The supermassive black hole (SMBH) in the center of our Milky Way galaxy, Sagittarius A *, is by far the closest object to us, about 25,000 light-years away. Although it is not as active or luminous as other SMBHs, its relative proximity offers astronomers a unique opportunity to probe what is happening near the "edge" of a black hole. Monitored on the radio since its discovery and, more recently, in the infrared and X-rays, Sgr A * appears to accumulate very little material, representing only a few hundredths of the Earth's mass per year. Its X-ray emission is persistent, probably because of the fast movements of electrons in the warm accretion flow associated with the black hole. Once a day, there are also very variable emission torches; they appear more often in the infrared than in the X-rays. Some submillimeter wave length surges have also been tentatively linked to infrared pulses, although their synchronization seems delayed with respect to infrared events. Despite these intensive observational efforts, the physical mechanisms that produce flaring around this SMBH are still unknown and are the subject of intense theoretical modeling.
CfA astronomers Steve Willner, Joe Hora, CfA astronomers Giovanni Fazio and Howard Smith joined their colleagues to undertake a systematic campaign of simultaneous observations on several flaring lengths in SagA * with the help of observatories. Spitzer and Chandra (the submillimeter matrix was also used.) In over a hundred hours of data collected over four years (the longest dataset ever obtained), the team observed four stray light events in X-rays. and in the infrared in which the X-ray event appears to result in the infrared of ten to twenty minutes .The correlation between the peaks observed implies that there is some physical connection between them, and the slight difference in timing is in agreement with models describing eruptions as coming from accelerations and shocks of magnetically driven particles. The exact and simultaneous results can not be totally excluded, but the results are nonetheless incompatible with some of the more exotic models that involve the relativistic electron movement. If the future simultaneous observations planned for the summer of 2019 are also flamed, they may create new constraints on the time shift and associated physical models.
Remarkable eruptions of the galactic center
H. Boyce et al. Simultaneous X-ray and infrared observations of the variability of Sagittarius A *, The astrophysical journal (2019). DOI: 10.3847 / 1538-4357 / aaf71f