UVSOR Lunch Seminar (2003-02)

日時:October 2nd (Thursday)16:00〜17:00(incl. discussion)
場所:UVSOR build. #304 (User's room)

Speaker: Dr. G. Lawrence Carr (NSLS - Brookhaven National Laboratory, USA)

Title: Characteristics of Far-infrared and THz Synchrotron Radiation
at the National Synchrotron Light Source

Relativistic electrons, whether in storage rings or linear accelerators
(linacs), can produce synchrotron radiation over the very broad spectral
range from x-rays down to the far-infrared and beyond. The far-infrared
spectral range has a long history for the study of solids (e.g., electronic
properties, superconductivity, lattice vibrations, and other collective
excitations) and gases (rotational/vibrational spectroscopy). Large and
complex biomolecules also show spectral features in the far-infrared, but
their relationship to their biological function (if any) is not clear.
Though many synchrotron facilities have constructed infrared beamlines,
only a few have managed to achieve good performance in the very far-infrared.

In special cases (such as in linacs) the radiating electrons can be
compressed into short bunches that radiate coherently, leading to an
enormous enhancement in the far-IR . The characteristics of this radiation
are analogous to the THz pulses produced by laser methods, except that the
intensity can be much higher. This presentation will describe the
far-infrared beamlines at the NSLS VUV ring, performance characteristics,
and some applications in materials science. It will also describe some
recent results in NSLS linac-produced coherent THz pulses.