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We present a detailed analysis of the long-duration GRB 241030A detected by Swift. Thanks to the rapid response of the X-Ray Telescope (XRT) and Ultraviolet/Optical Telescope, the strongest part of the prompt emission of GRB 241030A has been well measured simultaneously from the optical to hard X-ray bands. The time-resolved WHITE band emission shows strong variability, largely tracing the activity of the prompt γ-ray emission, suggesting that it may also be produced by internal shocks too. The joint analysis of the XRT and Burst Alert Telescope data reveals the presence of a thermal component with a temperature of a few keV, which can be interpreted as the photosphere radiation, and the upper limit of the Lorentz factor of this region is found to range between approximately 20 and 80. The time-resolved analysis of the initial U-band exposure data yields a very rapid rise (∼t5.3) with a bright peak reaching 13.6 AB magnitude around 410 s, which is most likely attributed to the onset of the external shock emission. The richness and fineness of early observational data have made this burst unique for studying various radiation mechanisms of γ-ray bursts.

We present the discovery of a peculiar X-ray transient, EP241021a, by the Einstein Probe (EP) mission, and the results from multiwavelength follow-up observations. The transient was first detected with the Wide-field X-ray Telescope as an intense flare lasting for ~100 s, reaching a luminosity of L_(0.5-4 keV)~10^48 erg/s at z=0.748. Further observations with EP's Follow-up X-ray Telescope reveal a huge drop in the X-ray flux by a factor of >1000 within 1.5 days. After maintaining a nearly plateau phase for ~7 days, the X-ray flux declines as t^-1.2 over a period of ~30 days, followed by a sudden decrease to an undetectable level by EP and XMM-Newton, making it the longest afterglow emission detected among known fast X-ray transients. A bright counterpart at optical and radio wavelengths was also detected, with high peak luminosities in excess of 10^44 erg/s and 10^41 erg/s, respectively. In addition, EP241021a exhibits a non-thermal X-ray spectrum, red optical color, X-ray and optical rebrightenings in the light curves, and fast radio spectral evolution, suggesting that relativistic jets may have been launched. We discuss possible origins of EP241021a, including a choked jet with supernova shock breakout, a merger-triggered magnetar, a highly structured jet, and a repeating partial tidal disruption event involving an intermediate-mass black hole, but none can perfectly explain the multiwavelength properties. EP241021a may represent a new type of X-ray transients with months-duration evolution timescales, and future EP detections and follow-up observations of similar systems will provide statistical samples to understand the underlying mechanisms at work.

We present a detailed analysis of the long-duration GRB 241030A detected by ıt Swift. Thanks to the rapid response of XRT and UVOT, the strongest part of the prompt emission of GRB 241030A has been well measured simultaneously from optical to hard X-ray band. The time-resolved WHITE band emission shows strong variability, largely tracing the activity of the prompt gamma-ray emission, may be produced by internal shocks too. The joint analysis of the XRT and BAT data reveals the presence of a thermal component with a temperature of a few keV, which can be interpreted as the photosphere radiation, and the upper limit of the Lorentz factor of this region is found to range between approximately 20 and 80. The time-resolved analysis of the initial U-band exposure data yields a very rapid rise (\\( t^5.3\\)) with a bright peak reaching 13.6 AB magnitude around 410 seconds, which is most likely attributed to the onset of the external shock emission. The richness and fineness of early observational data have made this burst a unique sample for studying the various radiation mechanisms of gamma-ray bursts.