Search Results - "Longcope, Dana"

LONG DURATION FLARE EMISSION: IMPULSIVE HEATING OR GRADUAL HEATING? by Qiu, Jiong, Longcope, Dana W.

“…ABSTRACT Flare emissions in X-ray and EUV wavelengths have previously been modeled as the plasma response to impulsive heating from magnetic reconnection. Some…”
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Two-phase Heating in Flaring Loops by Zhu, Chunming, Qiu, Jiong, Longcope, Dana W.

“…We analyze and model a C5.7 two-ribbon solar flare observed by the Solar Dynamics Observatory, Hinode, and GOES on 2011 December 26. The flare is made of many…”
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A Model for Gradual-phase Heating Driven by MHD Turbulence in Solar Flares by Ashfield, William, Longcope, Dana

“…Coronal flare emission is commonly observed to decay on timescales longer than those predicted by impulsively driven, one-dimensional flare loop models. This…”
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Elongation of Flare Ribbons by Qiu, Jiong, Longcope, Dana W., Cassak, Paul A., Priest, Eric R.

“…We present an analysis of the apparent elongation motion of flare ribbons along the polarity inversion line (PIL), as well as the shear of flare loops in…”
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Multispacecraft Observations of Coronal Loops to Verify a Force-free Field Reconstruction and Infer Loop Cross Sections by McCarthy, Marika I., Longcope, Dana W., Malanushenko, Anna

“…Active region EUV loops are believed to trace a subset of magnetic field lines through the corona. Malanushenko et al. proposed a method, using loop images and…”
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Localized Reconnection Heating Inferred from the Three-dimensional Locations of Bright Active Region Coronal Loops by Longcope, Dana, McCarthy, Marika, Malanushenko, Anna

“…Coronal loops observed in soft X-rays and extreme ultraviolet imaging data offer direct evidence that coronal plasma is heated by some mechanism. That…”
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Connecting Chromospheric Condensation Signatures to Reconnection-driven Heating Rates in an Observed Flare by Ashfield IV, William H., Longcope, Dana W., Zhu, Chunming, Qiu, Jiong

“…Observations of solar flare reconnection at very high spatial and temporal resolution can be made indirectly at the footpoints of reconnected loops into which…”
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A RECONNECTION-DRIVEN MODEL OF THE HARD X-RAY LOOP-TOP SOURCE FROM FLARE 2004 FEBRUARY 26 by Longcope, Dana, Qiu, Jiong, Brewer, Jasmine

“…ABSTRACT A compact X-class flare on 2004 February 26 showed a concentrated source of hard X-rays at the tops of the flare's loops. This was analyzed in…”
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RECONNECTION OUTFLOWS AND CURRENT SHEET OBSERVED WITH HINODE/XRT IN THE 2008 APRIL 9 CARTWHEEL CME FLARE by SAVAGE, Sabrina L, MCKENZIE, David E, REEVES, Katharine K, FORBES, Terry G, LONGCOPE, Dana W

“…Supra-arcade downflows (SADs) have been observed with Yohkoh/SXT (soft X-rays (SXR)), TRACE (extreme ultraviolet (EUV)), SOHO/LASCO (white light), SOHO/SUMER…”
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HEATING OF FLARE LOOPS WITH OBSERVATIONALLY CONSTRAINED HEATING FUNCTIONS by JIONG QIU, LIU, Wen-Juan, LONGCOPE, Dana W

“…We analyze high-cadence high-resolution observations of a C3.2 flare obtained by AIA/SDO on 2010 August 1. The flare is a long-duration event with soft X-ray…”
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Observationally quantified reconnection providing a viable mechanism for active region coronal heating by Yang, Kai E., Longcope, Dana W., Ding, M. D., Guo, Yang

“…The heating of the Sun’s corona has been explained by several different mechanisms including wave dissipation and magnetic reconnection. While both have been…”
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DETERMINING HEATING RATES IN RECONNECTION FORMED FLARE LOOPS OF THE M8.0 FLARE ON 2005 MAY 13 by Liu, Wen-Juan, Qiu, Jiong, Longcope, Dana W, Caspi, Amir

“…We analyze and model an M8.0 flare on 2005 May 13 observed by the Transition Region and Coronal Explorer and the Reuven Ramaty High Energy Solar Spectroscopic…”
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Measuring and Modeling the Rate of Separator Reconnection between an Emerging and an Existing Active Region by McCarthy, Marika I., Longcope, Dana W., Malanushenko, Anna, McKenzie, David E.

“…Magnetic reconnection occurs when new flux emerges into the corona and becomes incorporated into the existing coronal field. A new active region (AR) emerging…”
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SMALL-SCALE AND GLOBAL DYNAMOS AND THE AREA AND FLUX DISTRIBUTIONS OF ACTIVE REGIONS, SUNSPOT GROUPS, AND SUNSPOTS: A MULTI-DATABASE STUDY by Munoz-Jaramillo, Andres, Senkpeil, Ryan R, Windmueller, John C, Amouzou, Ernest C, Longcope, Dana W, Tlatov, Andrey G, Nagovitsyn, Yury A, Pevtsov, Alexei A, Chapman, Gary A, Cookson, Angela M, Yeates, Anthony R, Watson, Fraser T, Balmaceda, Laura A, DeLuca, Edward E, Martens, Petrus C H

“…In this work, we take advantage of 11 different sunspot group, sunspot, and active region databases to characterize the area and flux distributions of…”
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INFERRING THE MAGNETOHYDRODYNAMIC STRUCTURE OF SOLAR FLARE SUPRA-ARCADE PLASMAS FROM A DATA-ASSIMILATED FIELD TRANSPORT MODEL by Scott, Roger B., McKenzie, David E., Longcope, Dana W.

“…ABSTRACT Supra-arcade fans are highly dynamic structures that form in the region above post-reconnection flare arcades. In these features the plasma density…”
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NUMERICAL SIMULATIONS OF PLASMA DYNAMICS IN THE VICINITY OF A RETRACTING FLUX TUBE by Scott, Roger B., Longcope, Dana W., McKenzie, David E.

“…ABSTRACT In a previous paper, we presented an analytical, zero-β model for supra-arcade downflows in which a retracting flux tube deforms the surrounding…”
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ULTRAVIOLET AND EXTREME-ULTRAVIOLET EMISSIONS AT THE FLARE FOOTPOINTS OBSERVED BY ATMOSPHERE IMAGING ASSEMBLY by Qiu, Jiong, Sturrock, Zoe, Longcope, Dana W, Klimchuk, James A, Liu, Wen-Juan

“…A solar flare is composed of impulsive energy release events by magnetic reconnection, which forms and heats flare loops. Recent studies have revealed a…”
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PERISTALTIC PUMPING NEAR POST-CORONAL MASS EJECTION SUPRA-ARCADE CURRENT SHEETS by Scott, Roger B, Longcope, Dana W, McKenzie, David E

“…Temperature and density measurements near supra-arcade current sheets suggest that plasma on unreconnected field lines may experience some degree of…”
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Topological Methods for the Analysis of Solar Magnetic Fields by Longcope, Dana W.

“…The solar coronal magnetic field is anchored to a complex distribution of photospheric flux consisting of sunspots and magnetic elements. Coronal activity such…”
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Quiescent Reconnection Rate Between Emerging Active Regions and Preexisting Field, with Associated Heating: NOAA AR 11112 by Tarr, Lucas A., Longcope, Dana W., McKenzie, David E., Yoshimura, Keiji

“…When magnetic flux emerges from beneath the photosphere, it displaces the preexisting field in the corona, and a current sheet generally forms at the boundary…”
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