No abstract

Following earthquake initiation, most earthquake early warning (EEW) algorithms provide initial hazard predictions based on the character of the first arriving P-waves, which is the earliest information available. However, it is well known that this approach will routinely struggle during large magnitude earthquakes owing to magnitude saturation, or underestimation, a current limitation of such EEW systems. As an example of this, the Japanese EEW system misidentified the 2011 Mw9.0 Tohoku-oki earthquake as only an Mw8.1 for the first hour after rupture (Hoshiba et al., 2011). Saturation occurs for a couple of reasons. First, inertial-based instruments (seismometers) that record earthquakes in the near-field tend to distort

No abstract

No abstract

We report the observation of harmonic mode locking and multiple pulse operations in a soft-aperture Kerr-lens mode-locked Ti:sapphire laser by varying the total intra-cavity dispersion. Second, third, and fourth order harmonic mode locking as well as multiple pulsing with interpulse separation ranging from femtosecond to nanosecond are observed. The laser is characterized in these regimes in terms of wavelength, bandwidth, pulsewidth, average and peak powers as functions of group velocity dispersion. By introducing a loss difference term into gain dynamic analysis, we conclude that gain depletion and recovery mechanisms are responsible for the underlying physics of current observations.