Fatima Rubio da Costa

DATA-DRIVEN RADIATIVE HYDRODYNAMIC MODELING OF THE 2014 MARCH 29 X1.0 SOLAR FLARE

Spectroscopic observations of solar flares provide critical diagnostics of the physical conditions in the flaring atmosphere. Some key features in observed spectra have not yet been accounted for in existing flare models. Here we report a data-driven simulation of the well-observed X1.0 flare on 2014 March 29 that can reconcile some well-known spectral discrepancies. We analyzed spectra of the flaring region from the Interface Region Imaging Spectrograph (IRIS) in MgII h&k, the Interferometric BIdimensional Spectropolarimeter at the Dunn Solar Telescope (DST/IBIS) in H

Solar Flare Chromospheric Line Emission: Comparison Between IBIS High-resolution Observations and Radiative Hydrodynamic Simulations

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FIRST DETECTION OF > 100 MEV GAMMA RAYS ASSOCIATED WITH A BEHIND-THE-LIMB SOLAR FLARE

6563 \AA\ and CaII 8542 \AA, and the Reuven Ramaty High Energy Solar Spectroscope Imager (RHESSI) in hard X-rays. We constructed a multi-threaded flare loop model and used the electron flux inferred from RHESSI data as the input to the radiative hydrodynamic code RADYN to simulate the atmospheric response. We then synthesized various chromospheric emission lines and compared them with the IRIS and IBIS observations. In general, the synthetic intensities agree with the observed ones, especially near the northern footpoint of the flare. The simulated MgII line profile has narrower wings than the observed one. This discrepancy can be reduced by using a higher microturbulent velocity (27 km/s) in a narrow chromospheric layer. In addition, we found that an increase of electron density in the upper chromosphere within a narrow height range of

A Parameter Study for Modeling Mg ii h and k Emission during Solar Flares

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Hard X-Ray Emission from Partially Occulted Solar Flares: RHESSI Observations in Two Solar Cycles

800 km below the transition region can turn the simulated MgII line core into emission and thus reproduce the single peaked profile, which is a common feature in all IRIS flares.

Hard X-ray morphology of the X1.3 April 25, 2014 partially occulted limb solar flare

Solar flares involve impulsive energy release, which results in enhanced radiation over a broad spectral range and a wide range of heights. In particular, line emission from the chromosphere can provide critical diagnostics of plasma heating processes. Thus, a direct comparison between high-resolution spectroscopic observations and advanced numerical modeling results could be extremely valuable, but has not yet been attempted. In this paper, we present in this paper such a self-consistent investigation of an M3.0 flare observed by the Dunn Solar Telescopes Interferometric Bi-dimensional Spectrometer (IBIS) on 2011 September 24 which we have modeled with the radiative hydrodynamic code RADYN. We obtained images and spectra of the flaring region with IBIS in H

Fermi Large Area Telescope observation of high-energy solar flares: constraining emission scenarios

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Combined Modeling of Acceleration, Transport, and Hydrodynamic Response in Solar Flares. II. Inclusion of Radiative Transfer with RADYN

6563 \AA\ and Ca II 8542 \AA, and with the Reuven Ramaty High Energy Solar Spectroscope Imager (RHESSI) in X-rays. The latter observations were used to infer the non-thermal electron population, which was passed to RADYN to simulate the atmospheric response to electron collisional heating. We then synthesized spectral lines and compared their shapes and intensities to those observed by IBIS and found a general agreement. In particular, the synthetic Ca II 8542 \AA\ profile fits well to the observed profile, while the synthetic H

Fermi Large Area Telescope observations of high-energy gamma-ray emission from behind-the-limb solar flares

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Data-driven Simulations of Magnetic Connectivity in Behind-the-Limb

profile is fainter in the core than for the observation. This indicates that H