Related papers: 26Al in the inner Galaxy
The annihilation of positrons in the Galaxy's interstellar medium produces characteristic gamma-rays with a line at 511 keV. This emission has been observed with the spectrometer SPI on INTEGRAL, confirming a puzzling morphology with bright…
The comparison of COMPTEL 1.8 MeV gamma-ray line data to an extended data base of tracer maps revealed an extremely close correlation between 1.8 MeV gamma-ray line emission on the one side and 53 GHz microwave free-free emission and 158 um…
The observation of the interstellar 1.809 MeV decay-line of radioactive 26Al by the imaging gamma-ray telescope COMPTEL have let to the conclusion, that massive stars and their subsequent core-collapse supernovae are the dominant sources of…
We report the negative results of our searches in COMPTEL data for 1.809 MeV gamma-ray line emission from four localized regions which contain nearby supernova remnants (SNRs). The upper flux limits (2 Sigma) are found to be in the range of…
Since its launch in October 2002, ESA's INTEGRAL observatory has enabled significant advances to be made in the study of Galactic nucleosynthesis. In particular, the imaging Ge spectrometer SPI combines for the first time the diagnostic…
Diffuse gamma-ray emission from the decay of radioactive $^{26}$Al is a messenger from the nucleosynthesis activity in our current-day galaxy. Because this material is attributed to ejections from massive stars and their supernovae, the…
An object discovered during an infrared survey of the field near the quasar B2 0149+33 has an emission line at 2.25$\mu$m that we interpret as H$\alpha$ at a redshift of 2.43. The K-band image shows two compact components 10 kpc apart…
Using recently calculated yields for Type II supernovae, along with models for chemical evolution and the distribution of mass in the interstellar medium, the current abundances and spatial distributions of two key gamma-ray…
The International Gamma-Ray Astrophysics Laboratory, i.e. the INTEGRAL satellite of ESA, in orbit since about 3 years, performs gamma-ray observations of the sky in the 15 keV to 8 MeV energy range. Thanks to its imager IBIS, and in…
Recent observations of the diffuse Galactic gamma-ray glow at 1.809 MeV, attributed to the radioactive decay of 26Al, point towards a massive star origin of this radioactive isotope. Wolf Rayet stars and core-collapse supernovae appear to…
The diffuse continuum emission from the Galactic plane in the energy range 18-1000 keV has been studied using 16 Ms of data from the SPI instrument on INTEGRAL. With such an exposure we can exploit the imaging properties of SPI to achieve a…
We compare the full-sky morphology of the 511 keV gamma ray excess measured by the INTEGRAL/SPI experiment to predictions of models based on dark matter (DM) scatterings that produce low-energy positrons: either MeV-scale DM that…
We have searched for the important radioactive isotope 26Al in the nova-like source V4332 Sgr. Recent results from gamma ray astronomy show that there is pervasive emission of the 1.809 MeV gamma ray photon, arising from the decay of 26Al…
High-resolution (0."03 - 0."09) (9 - 26 pc)) ALMA (100 - 350 GHz (3 - 0.8 mm)) and VLA 45 GHz measurements have been used to image continuum and spectral line emission from the inner region of the nearby infrared luminous galaxy IC 860. We…
The center of our Galaxy is a known strong source of electron-positron 511-keV annihilation radiation. Thus far, however, there have been no reliable detections of annihilation radiation outside of the central radian of our Galaxy. One of…
The SPI instrument on-board the ESA/INTEGRAL satellite is engaged in a mission-long study of positron annihilation radiation from the Galaxy. Early results suggest that the disk component is only weakly detected at 511 keV by SPI. We review…
The annihilation of cosmic positrons ($e^+$) with electrons in the interstellar medium (ISM) results in the strongest persistent gamma-ray line signal in the sky. For 50 years, this 511 keV emission has puzzled observers and theoreticians.…
We have carried out an extensive search for gamma-ray lines in the first year of public data from the Spectrometer (SPI) on the INTEGRAL mission. INTEGRAL has spent a large fraction of its observing time in the Galactic Plane with…
We derive the extinction curve towards the Galactic Center from 1 to 19 micron. We use hydrogen emission lines of the minispiral observed by ISO-SWS and SINFONI. The extinction free flux reference is the 2 cm continuum emission observed by…
Products from massive-star nucleosynthesis have been measured with SPI on INTEGRAL: Characteristic gamma-ray lines from radioactive decays of long-lived 26Al and 60Fe isotopes, and from 44Ti decay (decay time 89y). Detections of both these…