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1 
Comparison of measured photon and electron beam dose distributions between 3D water phanton and profiler 2 scanning system, South AfricaMoji, Kabelo McDonald January 2013 (has links)
Thesis ( MSc ( Physics) )  University of Limpopo, 2013. / Background and Objectives: To establish whether the profiler 2 scanning system can be used
as a substitute for the 3Dwater phantom, by comparing the percentage depth doses and beam
profiles for both the photons and electron beams, and validating the results using CMS XiO
treatment planning system.
Methods: Beam data (profiles, percentage depth doses and absolute dosimetry) were acquired
for the two systems: (3Dwater phantom and profiler 2 scanning system) for beam energies
6 MV and 15 MV photon beams, and 4, 6, 8, 10, 12 and 15 MeV electron beams generated by
the Elekta Synergy linear accelerator (linac) for the field sizes of 6 × 6 cm2, 10 × 10 cm2, 14 × 14
cm2, 20 × 20 cm2, and 25 × 25 cm2 at depths of 0.5 cm, 1.0 cm, 2.0 cm, and 5.0 cm respectively.
These measurements were acquired using ionization chambers in water and diode detectors in
Perspex. The acquired data was sent to CMS XiO treatment planning system for validation.
Results: In general, the dose distributions for both systems compared very well with
uncertainties within recommended limits. The largest maximum difference in symmetry was
1.6 % for a 6 MV photon beam defined at 25 × 25 cm2 field size. The largest maximum
difference in flatness was 2.77 % for a 4 MeV electron beam defined at 10 × 10 cm2 applicator
size. The penumbra largest maximum difference was 1.708 cm for 8 MeV electron beam defined
at 25 × 25 cm2 applicator size, which was outside the recommended limit of 1.2 cm. The largest
maximum difference in field size was 2.388 cm for a 6 MeV electron beam defined at 20 × 20
cm2 applicator size, which was outside the recommended limit of 0.4 cm.
The largest maximum difference in percentage depth dose at 10 cm depth was 1.69 % for the
6 MV photon beam. The absolute dose output measurements showed a very good agreement
between the two systems to a maximum percentage difference and highest standard deviation of
0.99 % and 0.69 % respectively for the 6 MV photon beam. Validation measurements showed
an agreement to less than 1 % and 2 mm for percentage depth doses and beam profiles
respectively.
Conclusion and recommendation: From the results obtained, it is evident that the profiler 2
scanning system can be used as a substitute for the 3Dwater phantom beam data acquisitions
during linear accelerator commissioning. The future work based on this study could be to study
the limitations involved with the profiler 2 scanning system when used during measurements for
commissioning of a linear accelerator. Limitations like field size (maximum field size of
20 × 30 cm2 at SSD = 100 cm), number of Perspex slabs to be used on top of the profiler 2
scanning system and diagonal profile measurements.

2 
Measuring the depth of interaction of pet annihilation photons in scintillation crystalsBartzakos, Peter January 1990 (has links)
Note:

3 
A measurement of dijet photoproduction at HERA using the ZEUS detectorSaunders, Robert Luke January 1997 (has links)
No description available.

4 
Production of [pi]mesons in nucleonnucleon collisionsBrueckner, Keith A. January 1950 (has links)
Thesis (Ph. D.)University of California, Berkeley, June 1950. / Includes bibliographical references (p. 28).

5 
Polarization effects in photon echoes and in an anisotropic laser cavity.Kohl, Ronald Harry, January 1972 (has links)
Thesis (Ph. D.)Ohio State University, 1972. / Includes bibliographical references. Available online via OhioLINK's ETD Center

6 
Design and synthesis of dendrimers for studying twophoton absorption characteristicsSims, Michael Keith. January 2007 (has links) (PDF)
Thesis (M.S.)Montana State UniversityBozeman, 2007. / Typescript. Chairperson, Graduate Committee: Charles W. Spangler. Includes bibliographical references (leaves 5455).

7 
Nanowire Quantum Dots as Sources of Single and Entangled PhotonsKhoshnegar Shahrestani, Milad January 2014 (has links)
Realization of linear quantum computation and establishing secure quantum communication among interacting parties demand for triggered quantum sources delivering genuine single and entangled photons. However, the intrinsic energy level spectrum of nanostructures made by the nature or developed under a random growth process energetically lacks the expected figures of merit to produce such quantized states of photons. Here, I present the semiempirical modeling and experimental investigation on the spin fine structure of strongly confining quantum dots embedded in IIIV nanowires. To this end, the quantum dot is numerically modeled via the Configuration Interaction method at two different levels: 1) singleparticle level, where its pure energy level structure is resolved in the presence of strain and spinorbit interaction. 2) Fewparticle level, at which the fewbody interactions appear as perturbative energy corrections and orbital correlations. I demonstrate the influence of quantum confinement on the binding energies and spin fine structure of excitons in the absence of hyperfine interaction. Importantly, the highsymmetry character of excitonic orbitals in nanowire quantum dots restore the degeneracy of opticallyactive groundstate excitons, offering an ideal spectrum for the entangled photon pair generation. To experimentally verify the idea, we design and fabricate defectfree nanowire quantum dots with ultraclean excitonic spectrum, and construct the time correlation function of emitted photons through performing a series of lowtemperature statistical quantum optics measurements. We observe a decent performance in terms of single photon generation under low excitation powers. Moreover, photon pairs emitted from the biexcitonexciton cascade of nanowire quantum dots exhibit color indistinguishability and polarization entanglement owing to the trivial fine structure splitting of the groundstate excitons. We further extend the idea by proposing the hybridized states of a nanowirebased quantum dot molecule as the potential source of higherorder entangled states. Tracing the fielddependent spectrum suggests the appearance of dominant features under the weak localization of electrons and coherent tunneling of holes. In addition to their Coulomb correlation, excitons also remain spatially correlated, opening new transition channels normally forbidden in the ground state of a single dot. The proposed structure can be exploited to create tripartite hybrid, GHZ and Wentangled states.

8 
'Etudes des états finals diphoton dans l'expérience ATLAS au LHC : mesure de section efficace différentielle, découverte d'une nouvelle résonance dans la recherche du boson de Higgs et étude de ses propriétés' / 'Study of diphoton final states with the ATLAS detector at the LHC : differential crosssection measurement, discovery of a new resonance in the search of the Standard Model Higgs and measurement of its properties'Schwoerer, Maud 27 September 2013 (has links)
Cette thèse sera centrée sur les analyses des événements diphotons dans le détecteur ATLAS. L'activité évoluera au cours du temps et couvrira différents aspects: compréhension de la réponse du détecteur, participation a la prise de données, analyse physique et recherche de signaux de physique audelà du modèle standard. / These thesis will be concentrated on the analysis of events involving two photons in the final state. The activity will evolve with time and will cover different aspects: understanding of the detector response, participation to the data taking, physics analysis and search for physics behind the Standard Model

9 
A study of the reaction gamma rho reaction direction pi(sup)+pi(sup)K(sup)+K(sup)rho in the photon energy range 2070 GeVAxon, T. J. January 1984 (has links)
No description available.

10 
Hybrid entanglement for quantum communicationNape, Isaac Mphele January 2017 (has links)
A dissertation submitted to the Faculty of Science
in partial fulfillment of the requirements for the Degree of
Master of Science
School of Physics
University of Witwatersrand
November 1, 2017 / The generation and detection of entangled photons is a topic of interest in quantum
communication. With current stateoftheart methods it is possible to manipulate
any degree of freedom (DoF) of photons, e.g, polarisation, transverse momentum,
orbital angular momentum and energy. Furthermore, it is possible to combine these
DoF to realise hybrid entanglement { entanglement between the DoF of photons. In
this dissertation we focus on hybrid entanglement between photon states of coupled
orbital angular momentum and polarisation.
We engineer hybridentanglement using geometric phase control between spatially
separated photons produced from spontaneous parametric down conversion.
We present a new type of quantum eraser that does not rely on physical path interference.
We show that in principle any other degree of freedom can be used and
demonstrate this e ectively through polarisation control.
The use of high dimensional hybrid photon states in quantum communication,
particularly in quantum cryptography, is still in its infancy. Here we tailor photon
states that are coupled in their polarisation and spatial DoF (orbital angular momentum)
to realise high dimensional encoding alphabets. We show how photons entangled
in their internal DoF can be generated and deterministically detected. We exploit
them in a demonstration of a high dimensional quantum key distribution protocol
and show that our scheme generates secure keys at high rates. / MT 2018

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