MAGIC detected the Geminga pulsar in VHE
Another important MAGIC paper entitled “Detection of the Geminga pulsar with MAGIC hints at a power-law tail emission beyond 15 GeV” has been published in A&A:
Abstract:
We report the detection of pulsed gamma-ray emission from the Geminga pulsar (PSR J0633+1746) between 15 GeV and 75 GeV. This is the first time a middle-aged pulsar has been detected up to these energies. Observations were carried out with the MAGIC telescopes between 2017 and 2019 using the low-energy threshold Sum-Trigger-II system. After quality selection cuts, ∼80 h of observational data were used for this analysis. To compare with the emission at lower energies below the sensitivity range of MAGIC, 11 years of Fermi-LAT data above 100 MeV were also analysed. From the two pulses per rotation seen by Fermi-LAT, only the second one, P2, is detected in the MAGIC energy range, with a significance of 6.3σ. The spectrum measured by MAGIC is well-represented by a simple power-law of spectral index Γ = 5.62 ± 0.54, which smoothly extends the Fermi-LAT spectrum. A joint fit to MAGIC and Fermi-LAT data rules out the existence of a sub-exponential cut-off in the combined energy range at the 3.6σ significance level. The power-law tail emission detected by MAGIC is interpreted as the transition from curvature radiation to Inverse Compton Scattering of particles accelerated in the northern outer gap.
And it is a HIGHLIGHT of the journal!
As a reminder, 4 years ago MAGIC has published another paper on Geminga. At that time, we did not find any significant detection, but we could do it now!
Also, 22 years ago I had a paper on the analysis of this pulsar, but in the optical wavelengths:
Shearer A., …, Neustroev V., et al.: “Possible pulsed optical emission from Geminga”, 1998, A&A., V.335, L21-L24
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