| Canonical Name: | HESS J1745-303 |
| TeVCat Name: | TeV J1745-303 |
| Other Names: | G359.1-0.5, 3EG J1744−3011,
2FHL J1745.1-3035
3FGL J1745.1-3011 |
| Source Type: | SNR/Molec. Cloud |
| R.A.: | 17 45 02.10 (hh mm ss) |
| Dec.: | -30 22 14.00 (dd mm ss) |
| Gal Long: | 358.71 (deg) |
| Gal Lat: | -0.64 (deg) |
| Distance: | |
| Flux: | 0.05 (Crab Units) |
| Energy Threshold: | 200 GeV |
| Spectral Index: | 1.82 |
| Extended: | Yes |
| Size (X): | 0.21 (deg) |
| Size (Y): | 0.09 (deg) |
| Discovery Date: | 2006-01 |
| 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 J1745-303 |
| Source Class: | Unid |
| Identified Object: | None |
| R.A. (J2000): | 266.14 deg (17 44 34) |
| Dec. (J2000): | -30.39 deg (-30 23 11) |
| Positional uncertainty: | 0.065 deg |
| Spatial Model: | Gaussian |
| Size: | 0.179 +/- 0.020 deg |
| Spectral Model: | power law |
| Integral Flux > 1 TeV: | 1.09e-12 +/- 7.83e-14 cm-2 s-1 |
| Pivot Energy, E0: | 0.87 TeV |
| Diff. Flux at E0: | 2.47e-12 +/- 1.35e-13 cm-2 s-1 TeV-1 |
| Spectral Index: | 2.57 +/- 0.06 |
| HGPS Source Notes: | |
| | |
This is one of eleven HGPS sources that "do not have any associations with known physical objects, although some are associated
with HE gamma-ray sources."
- "HESS J1745−303 is close to, but offset from, SNR G359.1−0.5. Suzaku observations have revealed neutral iron line emission in the region, suggesting the presence of
molecular matter and making this object another possible case of a CR-illuminated cloud (Bamba et al. 2009).
We find this object also to be associated with the HE
gamma-ray sources 2FHL J1745.1−3035 and 3FGL J1745.1−3011."
This source is one of the twelve source whose HGPS results differed from those published in previous publications.
- "HESS J1745−303 was studied in Aharonian et al. (2008) with 80 h of data. Its morphology is complex and three subregions,
called A, B, and C, were discussed. In the
HGPS analysis, with more than 160 h on the region, two distinct sources are detected: HESS J1745−303 and HESS J1746−308. The former encloses the hotspots A and C
and a fraction of region B. A second source is now detected at b = −1.11 deg latitude. This source contains part of hotspot B and emission at large latitudes that was
not significant before, likely due to the additional livetime obtained since 2008. It is fainter and its spectrum is very steep but poorly constrained. There is also
a third extended (radius ∼ 0.5 deg) Gaussian component in the region. It is currently considered to be a diffuse component. The association of the two sources and the
extended component is unclear and the exact morphology of the VHE emission in the region will require dedicated studies."
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 J1745.1−3011 (3FGL)
- 2FHL J1745.1−3035 (2FHL)
Source position and its uncertainty:
Position updated to this one on 160204:
From
Aharonian et al. (2008):
- R.A. (J2000): 17 45 02.10
- Dec. (J2000): -30 22 14.00
- No statistical or systematic uncertainty is provided
From
Aharonian et al. (2006):
- l: 358.71 +/- 0.04 (deg)
- b: -0.64 +/- 0.05 (deg)
- R.A. (deg): 266.26 (Convert to HMS: 17 45 02.4)
- Dec. (deg): -30.37 (Convert to HMS: -30 22 12
Source Extent:
From
Aharonian et al. (2008):
- the entire source comprises a region with a radius of 0.4deg
From
Aharonian et al. (2006):
- semi-major axis: 0.21 +/- 0.06 deg
- semi-minor axis: 0.09 +/- 0.04 deg
- angle: 54 +/- 7 deg
...measured counter-clk wrt the positive Gal. Lat. axis
Spectral Properties:
From
Aharonian et al. (2008):
- Spectral index: 2.71 +/- 0.11(stat) +/- 0.2(syst)
From
Aharonian et al. (2008):
- Spectral index: 1.82 +/- 0.29(stat) +/- 0.2(syst)
Source Classification:
From
H.E.S.S. Collaboration (2018):
- "HESS J1745-303 was studied in
Aharonian et al. (2008b) with 80 h of
data. Its morphology is complex and three subregions, called A, B, and
C, were discussed. In the HGPS analysis, with more than 160 h on the
region, two distinct sources are detected: HESS J1745-303 and
HESS J1746−308. The former encloses the hotspots A and C and a
fraction of region B. A second source is now detected at b = -1.11 deg
latitude. This source contains part of hotspot B and emission at large
latitudes that was not significant before, likely due to the
additional livetime obtained since 2008."
- "There is also a third extended (sigma approx. 0.5 deg ) Gaussian
component in the region. It is currently considered to be a diffuse
component. The association of the two sources and the extended
component is unclear and the exact morphology of the VHE emission in
the region will require dedicated studies."
- Associations for this source listed in this paper:
- "HESS J1745-303 is close to, but offset from, SNR G359.1-0.5.
Suzaku observations have revealed neutral iron line emission in the
region, suggesting the presence of molecular matter and making this
object another possible case of a CR-illuminated cloud (
Bamba et al. 2009).
We find this object also to be associated with the HE gamma-ray
sources 2FHL J1745.1-3035 and 3FGL J1745.1-3011.
From
Hui et al. (2016)
- "For HESS J1745-303, we found that its MeV-GeV emission is mainly
originated from the "Region A" of the TeV feature. Its gamma-ray
spectrum can be modelled with a single power-law with a photon index
of approx 2.5 from few hundreds MeV to TeV. Moreover, an elongated
feature, which extends from "Region A" towards north-west for approx
1.3deg, is discovered for the first time. The orientation of this
feature is similar to that of a large scale atomic/molecular gas
distribution."
From
Aharonian et al. (2008):
- "Though no single counterpart is found to fully explain the VHE
emission, we postulate that at least a fraction of the VHE source may
be explained by a supernova-remnant/molecular-cloud association and/or
a high-spin-down-flux pulsar."
- The SNR associated would be G359.1-0.5. Candidate pulsars are PSR
B1742-30 and PSR J1747-2958.
- "Since the emission appears to have a complicated morphology with
more than one peak in the excess image, the possibility that HESS
J1745-303 is more than one source was explored. First, three emission
peaks were determined, located at the positions A, B, and C shown in
Fig. 1."
From
de Naurois (2011)
- an old mixed-morphology SNR
From
Tibolla et al. (2011)
- suggests that hot spot B in this source is an ancient PWN
Seen by: H.E.S.S., VERITAS
-
2FHL J1745.1\textendash3035: A Newly Discovered, Powerful Pulsar Wind Nebula Candidate
Marchesi, S. et al., ApJ 964 p132 (2024) [LINK]
-
VERITAS Observations of the Galactic Center Region at Multi-TeV Gamma-Ray Energies
Adams, C.B. et al., arXiv e-prints parXiv:2104.12735 (2021) [LINK]
-
Molecular environments of the supernova remnant G359.1-0.5
Eppens, L.K. et al., arXiv e-prints parXiv:2002.08921 (2020) [LINK]
-
Uniform distribution of the extremely overionized plasma associated with the supernova remnant G359.1-0.5
Suzuki, Hiromasa et al., arXiv e-prints parXiv:2003.07576 (2020) [LINK]
-
Dense molecular gas at 12 mm towards Galactic TeV gamma-ray sources
de Wilt, P. et al., MNRAS 468 p2093-2113 (2017) [LINK]
-
Observing two dark accelerators around the Galactic Centre with Fermi Large Area Telescope
Hui, C.Y. et al., MNRAS p (2016) [LINK]
-
A statistical study of Galactic SNR source spectra detected at >GeV energies
Mandelartz, M. and Becker Tjus, J., ArXiv e-prints p (2013) [LINK]
-
Unified model for the gamma-ray emission of supernova remnants
Yuan, Q. et al., ArXiv e-prints p (2012) [LINK]
-
GeV analysis of mixed morphology supernova remnants interacting with molecular clouds
Ergin, T. and Ercan, E.N., 1505 p265-268 (2012) [LINK]
-
A study of dense molecular gas towards galactic TeV gamma-ray sources
de Wilt, P. et al., American Institute of Physics Conference Series, Vol. 1505, p277-280 (2012) [LINK]
-
Exploring the dark accelerator HESS J1745-303 with Fermi Large Area Telescope
Hui, C.Y. et al., ArXiv e-prints p (2011) [LINK]
-
New developments in the ancient PulsarWind Nebulae scenario
Tibolla, O. et al., ArXiv e-prints p (2011) [LINK]
-
Ancient Pulsar Wind Nebulae in light of recent GeV and TeV observations
Tibolla, O. et al., ArXiv e-prints p (2011) [LINK]
-
Exploring a SNR/molecular cloud association within HESS J1745-303
Aharonian, F. et al., A&A 483 p509-517 (2008) [LINK]
-
X-Ray Observation of Very High Energy Gamma-Ray Source, HESS J1745-303, with Suzaku
Bamba, A. et al., ArXiv e-prints p (2008) [LINK]
-
The H.E.S.S. Survey of the Inner Galaxy in Very High Energy Gamma Rays
Aharonian, F. et al., ApJ 636 p777-797 (2006) [LINK]
Want a reference added? Send a bibtex entry to
the TeVCat Team
