre o método de cálculo indicado pelo Regulamento de Segurança e Acções para Estruturas de Edifícios e Pontes, a norma espanhola NBE e o Eurocódigo 1. Foram analisados e comparados os vários parâmetros intervenientes na quantificação da acção da neve

Sustainable Offshore Wind Potential in Continental Portugal

This study intends to depict the availability of the sustainable offshore wind energy for Continental Portugal and identify the preliminary areas for developing offshore wind parks. Two scenarios were performed to distinct the different offshore wind turbine prototypes assembled by the manufactory energy sector – bottom fixed and floating models. The results achieved until now indicate that Portugal has a very large potential for offshore wind deployments ready to be exploited, especially for deep offshore solutions

Chronology of granitic structures in variscan "folded" granite associated to a shear zone (NW PORTUGAL)

Poster apresentado no 32nd International Geological Congress, Florença, Itália, 20-28 Agosto 2004

Úlcera Digital Atípica Causada por HSV-2

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