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M. Bazzi,
G. Beer,
C. Berucci,
L. Bombelli,
A. M. Bragadireanu,
M. Cargnelli,
C. Curceanu,
A. d'Uffizi,
C. Fiorini,
T. Frizzi, [......],
A. Scordo,
H. Shi,
D. L. Sirghi,
F. Sirghi,
H. Tatsuno,
A. Tudorache,
V. Tudorache,
O. Vazquez Doce,
E. Widmann,
J. Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The study of the KbarN system at very low energies plays a key role for the
understanding of the strong interaction between hadrons in the strangeness
sector. At the DAFNE electron-positron collider of Laboratori Nazionali di
Frascati we studied kaonic atoms with Z=1 and Z=2, taking advantage of the
low-energy charged kaons from Phi-mesons decaying nearly at rest. The SIDDHARTA
experiment used X-ray spectroscopy of the kaonic atoms to determine the
transition yields and the strong interaction induced shift and width of the
lowest experimentally accessible level (1s for H and D and 2p for He). Shift
and width are connected to the real and imaginary part of the scattering
length. To disentangle the isospin dependent scattering lengths of the
antikaon-nucleon interaction, measurements of Kp and of Kd are needed. We
report here on an exploratory deuterium measurement, from which a limit for the
yield of the K-series transitions was derived: Y(K_tot)<0.0143 and
Y(K_alpha)<0.0039 (CL 90%). Also, the upcoming SIDDHARTA-2 kaonic deuterium
experiment is introduced.
02/2013;
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M Bazzi,
G Beer,
L Bombelli,
A M Bragadireanu,
M Cargnelli,
C Curceanu Petrascu,
A Dʼuffizi,
C Fiorini,
T Frizzi,
F Ghio, [......],
H Shi,
D L Sirghi,
F Sirghi,
H Tatsuno,
A Tudorache,
V Tudorache,
O Vazquez Doce,
B Wünschek,
E Widmann,
J Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The kaonic (3)He and (4)He X-rays emitted in the [Formula: see text] transitions were measured in the SIDDHARTA experiment. The widths of the kaonic (3)He and (4)He 2p states were determined to be [Formula: see text], and [Formula: see text], respectively. Both results are consistent with the theoretical predictions. The width of kaonic (4)He is much smaller than the value of [Formula: see text] determined by the experiments performed in the 70's and 80's, while the width of kaonic (3)He was determined for the first time.
Physics Letters B 07/2012; 714(1):40-43. · 3.95 Impact Factor
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The SIDDHARTA collaboration,
M. Bazzi,
G. Beer,
L. Bombelli,
A. M. Bragadireanu,
M. Cargnelli,
C. Curceanu,
A. d'Uffizi,
C. Fiorini,
T. Frizzi, [......],
H. Shi,
D. L. Sirghi,
F. Sirghi,
H. Tatsuno,
A. Tudorache,
V. Tudorache,
O. Vazquez Doce,
B. Wunschek,
E. Widmann,
J. Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The kaonic 3He and 4He X-rays emitted in the 3d-2p transitions were measured
in the SIDDHARTA experiment. The widths of the kaonic 3He and 4He 2p states
were determined to be Gamma_2p(3He) = 6 \pm 6 (stat.) \pm 7 (syst.) eV, and
Gamma_2p(4He) = 14 \pm 8 (stat.) \pm 5 (syst.) eV, respectively. Both results
are consistent with the theoretical predictions. The width of kaonic 4He is
much smaller than the value of 55 \pm 34 eV determined by the experiments
performed in the 70's and 80's, while the width of kaonic 3He was determined
for the first time.
Physics Letters B 05/2012; 714:40-43. · 3.95 Impact Factor
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C. Curceanu (Petrascu,
M. Bazzi,
G. Beer,
L. Bombelli,
A. M. Bragadireanu,
M. Cargnelli,
C. Fiorini,
T. Frizzi,
F. Ghio,
B. Girolami, [......],
A. Scordo,
H. -X. Shi,
D. L. Shirghi,
F. Sirghi,
H. Soltau,
L. Struder,
H. Tatsuno,
O. Vazquez Doce,
E. Widmann,
J. Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The DAΦNE electron-positron collider at the Frascati National Laboratories has made available a unique “beam” of negative
kaons. The SIDDHARTA (SIlicon Drift Detector for Hadronic Atom Research by Timing Application) experiment, successor of DEAR
(DAΦNE Exotic Atom Research), aims at a precision measurement of the strong interaction shift and width of the fundamental
1s level, via the measurement of the x-ray transitions to this level, for kaonic hydrogen and kaonic deuterium. The final goal
is to extract the isospin dependent antikaon-nucleon scattering lengths which contribute to the understanding of aspects of
non-perturbative QCD in the strangeness sector. Other possible hadronic atoms measurements at DAΦNE are under study.
Hyperfine Interactions 05/2012; 193(1):11-17. · 0.21 Impact Factor
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C. Curceanu (Petrascu,
M. Bazzi,
G. Beer,
L. Bombelli,
A. M. Bragadireanu,
M. Cargnelli,
G. Corradi,
A. d’Uffizi,
C. Fiorini,
T. Frizzi, [......],
A. Scordo,
H. Shi,
D. L. Sirghi,
F. Sirghi,
H. Tatsuno,
A. Tudorache,
V. Tudorache,
O. Vazquez Doce,
E. Widmann,
J. Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The DAΦNE electron–positron collider at the Laboratori Nazionali di Frascati of INFN has made available a unique quality low-energy
negative kaons “beam”. The SIDDHARTA experiment used this beam to perform unprecedented precision measurements on kaonic atoms,
while the AMADEUS experiment plans to perform in the coming years precision measurements on kaon–nuclei interactions at low-energies,
in particular to study the kaonic nuclei. The two experiments are briefly presented in this paper.
Few-Body Systems 04/2012; 50(1):447-449. · 1.44 Impact Factor
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M. Bazzi,
G. Beer,
L. Bombelli,
A. M. Bragadireanu,
M. Cargnelli,
M. Catitti,
C. Curceanu (Petrascu,
C. Fiorini,
T. Frizzi,
F. Ghio, [......],
V. Lucherini,
D. Pietreanu,
T. Ponta,
D. L. Sirghi,
F. Sirghi,
H. Soltau,
L. Strüder,
O. Vazquez Doce,
E. Widmann,
J. Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The DEAR experiment performed at the DAΦNE electron-positron collider (Frascati, Italy) studied the strong interaction shift
and width of the 1s state in kaonic hydrogen using X-ray spectroscopy. The repulsive character of the kaon-proton interaction at threshold was
confirmed and the most precise values of the shift and width were obtained. However, high precision data at the percent level
are highly requested to further develop the theories and thus our understanding of the low-energy antikaon-nucleon interaction.
Therefore, a new series of precision experiments on kaonic hydrogen and kaonic deuterium are planned at LNF.
Few-Body Systems 04/2012; 44(1):79-82. · 1.44 Impact Factor
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M. Bazzi,
G. Beer,
L. Bombelli,
A. M. Bragadireanu,
M. Cargnelli,
G. Corradi,
C. Curceanu,
A. d'Uffizi,
C. Fiorini,
T. Frizzi, [......],
A. Scordo,
H. Shi,
D. L. Sirghi,
F. Sirghi,
H. Tatsuno,
A. Tudorache,
V. Tudorache,
O. Vazquez Doce,
E. Widmann,
J. Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: Kaonic hydrogen atoms provide a unique laboratory to probe the kaon-nucleon
strong interaction at the energy threshold, allowing an investigation of the
interplay between spontaneous and explicit chiral symmetry breaking in
low-energy QCD. The SIDDHARTA Collaboration has measured the $K$-series X rays
of kaonic hydrogen atoms at the DA$\Phi$NE electron-positron collider of
Laboratori Nazionali di Frascati, and has determined the most precise values of
the strong-interaction induced shift and width of the $1s$ atomic energy level.
This result provides vital constraints on the theoretical description of the
low-energy $\bar{K}N$ interaction.
01/2012;
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[show abstract]
[hide abstract]
ABSTRACT: In this paper, mechanical and electrical nonlinearities of MEMS resonators are discussed and their influence on the resonant sensing performance is analyzed. An “L-shaped” resonator is proposed in order to reduce the influence of the nonlinear mechanical term on the global response with respect to the more standard clamped-clamped (“I-shaped”) resonator. An extended linear behavior of the “L-shaped” resonator is analytically demonstrated and validated through experimental results. As a consequence, the proposed resonator can be driven to larger vibration amplitudes through higher actuation voltages, allowing better signal-to-noise ratio (SNR).
IEEE Sensors Journal 01/2012; · 1.52 Impact Factor
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M. Cargnelli,
M. Bazzi,
G. Beer,
L. Bombelli,
A. M. Bragadireanu,
C. Curceanu,
C. Fiorini,
T. Frizzi,
F Ghio,
B. Girolami, [......],
A. Scordo,
H.‐ X. Shi,
D. L. Sirghi,
F Sirghi,
H. Soltau,
L. Strüder,
H. Tatsuno,
O. Vazquez Doce,
E. Widmann,
J. Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The KN system at rest makes a sensitive testing ground for low energy QCD. At the DAΦNE electron‐positron collider of Laboratori Nazionali di Frascati we study kaonic atoms, taking advantage of the low‐energy kaons from Φ‐mesons decaying nearly at rest. The DEAR (DAΦNE Exotic Atom Research) experiment at LNF delivered the most precise data on kaonic hydrogen up to now. DEAR and its follow‐up experiment SIDDHARTA (Silicon Drift Detector for Hadronic Atom Research by Timing Application) are using X‐ray spectroscopy of kaonic atoms to measure the strong interaction induced shift and width of the ground state. SIDDHARTA is the first experiment on kaonic helium‐3 and deuterium ever, and kaonic hydrogen was remeasured with improved precision.
AIP Conference Proceedings. 10/2011; 1374(1):212-215.
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[show abstract]
[hide abstract]
ABSTRACT: We present a monolithic CMOS charge preamplifier named “CUBE”. It is specifically designed to be used with Silicon Drift Detectors (SDD). We will show that the use a MOSFET as input transistor allows superior noise performances at very short shaping times respect to the state-of-the-art externally connected JFET devices. We will show the achievable energy resolutions using a 10mm2 reference SDD with different count-rates and with different analog and digital commercial filters. A state-of-the-art energy resolution (for a silicon detector) of 125 eV at 6 keV has been achieved with the optimum shaping time. Moreover, it will be shown that CUBE enables the use of an extremely fast-peaking time of only 100 ns with extraordinary good energy resolution of 149 eV. As a consequence we can state that, the CUBE preamplifier is very well suited for high count-rate spectroscopy applications. An example of the performance with output countrate up to 490 kcps will be reported.
Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2011 IEEE; 10/2011
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H Shi,
M Bazzi,
G Beer,
L Bombelli,
A M Bragadireanu,
E M Cargnelli,
G Corradi,
C Curceanu (Petrascu,
A d'Ufflzi,
C Fiorini, [......],
A Romero Vidal,
A Scordo,
D L Sirghi,
F Sirghi,
H Tatsuno,
A Tudorache,
V Tudorache,
O Vazquez Doce,
E Widmann,
J Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The SIDDHARTA (SIlicon Drift Detector for Hadronic Atom Research with Timing Application) collaboration performed X-ray spectroscopy measurement of kaonic atoms at the DAΦNE e+e−collider. Low energy negative kaons from DAΦNE -factory were stopped in gaseous targets to produce kaonic atoms. We employed specially designed Silicon Drift Detectors(SDDs) to detect the kaonic X-rays. Based on the energy of kaonic- 4He 3d → 2p transition, we determined a new value of the 2p level strong-interaction shift of kaonic- 4He: 0 ± 6 (stat.)± 2 (syst.) eV[1]. Together with the result of recent E570 experiment[2] at the KEK-PS, a small shift (if any) of kaonic- 4He 2p level has become well established.
Journal of Physics Conference Series 09/2011; 312(2):022021.
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[show abstract]
[hide abstract]
ABSTRACT: This work is focussed on the nonlinear dynamic response of electrostatically actuated micro-resonators. A single span beam axially constrained at both end, possibly with elastic constraints, is considered as representative of different common layout of micro-resonators. An analytical model, based on the Hamilton's principle, accounting for mechanical and electrical nonlinearities is derived. The analytical prediction is compared with experimental measurements obtained on a L-shaped micro-resonator.
Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE), 2011 12th International Conference on; 05/2011
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M. Bazzi,
G Beer,
L. Bombelli,
A. M. Bragadireanu,
M. Cargnelli,
G. Corradi,
C. Curceanu,
A. d'Uffizi,
C. Fiorini,
T. Frizzi, [......],
A. Scordo,
H. Shi,
D. L. Sirghi,
F. Sirghi,
H. Tatsuno,
A. Tudorache,
V. Tudorache,
O. Vazquez Doce,
E. Widmann,
J. Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The $\bar{K}N$ system at threshold is a sensitive testing ground for low
energy QCD, especially for the explicit chiral symmetry breaking. Therefore, we
have measured the $K$-series x rays of kaonic hydrogen atoms at the DA$\Phi$NE
electron-positron collider of Laboratori Nazionali di Frascati, and have
determined the most precise values of the strong-interaction energy-level shift
and width of the $1s$ atomic state. As x-ray detectors, we used large-area
silicon drift detectors having excellent energy and timing resolution, which
were developed especially for the SIDDHARTA experiment. The shift and width
were determined to be $\epsilon_{1s} = -283 \pm 36 \pm 6 {(syst)}$ eV and
$\Gamma_{1s} = 541 \pm 89 {(stat)} \pm 22 {(syst)}$ eV, respectively. The new
values will provide vital constraints on the theoretical description of the
low-energy $\bar{K}N$ interaction.
05/2011;
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[show abstract]
[hide abstract]
ABSTRACT: The Silicon Drift Detector (SDD) has been successfully employed as scintillation photodetector in the development of new gamma-ray detectors, with particular application in the field of medical imaging. In addition to other advantages, the SDD may offer a good insensitivity to magnetic fields, which represents an important feature for the use of this device in combination with MRI (Magnetic Resonance Imaging). In this work, we carry out a study about the behavior of a SDD when operated inside a MRI apparatus. We have evaluated the performances of a single detection unit which is the basic component for the realization of future imagers composed by arrays of several SDDs. The main effects on the charge collection in a SDD due to the presence of a constant magnetic field was simulated and experimentally tested on a prototype. Moreover, the effects of both gradient fields and radiofrequency signals on the device and related electronics were evaluated. Tests were also performed to verify that the presence of the detection system did not significantly perturb the images acquired with the MRI system. The experimental characterization was undertaken with a simplified detection system operated in simultaneous acquisition with a commercial MRI scanner operating at 7 T.
IEEE Transactions on Nuclear Science 05/2011; · 1.45 Impact Factor
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M Bazzi,
G Beer,
L Bombelli,
A M Bragadireanu,
M Cargnelli,
G Corradi,
C Curceanu Petrascu,
A d'Uffizi,
C Fiorini,
T Frizzi, [......],
H Shi,
D L Sirghi,
F Sirghi,
H Tatsuno,
A Tudorache,
V Tudorache,
O Vazquez Doce,
E Widmann,
B Wünschek,
J Zmeskal
[show abstract]
[hide abstract]
ABSTRACT: The first observation of the kaonic (3)He 3d→2p transition was made, using slow K- mesons stopped in a gaseous (3)He target. The kaonic atom X-rays were detected with large-area silicon drift detectors using the timing information of the K+K- pairs of ϕ-meson decays produced by the DAΦNE e+e- collider. The strong interaction shift of the kaonic (3)He 2p state was determined to be -2±2(stat)±4(syst) eV.
Physics Letters B 03/2011; 697(3-2):199-202. · 3.95 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: A new biaxial silicon resonant accelerometer characterized by a high sensitivity and a low cross-axis sensitivity is presented in this paper. The device allows for the simultaneous measure of acceleration acting along two different axes using two couples of resonating slender beams linked to two couples of flexible beams and to a proof mass. The conceptual scheme used for the biaxial resonant accelerometer is similar to the one applied for the uniaxial resonant accelerometer reported in. Experimental results demonstrate a differential sensitivity of 201 Hz/g around a resonance frequency of 84 kHz.
Micro Electro Mechanical Systems (MEMS), 2011 IEEE 24th International Conference on; 02/2011
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R. Peloso,
P. Busca,
C. Fiorini,
A. Abba,
A. Geraci,
A. Manenti, A. Longoni,
G. Padovini,
C. Bianchi,
G.L. Poli,
K. Erlandsson,
B.F. Hutton,
P. Lechner,
H. Soltau,
L. Struder,
A. Pedretti,
P. Van Mullekom,
L. Pallaro
[show abstract]
[hide abstract]
ABSTRACT: This work deals with the development of a new compact and high-resolution (<;1mm) Anger camera to be used in clinical and research environments where high overall spatial resolution and system compactness are required. The use of Silicon Drift Detectors (SDDs) as scintillator photodetectors, characterized by high quantum efficiency and low electronic noise, is the peculiar aspect of this camera. Two prototypes were produced during the project. The smaller one, composed by 25 SDDs with a 5×5cm<sup>2</sup> active area, has been used for a first assessment of the performances and first trials in small animal imaging. The larger one, developed following the same architecture, is composed by 100 SDDs of 1cm<sup>2</sup> active area each, in a 10×10cm<sup>2</sup> format. We report on the results of imaging measurements carried out with the prototypes and on the analysis of the achieved performances.
Nuclear Science Symposium Conference Record (NSS/MIC), 2010 IEEE; 12/2010
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[show abstract]
[hide abstract]
ABSTRACT: A new micromachined uniaxial silicon resonant accelerometer characterized by a high sensitivity and very small dimensions is presented. The device's working principle is based on the frequency variations of two resonating beams coupled to a proof mass. Under an external acceleration, the movement of the proof mass causes an axial load on the beams, generating opposite stiffness variations, which, in turn, result in a differential separation of their resonance frequencies. A high level of sensitivity is obtained, owing to an innovative and optimized geometrical design of the device that guarantees a great amplification of the axial loads. The acceleration measure is obtained, owing to a properly designed oscillating circuit. In agreement with the theoretical prediction, the experimental results show a sensitivity of 455 Hz/ ( g being the gravity acceleration) with a resonant frequency of about 58 kHz and a good linearity in the range of interest.
Journal of Microelectromechanical Systems 11/2010; · 2.10 Impact Factor
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C Fiorini,
A Gola,
R Peloso, A Longoni,
P Lechner,
H Soltau,
L Strüder,
L Ottobrini,
C Martelli,
R Lui,
L Madaschi,
S Belloli
[show abstract]
[hide abstract]
ABSTRACT: In this work, we present the results of the experimental characterization of the DRAGO (DRift detector Array-based Gamma camera for Oncology), a detection system developed for high-spatial resolution gamma-ray imaging. This camera is based on a monolithic array of 77 silicon drift detectors (SDDs), with a total active area of 6.7 cm(2), coupled to a single 5-mm-thick CsI(Tl) scintillator crystal. The use of an array of SDDs provides a high quantum efficiency for the detection of the scintillation light together with a very low electronics noise. A very compact detection module based on the use of integrated readout circuits was developed. The performances achieved in gamma-ray imaging using this camera are reported here. When imaging a 0.2 mm collimated (57)Co source (122 keV) over different points of the active area, a spatial resolution ranging from 0.25 to 0.5 mm was measured. The depth-of-interaction capability of the detector, thanks to the use of a Maximum Likelihood reconstruction algorithm, was also investigated by imaging a collimated beam tilted to an angle of 45 degrees with respect to the scintillator surface. Finally, the imager was characterized with in vivo measurements on mice, in a real preclinical environment.
The Review of scientific instruments 04/2010; 81(4):044301. · 1.52 Impact Factor
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[show abstract]
[hide abstract]
ABSTRACT: A new micro-machined uniaxial silicon resonant accelerometer characterized by a high sensitivity is presented. The geometrical setting is analytically optimized in order to improve the sensitivity and the linearity of the sensor. The high level of sensitivity is obtained at relatively low quality factors and keeping the dimensions very small, thanks to an innovative and optimized geometrical design of the device. The proposed accelerometer has been fabricated and the first experimental measurements are presented in the paper.
Micro Electro Mechanical Systems (MEMS), 2010 IEEE 23rd International Conference on; 02/2010
