This study considers how governments use state-sponsored propaganda and state violence in tandem to repress social movements and, in so doing, exacerbate polarization. We specifically focus on cases ...in young and non-democracies in East and Southeast Asia: China and Hong Kong, the Free Papua Movement in Indonesia, and Myanmar’s more recent coup. Using a time series analysis, our analysis reveals a temporal relationship between state propaganda and violence; however, we do not find much evidence that these state actions Granger-cause social movement activities. The exception to this is in Myanmar, where we find that repressive state actions decrease activity in Facebook groups criticizing the Tatmadaw, which in turn increases offline protest activities.
In this study, we developed a new proton detector system called CATCH, which was designed for a scattering experiment involving a Σ hyperon and a proton (J-PARC E40). CATCH is a cylindrical detector ...system covering an inner target that can be used to measure the trajectory and energy of a proton emitted from the target for the kinematic identification of a Σp scattering event. It comprises a cylindrical fiber tracker (CFT), a bismuth germanate (BGO) calorimeter, and a plastic scintillator hodoscope (PiID), which are coaxially arranged from the inner to the outer sides. The CFT is a tracking detector consisting of 5,000 scintillation fibers, and it has two types of cylindrical layers in which the fibers are arranged in straight and spiral configurations. 24 BGO crystals are placed around the CFT to measure the kinetic energy of the recoil proton. The PiID is used to determine whether the recoil proton is stopped in the BGO calorimeter . We performed proton–proton (pp) and proton–carbon (pC) scattering experiments using an 80 MeV proton beam to evaluate the performance of CATCH. The total energy resolution for the recoil proton was 2.8 MeV in σ for the entire angular region after the energy calibrations of the BGO calorimeter and the CFT. The angular resolution of the CFT was 1.27 degrees in σ for the proton, and the time resolution was more than 1.8 ns in σ. We also developed an analysis method for deriving the cross section of the pp scattering using CATCH. The obtained relative differential cross section for the pp elastic scattering was consistent with that obtained by reliable partial wave analysis, and the systematic error was maintained at below 10%. These performance results satisfy our requirements for a reliable detection system for the Σp scattering experiment conducted at J-PARC.
The Pierre Auger Collaboration (Auger) recently reported a correlation between the arrival directions of cosmic rays with energies above 39 EeV and the flux pattern of 23 nearby starburst galaxies ...(SBGs). In this Letter, we tested the same hypothesis using cosmic rays detected by the Telescope Array experiment (TA) in the 9 yr period from 2008 May to 2017 May. Unlike the Auger analysis, we did not optimize the parameter values but kept them fixed to the best-fit values found by Auger, namely 9.7% for the anisotropic fraction of cosmic rays assumed to originate from the SBGs in the list and 12 9 for the angular scale of the correlations. The energy threshold that we adopted is 43 EeV, corresponding to 39 EeV in Auger when taking into account the energy-scale difference between two experiments. We find that the TA data is compatible with isotropy to within 1.1 and with the Auger result to within 1.4 , meaning that it is not capable to discriminate between these two hypotheses.
The Fukushima Daiichi Nuclear Power Station (FDNPS), operated by Tokyo Electric Power Company Holdings, Inc., went into meltdown after the occurrence of a large tsunami caused by the Great East Japan ...Earthquake of March 11, 2011. The radiation distribution measurements inside the FDNPS buildings are indispensable to execute decommissioning tasks in the reactor buildings. We have developed a three-dimensional (3D) image reconstruction method for radioactive substances using a compact Compton camera. Moreover, we succeeded in visually recognizing the position of radioactive substances in real space by the integration of 3D radiation images and the 3D photo-model created using photogrammetry.
The relative abundance of cosmic ray nickel nuclei with respect to iron is by far larger than for all other transiron elements; therefore it provides a favorable opportunity for a low background ...measurement of its spectrum. Since nickel, as well as iron, is one of the most stable nuclei, the nickel energy spectrum and its relative abundance with respect to iron provide important information to estimate the abundances at the cosmic ray source and to model the Galactic propagation of heavy nuclei. However, only a few direct measurements of cosmic-ray nickel at energy larger than ∼3 GeV/n are available at present in the literature, and they are affected by strong limitations in both energy reach and statistics. In this Letter, we present a measurement of the differential energy spectrum of nickel in the energy range from 8.8 to 240 GeV/n, carried out with unprecedented precision by the Calorimetric Electron Telescope (CALET) in operation on the International Space Station since 2015. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The particle's energy is measured by a homogeneous calorimeter (1.2 proton interaction lengths, 27 radiation lengths) preceded by a thin imaging section (3 radiation lengths) providing tracking and energy sampling. This Letter follows our previous measurement of the iron spectrum 1O. Adriani et al. (CALET Collaboration), Phys. Rev. Lett. 126, 241101 (2021).PRLTAO0031-900710.1103/PhysRevLett.126.241101, and it extends our investigation on the energy dependence of the spectral index of heavy elements. It reports the analysis of nickel data collected from November 2015 to May 2021 and a detailed assessment of the systematic uncertainties. In the region from 20 to 240 GeV/n our present data are compatible within the errors with a single power law with spectral index -2.51±0.07.
Microcrystals of coesite and stishovite were discovered as inclusions in amorphous silica grains in shocked melt pockets of a lunar meteorite Asuka-881757 by micro-Raman spectrometry, scanning ...electron microscopy, electron back-scatter diffraction, and transmission electron microscopy. These high-pressure polymorphs of SiO₂ in amorphous silica indicate that the meteorite experienced an equilibrium shock-pressure of at least 8–30 GPa. Secondary quartz grains are also observed in separate amorphous silica grains in the meteorite. The estimated age reported by the ³⁹Ar/⁴⁰Ar chronology indicates that the source basalt of this meteorite was impacted at 3,800 Ma ago, time of lunar cataclysm; i.e., the heavy bombardment in the lunar surface. Observation of coesite and stishovite formed in the lunar breccias suggests that high-pressure impact metamorphism and formation of high-pressure minerals are common phenomena in brecciated lunar surface altered by the heavy meteoritic bombardment.
To document the clinicopathologic characteristics and survival of patients undergoing esophagectomy for squamous carcinoma of the thoracic esophagus, and to examine the factors contributing to ...improvements in outcome noted in patients with advanced carcinoma.
Japanese and some Western surgeons recently have reported that radical esophagectomy with extensive lymphadenectomy conferred a survival advantage to patients with esophageal carcinoma. The factors contributing to this improvement in results have not been well defined.
From 1981 to 1995, 419 patients with carcinoma of the thoracic esophagus underwent esophagectomy at the Keio University Hospital. The clinicopathologic characteristics and survival of patients treated between 1981 and 1987 were compared with those of patients treated between 1988 and 1995. Multivariate analysis using the Cox regression model was carried out to evaluate the impact of 15 variables on survival of patients with p stage IIa to IV disease. Several variables related to prognosis were examined to identify differences between the two time periods.
The 5-year survival rate for all patients was 40.0%. The 5-year survival rate was 17.7% for p stage IIa to IV patients treated during the earlier period and 37.6% for those treated during the latter period. The Cox regression model revealed seven variables to be important prognostic factors. Of these seven, three (severity of postoperative complications, degree of residual tumor, and number of dissected mediastinal nodes) were found to be significantly different between the earlier and latter periods.
The survival of patients undergoing surgery for advanced carcinoma (p stage IIa to IV) of the thoracic esophagus has improved during the past 15 years. The authors' data suggest that this improvement is due mainly to advances in surgical technique and perioperative management.
Abstract
Gamma rays from HESS J1849−000, a middle-aged TeV pulsar wind nebula (PWN), are observed by the Tibet air shower array and the muon detector array. The detection significance of gamma rays ...reaches 4.0
σ
and 4.4
σ
levels above 25 TeV and 100 TeV, respectively, in units of the Gaussian standard deviation
σ
. The energy spectrum measured between 40 TeV <
E
< 320 TeV for the first time is described with a simple power-law function of
dN
/
dE
=
(
2.86
±
1.44
)
×
10
−
16
(
E
/
40
TeV
)
−
2.24
±
0.41
TeV
−
1
cm
−
2
s
−
1
. The gamma-ray energy spectrum from the sub-TeV (
E
< 1 TeV) to sub-PeV (100 TeV <
E
< 1 PeV) ranges, including the results of previous studies, can be modeled with the leptonic scenario, i.e., inverse Compton scattering by high-energy electrons accelerated by the PWN of PSR J1849−0001. On the other hand, the gamma-ray energy spectrum can also be modeled with the hadronic scenario in which gamma rays are generated from the decay of neutral pions produced by collisions between accelerated cosmic-ray protons and the ambient molecular cloud found in the gamma-ray-emitting region. The cutoff energy of cosmic-ray protons
E
p,cut
is estimated as
log
10
(
E
p
,
cut
/
TeV
)
=
3.73
−
0.66
+
2.98
, suggesting that protons are accelerated up to the PeV energy range. Our study thus proposes that HESS J1849−000 should be further investigated as a new candidate as a Galactic PeV cosmic-ray accelerator, or “PeVatron.”
Abstract
HESS J1843–033 is a very high energy gamma-ray source whose origin remains unidentified. This work presents, for the first time, the energy spectrum of gamma rays beyond 100 TeV from the ...HESS J1843–033 region using the data recorded by the Tibet air shower array and its underground muon detector array. A gamma-ray source with an extension of 0.°34 ± 0.°12 is successfully detected above 25 TeV at (
α
,
δ
) = (281.°09 ± 0.°10, −3.°76 ± 0.°09) near HESS J1843–033 with a statistical significance of 6.2
σ
, and the source is named TASG J1844–038. The position of TASG J1844–038 is consistent with those of HESS J1843–033, eHWC J1842–035, and LHAASO J1843–0338. The measured gamma-ray energy spectrum in 25 TeV <
E
< 130 TeV is described with
dN
/
dE
=
(
9.70
±
1.89
)
×
10
−
16
(
E
/40 TeV)
−3.26±0.30
TeV
−1
cm
−2
s
−1
, and the spectral fit to the combined spectra of HESS J1843–033, LHAASO J1843–0338, and TASG J1844–038 implies the existence of a cutoff at 49.5 ± 9.0 TeV. Associations of TASG J1844–038 with SNR G28.6–0.1 and PSR J1844–0346 are also discussed in detail for the first time.
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