Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-13T08:51:26.850Z Has data issue: false hasContentIssue false
  • English
  • Français

A Possible Discovery of a Flaring 1012 eV Gamma-Ray Source near the Red Dwarf EV Lac

Published online by Cambridge University Press:  12 April 2016

I.Yu. Alekseev ,
N.N. Chalenko ,
V.P. Fomin ,
R.E. Gershberg ,
O.R. Kalekin ,
Yu.I. Neshpor  and
A.A. Stepanian
I.Yu. Alekseev
Affiliation:
Crimean Astrophysical Observatory, Nauchny, Crimea 334413, Ukraine
N.N. Chalenko
Affiliation:
Crimean Astrophysical Observatory, Nauchny, Crimea 334413, Ukraine
V.P. Fomin
Affiliation:
Crimean Astrophysical Observatory, Nauchny, Crimea 334413, Ukraine
R.E. Gershberg
Affiliation:
Crimean Astrophysical Observatory, Nauchny, Crimea 334413, Ukraine
O.R. Kalekin
Affiliation:
Crimean Astrophysical Observatory, Nauchny, Crimea 334413, Ukraine
Yu.I. Neshpor
Affiliation:
Crimean Astrophysical Observatory, Nauchny, Crimea 334413, Ukraine
A.A. Stepanian
Affiliation:
Crimean Astrophysical Observatory, Nauchny, Crimea 334413, Ukraine

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

During the 1994 coordinated observations of the red dwarf flare star EV Lac, the star was monitored in the very high energy (VHE) γ-ray range around 1012 eV with the Crimean ground-based γ-ray telescope GT-48. This telescope consists of two identical optical systems (Vladimirsky et al. 1994) which were directed in parallel on EV Lac.

The detection principle of the VHE γ-rays is based on the Čerenkov radiation emitted by relativistic electrons and positrons. The latter are generated in the interaction of the γ-rays with nuclei in the Earth’s atmosphere that leads to an appearance of a shower of charged particles and γ-quanta. The duration of the Cherenkov radiation flash is very short, just about a few nanoseconds. The angular size of the shower is ∼ 1°. To detect such flashes we use an optical system with large area mirrors and a set of 37 photomultipliers (PMs) in the focal plane. Using the information from these PMs which are spaced hexagonally and correspond to a field of view of 2°.6 on the sky, we can obtain the image of an optical flash. The electronic device permits us to detect nanosecond flashes (40 ns exposure time and 12 μs readout dead-time).

Type
Flares in Late-type Stars: Radio and Optical
Information
International Astronomical Union Colloquium , Volume 151: Flares and Flashes , 1995 , pp. 78 - 79
Copyright
Copyright © Springer-Verlag 1995

References

Hillas, A.M., 1985, in Proc. 19th Internat. Cosmic Ray Conf. 3, Jones, F.C., Adams, J., Mason, G.M. (eds.), p. 445 Google Scholar
Seiradakis, J.H., Avgoloupis, S., Mavridis, L.N., Vaivoglis, P., Fürst, E., 1993, Proc. 1st Panhellenic Astron. Meeting, Athens, Sept. 21-23, 1992, p. 261 Google Scholar
Stepanian, A.A., 1994, Izv. Krymsk. Astrofiz. Obs. 91, 56 Google Scholar
Vladimirsky, B.M., Zyskin, Yu.L., Kornienko, A.P., Neshpor, Yu.I., Stepanian, A.A., Fomin, V.P., Shitov, V.G., 1994, Izv. Krymsk. Astrofiz. Obs. 91, 74 Google Scholar