Multi-wavelength observation of MAXI J1820+070 with MAGIC, VERITAS and H.E.S.S

J. Hoang; E. Molina; M. López; M. Ribó; O. Blanch; J. Cortina; G. Maier; N. Park; M. de Naurois; E. de Ona Wilhelmi; J. P. Ernenwein; D. Malyshev; A. Mitchell; S. Ohm; R. Zanin

arXiv · 1908.06958

Multi-wavelength observation of MAXI J1820+070 with MAGIC, VERITAS and H.E.S.S

J. Hoang·E. Molina·M. López·M. Ribó·O. Blanch·J. Cortina·G. Maier·N. Park·M. de Naurois·E. de Ona Wilhelmi·J. P. Ernenwein·D. Malyshev·A. Mitchell·S. Ohm·R. Zanin

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Abstract

MAXI J1820+070 is a new low-mass microquasar hosting a black hole recently discovered in X-rays by the MAXI instrument. It is the counterpart of ASASSN-18ey, discovered in optical a few days before by ASAS-SN. This source underwent a major outburst in 2018, during which it completed the typical "q-shaped" path in the hardness-intensity diagram. MAGIC, VERITAS and H.E.S.S. gamma-ray telescopes observed the sky position of MAXI J1820+070 for a total of more than 90 hours in 2018. In addition, some observations were carried out using MAGIC Central Pixel - a dedicated central pixel capable of detecting fast optical signals (10 kHz sampling rate, peak sensitivity in the U-band). This contribution presents the methods used to search for transient optical and very high energy gamma-ray emission from MAXI J1820+070, as well as the latest results in these energy ranges.

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J. Hoang, E. Molina, M. López, M. Ribó, O. Blanch, J. Cortina, G. Maier, N. Park, M. de Naurois, E. de Ona Wilhelmi, J. P. Ernenwein, D. Malyshev, A. Mitchell, S. Ohm, R. Zanin. 2019-08-19. Multi-wavelength observation of MAXI J1820+070 with MAGIC, VERITAS and H.E.S.S. https://arxiv.org/abs/1908.06958

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