ar X iv : a st ro - p h / 07 01 06 4 v 1 3 J an 2 00 7 Modeling of the Terminal Velocities of the Dust Ejected Material by the Impact

ar X iv : a st ro - p h / 06 11 00 6 v 1 31 O ct 2 00 6 A Search for Deep Impact ’ s Large Particle Ejecta

The Deep Impact encounter with the nucleus of 9P/Tempel ejected small grains (a . 10 μm) into the comet’s coma, evidenced by thermal emission from small dust grains at mid-infrared wavelengths (λ ∼ 10 μm) and dynamical simulations of optical images. Meteor-sized particles (a & 100 μm) ejected by the impact will likely have the lowest ejection velocities and will weakly interact with solar radia...

ar X iv : a st ro - p h / 06 03 30 6 v 1 1 3 M ar 2 00 6 Deep Impact : High Resolution Optical Spectroscopy with the ESO VLT and the Keck 1 telescope

We report on observations of comet 9P/Tempel 1 carried out before, during, and after the NASA DEEP IMPACT event (UT July 4), with the optical spectrometers UVES and HIRES mounted on the telescopes Kueyen of the ESO VLT (Chile) and Keck 1 on Mauna Kea (Hawaii), respectively. A total observing time of about 60 hours, distributed over 15 nights around the impact date, allowed us (i) to find a peri...

ar X iv : a st ro - p h / 01 03 44 4 v 1 2 7 M ar 2 00 1 From Centimeter to Millimeter Wavelengths : A High Angular Resolution Study of 3 C 273

We monitored 3C 273 with VLBI at 15–86 GHz since 1990. We discuss component trajectories, opacity effects, a rotating jet, and outburst-ejection relations from Gamma-ray to radio bands.

ar X iv : a st ro - p h / 06 05 06 7 v 1 2 M ay 2 00 6 Sensitivity and pointing accuracy of the NEMO km 3 telescope

ar X iv : a st ro - p h / 06 01 61 4 v 1 2 6 Ja n 20 06 Low Carbon Abundance in Type Ia Supernovae

We investigate the quantity and composition of unburned material in the outer layers of three normal Type Ia supernovae (SNe Ia): 2000dn, 2002cr and 2004bw. Pristine matter from a white dwarf progenitor is expected to be a mixture of oxygen and carbon in approximately equal abundance. Using near-infrared (NIR, 0.7 − 2.5 µm) spectra, we find that oxygen is abundant while carbon is severely deple...