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Observation Date (UT) Observation Lat

Canonical Name:1ES 1959+650
TeVCat Name:TeV J1959+651
Other Names:
Source Type:HBL
R.A.:19 59 59.8 (hh mm ss)
Dec.:+65 08 55 (dd mm ss)
Gal Long: 98.00 (deg)
Gal Lat: 17.67 (deg)
Distance: z=0.048
Flux:0.64 (Crab Units)
Energy Threshold:600 GeV
Spectral Index:
Discovery Date:1999-08
Discovered By: Telescope Array
TeVCat SubCat:Default Catalog

Source Notes:

Source position and its uncertainty:
- no information available
- the source position provided by NED is used

Spectral Properties:
From Albert et al. (2006):
- Spectral index: 2.72 +/- 0.14
From Krawczynski et al. (2004):
- Spectral index (high state): 2.83 +/- 0.14(stat) +/- 0.08(syst)
- Spectral index (low state): 3.18 +/- 0.17(stat) +/- 0.08(syst)
From Tagliaferri et al. (2008):
- Spectral index (low state): 2.58 +/- 0.18

- the gamma-ray flux from 1ES 1959+650 has been found to be variable (see references)
From Benbow et al. (2011):
- an average flux of 18% that of the Crab
From Holder et al. (2003):
- during flaring, the flux reached 62% that of the Crab

Special Notes:
- Krawczynski et al. (2004) detected a so-called "orphan gamma-ray flare" from this object

Information on the jet:
From Lister et al. (2019):
- "The jet structure was too weak and compact at 15 GHz to reliably
measure any robust features. Piner et al. (2010) obtained a maximum
speed measurement of 0.0322 +/- 0.0064 mas y-1 at 43 GHz"

Seen by: Telescope Array, Whipple, MAGIC, VERITAS, FACT, LHAASO
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