Cutoff in the TeV energy spectrum of Markarian 421 during strong flares in2001

Citation
F. Krennrich et al., Cutoff in the TeV energy spectrum of Markarian 421 during strong flares in2001, ASTROPHYS J, 560(1), 2001, pp. L45-L48
Citations number
37
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTROPHYSICAL JOURNAL
ISSN journal
0004-637X → ACNP
Volume
560
Issue
1
Year of publication
2001
Part
2
Pages
L45 - L48
Database
ISI
SICI code
0004-637X(20011010)560:1<L45:CITTES>2.0.ZU;2-V
Abstract
Exceptionally strong and long- lasting flaring activity of the blazar Mrk 4 21 occurred between 2001 January and March. Based on the excellent signal- to- noise ratio of the data, we derive the energy spectrum between 260 GeV and 17 TeV with unprecedented statistical precision. The spectrum is not we ll described by a simple power law even with a curvature term. Instead, the data can be described by a power law with exponential cutoff: dN/dE propor tional to E(-2.14 +/-0.03 stat)e(-E/E0) m(-2) s(-1) TeV-1 with E0=4.3 +/-0. 3(stat) TeV. Mrk 421 is the second gamma -ray blazar that unambiguously exh ibits an absorption- like feature in its spectral energy distribution at 3- 6 TeV.