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In this work, we reanalyzed 11 years of spectral data from the Fermi Large Area Telescope (Fermi-LAT) of currently observed starburst galaxies (SBGs) and star-forming galaxies (SFGs). We used a one-zone model provided by NAIMA and the hadronic origin to explain the GeV observation data of the SBGs and SFGs. We found that a protonic distribution of a power-law form with an exponential cutoff can explain the spectra of most SBGs and SFGs. However, it cannot explain the spectral hardening components of NGC 1068 and NGC 4945 in the GeV energy band. Therefore, we considered the two-zone model to well explain these phenomena. We summarized the features of two model parameters, including the spectral index, cutoff energy, and proton energy budget. Similar to the evolution of supernova remnants (SNRs) in the Milky Way, we estimated the protonic acceleration limitation inside the SBGs to be the order of 102 TeV using the one-zone model; this is close to those of SNRs in the Milky Way.

Supernova remnant RX J1713.7-3946 (also named as G347.3-0.5) has exhibited largest surface brightness, detailed spectral and shell-type morphology, it is one of the brightest TeV sources. The recent H.E.S.S. observation of RX J1713.7-3946 revealed \textbf{a} broken power-law spectrum of GeV-TeV gamma-ray spectrum and more extended gamma-ray spatial radial profile than that in the X-ray band. Based on the diffusion shock acceleration model, we solve spherically symmetric hydrodynamic equations and transport equations of particles, and investigate multi-band non-thermal emission of RX J1713.7-3946 and radial profiles of its surface brightness for two selected zones in the leptonic scenario for the $\gamma$-ray emission. We found (1) the diffusion coefficient has a weak energy-dependent, and the Kolmogorov type is favored; (2) the magnetic field strength could vary linearly or nonlinearly with radius for different surrounding environments because of possible turbulence in shock downstream region, and a compressional amplification is likely to exist at the shock front; (3) the non-thermal photons from radio to X-ray bands are dominated by synchrotron emission from relativistic electrons, if the GeV-TeV gamma-rays are produced by inverse Compton scattering from these electrons interacting with the background photons, then the X-ray and gamma-ray radial profiles can be reproduced except for the more extended $\gamma$-ray emission., Comment: 30 pages, 5 figures

We present systematic X-ray spectral and variability analyses for the narrow-line Seyfert 1 galaxy (NLsy1), PG 1448+273, using the data from two long-exposureXMM-Newtonobservations of the source in the different flux states. These X-ray spectral analyses indicate that the two main-stream models of soft X-ray excess, the relativistically smeared reflection scenario and the warm corona scenario, show a similar statistical fit to the data sets. However, the warm corona scenario requires a black hole mass that is much larger than that estimated by the single-epoch optical spectroscopy and the X-ray variability scaling technology to alleviate the conflict between the X-ray and optical/ultraviolet data. The time-varying analyses reveal that PG 1448+273 has significant X-ray variability, especially in the low state. The features of X-ray spectra and variability show significant differences between the high and low states. At the low state, a highly variable ultra-fast outflow feature appears in the X-ray spectra, and the X-ray spectra show a very significant soft X-ray excess. At the high state, a ‘dip’, or oscillation, feature with ∼3.2σconfidence level emerges in the power spectral density atν ∼ 103.6Hz, which is a unique time signature of the reflected X-ray reprocessing. Meanwhile, we also detect a tentative soft lag. It is shown that these unique spectral features and variation behaviours can be explained self-consistently in the relativistically smeared reflection scenario, in which the geometric position of the corona changes. Our results suggest that PG 1448-273 can be used as an ideal object to further study the details of the relativistic reflection process.

The bright TeV source HESS J1640-465 is positionally coincident with the young SNR G338.3-0.0, and the nearby HESS J1641-463 with TeV gamma-ray emission seems to be closely associated with it. Based on the nonlinear diffusion shock acceleration (NLDSA) model, we explore the emission from these two TeV sources, the particle diffusion is assumed to be different inside and outside the absorbing boundary of the particles accelerated in the SNR shock. The results indicate that (1) the GeV to TeV emission from the region of the HESS J1640-465 is produced as a result of the particle acceleration inside the SNR G338.3-0.0; and (2) the runaway cosmic-ray particles outside the SNR are interacting with nearby dense molecular cloud (MC) at the region of the HESS J1641-463, corresponding $\pi^0$ decay gamma-ray in proton-proton collision contribute to the TeV emission from the HESS J1641-463. Also we investigate the possible X-ray emission in molecular cloud from synchrotron procedure by secondary $e^\pm$ produced through escaped protons interaction with the MC., Comment: 9 pages, 6 figures