881 research outputs found
Letter from S. W. Colson to B. R. Colson
Letter from S. W. Colson to B. R. Colson. The three-page handwritten note is dated 8 February 1910. There is a transcript of the correspondence in the item PDF
Letter from S. W. Colson to B. R. Colson
Letter from S. W. Colson to B. R. Colson. The three-page handwritten note is dated 21 August 1907. There is a transcript of the correspondence in the item PDF
Letter from S. W. Colson to J. O. Barnes
Letter from S. W. Colson to J. O. Barnes. The one-page handwritten note is dated 24 May 1909. There is a transcript of the correspondence in the item PDF
Option contract between J. J. and Emma S. Freeze and W. W. Colson
Option contract dated 18 April 1912 between J. J. and Emma S. Freeze and W. W. Colson
Fel Oscillators with Tapered Undulators: Inclusion of Harmonic Generation and Pulse Propagation
We review the theory of FEL oscillators operating with tapered undulators. We
consider the case of a uniform tapering and introduce a parameter which
characterizes the effect of the tapering on the gain and on the saturation
intensity. We analyze the effect of the tapering on the FEL dynamics by
including the pulse propagation effects too. We analyze the importance of
tapering as a tool to model the optical pulse shapes and to control the higher
harmonic intensities
Photon emission by an ultra-relativistic particle channeling in a periodically bent crystal
This paper is devoted to a detailed analysis of the new type of the undulator
radiation generated by an ultra-relativistic charged particle channeling along
a crystal plane, which is periodically bent by a transverse acoustic wave, as
well as to the conditions limiting the observation of this phenomenon. This
mechanism makes feasible the generation of electromagnetic radiation, both
spontaneous and stimulated, emitted in a wide range of the photon energies,
from X- up to gamma-rays
The FHI FEL Upgrade Design
Since coming on-line in November 2013, the Fritz-Haber-Institut (FHI) der Max-Planck-Gesellschaft (MPG) Free-Electron Laser (FEL) has provided intense, tunable infrared radiation to FHI user groups. It has enabled experiments in diverse fields ranging from bio-molecular spectroscopy to studies of clusters and nanoparticles, nonlinear solid-state spectroscopy, and surface science, resulting in 50 peer-reviewed publications so far. The MPG has now funded a significant upgrade to the original FHI FEL. A second short Rayleigh range undulator FEL beamline is being added that will permit lasing from 160 microns. Additionally, a 500 MHz kicker cavity will permit simultaneous two-color operation of the FEL from both FEL beamlines over an optical range of 5 to 50 microns by deflecting alternate 1 GHz pulses into each of the two undulators. We will describe the upgraded FHI FEL physics and engineering design and present the plans for two-color FEL operations in November 2020
The FHI FEL Upgrade Design
Since coming on-line in November 2013, the Fritz-Haber-Institut (FHI) der Max-Planck-Gesellschaft (MPG) Free-Electron Laser (FEL) has provided intense, tunable infrared radiation to FHI user groups. It has enabled experiments in diverse fields ranging from bio-molecular spectroscopy to studies of clusters and nanoparticles, nonlinear solid-state spectroscopy, and surface science, resulting in 50 peer-reviewed publications so far. A significant upgrade of the FHI FEL is now being prepared. A second short Rayleigh range undulator FEL beamline is being added that will permit lasing from 160 microns. Additionally, a 500 MHz kicker cavity will permit simultaneous two-color operation of the FEL from both FEL beamlines over an optical range of 5 to 50 microns by deflecting alternate 1 GHz pulses into each of the two undulators. We will describe the upgraded FHI FEL physics and engineering design and present the plans for two-color FEL operations in November 2020
Supercooling of the disordered vortex lattice in Bi_2Sr_2CaCu_2O_8+d
Time-resolved local induction measurements near to the vortex lattice
order-disorder transition in optimally doped
BiSrCaCuO single crystals shows that the
high-field, disordered phase can be quenched to fields as low as half the
transition field. Over an important range of fields, the electrodynamical
behavior of the vortex system is governed by the co-existence of the two phases
in the sample. We interpret the results in terms of supercooling of the
high-field phase and the possible first order nature of the order-disorder
transition at the ``second peak''.Comment: 4 pages, 3 figures. Submitted to Nature, July 10th, 1999; Rejected
August 8th for lack of broad interest Submitted to Physical Review Letters
September 10th, 199
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