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Observation Date (UT) Observation Lat

Canonical Name:KUV 00311-1938
TeVCat Name:TeV J0033-193
Other Names:
Source Type:HBL
R.A.:00 33 36 (hh mm ss)
Dec.:-19 21 00 (dd mm ss)
Gal Long: 94.24 (deg)
Gal Lat: -81.21 (deg)
Flux:0.009 (Crab Units)
Energy Threshold:147 GeV
Spectral Index:5.1
Discovery Date:2012-07
Discovered By: H.E.S.S.
TeVCat SubCat:Default Catalog

Source Notes:

This source was moved from the Newly Announced to the Default catalogue on 200409

Source Discovery:
- This detection was announced in July 2012 at the Gamma 2012 meeting in
Heidelberg by Becherini (poster) and Stegmann (presentation).
- It is the H.E.S.S. Source of the month for August 2012.

Source position and its uncertainty:
On 200612 the source position was updated from that give in NED to that given by H.E.S.S. Collaboration (2020):
From H.S.S.S. Collaboration (2020):
- R.A. (J2000): 00h33m36s +/- 06s (stat) +/- 1.3s (syst)
- Dec. (J2000): -19d21' +/- 1' (stat) +/- 1' (syst)
Position from NED:
- R.A. (J2000): 00 33 34.2
- Dec. (J2000): -19 21 33

From H.S.S.S. Collaboration (2020):
- "A power-law fitted to the Fermi/LAT data below 10 GeV and
extrapolated to the 83 GeV to 3.0 TeV energy band was used as the
intrinsic model, Fint. This was then compared to the
H.E.S.S. observations via the measured F_VHE and dF_VHE. We derive an
upper limit of z < 0.93 using Dominguez et al. (2011). In comparison,
using the Franceschini (2008) model we get a limit of z < 0.98."

From Fernandez Alonso, Pichel & Rovero (2019):
- the authors use gamma-ray observations of this object to place
constraints on its redshift. Each of the main current models for the
absorption by the extragalactic background light are utilised.
- "By comparing Fermi-LAT and HESS observations from similar time
periods and under the assumption that the TeV intrinsic spectrum is a
prolongation of the GeV spectrum, we found the measured flux to be
consistent within 1 sigma errors with the absorbed flux of a source at
z=0.5 and z=0.6 depending on the EBL model."

From Pita et al. (2013):
- from spectroscopy: 0.506 <= z <= 1.54
- from imaging: z >= 0.47
From Pita et al.(2012):
- "z ≥0.506; z =0.61 not confirmed"

Spectral Information:
From H.S.S.S. Collaboration (2020):
- The spectrum was fitted by a power-law function with:
... dN/dE = N0 (E/E0)^-A where N0= normalisation at E = E0, A = photon index. N0 and A were free in the minimisation
... A: 5.1 +/- 0.6 (stat) +/- 0.3 (syst)
... N0: 4.1 +/- 0.8 (stat) +/- 1.7 (syst) x 10e-11 TeV-1cm-2s-1
... E0: 170 GeV
... Eth: 83 GeV
... F(E>Eth): 3 +/- 1 (stat) +/- 1 (sys) x 10e-11 cm-2s-1
... F(E>147 GeV): approx. 0.9% Crab flux > 147 GeV

Seen by: H.E.S.S.
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