Search Publications
The Progenitor of the Type IIb SN 2008ax Revisited
Nomoto, Ken'ichi; Folatelli, Gastón; Kuncarayakti, Hanindyo +3 more
Hubble Space Telescope observations of the site of the supernova (SN) SN 2008ax obtained in 2011 and 2013 reveal that the possible progenitor object detected in pre-explosion images was in fact multiple. Four point sources are resolved in the new, higher-resolution images. We identify one of the sources with the fading SN. The other three objects …
Imaging and Spectral Observations of Quasi-periodic Pulsations in a Solar Flare
Li, D.; Zhang, Q. M.; Ning, Z. J.
We explore the quasi-periodic pulsations (QPPs) in a solar flare observed by Fermi Gamma-ray Burst Monitor, Solar Dynamics Observatory, Solar Terrestrial Relations Observatory, and Interface Region Imaging Spectrograph (IRIS) on 2014 September 10. QPPs are identified as the regular and periodic peaks on the rapidly varying components, which are th…
Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) after nine years of operation: A summary
Gurnett, D. A.; Morgan, D. D.; Orosei, R. +13 more
Mars Express, the first European interplanetary mission, carries the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) to search for ice and water in the Martian subsurface. Developed by an Italian-US team, MARSIS transmits low-frequency, wide-band radio pulses penetrating below the surface and reflected by dielectric discontinui…
SINFONI spectra of heavily obscured AGNs in COSMOS: Evidence of outflows in a MIR/O target at z ~ 2.5
Berta, S.; Lutz, D.; Le Floc'h, E. +9 more
Aims: We present new data for four candidate obscured Compton-Thick (CT) quasars at z ~ 1-2.5 observed with the SINFONI VLT spectrograph in adaptive optics (AO) mode. These sources were selected from a 24 µm Spitzer MIPS survey of the COSMOS field, on the basis of red mid-infrared to optical and optical to near-infrared colours, with th…
Constraints on secret neutrino interactions after Planck
Lattanzi, Massimiliano; Natoli, Paolo; Forastieri, Francesco
Neutrino interactions beyond the standard model of particle physics may affect the cosmological evolution and can be constrained through observations. We consider the possibility that neutrinos possess secret scalar or pseudoscalar interactions mediated by the Nambu-Goldstone boson of a still unknown spontaneously broken global U(1) symmetry, as i…
Seasonal variation of Martian pick-up ions: Evidence of breathing exosphere
Fedorov, A.; Barabash, S.; Lundin, R. +8 more
The Mars Express (MEX) Ion Mass Analyser (IMA) found that the detection rate of the ring-like distribution of protons in the solar wind outside of the bow shock to be quite different between Mars orbital summer (around perihelion) and orbital winter (around aphelion) for four Martian years, while the north-south asymmetry is much smaller than the …
Temporal morphological changes in the Imhotep region of comet 67P/Churyumov-Gerasimenko
Jorda, L.; Lara, L. M.; Bertaux, J. -L. +45 more
Aims: We report on the first major temporal morphological changes observed on the surface of the nucleus of comet 67P/Churyumov-Gerasimenko in the smooth terrains of the Imhotep region.
Methods: We used images of the OSIRIS cameras onboard Rosetta to follow the temporal changes from 24 May 2015 to 11 July 2015.
Results: The morpholo…
Massive stars on the verge of exploding: the properties of oxygen sequence Wolf-Rayet stars
Kaper, L.; de Mink, S. E.; de Koter, A. +7 more
Context. Oxygen sequence Wolf-Rayet (WO) stars are a very rare stage in the evolution of massive stars. Their spectra show strong emission lines of helium-burning products, in particular highly ionized carbon and oxygen. The properties of WO stars can be used to provide unique constraints on the (post-)helium burning evolution of massive stars, an…
Multi-wavelength observations of the binary system PSR B1259-63/LS 2883 around the 2014 periastron passage
Krivonos, R.; Tsygankov, S.; Tomsick, J. A. +16 more
We report on the results of the extensive multi-wavelength campaign from optical to GeV γ-rays of the 2014 periastron passage of PSR B1259-63, which is a unique high-mass γ-ray emitting binary system with a young pulsar companion. Observations demonstrate the stable nature of the post-periastron GeV flare and prove the coincidence of the flare wit…
The Destruction of the Circumstellar Ring of SN 1987A
Smith, Nathan; Garnavich, Peter; Pun, Chun S. J. +23 more
We present imaging and spectroscopic observations with Hubble Space Telescope and Very Large Telescope of the ring of SN 1987A from 1994 to 2014. After an almost exponential increase of the shocked emission from the hotspots up to day ∼8000 (∼2009), both this and the unshocked emission are now fading. From the radial positions of the hotspots we s…