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G Sarri,
A Macchi, C A Cecchetti,
S Kar,
T V Liseykina,
X H Yang,
M E Dieckmann,
J Fuchs,
M Galimberti,
L A Gizzi,
R Jung,
I Kourakis,
J Osterholz,
F Pegoraro,
A P L Robinson,
L Romagnani,
O Willi,
M Borghesi
[show abstract]
[hide abstract]
ABSTRACT: The dynamics of magnetic fields with an amplitude of several tens of megagauss, generated at both sides of a solid target irradiated with a high-intensity (∼10^{19} W/cm^{2}) picosecond laser pulse, has been spatially and temporally resolved using a proton imaging technique. The amplitude of the magnetic fields is sufficiently large to have a constraining effect on the radial expansion of the plasma sheath at the target surfaces. These results, supported by numerical simulations and simple analytical modeling, may have implications for ion acceleration driven by the plasma sheath at the rear side of the target as well as for the laboratory study of self-collimated high-energy plasma jets.
Physical Review Letters 11/2012; 109(20):205002. · 7.37 Impact Factor
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G. Sarri,
M. Borghesi, C. A. Cecchetti,
L. Romagnani,
R. Jung,
O. Willi,
D. J. Hoarty,
R. M. Stevenson,
C. R.D. Brown,
S. F. James,
P. Hobbs,
J. Lockyear,
S. V. Bulanov,
F. Pegoraro
[show abstract]
[hide abstract]
ABSTRACT: Multi-Mev proton beams generated by target normal sheath acceleration (TNSA) during the interaction of an ultra intense laser
beam (I≥1019W/cm2) with a thin metallic foil (thickness of
the order of a few tens of microns) are particularly suited as a particle probe for laser plasma experiments. The proton imaging
technique employs a laser-driven proton beam in a point-projection imaging scheme as a diagnostic tool for the detection of
electric fields in such experiments.
The proton probing technique has been applied in experiments of relevance to inertial confinement fusion (ICF)
such as laser heated gasbags and laser-hohlraum experiments. The data provides direct information on the onset of laser beam
filamentation and on the plasma expansion in the hohlraum’s interior, and confirms the suitability and usefulness of this
technique as an ICF diagnostic.
The European Physical Journal D 04/2012; 55(2):299-303. · 1.48 Impact Factor
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L. A. Gizzi,
A. Bacci,
S. Betti, C. A. Cecchetti,
M. Ferrario,
A. Gamucci,
A. Giulietti,
D. Giulietti,
P. Koester,
L. Labate,
T. Levato,
V. Petrillo,
L. Serafini,
P. Tomassini,
C. Vaccarezza
[show abstract]
[hide abstract]
ABSTRACT: In this paper we discuss recent results in the design configuration and modelling of the PLASMON-X project aimed at the development
of an innovative, high-gradient acceleration with super-intense and ultra-short laser pulses, and a tuneable, hard X/γ-ray
source, based upon Thomson scattering of optical photons by energetic electrons. Both experiments require very high power,
ultra-short laser pulses in combination with very bright and short electron bunches generated either by conventional acceleration
(LINAC) or by laser-driven, self injection acceleration in plasmas. The main issues concerning the integrated use of unique
laser and linear accelerator installations, and the complementary use of all-optical configurations will be briefly examined.
The European Physical Journal Special Topics 04/2012; 175(1):3-10. · 1.56 Impact Factor
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M. Borghesi,
T. Toncian,
J. Fuchs, C. A. Cecchetti,
L. Romagnani,
S. Kar,
K. Quinn,
B. Ramakrishna,
P. A. Wilson,
P. Antici, [......],
A. Pipahl,
R. Jung,
M. Amin,
O. Willi,
R. J. Clarke,
M. Notley,
P. Mora,
T. Grismayer,
E. D’Humières,
Y. Sentoku
[show abstract]
[hide abstract]
ABSTRACT: The acceleration of high-energy ion beams following the interaction of short (t < 1 ps) and intense (Iλ2 > 1018 W cm-2 μm2) laser pulses with solid targets is a field of research currently attracting high interest in the scientific community, due
to some of the unique properties of these ion sources, promising routes toward the optimization of their energy content, and
a number of possible, innovative applications in the scientific, technological and medical areas. Work on the characterization
and development of these sources has progressed enormously over the past few years, thanks to the contribution of many groups
worldwide. This paper will report some recent results, obtained in experiments carried out at the RAL and LULI laboratories,
in which we investigated the ion acceleration mechanism, developed a technique to control the ion beam divergence and energy
spectrum, and applied a proton radiography technique to investigate electric and magnetic field production following laser-matter
interaction.
The European Physical Journal Special Topics 04/2012; 175(1):105-110. · 1.56 Impact Factor
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P. Antici,
J. Fuchs,
M. Borghesi,
T. Grismayer,
S. Atzeni, C. A. Cecchetti,
L. Gremillet,
A. Mancic,
P. Mora,
A. C. Pipahl,
A. Schiavi,
T. Toncian,
O. Willi,
P. Audebert
[show abstract]
[hide abstract]
ABSTRACT: We have used time and space resolved interferometry to measure the dynamics of a plasma expanding off the surface of a solid
target. This allows accessing 1) the time- and space-resolved dynamics of the fast electrons (laser-accelerated from solids
and expanding into vacuum from the rear target surface), and of the energy partition into bulk (cold) electrons and 2) the
expansion velocity of an isochorically heated target, from which information about the heating process can be retrieved.
The European Physical Journal Special Topics 04/2012; 175(1):139-142. · 1.56 Impact Factor
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S N Chen,
E d'Humières,
E Lefebvre,
L Romagnani,
T Toncian,
P Antici,
P Audebert,
E Brambrink, C A Cecchetti,
T Kudyakov,
A Pipahl,
Y Sentoku,
M Borghesi,
O Willi,
J Fuchs
[show abstract]
[hide abstract]
ABSTRACT: The dynamics of the focusing of laser-driven ion beams produced from concave solid targets was studied. Most of the ion beam energy is observed to converge at the center of the cylindrical targets with a spot diameter of 30 μm, which can be very beneficial for applications requiring high beam energy densities. Also, unbalanced laser irradiation does not compromise the focusability of the beam. However, significant filamentation occurs during the focusing, potentially limiting the localization of the energy deposition region by these beams at focus. These effects could impact the applicability of such high-energy density beams for applications, e.g., in proton-driven fast ignition.
Physical Review Letters 02/2012; 108(5):055001. · 7.37 Impact Factor
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Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment 01/2012; 680:103-107. · 1.21 Impact Factor
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17TH INTERNATIONAL CONFERENCE ON ATOMIC PROCESSES IN PLASMAS (ICAPIP); 01/2012
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IEEE Transactions on Plasma Science 11/2011; 39(11, Part 1, SI):2954-2955. · 1.17 Impact Factor
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G Sarri,
S Kar,
L Romagnani,
S V Bulanov, C A Cecchetti,
M Galimberti,
L A Gizzi,
R Heathcote,
R Jung,
I Kourakis,
J Osterholz,
A Schiavi,
O Willi,
M Borghesi
Physics of Plasmas 08/2011; 18(8). · 2.15 Impact Factor
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G Sarri, C A Cecchetti,
R Jung,
P Hobbs,
S James,
J Lockyear,
R M Stevenson,
D Doria,
D J Hoarty,
O Willi,
M Borghesi
[show abstract]
[hide abstract]
ABSTRACT: The onset of filamentation, following the interaction of a relatively long (τ(L)≃1 ns) and intense (I(L)≃5×10(14) W/cm(2)) laser pulse with a neopentane filled gas bag target, has been experimentally studied via the proton radiography technique, in conditions of direct relevance to the indirect drive inertial confinement fusion scheme. The density gradients associated with filamentation onset have been spatially resolved yielding direct and unambiguous evidence of filament formation and quantitative information about the filamentation mechanism in agreement with previous theoretical modelings. Experimental data confirm that, once spatially smoothed laser beams are used, filamentation is not a relevant phenomenon during the heating laser beams propagation through typical hohlraum gas fills.
Physical Review Letters 03/2011; 106(9):095001. · 7.37 Impact Factor
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DIODE-PUMPED HIGH ENERGY AND HIGH POWER LASERS ELI: ULTRARELATIVISTIC LASER-MATTER INTERACTIONS AND PETAWATT PHOTONICS AND HIPER: THE EUROPEAN PATHWAY TO LASER ENERGY; 01/2011
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N C Pathak, C A Cecchetti,
A Gamucci,
A Giulietti,
D Giulietti,
P Koester,
L Labate,
T Levato,
L Nizzoli,
F Piastra,
L A Gizzi
Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment 01/2011; 653(1):126-129. · 1.21 Impact Factor
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C A Cecchetti,
A Giulietti,
P Koester,
L Labate,
T Levato,
L A Gizzi,
L Antonelli,
A Patria,
D Batani,
M Kozlova,
D Margarone,
J Nejdl,
B Rus,
M Sawicka,
M Lafon,
X Ribeyre,
G Schurtz
DIODE-PUMPED HIGH ENERGY AND HIGH POWER LASERS ELI: ULTRARELATIVISTIC LASER-MATTER INTERACTIONS AND PETAWATT PHOTONICS AND HIPER: THE EUROPEAN PATHWAY TO LASER ENERGY; 01/2011
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P Valente,
F Anelli,
A Bacci,
D Batani,
M Bellaveglia,
R Benocci,
C Benedetti,
L Cacciotti, C A Cecchetti,
A Clozza, [......],
V Lollo,
P Londrillo,
S Martellotti,
E Pace,
N Pathak,
A Rossi,
F Tani,
L Serafini,
G Turchetti,
C Vaccarezza
Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment 01/2011; 653(1):42-46. · 1.21 Impact Factor
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L Romagnani,
A Bigongiari,
S Kar,
S V Bulanov, C A Cecchetti,
T Zh Esirkepov,
M Galimberti,
R Jung,
T V Liseykina,
A Macchi,
J Osterholz,
F Pegoraro,
O Willi,
M Borghesi
[show abstract]
[hide abstract]
ABSTRACT: Slowly evolving, regularly spaced patterns have been observed in proton projection images of plasma channels drilled by intense (≳10¹⁹ W cm⁻²) short (∼1 ps) laser pulses propagating in an ionized gas jet. The nature and geometry of the electromagnetic fields generating such patterns have been inferred by simulating the laser-plasma interaction and the following plasma evolution with a two-dimensional particle-in-cell code and the probe proton deflections by particle tracing. The analysis suggests the formation of rows of magnetized soliton remnants, with a quasistatic magnetic field associated with vortexlike electron currents resembling those of magnetic vortices.
Physical Review Letters 10/2010; 105(17):175002. · 7.37 Impact Factor
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M. Borghesi,
G. Sarri, C.A. Cecchetti,
I. Kourakis,
D. Hoarty,
R.M. Stevenson,
S. James,
C.D. Brown,
P. Hobbs,
J. Lockyear,
J. Morton,
O. Willi,
R. Jung,
M. Dieckmann
[show abstract]
[hide abstract]
ABSTRACT: Proton radiography using laser-driven sources has been developed as a diagnostic since the beginning of the decade, and applied successfully to a range of experimental situations. Multi-MeV protons driven from thin foils via the Target Normal Sheath Acceleration mechanism, offer, under optimal conditions, the possibility of probing laser-plasma interactions, and detecting electric and magnetic fields as well as plasma density gradients with ~ps temporal resolution and ~ 5–10 µm spatial resolution. In view of these advantages, the use of proton radiography as a diagnostic in experiments of relevance to Inertial Confinement Fusion is currently considered in the main fusion laboratories. This paper will discuss recent advances in the application of laser-driven radiography to experiments of relevance to Inertial Confinement Fusion. In particular we will discuss radiography of hohlraum and gasbag targets following the interaction of intense ns pulses. These experiments were carried out at the HELEN laser facility at AWE (UK), and proved the suitability of this diagnostic for studying, with unprecedented detail, laser-plasma interaction mechanisms of high relevance to Inertial Confinement Fusion. Non-linear solitary structures of relevance to space physics, namely phase space electron holes, have also been highlighted by the measurements. These measurements are discussed and compared to existing models.
Laser and Particle Beams 05/2010; 28(02):277 - 284. · 1.62 Impact Factor
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G Sarri, C A Cecchetti,
L Romagnani,
C M Brown,
D J Hoarty,
S James,
J Morton,
M E Dieckmann,
R Jung,
O Willi,
S V Bulanov,
F Pegoraro,
M Borghesi
[show abstract]
[hide abstract]
ABSTRACT: Plasma expansion following the interaction of an intense laser beam with the inner surface of gold hohlraums, emulating conditions relevant to indirect drive inertial confinement fusion (ICF), has been investigated by a radiographic technique which employs a beam of laser-accelerated protons. This probing technique has made it possible to measure the electric field distribution associated with the plasma front and its propagation throughout the interior of the hohlraum with a temporal and spatial resolution of the order of a few ps and μm, respectively. The data indicate that the expanding plasma slows down approaching the opposite walls, possibly due to the interaction with x-ray heated plasma from the non-irradiated walls. The electric field at the plasma front shows a bipolar structure, suggesting the presence of ion-acoustic soliton-like structures cotraveling with the front. Data obtained using enclosed hohlraums suggest the feasibility of this type of diagnosis in gas-filled hohlraums, as currently employed in ICF experiments.
New Journal of Physics 04/2010; 12(4):045006. · 4.18 Impact Factor
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R Faccini,
F. Anelli,
A Bacci,
D Batani,
M Bellaveglia,
R. Benocci,
C. Benedetti,
L. Cacciotti, C A Cecchetti,
A. Clozza, [......],
P. Londrillo,
S. Martellotti,
E. Pace,
N. Patack,
A Rossi,
F. Tani,
L. Serafini,
G. Turchetti,
C. Vaccarezza,
P. Valente
[show abstract]
[hide abstract]
ABSTRACT: The advance in laser plasma acceleration techniques pushes the regime of the resulting accelerated particles to higher energies and intensities. In particular the upcoming experiments with the FLAME laser at LNF will enter the GeV regime with almost 1pC of electrons. From the current status of understanding of the acceleration mechanism, relatively large angular and energy spreads are expected. There is therefore the need to develop a device capable to measure the energy of electrons over three orders of magnitude (few MeV to few GeV) under still unknown angular divergences. Within the PlasmonX experiment at LNF a spectrometer is being constructed to perform these measurements. It is made of an electro-magnet and a screen made of scintillating fibers for the measurement of the trajectories of the particles. The large range of operation, the huge number of particles and the need to focus the divergence present unprecedented challenges in the design and construction of such a device. We will present the design considerations for this spectrometer and the first results from a prototype. Comment: 7 pages, 6 figures, submitted to NIM A
02/2010;
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C A Cecchetti,
S Betti,
A Gamucci,
A Giulietti,
D Giulietti,
P Koester,
L Labate,
N Patak,
F Vittori,
O Ciricosta,
L A Gizzi
2ND INTERNATIONAL CONFERENCE ON ULTRA-INTENSE LASER INTERACTION SCIENCE; 01/2010
