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Observation Date (UT) Observation Lat

Canonical Name:Terzan 5
TeVCat Name:TeV J1747-248
Other Names:HESS J1747-248
Source Type:Globular Cluster
R.A.:17 47 49 (hh mm ss)
Dec.:-24 48 30 (dd mm ss)
Gal Long: 3.78 (deg)
Gal Lat: 1.72 (deg)
Distance: 5.9 kpc
Flux:0.015 (Crab Units)
Energy Threshold:440 GeV
Spectral Index:2.5
Extended:Yes
Size (X):0.16 (deg)
Size (Y):0.03 (deg)
Discovery Date:2011-07
Discovered By: H.E.S.S.
TeVCat SubCat:Default Catalog

Source Notes:


H.E.S.S. Galactic Plane Survey (HGPS, 2018):
A selection of information for each of the 78 sources in the HGPS is provided in TeVCat. For full details, visit the HGPS website.

Name: HESS J1747-248
Source Class: Unid
Identified Object: None
R.A. (J2000): 266.96 deg (17 47 50)
Dec. (J2000): -24.82 deg (-24 48 56)
Positional uncertainty: 0.034 deg
Spatial Model: Gaussian
Size: 0.061 +/- 0.012 deg
Spectral Model: power law
Integral Flux > 1 TeV: 2.66e-13 +/- 4.35e-14 cm-2 s-1
Pivot Energy, E0: 1.27 TeV
Diff. Flux at E0: 2.05e-13 +/- 3.02e-14 cm-2 s-1 TeV-1
Spectral Index: 2.36 +/- 0.14
HGPS Source Notes:
Two possible associations are listed in Table A.9. "This is a list of astronomical objects, extracted from catalogs of plausible counterparts, which are are found to be spatially coincident with the HGPS source":
- 3FGL J1748.0-447 (3FGL)
- Terzan 5 (EXTRA)
"EXTRA associations: For completeness, in addition to the associations obtained through the catalog-based, automatic procedure, we add a list of 20 extra associated objects that are plausible counterparts for some HGPS sources and are not covered by the limited set of catalogs we use."


Source Association:
From Funk et al. (2012):
- "This ICRC has seen a report of a possible detection of the globular
cluster Terzan 5 with H.E.S.S. at higher energies ... The slight
offset of the gamma-ray emission from the center of globular cluster
and the rather large extension of the emission is challenging for the
Globular cluster interpretation. The chance coincidence is however
quoted at the level of 10e-4"
From Abramowski et al. (2011):
- "...it is unlikely that the association of the VHE gamma-ray source
and the GC is by chance, but due to simplifications in the probability
estimation, such a possibility cannot firmly be excluded."

Source Location
From Abramowski et al. (2011):
- R.A. (J2000): 17h 47m 49s +/- 1.8s(stat) +/- 1.3s(syst)
- Dec. (J2000): -24d 48m 30s +/- 36"(stat) +/- 20"(syst)

Source Extent:
From Abramowski et al. (2011):
- major axis: 9.6' +/- 2.4'(stat)
- minor axis: 1.8' +/- 1.2'(stat)
- orientation: 92deg +/- 6deg westwards from North

Spectral Properties:
From Abramowski et al. (2011):
- Spectral index: 2.5 +/- 0.3(stat) +/- 0.2(syst)


Seen by: H.E.S.S.
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