https://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&feed=atom&action=historyUser talk:Jiongqiu - Revision history2024-03-28T22:46:06ZRevision history for this page on the wikiMediaWiki 1.16.0https://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=7512&oldid=prevWikisysop at 16:31, 2 January 20152015-01-02T16:31:07Z<p></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 16:31, 2 January 2015</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 50:</td>
<td colspan="2" class="diff-lineno">Line 50:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>This Nugget is based on two manuscripts [http://adsabs.harvard.edu/abs/2012A%26A...547A..72Q Solar Flare Hard X-ray Spikes Observed by RHESSI: a Case Study] and [http://adsabs.harvard.edu/abs/2012A%26A...547A..73C Solar Flare Hard X-ray Spikes Observed by RHESSI: a Statistical Study] by the author with Jianxia Cheng, Gordon J. Hurford, Haimin Wang, Yan Xu, and Mingde Ding, published in Astronomy and Astrophysics.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>This Nugget is based on two manuscripts [http://adsabs.harvard.edu/abs/2012A%26A...547A..72Q Solar Flare Hard X-ray Spikes Observed by RHESSI: a Case Study] and [http://adsabs.harvard.edu/abs/2012A%26A...547A..73C Solar Flare Hard X-ray Spikes Observed by RHESSI: a Statistical Study] by the author with Jianxia Cheng, Gordon J. Hurford, Haimin Wang, Yan Xu, and Mingde Ding, published in Astronomy and Astrophysics.</div></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del style="color: red; font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del style="color: red; font-weight: bold; text-decoration: none;">[Category: Nugget]]</del></div></td><td colspan="2"> </td></tr>
</table>Wikisysophttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5602&oldid=prevJiongqiu at 22:27, 29 December 20122012-12-29T22:27:50Z<p></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:27, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 18:</td>
<td colspan="2" class="diff-lineno">Line 18:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>RHESSI (Lin et al. , 2002) has provided unprecedented advantage to hopefully answer these questions. This nugget studies a sample of hard X-ray flares observed by RHESS using a demodulation algorithm that allows analysis of hard X-ray light curves with sub-second time resolution. It should be noted that the study focuses on the most prominent fast-varying bursts standing out of, rather than making up, the entire flare emission. We call them "hard X-ray spikes" (Figure1).</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>RHESSI (Lin et al. , 2002) has provided unprecedented advantage to hopefully answer these questions. This nugget studies a sample of hard X-ray flares observed by RHESS using a demodulation algorithm that allows analysis of hard X-ray light curves with sub-second time resolution. It should be noted that the study focuses on the most prominent fast-varying bursts standing out of, rather than making up, the entire flare emission. We call them "hard X-ray spikes" (Figure1).</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig1.jpg|center|thumb|<del class="diffchange diffchange-inline">800px</del>|Figure 1: Examples of two hard X-ray spikes found in a flare event in a range of photon energies from 15 to 300 keV. The hard X-ray light curves are derived after applying the demodulation algorithm with 125ms time grid. ]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig1.jpg|center|thumb|<ins class="diffchange diffchange-inline">700px</ins>|Figure 1: Examples of two hard X-ray spikes found in a flare event in a range of photon energies from 15 to 300 keV. The hard X-ray light curves are derived after applying the demodulation algorithm with 125ms time grid. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Temporal and Spectral Properties of Hard X-ray Spikes ==</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Temporal and Spectral Properties of Hard X-ray Spikes ==</div></td></tr>
<tr><td colspan="2" class="diff-lineno">Line 33:</td>
<td colspan="2" class="diff-lineno">Line 33:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig4.jpg|<del class="diffchange diffchange-inline">left</del>|thumb|400px|Figure 4: UV images from TRACE (top) and hard X-ray maps of 2s integration from RHESSI (bottom contours) before and during the time of a spike. RHESSI maps are superimposed on a longitudinal magnetogram from MDI. Grey curves in all panels indicate the polarity inversion line of magnetic fields. The inset frames on the top panel illustrate the details of the two flare kernels where the spike emission is located.]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig4.jpg|<ins class="diffchange diffchange-inline">right</ins>|thumb|400px|Figure 4: UV images from TRACE (top) and hard X-ray maps of 2s integration from RHESSI (bottom contours) before and during the time of a spike. RHESSI maps are superimposed on a longitudinal magnetogram from MDI. Grey curves in all panels indicate the polarity inversion line of magnetic fields. The inset frames on the top panel illustrate the details of the two flare kernels where the spike emission is located.]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Very short timescales are usually associated with small spatial scales; it has been challenging to map fast-varying structures during the flare. A few different ways have been attempted to locate ten spikes out of the studied sample. Direct mapping of the spikes, as confirmed by coordinated UV and optical images whenever available, shows that the spikes at above 25 keVs are most likely thick-target emissions at conjugate foot-points of flare loops (Figure 4), and observed loop length is consistent with estimate from time-of-flight analysis. </div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Very short timescales are usually associated with small spatial scales; it has been challenging to map fast-varying structures during the flare. A few different ways have been attempted to locate ten spikes out of the studied sample. Direct mapping of the spikes, as confirmed by coordinated UV and optical images whenever available, shows that the spikes at above 25 keVs are most likely thick-target emissions at conjugate foot-points of flare loops (Figure 4), and observed loop length is consistent with estimate from time-of-flight analysis. </div></td></tr>
</table>Jiongqiuhttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5601&oldid=prevJiongqiu: /* Temporal and Spectral Properties of Hard X-ray Spikes */2012-12-29T22:26:07Z<p><span class="autocomment">Temporal and Spectral Properties of Hard X-ray Spikes</span></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:26, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 24:</td>
<td colspan="2" class="diff-lineno">Line 24:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|<del class="diffchange diffchange-inline">570px</del>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|<ins class="diffchange diffchange-inline">555px</ins>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|300px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|300px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
</table>Jiongqiuhttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5600&oldid=prevJiongqiu: /* Temporal and Spectral Properties of Hard X-ray Spikes */2012-12-29T22:25:40Z<p><span class="autocomment">Temporal and Spectral Properties of Hard X-ray Spikes</span></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:25, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 24:</td>
<td colspan="2" class="diff-lineno">Line 24:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|<del class="diffchange diffchange-inline">550px</del>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|<ins class="diffchange diffchange-inline">570px</ins>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|300px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|300px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
</table>Jiongqiuhttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5599&oldid=prevJiongqiu: /* Temporal and Spectral Properties of Hard X-ray Spikes */2012-12-29T22:24:55Z<p><span class="autocomment">Temporal and Spectral Properties of Hard X-ray Spikes</span></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:24, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 24:</td>
<td colspan="2" class="diff-lineno">Line 24:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|<del class="diffchange diffchange-inline">600px</del>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|<ins class="diffchange diffchange-inline">550px</ins>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|300px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|300px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
</table>Jiongqiuhttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5598&oldid=prevJiongqiu: /* Temporal and Spectral Properties of Hard X-ray Spikes */2012-12-29T22:24:22Z<p><span class="autocomment">Temporal and Spectral Properties of Hard X-ray Spikes</span></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:24, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 24:</td>
<td colspan="2" class="diff-lineno">Line 24:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|<del class="diffchange diffchange-inline">500px</del>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|<ins class="diffchange diffchange-inline">600px</ins>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|300px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|300px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
</table>Jiongqiuhttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5597&oldid=prevJiongqiu: /* Temporal and Spectral Properties of Hard X-ray Spikes */2012-12-29T22:23:56Z<p><span class="autocomment">Temporal and Spectral Properties of Hard X-ray Spikes</span></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:23, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 25:</td>
<td colspan="2" class="diff-lineno">Line 25:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|500px|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|left|thumb|500px|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|<del class="diffchange diffchange-inline">200px</del>|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|<ins class="diffchange diffchange-inline">300px</ins>|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>In terms of the spectral property of the spikes, the spectrum of integrated counts at greater than 20 keV can be fitted to a power-law distribution, </div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>In terms of the spectral property of the spikes, the spectrum of integrated counts at greater than 20 keV can be fitted to a power-law distribution, </div></td></tr>
</table>Jiongqiuhttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5596&oldid=prevJiongqiu at 22:22, 29 December 20122012-12-29T22:22:42Z<p></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:22, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 24:</td>
<td colspan="2" class="diff-lineno">Line 24:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Having searched the entire flare catalog in 2002, it turns out that hard X-ray spikes can be detected at up to 100 keV in only a small fraction of flares. The spikes usually have symmetric rise and decay, and have durations below one second, which is independent of the photon energy (Figure 2). These results are consistent with the findings by SMM three decades ago.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|<del class="diffchange diffchange-inline">center</del>|thumb|<del class="diffchange diffchange-inline">600px</del>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|<ins class="diffchange diffchange-inline">left</ins>|thumb|<ins class="diffchange diffchange-inline">500px</ins>|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div> </div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|200px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|200px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td colspan="2" class="diff-lineno">Line 33:</td>
<td colspan="2" class="diff-lineno">Line 32:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Where Are the Spikes? ==</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Where Are the Spikes? ==</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del style="color: red; font-weight: bold; text-decoration: none;">Very short timescales are usually associated with small spatial scales; it has been challenging to map fast-varying structures during the flare. A few different ways have been attempted to locate ten spikes out of the studied sample. Direct mapping of the spikes, as confirmed by coordinated UV and optical images whenever available, shows that the spikes at above 25 keVs are most likely thick-target emissions at conjugate foot-points of flare loops (Figure 4), and observed loop length is consistent with estimate from time-of-flight analysis. </del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig4.jpg|left|thumb|400px|Figure 4: UV images from TRACE (top) and hard X-ray maps of 2s integration from RHESSI (bottom contours) before and during the time of a spike. RHESSI maps are superimposed on a longitudinal magnetogram from MDI. Grey curves in all panels indicate the polarity inversion line of magnetic fields. The inset frames on the top panel illustrate the details of the two flare kernels where the spike emission is located.]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig4.jpg|left|thumb|400px|Figure 4: UV images from TRACE (top) and hard X-ray maps of 2s integration from RHESSI (bottom contours) before and during the time of a spike. RHESSI maps are superimposed on a longitudinal magnetogram from MDI. Grey curves in all panels indicate the polarity inversion line of magnetic fields. The inset frames on the top panel illustrate the details of the two flare kernels where the spike emission is located.]]</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;">Very short timescales are usually associated with small spatial scales; it has been challenging to map fast-varying structures during the flare. A few different ways have been attempted to locate ten spikes out of the studied sample. Direct mapping of the spikes, as confirmed by coordinated UV and optical images whenever available, shows that the spikes at above 25 keVs are most likely thick-target emissions at conjugate foot-points of flare loops (Figure 4), and observed loop length is consistent with estimate from time-of-flight analysis. </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Comparing hard X-ray and UV observations during and immediately before the spikes, we find that the spikes are basically inside or very closely attached to the sources of underlying components. The RHESSI image of 2s integration during the spike shows enhanced emission over the pre-spike source, yet the >4" map resolution does not reveal variations, if any, in the shape or location of the emission source. The better resolved UV images by TRACE (1" resolution) illustrate more clearly that, during the spike, UV emission is enhanced at a few flare kernels of a few arc-seconds, which have been brightened before the spike. These details would</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Comparing hard X-ray and UV observations during and immediately before the spikes, we find that the spikes are basically inside or very closely attached to the sources of underlying components. The RHESSI image of 2s integration during the spike shows enhanced emission over the pre-spike source, yet the >4" map resolution does not reveal variations, if any, in the shape or location of the emission source. The better resolved UV images by TRACE (1" resolution) illustrate more clearly that, during the spike, UV emission is enhanced at a few flare kernels of a few arc-seconds, which have been brightened before the spike. These details would</div></td></tr>
</table>Jiongqiuhttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5595&oldid=prevJiongqiu at 22:18, 29 December 20122012-12-29T22:18:24Z<p></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:18, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 26:</td>
<td colspan="2" class="diff-lineno">Line 26:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|center|thumb|600px|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|center|thumb|600px|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|<del class="diffchange diffchange-inline">400px</del>|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig3.jpg|right|thumb|<ins class="diffchange diffchange-inline">200px</ins>|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>In terms of the spectral property of the spikes, the spectrum of integrated counts at greater than 20 keV can be fitted to a power-law distribution, </div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>In terms of the spectral property of the spikes, the spectrum of integrated counts at greater than 20 keV can be fitted to a power-law distribution, </div></td></tr>
<tr><td colspan="2" class="diff-lineno">Line 35:</td>
<td colspan="2" class="diff-lineno">Line 35:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Very short timescales are usually associated with small spatial scales; it has been challenging to map fast-varying structures during the flare. A few different ways have been attempted to locate ten spikes out of the studied sample. Direct mapping of the spikes, as confirmed by coordinated UV and optical images whenever available, shows that the spikes at above 25 keVs are most likely thick-target emissions at conjugate foot-points of flare loops (Figure 4), and observed loop length is consistent with estimate from time-of-flight analysis. </div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Very short timescales are usually associated with small spatial scales; it has been challenging to map fast-varying structures during the flare. A few different ways have been attempted to locate ten spikes out of the studied sample. Direct mapping of the spikes, as confirmed by coordinated UV and optical images whenever available, shows that the spikes at above 25 keVs are most likely thick-target emissions at conjugate foot-points of flare loops (Figure 4), and observed loop length is consistent with estimate from time-of-flight analysis. </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div>[[Image:qiu_fig4.jpg|<del class="diffchange diffchange-inline">center</del>|thumb|<del class="diffchange diffchange-inline">600px</del>|Figure 4: UV images from TRACE (top) and hard X-ray maps of 2s integration from RHESSI (bottom contours) before and during the time of a spike. RHESSI maps are superimposed on a longitudinal magnetogram from MDI. Grey curves in all panels indicate the polarity inversion line of magnetic fields. The inset frames on the top panel illustrate the details of the two flare kernels where the spike emission is located.]]</div></td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div>[[Image:qiu_fig4.jpg|<ins class="diffchange diffchange-inline">left</ins>|thumb|<ins class="diffchange diffchange-inline">400px</ins>|Figure 4: UV images from TRACE (top) and hard X-ray maps of 2s integration from RHESSI (bottom contours) before and during the time of a spike. RHESSI maps are superimposed on a longitudinal magnetogram from MDI. Grey curves in all panels indicate the polarity inversion line of magnetic fields. The inset frames on the top panel illustrate the details of the two flare kernels where the spike emission is located.]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Comparing hard X-ray and UV observations during and immediately before the spikes, we find that the spikes are basically inside or very closely attached to the sources of underlying components. The RHESSI image of 2s integration during the spike shows enhanced emission over the pre-spike source, yet the >4" map resolution does not reveal variations, if any, in the shape or location of the emission source. The better resolved UV images by TRACE (1" resolution) illustrate more clearly that, during the spike, UV emission is enhanced at a few flare kernels of a few arc-seconds, which have been brightened before the spike. These details would</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>Comparing hard X-ray and UV observations during and immediately before the spikes, we find that the spikes are basically inside or very closely attached to the sources of underlying components. The RHESSI image of 2s integration during the spike shows enhanced emission over the pre-spike source, yet the >4" map resolution does not reveal variations, if any, in the shape or location of the emission source. The better resolved UV images by TRACE (1" resolution) illustrate more clearly that, during the spike, UV emission is enhanced at a few flare kernels of a few arc-seconds, which have been brightened before the spike. These details would</div></td></tr>
</table>Jiongqiuhttps://sprg.ssl.berkeley.edu/~tohban/wiki/index.php?title=User_talk:Jiongqiu&diff=5594&oldid=prevJiongqiu: /* Temporal and Spectral Properties of Hard X-ray Spikes */2012-12-29T22:17:01Z<p><span class="autocomment">Temporal and Spectral Properties of Hard X-ray Spikes</span></p>
<table style="background-color: white; color:black;">
<col class='diff-marker' />
<col class='diff-content' />
<col class='diff-marker' />
<col class='diff-content' />
<tr valign='top'>
<td colspan='2' style="background-color: white; color:black;">← Older revision</td>
<td colspan='2' style="background-color: white; color:black;">Revision as of 22:17, 29 December 2012</td>
</tr><tr><td colspan="2" class="diff-lineno">Line 25:</td>
<td colspan="2" class="diff-lineno">Line 25:</td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|center|thumb|600px|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>[[Image:qiu_fig2.jpg|center|thumb|600px|Figure 2: temporal properties of two example hard X-ray spikes. Left: duration of spikes at different energies. Right: energy-dependent spike peak times (symbol) fitted to the time-of-flight plot (lines). ]]</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="background: #cfc; color:black; font-size: smaller;"><div><ins style="color: red; font-weight: bold; text-decoration: none;">[[Image:qiu_fig3.jpg|right|thumb|400px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>In terms of the spectral property of the spikes, the spectrum of integrated counts at greater than 20 keV can be fitted to a power-law distribution, </div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>In terms of the spectral property of the spikes, the spectrum of integrated counts at greater than 20 keV can be fitted to a power-law distribution, </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>a generally recognized signature of non-thermal emission. Compared with underlying components, spikes have slightly harder spectrum (Figure 3). A fraction of the spikes also exhibit energy-dependent time lag of either kind: the low-energy emission lagging high-energy emission, usually interpreted as reflecting time-of-flight of direct precipitation electrons, or high-energy emission lagging low-energy emission that is thought to be indicative of Coulomb collision effects in the trap.</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>a generally recognized signature of non-thermal emission. Compared with underlying components, spikes have slightly harder spectrum (Figure 3). A fraction of the spikes also exhibit energy-dependent time lag of either kind: the low-energy emission lagging high-energy emission, usually interpreted as reflecting time-of-flight of direct precipitation electrons, or high-energy emission lagging low-energy emission that is thought to be indicative of Coulomb collision effects in the trap.</div></td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del style="color: red; font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>-</td><td style="background: #ffa; color:black; font-size: smaller;"><div><del style="color: red; font-weight: bold; text-decoration: none;">[[Image:qiu_fig3.jpg|right|thumb|400px|Figure 3: counts spectral indices of the spikes versus those of the underlying components. ]]</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Where Are the Spikes? ==</div></td><td class='diff-marker'> </td><td style="background: #eee; color:black; font-size: smaller;"><div>== Where Are the Spikes? ==</div></td></tr>
</table>Jiongqiu