IPG Photonics

About: IPG Photonics is a based out in . It is known for research contribution in the topics: Laser & Fiber laser. The organization has 903 authors who have published 1241 publications receiving 63339 citations.

Moho topography beneath the Corinth Rift area (Greece) from inversion of gravity data

Abstract: SUMMARY Our aim is to understand better the rifting process by imaging the Moho depth variation beneath Corinth and Evvia. We present here the results of a gravity inversion analysis in the region of the Corinth and Evvia rift system, and compare them to those obtained independently from teleseismic tomography and receiver function analyses. The results of these different studies appear to be consistent and show (1) a 10 km crustal thickening in the western part of the area beneath the Hellenides mountains, (2) NW–SE-trending periodic crustal thinning, and (3) a maximum crustal thinning north of the Gulf of Corinth. This 4 km thinning is unlikely to be the result of the rifting alone, which seems to have been reactivated since only 1 Ma. We propose here a geodynamical scenario in two major steps to explain the evolution of Corinth area. Aegean Miocene extension involving boudinage resulted in periodic crustal thinning, consistent with observations. These lithospheric instabilities could have favoured rupture initiation in particular areas, especially near the city of Corinth. Then, the reactivation of the Corinth Rift extension, 1 Myr ago, led to westward rift propagation. The offset observed between the maximum crustal thinning and the Gulf of Corinth could be accommodated by a lowangle normal fault at about 10–15 km depth. The Corinth Rift is thus asymmetrical and was initiated in places of crustal weakness due to Miocene lithospheric instabilities.

Globally aligned photomosaic of the Lucky Strike hydrothermal vent field (Mid‐Atlantic Ridge, 37°18.5′N): Release of georeferenced data, mosaic construction, and viewing software

Abstract: [1] We present a georeferenced photomosaic of the Lucky Strike hydrothermal vent field (Mid-Atlantic Ridge, 37°18′N). The photomosaic was generated from digital photographs acquired using the ARGO II seafloor imaging system during the 1996 LUSTRE cruise, which surveyed a ∼1 km2 zone and provided a coverage of ∼20% of the seafloor. The photomosaic has a pixel resolution of 15 mm and encloses the areas with known active hydrothermal venting. The final mosaic is generated after an optimization that includes the automatic detection of the same benthic features across different images (feature-matching), followed by a global alignment of images based on the vehicle navigation. We also provide software to construct mosaics from large sets of images for which georeferencing information exists (location, attitude, and altitude per image), to visualize them, and to extract data. Georeferencing information can be provided by the raw navigation data (collected during the survey) or result from the optimization obtained from image matching. Mosaics based solely on navigation can be readily generated by any user but the optimization and global alignment of the mosaic requires a case-by-case approach for which no universally software is available. The Lucky Strike photomosaics (optimized and navigated-only) are publicly available through the Marine Geoscience Data System (MGDS, http://www.marine-geo.org). The mosaic-generating and viewing software is available through the Computer Vision and Robotics Group Web page at the University of Girona (http://eia.udg.es/∼rafa/mosaicviewer.html).

Late Quaternary kinematics of the Pallatanga strike-slip fault (Central Ecuador) from topographic measurements of displaced morphological features

Abstract: The northeast-trending Pallatanga right-lateral strike-slip fault runs across the Western Cordillera connecting N50°E-N70°E trending normal faults in the Gulf of Guayaquil with N-S reverse faults in the Interandean Depression Over most of its length, the fault trace has been partly obscured by erosional processes and can be inferred in the topography only at the large scale Only the northern fault segment, which follows the upper Rio Pangor valley at elevations above 3600 m, is prominent in the morphology Valleys and ridges cut and offset by the fault provide an outstanding record of right-lateral cumulative fault displacement The fault geometry and kinematics of this particular fault segment can be determined from detailed topographic levellings The fault strikes N30°E and dips 75° to the NW Depending on their size and nature, transverse morphological features such as tributaries of the Rio Pangor and intervening ridges, reveal right-lateral offsets which cluster around 27 ± 11m, 415 ± 4 m, 590 ± 65 m and 960 ± 70 m The slip vector deduced from the short-term offsets shows a slight reverse component with a pitch of about 115° SW The 415 ± 4 m displacements are assumed to be coeval with the last glacial termination, yielding a mean Holocene slip-rate of 29- 46 mm yr^(−1) Assuming a uniform slip rate on the fault in the long term, the 27 m offset appears to correlate with an identified middle Holocene morphoclimatic event, and the long term offsets of 590 m and 960 m coincide with the glacial terminations at the beginning of the last two interglacial periods

All-Fiber Format Compression of Frequency Chirped Pulses in Air-Guiding Photonic Crystal Fibers

Abstract: Air-cored, photonic band-gap crystal fibers exhibiting low nonlinearity and anomalous chromatic dispersion in spectral ranges inaccessible to conventional fibers can be used in the realization of all-fiber-format pulse compressors with unprecedented peak powers and wavelength diversity. Linear compression of inherently chirped and prestretched pulses by factors ranging from 20 to 80 around 1.0 and 1.5 microm have allowed generation of pulses as short as 163 fs. The results show that totally integrated femtosecond fiber laser sources can be realized throughout the visible and near-infrared and point to the possibility of megawatt peak and tens of watt average in-fiber power levels.