| Canonical Name: | LHAASO J2226+6057 |
| TeVCat Name: | TeV J2227+609 |
| Other Names: | VER J2227+608
Boomerang Nebula
SNR G106.3+2.7
PSR J2229+6114 |
| Source Type: | UNID |
| R.A.: | 22 27 00 (hh mm ss) |
| Dec.: | +60 57 00 (dd mm ss) |
| Gal Long: | 106.28 (deg) |
| Gal Lat: | 2.84 (deg) |
| Distance: | |
| Flux: | 1.05 (Crab Units) |
| Energy Threshold: | 100000 GeV |
| Spectral Index: | 3.01 |
| Extended: | Yes |
| Size (X): | 0.00 (deg) |
| Size (Y): | 0.00 (deg) |
| Discovery Date: | 2021-05 |
| Discovered By: | LHAASO |
| TeVCat SubCat: | Default Catalog |
Source Notes:
Details of the source detection:
From
Cao et al. (2021):
- "At 100 TeV, the angular and energy resolutions are about 15–20 arcmin
and better than 20%, respectively, allowing adequate spectroscopic and
morphological studies."
- "The statistical significance of the detection above 100 TeV is calculated
using a 0.3deg extension template"
- "Crab Units (CU), flux of the Crab Nebula at 100 TeV; 1 CU = 6.1 x 10-17 photons TeV-1 cm-2 s-1)"
- Significance above 100 TeV: 13.6 sigma
- E_max (PeV): 0.57 +/- 0.19
- Differential photon flux at 100 TeV (CU): 1.05 +/- 0.16
- On-source events/Off-source events: 60/6.2
- Exposure (hr): 2401.3
Source Position:
From
Cao et al. (2021):
- R.A. (J2000): 336.75 = 22h 27m 00s
- Dec. (J2000): +60.95 = +60d 57m
Spectral Properties:
From
Cao et al. (2021):
- "For the three most significantly detected sources, LHAASO J1825-1326,
LHAASO J1908+0621 and LHAASO J2226+6057, we determine their SEDs."
- The authors show "the spectral energy distributions of three
luminous sources with fluxes exceeding 1 CU (at 100 TeV): LHAASO
J1825-1326, LHAASO J1908+0621 and LHAASO J2226+6057. Above 100 TeV,
the spectra of these sources are steep, characterized by a power-law
photon index of approx. 3. However, a closer look reveals that
between 10 TeV and 500 TeV, the spectra experience gradual
steepening with energy. To explore this tendency, the spectra were
fitted by the so-called log-parabola function dN/dE ∝ E-A(E), where
the local photon index A(E) = a + blogE (a and b are free
parameters) characterizes the slope of the tangent. For all three
spectra, the log-parabola fits are preferred over simple power-law
fits. The gradual steepening of multi-hundred-teraelectronvolt gamma
rays is partly due to the photon-photon absorption that occurs
during their interactions with the diffuse far-infrared and
microwave radiation fields."
- For LHAASO J2226+6057 the parameters of the fit are:
... a: 1.56
... b: 0.88
... A: 3.01
Possible Origin:
From
Cao et al. (2021):
- This list contains sources potentially at the origin of the LHAASO source, together with their class, their distance, age and luminosity
- SNR G106.3+2.7, Supernova Renmant, Distance: 0.8 kpc, Age: approx. 10 kyr
- PSR J2229+6614, Pulsar, Distance: 0.8 kpc, Age: approx. 10 kyr, L_s: 2.2 x10e37
Potential TeV Counterparts:
From
Cao et al. (2021):
- This list contains "Nearby teraelectronvolt sources within 1deg of the centre of the LHAASO source"
-
VER J2227+608
-
Boomerang Nebula
Details of the source detection:
From
Cao et al. (2021):
- "At 100 TeV, the angular and energy resolutions are about 15–20 arcmin
and better than 20%, respectively, allowing adequate spectroscopic and
morphological studies."
- "The statistical significance of the detection above 100 TeV is calculated
using a 0.3deg extension template"
- "Crab Units (CU), flux of the Crab Nebula at 100 TeV; 1 CU = 6.1 x 10-17 photons TeV-1 cm-2 s-1)"
- Significance above 100 TeV: 8.3 sigma
- E_max (PeV): 0.43 +/- 0.05
- Differential photon flux at 100 TeV (CU): 0.38 +/-0.09
- On-source events/Off-source events: 30/6.4
- Exposure (hr): 2525.8
Source Position:
From
Cao et al. (2021):
- R.A. (J2000): 317.15 = 21h 08m 36s
- Dec. (J2000): +51.95 = +51d 57m 00s
Possible Origin:
From
Cao et al. (2021):
- No source is identified as a possible origin.
Potential TeV Counterparts:
From
Cao et al. (2021):
- There are no nearby TeV sources (i.e. within 1 deg of the centre of the LHAASO source).
Pevatron:
From
Mitchell (2021):
- this source is included in a list of Galactic sources currently known
to produce gamma-ray emission above 100 TeV.
Seen by: LHAASO
-
Study of maximum electron energy of sub-PeV pulsar wind nebulae by multiwavelength modelling
Joshi, Jagdish C. et al., arXiv e-prints parXiv:2205.00521 (2022) [LINK]
-
Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 gamma-ray Galactic sources
Cao, Z., Aharonian, F.A., An, Q., et al., Nature 594 p33-36 (2021) [LINK]
-
Strong constraints on Lorentz violation using new gamma-ray observations around PeV
Chen, Liang et al., arXiv e-prints parXiv:2105.07927 (2021) [LINK]
-
Constraints on Hadronic Contribution to LHAASO Sources with Neutrino Observations
Huang, Tian-Qi and Li, Zhuo, arXiv e-prints parXiv:2105.09851 (2021) [LINK]
-
Ultrahigh-energy photons from LHAASO as probes of Lorentz symmetry violations
Li, Chengyi and Ma, Bo-Qiang, arXiv e-prints parXiv:2105.07967 (2021) [LINK]
-
A Possible Hadronic Origin of TeV Photon Emission from SNR G106.3+2.7
Yang, Chuyuan et al., arXiv e-prints parXiv:2106.02629 (2021) [LINK]
-
Status of Ground-based and Galactic Gamma-ray Astronomy
Mitchell, A.M.W., arXiv e-prints parXiv:2109.13753 (2021) [LINK]
-
The Hunt for Pevatrons: The Case of Supernova Remnants
Cristofari, P., arXiv e-prints parXiv:2110.07956 (2021) [LINK]
-
HAWC J2227+610: a potential PeVatron candidate for the CTA in the northern hemisphere
Verna, G. et al., arXiv e-prints parXiv:2110.07939 (2021) [LINK]
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