TY - JOUR
T1 - Analysis of the impulsive phase of a solar flare at submillimeter wavelengths
AU - Raulin, Jean Pierre
AU - Makhmutov, Vladimir S.
AU - Kaufmann, Pierre
AU - Pacini, Alessandra Abe
AU - Lüthi, Thomas
AU - Hudson, Hugh S.
AU - Gary, Dale
N1 - Funding Information:
This research was partially supported by Brazilian agencies FAPESP (contracts 99/06126-7 and 01/00604-6), CNPq (contracts 300782/96-9 and 304822/89-2) and the Swiss National Science Foundation (Grant 200020-100167). HH would like to acknowledge grant NAS 5-98033. We are grateful for the support of CASLEO engineers and technicians at the observatory of El Leoncito. We thank Dr Nicole Vilmer for stimulating discussions and comments. We also thank Dr Andreas Ma-gun for checking the 89.4 GHz data against any atmospheric effect. The Yohkoh mission of ISAS was prepared and operated by an international collaboration of Japanese, US and UK scientists. We thank M. Yoshimori for the use of Yohkoh/GRS time profiles. OVSA is supported by NSF grant AST-0307670 to New Jersey Institute of Technology.
PY - 2004/11
Y1 - 2004/11
N2 - We present a report on the strong X5.3 solar flare which occurred on 25 August 2001, producing high-level γ-ray activity, nuclear lines and a dramatic long-duration white-light continuum. The bulk of millimeter radio fluxes reached a peak of ∼100 000 solar flux units at 89.4 GHz, and a few thousands of solar flux units were detected in the submillimeter range during the impulsive phase. In this paper we focus on and discuss (i) the implications inferred from high frequency radio observations during the impulsive phase; (ii) the dynamics of the low corona active region during the impulsive phase. In particular we found that 4-5 × 1036 accelerated (>20 keV) electrons s-1 radiating in a 1000-1100 G region, are needed to explain the millimeter to submillimeter-wave emissions. We present evidence that the magnetic field in the active region was very dynamic, and that strong non-thermal processes were triggered by the appearance of new, compact, low-lying (few thousand kilometers) loop systems, suggesting the acceleration site(s) were also located in the low solar atmosphere.
AB - We present a report on the strong X5.3 solar flare which occurred on 25 August 2001, producing high-level γ-ray activity, nuclear lines and a dramatic long-duration white-light continuum. The bulk of millimeter radio fluxes reached a peak of ∼100 000 solar flux units at 89.4 GHz, and a few thousands of solar flux units were detected in the submillimeter range during the impulsive phase. In this paper we focus on and discuss (i) the implications inferred from high frequency radio observations during the impulsive phase; (ii) the dynamics of the low corona active region during the impulsive phase. In particular we found that 4-5 × 1036 accelerated (>20 keV) electrons s-1 radiating in a 1000-1100 G region, are needed to explain the millimeter to submillimeter-wave emissions. We present evidence that the magnetic field in the active region was very dynamic, and that strong non-thermal processes were triggered by the appearance of new, compact, low-lying (few thousand kilometers) loop systems, suggesting the acceleration site(s) were also located in the low solar atmosphere.
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U2 - 10.1007/s11207-004-1300-y
DO - 10.1007/s11207-004-1300-y
M3 - Article
AN - SCOPUS:15444377783
SN - 0038-0938
VL - 223
SP - 181
EP - 199
JO - Solar Physics
JF - Solar Physics
IS - 1-2
ER -