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tokens: of [2] and [3], which show FERMI spectra because they provided better statistics. We note that the corresponding RHESSI spectra at those times showed very similar results. The X-ray spectra of background-subtracted data (black solid lines) are plotted together with the fitting results for the isothermal component (red dashed lines), and the nonthermal component (blue dashed lines). The background is represented by the gray solid line. The electron temperature, T , emission measure, EM, electron distribution index, δ , and cutoff energy, E C , as well as the chi-squared of the fitting, χ 2 , are listed. Figure 4. (a)–(d) EM-weighted temperature maps during the M1.3 flare. The dotted lines represent an artificial slit along the trajectory of the jet-like feature, along which we extracted the DEM evolution. (e) Time–distance plot for EM-weighted temperatures along the slit. (f) EM distribution for the position and times marked by the colored circles in panel (e). An animation of panels (a)–(d) is available. The video begins at 21:30:01 and ends at 22:14:49. The realtime duration of the animation is 15 s. (An animation of this figure is available.) In order to infer information on the triggering of the event and its magnetic topology, we initially studied the magnetic field of AR 11944 during the flare under study as well as a few days before. We note that due to the rapidly varying photospheric magnetic field of the AR prior to the occurrence of SOL2014-01-13T21:51M1.3, its closeness to the limb, and the small-scale nature of the event, the magnetograms did not provide us with useful information for the magnetic configuration on the date of the flare occurrence. 3.3. Causal Relationship of Precursors and Flare Features In addition to the bright loop and associated chromospheric brightenings observed for P2 and P3, the impulsive flare phase starts with the appearance of an additional loop (marked by the orange dashed line in the inset of Figure 2 (d)) rooted at a chromospheric brightening (labeled (3)). This was immediately followed by the generation of flare ribbons neighboring L1 and the enhanced emission at L2 as a consequence of nonthermal bremsstrahlung (Figure 2 (e)). No X-ray sources were found at the locations where the ribbons formed encompassing L1 (Figures 3 (d), (e)), possibly due to RHESSI ’s limited dynamic range. However, strong nonthermal emission during the impulsive flare phase was registered at L2, in the form of a compact hard x-ray (HXR) source and a flat nonthermal ( δ ∼ 4.2) component in the corresponding spectrum (Figure 3 (d)). This shows that L2 was the main compact flare region. During this phase, a jet-like feature emerged from L2 (see inset in Figure 2 (e) and Figures 4 (d), (e)), reaching its maximum altitude at . The EM distribution of a position along the jet-like feature before, during and after its occurrence is shown in Figure 4 (f) (see position and corresponding times marked in Figure 4 (e)), showing that it