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Continuous high-yield fast neutron generation with few-cycle laser pulses at 10 Hz for applications
Authors:
L. Stuhl,
P. Varmazyar,
Z. Elekes,
Z. Halász,
T. Gilinger,
M. Füle,
M. Karnok,
E. Buzás,
A. P. Kovács,
B. Nagy,
A. Mohácsi,
B. Bíró,
L. Csedreki,
A. Fenyvesi,
Zs. Fülöp,
Z. Korkulu,
I. Kuti,
J. Csontos,
P. P. Geetha,
Sz. Tóth,
G. Szabó,
K. Osvay
Abstract:
We present a laser-based neutron source that produces $1.8 \times 10^5$ neutrons/s with a conversion rate of $7.8 \times 10^5$ neutrons/J. Laser pulses of 12 fs and 23 mJ were focused onto a 430-nm-thick heavy water liquid sheet at a 10 Hz repetition rate. The resulting peak intensity of $4 \times 10^{18}$ W/cm$^2$ accelerated deuterium ions from the target rear side to a kinetic energy of 1 MeV.…
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We present a laser-based neutron source that produces $1.8 \times 10^5$ neutrons/s with a conversion rate of $7.8 \times 10^5$ neutrons/J. Laser pulses of 12 fs and 23 mJ were focused onto a 430-nm-thick heavy water liquid sheet at a 10 Hz repetition rate. The resulting peak intensity of $4 \times 10^{18}$ W/cm$^2$ accelerated deuterium ions from the target rear side to a kinetic energy of 1 MeV. This deuteron beam induced $^{2}$H(d,n)$^{3}$He fusion reactions in a deuterated polyethylene target, producing fast neutrons. The neutron yield was measured using two independent detection systems: the LILITH time-of-flight spectrometer, consisting of eight plastic scintillators covering nearly $180^\circ$, and a calibrated bubble detector spectrometer. The neutron yield per laser shot is 35 times higher than that recently achieved by lasers with comparable pulse energies, while the conversion rate is the highest ever achieved by continuously operating, sub-100 fs lasers. The generated neutrons are emitted from an area of 0.65 cm$^2$ corresponding to the deuteron beam spot on the catcher. Their angular distribution is peaked in forward and backward directions in agreement with the literature data on the angular distribution of $^{2}$H(d,n)$^{3}$He reaction. The system operated continuously for several hours per day with an unprecedented stability of 5%.
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Submitted 12 February, 2025;
originally announced February 2025.
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A Comparison of the Effects of Neutron and Gamma Radiation in Silicon Photomultipliers
Authors:
B. Biró,
G. David,
A. Fenyvesi,
J. S. Haggerty,
J. Kierstead,
E. J. Mannel,
T. Majoros,
J. Molnar,
F. Nagy,
S. Stoll,
B. Ujvari,
C. L. Woody
Abstract:
The effects of radiation damage in silicon photomultipliers (SiPMs) from gamma rays have been measured and compared with the damage produced by neutrons. Several types of MPPCs from Hamamatsu were exposed to gamma rays and neutrons at the Solid State Gamma Ray Irradiation Facility (SSGRIF) at Brookhaven National Lab and the Institute for Nuclear Research (Atomki) in Debrecen, Hungary. The gamma ra…
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The effects of radiation damage in silicon photomultipliers (SiPMs) from gamma rays have been measured and compared with the damage produced by neutrons. Several types of MPPCs from Hamamatsu were exposed to gamma rays and neutrons at the Solid State Gamma Ray Irradiation Facility (SSGRIF) at Brookhaven National Lab and the Institute for Nuclear Research (Atomki) in Debrecen, Hungary. The gamma ray exposures ranged from 1 krad to 1 Mrad and the neutron exposures ranged from 10$^8$ n/cm$^2$ to 10$^{12}$ n/cm$^2$. The main effect of gamma ray damage is an increase in the noise and leakage current in the irradiated devices, similar to what is seen from neutron damage, but the level of damage is considerably less at comparable high levels of exposure. In addition, the damage from gamma rays saturates after a few hundred krad, while the damage from neutrons shows no sign of saturation, suggestive of different damage mechanisms in the two cases. The change in optical absorption in the window material of the SiPMs due to radiation was also measured. This study was carried out in order to evaluate the use of SiPMs for particle physics applications with moderate levels of radiation exposures.
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Submitted 7 April, 2019; v1 submitted 12 September, 2018;
originally announced September 2018.
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A novel application of Fiber Bragg Grating (FBG) sensors in MPGD
Authors:
D. Abbaneo,
M. Abbas,
M. Abbrescia,
A. A. Abdelalim,
M. Abi Akl,
O. Aboamer,
D. Acosta,
A. Ahmad,
W. Ahmed,
W. Ahmed,
A. Aleksandrov,
R. Aly,
P. Altieri,
C. Asawatangtrakuldee,
P. Aspell,
Y. Assran,
I. Awan,
S. Bally,
Y. Ban,
S. Banerjee,
V. Barashko,
P. Barria,
G. Bencze,
N. Beni,
L. Benussi
, et al. (133 additional authors not shown)
Abstract:
We present a novel application of Fiber Bragg Grating (FBG) sensors in the construction and characterisation of Micro Pattern Gaseous Detector (MPGD), with particular attention to the realisation of the largest triple (Gas electron Multiplier) GEM chambers so far operated, the GE1/1 chambers of the CMS experiment at LHC. The GE1/1 CMS project consists of 144 GEM chambers of about 0.5 m2 active are…
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We present a novel application of Fiber Bragg Grating (FBG) sensors in the construction and characterisation of Micro Pattern Gaseous Detector (MPGD), with particular attention to the realisation of the largest triple (Gas electron Multiplier) GEM chambers so far operated, the GE1/1 chambers of the CMS experiment at LHC. The GE1/1 CMS project consists of 144 GEM chambers of about 0.5 m2 active area each, employing three GEM foils per chamber, to be installed in the forward region of the CMS endcap during the long shutdown of LHC in 2108-2019. The large active area of each GE1/1 chamber consists of GEM foils that are mechanically stretched in order to secure their flatness and the consequent uniform performance of the GE1/1 chamber across its whole active surface. So far FBGs have been used in high energy physics mainly as high precision positioning and re-positioning sensors and as low cost, easy to mount, low space consuming temperature sensors. FBGs are also commonly used for very precise strain measurements in material studies. In this work we present a novel use of FBGs as flatness and mechanical tensioning sensors applied to the wide GEM foils of the GE1/1 chambers. A network of FBG sensors have been used to determine the optimal mechanical tension applied and to characterise the mechanical tension that should be applied to the foils. We discuss the results of the test done on a full-sized GE1/1 final prototype, the studies done to fully characterise the GEM material, how this information was used to define a standard assembly procedure and possible future developments.
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Submitted 28 December, 2015;
originally announced December 2015.
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Fiber Bragg Grating (FBG) sensors as flatness and mechanical stretching sensors
Authors:
D. Abbaneo,
M. Abbas,
M. Abbrescia,
A. A. Abdelalim,
M. Abi Akl,
O. Aboamer,
D. Acosta,
A. Ahmad,
W. Ahmed,
W. Ahmed,
A. Aleksandrov,
R. Aly,
P. Altieri,
C. Asawatangtrakuldee,
P. Aspell,
Y. Assran,
I. Awan,
S. Bally,
Y. Ban,
S. Banerjee,
V. Barashko,
P. Barria,
G. Bencze,
N. Beni,
L. Benussi
, et al. (133 additional authors not shown)
Abstract:
A novel approach which uses Fibre Bragg Grating (FBG) sensors has been utilised to assess and monitor the flatness of Gaseous Electron Multipliers (GEM) foils. The setup layout and preliminary results are presented.
A novel approach which uses Fibre Bragg Grating (FBG) sensors has been utilised to assess and monitor the flatness of Gaseous Electron Multipliers (GEM) foils. The setup layout and preliminary results are presented.
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Submitted 28 December, 2015;
originally announced December 2015.
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Estimations and integral measurements for the spectral yield of neutrons from thick beryllium target bombarded with 16 MeV protons
Authors:
A. Fenyvesi
Abstract:
Spectral yield of p+Be neutrons emitted by thick (stopping) beryllium target bombarded by 16 MeV protons was estimated via extrapolation of literature data. The spectrum was validated via multi-foil activation method and irradiation of 2N2222 transistors. The hardness parameter (NIEL scaling factor) for displacement damage in bulk silicon was calculated and measured and kappa = 1.26 +- 0.1 was obt…
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Spectral yield of p+Be neutrons emitted by thick (stopping) beryllium target bombarded by 16 MeV protons was estimated via extrapolation of literature data. The spectrum was validated via multi-foil activation method and irradiation of 2N2222 transistors. The hardness parameter (NIEL scaling factor) for displacement damage in bulk silicon was calculated and measured and kappa = 1.26 +- 0.1 was obtained.
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Submitted 28 April, 2015;
originally announced April 2015.