J/A+A/698/A98 LHAASO spectral data (Xie+, 2025)
Attempt to use traveling pulsar wind nebula modeling on the enigmatic LHAASO
dumbbell-like structure.
Xie C., Liu Y., Shao C., Cui Y., Yang L.
<Astron. Astrophys. 698, A98 (2025)>
=2025A&A...698A..98X 2025A&A...698A..98X (SIMBAD/NED BibCode)
ADC_Keywords: Gamma rays ; Energy distributions
Keywords: gamma rays: general - diffusion - neutrinos -
radiation mechanisms: non-thermal
Abstract:
The first Large High Altitude Air Shower Observatory (LHAASO) catalog
presents six enigmatic ultra-high-energy (UHE) gamma-ray sources
with lonely > 25 TeV emission being detected, which are indicated as
1LHAASO: J0007+5659u, J0206+4302u, J0212+4254u, J0216+4237u,
J1740+0948u, and J1959+1129u. No counterparts of the six sources have
been observed, except two energetic pulsars, PSR J0218+4232 and PSR
J1740+1000. Among them, 1LHAASO: J0206+4302u, J0212+4254u, and
J0216+4237u are connected on the significance map and constituted a
dumbbell-like structure. They are close in position and show a similar
spectral shape, suggesting a physical association among them. To
explain the origin of the six LHAASO sources, especially the
intriguing dumbbell-like structure, we conducted the leptonic and
hadronic modeling research according to our multiwavelength and
multimessenger study. For the dumbbell-like structure, models with
traveling-PWNe were considered. The multiwavelength and multimessenger
study was based on the Fermi-LAT, Swift-XRT, Planck, CfA 12CO survey,
and IceCube neutrino datasets. In the traveling-PWN modeling
research, we assumed an isotropic and homogeneous diffusion condition
and discussed the influence of diffusion coefficient, distance, and
proper motion velocity. No counterparts are discovered in our
multiwavelength and multimessenger study, except the two known
pulsars. The traveling-PWN modeling attempt with a single PWN appears
implausible to explain the dumbbell-like structure, as the diffusion
coefficient needs to be much lower than the Bohm limit. A double
traveling-PWNe model is also explored and can account for the results
of LHAASO-KM2A observation. However, the probability of occurrence of
this explanation is significantly lower than that of a conventional
triple PWNe explanation. Furthermore, according to our model, the only
known pulsar PSR J0218+4232 is unlikely to be associated with the
dumbbell-like structure in an isotropic and homogeneous diffusion
environment. The expected TeV emission of this pulsar is far from
explaining even the eastern part of the structure.
Description:
This is a help file for the LHAASO spectral data archived in
"wcdaul.dat" and "data.dat". These data presented in Figs. 4 and 5 of
the paper are derived from the differential fluxes and photon spectral
indexes given by Table 2 of the first LHAASO gamma-ray source catalog
(Cao, Z., Aharonian, F., An, Q., et al. 2024ApJS..271...25C 2024ApJS..271...25C,
J/ApJS/271/25).
The data file "km2adata.dat" includes the SED upper limits of WCDA at
3TeV for the six LHAASO sources studied in the article. The data is
sorted by the source names.
The data file "km2adata.dat" includes the fitting SEDs of KM2A along
with their error bars. Additionally, the data is sorted by the source
names, and eight data points are provided for each source.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
wcdaul.dat 30 6 SED upper limits of WCDA at 3TeV for the six
LHAASO sources studied in the article (fig. 4)
km2adata.dat 50 48 Fitting SEDs of KM2A along with their error bars
(fig. 5)
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See also:
J/ApJS/271/25 : The first LHAASO catalog of gamma-ray sources (Cao+, 2024)
Byte-by-byte Description of file: wcdaul.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- Source LHAASO source name, 1LHAASO JHHMM+DDMMu
21 I1 TeV Energy Gamma photon energy
23- 30 E8.3 mW/m2 upperLimit WCDA upper limit
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Byte-by-byte Description of file: km2adata.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- Source LHAASO source name, 1LHAASO JHHMM+DDMMu
21- 32 F12.8 TeV Energy Gamma photon energy
34- 41 E8.3 mW/m2 SED KM2A fitting SED
43- 50 E8.3 mW/m2 e_SED Error of KM2A fitting SED, from the error
of best-fit parameters
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Acknowledgements:
Caijin Xie, xiecj3(at)mail2.sysu.edu.cn
(End) Patricia Vannier [CDS] 14-Apr-2025