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Optical observations of γ-ray burst (GRB) 060614 (duration ∼100s) rule out the presence of an associated supernova. This would seem to require a new explosive process: either a massive 'collapsar' that powers a GRB without any associated supernova, or a new type of engine, as long-lived as the collapsar but without a massive star.
GRB 060505 and GRB 060614 were not accompanied by supernova emission down to limits hundreds of times fainter than the archetypal SN 1998bw that accompanied GRB 980425, and fainter than any type Ic supernova ever observed.
Deep optical observations of GRB 060614 show no emerging supernova with absolute magnitude brighter than MV = − 13.7. Any supernova associated with GRB 060614 was therefore at least 100 times fainter, at optical wavelengths, than the other supernovae associated with GRBs.
The bright, nearby γ-ray burst (GRB) 060614 does not fit in either of the two duration classes. Its ∼102-s duration groups it with long-duration GRBs, whereas its temporal lag and peak luminosity fall entirely within the short GRB subclass. This opens the door on a new GRB classification scheme that straddles both long and short bursts.
The observation of the radiative decay mode of free neutrons, with measurements that agree with theoretical predictions may provide opportunities for more detailed investigations of the weak interaction processes involved neutron beta decay.
Characterization of a new human XPF mutation (XFE) that leads to profound DNA intrastrand crosslink sensitivity and progeroid symptoms is reported, indicating that the accumulation of DNA damage induces a metabolic response aimed at extending life span rather than maintaining growth.
Proteins are made of amino acids. But amino acids are made of atoms. Exploration of this self-evident principle opens up fresh perspectives on the evolution of biological membranes and multicellular life.