Related papers: The Galactic 26Al Problem and The Close Binary SNI…
The discovery of the nearest young supernova remnant RXJ0852-4622/GROJ0852-4642 in the Galaxy by ROSAT and COMPTEL has been reported recently. Age and distance are determined to ~680 years and ~200 pc by the X-ray diameter and the gamma-ray…
Recent studies of supernova remnants (SNRs) have revealed that some SNRs exhibit a neutral iron line emission at 6.4 keV. This line has been proposed to originate from the interaction of high-energy particles formed in the SNR shell with…
We present new $^{26}$Al stellar yields from rotating Wolf--Rayet stellar models which, at solar metallicity, well reproduce the observed properties of the Wolf-Rayet populations. These new yields are enhanced with respect to non--rotating…
The Milky Way Galaxy glows with the soft gamma ray emission resulting from the annihilation of $\sim 5 \times 10^{43}$ electron-positron pairs every second. The origin of this vast quantity of antimatter and the peculiar morphology of the…
Wolf-Rayet (WR) stars are the evolved descendants of massive O-type stars and are considered to be progenitor candidates for Type Ib/c core-collapse supernovae (SNe). Recent results of our HST/WFC3 survey of Wolf-Rayet stars in M101 are…
The discovery of a binary neutron star merger (NSM) through both its gravitational wave and electromagnetic emission has revealed these events to be key sites of r-process nucleosynthesis. Here, we evaluate the prospects of finding the…
The association of broad-lined Type Ic supernovae with long-duration gamma-ray bursts (GRBs) has been known for 28 years. However, only about seventy gamma-ray burst supernovae (GRB-SNe) have been identified, of which only half have…
We have spectroscopically discovered a pair of twin, nitrogen-type, hydrogen-rich, Wolf-Rayet stars (WN8-9h) that are both surrounded by circular, mid-infrared-bright nebulae detected with the Spitzer Space Telescope and MIPS instrument.…
Using the Very Large Telescope's Spectrograph for INtegral Field Observation in the Near-Infrared (VLT/SINFONI), we have obtained repeated AO-assisted, NIR spectroscopy of the six central luminous, Wolf-Rayet (WR) stars in the core of the…
NIR K band imaging spectroscopy of the central 8'' (1.3 kpc) in the Wolf-Rayet LINER galaxy NGC6764 shows that the most recent star formation is most likely still unresolved at sub-arcsecond resolution (< 100pc). The continuum source has a…
Massive stars are one of the most important and investigated astrophysical production sites of $^{26}$Al, a short-lived radioisotope with $\sim$ 1 Myr half-life. Its short lifetime prevents us from observing its complete chemical history,…
Short lived radionuclides (SLRs) like $^{26}$Al are synthesized by massive stars and are a byproduct of star formation. The abundances of SLRs in the gas of a star-forming galaxy are inversely proportional to the gas consumption time. The…
The supernova remnant (SNR) W51C is a Galactic object located in a strongly inhomogeneous interstellar medium with signs of an interaction of the SNR blast wave with dense molecular gas. Diffuse X-ray emission from the interior of the SNR…
We propose that the emission of the high excitation [OIV] line observed with ISO in NGC 5253 and II Zw 40 is due to the presence of hot Wolf-Rayet (WR) stars in these objects. We construct a consistent evolutionary synthesis and…
Infrared imaging of the colliding-wind binary Apep has revealed a spectacular dust plume with complicated internal dynamics that challenges standard colliding-wind binary physics. Such challenges can be potentially resolved if a…
WR 20a is the most massive close-in binary known in our Galaxy. It is composed of two $\approx$80 M$_\odot$ Wolf-Rayet stars with a short period of $\approx$3.7 days in the open cluster Westerlund 2. As such, WR 20a presents us with a…
X-ray and near-IR surveys of the central 2x0.8 degrees of the Galactic Centre have revealed a population of X-ray bright massive stars. However, the nature of the emission, originating in a wind collision zone or via accretion onto a…
We report a multi-wavelength study of the Wolf Rayet (WR) star: [KSF2015] 1381-19L, which is located in the solar metallicity region (Z=0.014) of the Milky Way Galaxy, strongly obscured by the interstellar dust. We perform a detailed…
The explosive fate of massive stripped Wolf-Rayet (W-R) stars is a key open question in stellar physics. An appealing option is that hydrogen-deficient W-R stars are the progenitors of some H-poor supernova (SN) explosions of Types IIb, Ib,…
The Cosmic Gamma-ray Background (CGB) in the MeV region is believed to be due to photons from radioactivity produced in SNe throughout the history of galaxies in the universe. In particular, gamma-ray line emission from the decay chain…