ﻻ يوجد ملخص باللغة العربية
Non-thermal hard X-ray and high-energy (HE; 1 MeV < E < 100 GeV) gamma-ray emission in the direction of Eta Carina has been recently detected using the INTEGRAL, AGILE and Fermi satellites. So far this emission has been interpreted in the framework of particle acceleration in the colliding wind region between the two massive stars. However, the existence of a very fast moving blast wave which originates in the historical 1843 Great Eruption provides an alternative particle acceleration site in this system. Here we explore an alternate scenario and find that inverse Compton emission from electrons accelerated in the blast wave can naturally explain both the flux and spectral shape of the measured hard X-ray and HE gamma-ray emission. This scenario is further supported by the lack of significant variability in the INTEGRAL and Fermi measured fluxes.
During the years 1838-1858, the very massive star {eta} Carinae became the prototype supernova impostor: it released nearly as much light as a supernova explosion and shed an impressive amount of mass, but survived as a star.1 Based on a light-echo s
Non-relativistic shocks accelerate ions to highly relativistic energies provided that the orientation of the magnetic field is closely aligned with the shock normal (quasi-parallel shock configuration). In contrast, quasi-perpendicular shocks do not
In our ongoing study of eta Carinaes light echoes, there is a relatively bright echo that has been fading slowly, reflecting the 1845-1858 plateau of the eruption. A separate paper discusses its detailed evolution, but here we highlight one important
We present follow-up optical imaging and spectroscopy of one of the light echoes of $eta$ Carinaes 19th-century Great Eruption discovered by Rest et al. (2012). By obtaining images and spectra at the same light echo position between 2011 and 2014, we
Aims. Every 5.5 years eta Cars light curve and spectrum change remarkably across all observed wavelength bands. We compare the recent spectroscopic event in mid-2014 to the events in 2003 and 2009 and investigate long-term trends. Methods. Eta Car wa