Abstracts Brochure - CERN

MOPCH001
MOPCH002
MOPCH003
26-Jun-06 16:00 - 18:00 MOPCH — Poster Session
MOPCH — Poster Session
Modeling Coherence Decay in Broad Band Triplet Interaction
In the present analysis we study the transi-
M. Frichembruder, R. Pakter, F.B. Rizzato (IF-UFRGS)
tion from coherent to incoherent dynamics
in a nonlinear triplet of broad band combs of
waves*. We first reduce the original set of equations into a set where all submodes within a comb interact with all
pairs of submodes in the remaining combs. We then develop a spectral formalism that in a self-contained way enables:
(i) to determine the point of the transition; (ii) to obtain a convenient set of low dimensional equations modeling the
full dynamics**. As shall be discussed in connection with accelerator physics, the results can be applied to a variety
of parametric or nonlinear wave devices like beat wave accelerators, FELs, etc.
*G. I. Oliveira et al. Physica D 164, 59 (2002).**M. Frichembruder et al. submitted to Physica. D (2005).
Seeding the FEL of the SCSS Test Facility with the 13th Laser Harmonic of a Ti: Sa Laser
Produced in Gases
G. Lambert, M. Bougeard, W. Boutu, P. Breger, B. Carré, M.-E. Couprie,
D. Garzella, M. Labat, H. Merdji, P. Monchicourt, P. Salieres
(CEA) O.V. Chubar (SOLEIL) T. Hara, H. Kitamura, T. Shintake
(RIKEN Spring-8 Harima) D. Nutarelli (LAC)
44
A seeding configuration, in which the 13th
harmonic (60 nm) of a Ti: Sa laser (50 mJ,
10 Hz, 130 fs) generated in a gas cell is used
as the external source, will be tested in 2006
on the SCSS test facility (SPring-8 Compact
Sase Source, Japan). This facility is based on
a thermionic cathode electron gun (1 nC of bunch charge), a C-band LINAC (5712 MHz, 35 MV/m) and two invacuum
undulators (15 mm of period). The maximum electron beam energy is 250 MeV and the SASE emission
from visible to 60 nm can be obtained. The High order Harmonic Generation (HHG) experiment was mounted offline
at the end of last December. A first chamber is dedicated to harmonic generation. A second one is used for
spectral selection and adaptation of the harmonic waist in the modulator. The tests are performed in Saclay with the
LUCA (Laser Ultra Court Accordable) laser (15 mJ, 10 Hz, 50 fs) from January to March at 266 nm, 160 nm and 60 nm
and its results are presented here. Also, before performing the real tests in SPring-8 FEL presence, final theoretical
estimations of the performances relying on 1D simulations using PERSEO code and 3D simulations using GENESIS
and SRW codes are given.
Seeding SPARC Facility with Harmonic Generation in Gases
M. Labat, M. Bougeard, P. Breger, B. Carré, M.-E. Couprie, D.
Garzella, G. Lambert, H. Merdji, P. Monchicourt, P. Salieres, O.
Tcherbakoff (CEA) L. Giannessi (ENEA C.R. Frascati) D. Nutarelli
(LAC)
In High Gain Harmonic Generation Free
Electron Laser configuration, an external
light source is injected in the first part of an
undulator. The electron-photon interaction
leads to a coherent light emission in the second
part of the undulator. We propose to use
the High Order Harmonic Generation in gases process as the seed for SPARC project (Frascati, Italy). With this facility,
the electron beam is accelerated to 200 MeV and passes through an undulator of 6 sections. The preliminary tests