Observational and theoretical results indicate that low-redshift BL Lacertae objects are the most likely extragalactic sources to be detectable at TeV energies. In this paper we present the results of observations of 4 BL Lacertae objects (PKS0521-365, EXO 0423.4-0840, PKS2005-489 and PKS2316-423) made between 1993 and 1996 with the CANGAROO 3.8 m imaging Čerenkov telescope. During the period of these observations the gamma-ray energy threshold of the 3.8m telescope was ∼2 TeV. Searches for steady long-term emission have been made, and, inspired by the TeV flares detected from Mkn 421 and Mkn 501, a search on a night-by-night timescale has also been performed for each source. Comprehensive Monte Carlo simulations are used to estimate upper limits for both steady and short timescale emission.
|Number of pages||6|
|Journal||Astronomy and Astrophysics|
|Publication status||Published - Sept 1 1998|
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science