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To improve the irradiation accuracy in hadron therapy, a lot of studies are in the evaluation uncluding how to integrate MRI and PET at the treatment of cancer patients. These two future techniques ...will offer simultaneously the monitoring of the beam during the irradiation. In this study and for the first time, we calculated the dose distribution in a head volume for several carbon ion energies and at different values of the magnetic field
B
using fluka MC code. Afterwards, either longitudinal or radial dose deflection was simulated with and without
B
. Basically, the
Z
axis is entered by the beam and the radial deflections mean the ones corresponded to the X axis which has the same direction of
B
. The maximum longitudinal deviation of bragg pick depth was 0.672 mm at 200 MeV and the maximum radial deflection was almost 4.23 cm at 100 MeV. Both of them are in the presence of
B
= 1.5 T. Our results are in a good agreement with previous experimental results (a maximum relative error founded of 2.08%). The results of this study will offer the monitoring of the dose deposition with good accuracy in the presence of a magnetic field in carbon ion therapy.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The energy spectrum of neutrino-induced upward-going muons in MACRO has been analysed in terms of relativity principles violating effects, keeping standard mass-induced atmospheric neutrino ...oscillations as the dominant source of νμ→ντ transitions. The data disfavor these exotic possibilities even at a subdominant level, and stringent 90% C.L. limits are placed on the Lorentz invariance violation parameter |Δv|<6×10−24 at sin2θv=0 and |Δv|<2.5–5×10−26 at sin2θv=±1. These limits can also be re-interpreted as upper bounds on the parameters describing violation of the equivalence principle.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Due to the shortage of data regarding range and water equivalent ratio (WER), in this work, firstly, depth-dose profiles and range were evaluated in liquid water, Polyethylene (PE), Aluminium, Bone, ...Polymethyl methacrylate (PMMA), and Lead for carbon ion energies ranging 100–300 MeV/n using Fluka Mc code. Afterwards, persuing the repeated use of the above mentioned materials in dosimetric studies in the domain of hadrontherapy, we came up to calculate the water equivalent ratio of only three dosimetric materials (polyethylene (PE), polymethyl methacrylate (PMMA) and lead). Then, we made the remark that the closest and farthest WER values are 1.0016 and 5.7939 respectively, they were obtained for the PE and the lead. The calculated WER values were compared with the values from MCNPX code, and those from the previous analytical methods (NM, BK, BB, EBB). Good agreement was obtained between the results of the MC codes and the previous analytical methods. The largest discrepancy between the two MC codes was 4.2% for PE at 100 MeV/n and was about 1.52% between Fluka and the analytical method (BB) for Lead at 270.83 MeV/n. Among the materials explored, PE stayed the nearest to water with an average WER of 1.0038 for carbon ion energy ranging 100 to 300 MeV/n.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Using a sample of 38.5 million underground muons collected by the MACRO detector we have performed an all-sky search for pointlike sourcesproducing excesses of muons above the expected background. ...The d.c. muon flux upper limit at the Earth coming from selected sources is of the order of 10^sup 13^ cm^sup -2^ s^sup -1^ or less. Futhermore we discuss searches for possible modulated and variable sources of muons using differenttechniques.PUBLICATION ABSTRACT
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Six stacks of CR39 (C
12H
18O
7)
n
, a Registered Trade Mark of PPG Industries, Inc. nuclear track detectors with different targets were exposed to a lead ion beam of 158
A GeV at the CERN-SPS, at ...normal incidence, in order to study the fragmentation properties of ultra-relativistic lead nuclei. Measurements of the total, break-up and pick-up charge-changing cross sections of 158
A GeV Pb ions have been made for the first time.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This research aims to achieve the desired objectives to install the devices of the prompt gamma activation analysis technique soon. For this, we participated in the realization of models and ...simulations using the Monte Carlo method to know the behavior and the neutron distribution in the collimator, the sapphire, the shutter (off state), and in the shielding. So we calculated the neutron doses in 10 different positions for the purpose to increase the confidence interval of all radiation leaks.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We present the final results of the search for stellar gravitational collapses obtained by the MACRO experiment. The detector was active for a stellar collapse search for more than 11 years and it ...was sensitive to collapses occurring all over in our galaxy for 8.6 years. A real time system for a prompt recognition of neutrino bursts was developed and was operating on-line for almost the whole life of the experiment. No signal compatible with a neutrino burst from a galactic supernova was observed.
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DOBA, FZAB, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We present the result of a search for correlations in the arrival times of high energy muons collected from 1995 till 2000 with the streamer tube system of the complete MACRO detector at the ...underground Gran Sasso Lab. Large samples of single muons (8.6 million), double muons (0.46 million) and multiple muons with multiplicities from 3 to 6 (0.08 million) were selected. These samples were used to search for time correlations of cosmic ray particles coming from the whole upper hemisphere or from selected space cones. The results of our analyses confirm with high statistics a random arrival time distribution of high energy cosmic rays.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The final analysis of atmospheric neutrino events collected with the MACRO detector is presented. Three different classes of events, generated by neutrinos in different energy ranges, are studied ...looking at rates, angular distributions and estimated energies. The results are consistent for all the subsamples and indicate a flux deficit that depends on energy and path-length of neutrinos. The no-oscillation hypothesis is excluded at \(\sim 5\sigma\), while the hypothesis of \(\nu_\mu \to \nu_\tau\) oscillation gives a satisfactory description of all data. The parameters with highest probability in a two flavor scenario are \(\sin^2 2\theta_m = 1\) and \(\Delta m^2 = 0.0023 \textrm{eV}^2\). This result is independent of the absolute normalization of the atmospheric neutrino fluxes. The data can also be used to put experimental constrain on this normalization.
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DOBA, FZAB, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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