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Published: 11 March 2023

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1

Consiglio, Lucia <1974&gt. "Algorithms for the analysis of neutrino interactions in the opera-like emulsion cloud chambers." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/331/1/PhDthesis.pdf.

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2

Consiglio, Lucia <1974&gt. "Algorithms for the analysis of neutrino interactions in the opera-like emulsion cloud chambers." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/331/.

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3

di, Ferdinando Donato <1969&gt. "Experimental study of neutrino interactions in the opera-like emulsion cloud chambers." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/332/1/PhDthesis.pdf.

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4

di, Ferdinando Donato <1969&gt. "Experimental study of neutrino interactions in the opera-like emulsion cloud chambers." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/332/.

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5

Giachini, Lisa <1978&gt. "Structure and dynamics of metal sites in proteins: X-ray Absorption Spectroscopy investigations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/334/1/tesi_giachini.pdf.

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6

Giachini, Lisa <1978&gt. "Structure and dynamics of metal sites in proteins: X-ray Absorption Spectroscopy investigations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/334/.

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7

Margaroli, Fabrizio <1976&gt. "Measurement of the top quark mass in the all-hadronic channel at proton antiproton collisions at √s = 1.96TeV with CDF II." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/348/1/tesi.pdf.

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8

Margaroli, Fabrizio <1976&gt. "Measurement of the top quark mass in the all-hadronic channel at proton antiproton collisions at √s = 1.96TeV with CDF II." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/348/.

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9

Manzoor, Shahid <1959&gt. "Improvements and calibrations of nuclear track detectors for rare particle searches and fragmentation studies." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/617/1/Manzoor_tesi.pdf.

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10

Manzoor, Shahid <1959&gt. "Improvements and calibrations of nuclear track detectors for rare particle searches and fragmentation studies." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/617/.

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11

Medinaceli, Villegas Eduardo <1976&gt. "Astroparticle physics with nuclear track detectors." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/850/1/Tesi_Medinaceli_Eduardo.pdf.

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This thesis is mainly about the search for exotic heavy particles -Intermediate Mass Magnetic Monopoles, Nuclearites and Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m, Bolivia), establishing upper limits (90% CL) in the absence of candidates, which are among the best if not the only one for all three kind of particles. A preliminary study of the background induced by cosmic neutron in CR39 at the SLIM site, using Monte Carlo simulations. The measurement of the elemental abundance of the primary cosmic ray with the CAKE experiment on board of a stratospherical balloon; the charge distribution obtained spans in the range 5≤Z≤31. Both experiments were based on the use of plastic Nuclear Track Detectors, which records the passage of ionizing particles; by using some chemical reagents such passage can be make visible at optical microscopes.
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12

Medinaceli, Villegas Eduardo <1976&gt. "Astroparticle physics with nuclear track detectors." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/850/.

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This thesis is mainly about the search for exotic heavy particles -Intermediate Mass Magnetic Monopoles, Nuclearites and Q-balls with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5230 m, Bolivia), establishing upper limits (90% CL) in the absence of candidates, which are among the best if not the only one for all three kind of particles. A preliminary study of the background induced by cosmic neutron in CR39 at the SLIM site, using Monte Carlo simulations. The measurement of the elemental abundance of the primary cosmic ray with the CAKE experiment on board of a stratospherical balloon; the charge distribution obtained spans in the range 5≤Z≤31. Both experiments were based on the use of plastic Nuclear Track Detectors, which records the passage of ionizing particles; by using some chemical reagents such passage can be make visible at optical microscopes.
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13

Codispoti, Giuseppe <1979&gt. "Sensitivity of the Top quark mass measurement with the CMS experiment at LHC using t-tbar multijet simulated events." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/852/1/Tesi_Codispoti_Giuseppe.pdf.

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This thesis comes after a strong contribution on the realization of the CMS computing system, which can be seen as a relevant part of the experiment itself. A physics analysis completes the road from Monte Carlo production and analysis tools realization to the final physics study which is the actual goal of the experiment. The topic of physics work of this thesis is the study of tt events fully hadronic decay in the CMS experiment. A multi-jet trigger has been provided to fix a reasonable starting point, reducing the multi-jet sample to the nominal trigger rate. An offline selection has been provided to reduce the S/B ratio. The b-tag is applied to provide a further S/B improvement. The selection is applied to the background sample and to the samples generated at different top quark masses. The top quark mass candidate is reconstructed for all those samples using a kinematic fitter. The resulting distributions are used to build p.d.f.’s, interpolating them with a continuous arbitrary curve. These curves are used to perform the top mass measurement through a likelihood comparison
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14

Codispoti, Giuseppe <1979&gt. "Sensitivity of the Top quark mass measurement with the CMS experiment at LHC using t-tbar multijet simulated events." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/852/.

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This thesis comes after a strong contribution on the realization of the CMS computing system, which can be seen as a relevant part of the experiment itself. A physics analysis completes the road from Monte Carlo production and analysis tools realization to the final physics study which is the actual goal of the experiment. The topic of physics work of this thesis is the study of tt events fully hadronic decay in the CMS experiment. A multi-jet trigger has been provided to fix a reasonable starting point, reducing the multi-jet sample to the nominal trigger rate. An offline selection has been provided to reduce the S/B ratio. The b-tag is applied to provide a further S/B improvement. The selection is applied to the background sample and to the samples generated at different top quark masses. The top quark mass candidate is reconstructed for all those samples using a kinematic fitter. The resulting distributions are used to build p.d.f.’s, interpolating them with a continuous arbitrary curve. These curves are used to perform the top mass measurement through a likelihood comparison
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15

Bacchi, William <1969&gt. "Evaluation of a multi variated analysis for the selection of t-tbar multijet events in the current CMS implemented environment at LHC." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/854/1/Tesi_Bacchi_William.PDF.

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In the present study we are using multi variate analysis techniques to discriminate signal from background in the fully hadronic decay channel of ttbar events. We give a brief introduction to the role of the Top quark in the standard model and a general description of the CMS Experiment at LHC. We have used the CMS experiment computing and software infrastructure to generate and prepare the data samples used in this analysis. We tested the performance of three different classifiers applied to our data samples and used the selection obtained with the Multi Layer Perceptron classifier to give an estimation of the statistical and systematical uncertainty on the cross section measurement.
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16

Bacchi, William <1969&gt. "Evaluation of a multi variated analysis for the selection of t-tbar multijet events in the current CMS implemented environment at LHC." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/854/.

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In the present study we are using multi variate analysis techniques to discriminate signal from background in the fully hadronic decay channel of ttbar events. We give a brief introduction to the role of the Top quark in the standard model and a general description of the CMS Experiment at LHC. We have used the CMS experiment computing and software infrastructure to generate and prepare the data samples used in this analysis. We tested the performance of three different classifiers applied to our data samples and used the selection obtained with the Multi Layer Perceptron classifier to give an estimation of the statistical and systematical uncertainty on the cross section measurement.
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17

Battilana, Carlo <1980&gt. "Drift Tubes Trigger System of the CMS Experiment at LHC : Commissioning and Performances." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1723/1/tesi_battilana_carlo.pdf.

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In this thesis the performances of the CMS Drift Tubes Local Trigger System of the CMS detector are studied. CMS is one of the general purpose experiments that will operate at the Large Hadron Collider at CERN. Results from data collected during the Cosmic Run At Four Tesla (CRAFT) commissioning exercise, a globally coordinated run period where the full experiment was involved and configured to detect cosmic rays crossing the CMS cavern, are presented. These include analyses on the precision and accuracy of the trigger reconstruction mechanism and measurement of the trigger efficiency. The description of a method to perform system synchronization is also reported, together with a comparison of the outcomes of trigger electronics and its software emulator code.
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18

Battilana, Carlo <1980&gt. "Drift Tubes Trigger System of the CMS Experiment at LHC : Commissioning and Performances." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1723/.

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In this thesis the performances of the CMS Drift Tubes Local Trigger System of the CMS detector are studied. CMS is one of the general purpose experiments that will operate at the Large Hadron Collider at CERN. Results from data collected during the Cosmic Run At Four Tesla (CRAFT) commissioning exercise, a globally coordinated run period where the full experiment was involved and configured to detect cosmic rays crossing the CMS cavern, are presented. These include analyses on the precision and accuracy of the trigger reconstruction mechanism and measurement of the trigger efficiency. The description of a method to perform system synchronization is also reported, together with a comparison of the outcomes of trigger electronics and its software emulator code.
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19

Costa, Filippo <1978&gt. "Hardware and software development of a multichannel readout board named CARLOSrx for the ALICE experiment." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1728/1/costa_filippo_tesi.pdf.

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ALICE, that is an experiment held at CERN using the LHC, is specialized in analyzing lead-ion collisions. ALICE will study the properties of quarkgluon plasma, a state of matter where quarks and gluons, under conditions of very high temperatures and densities, are no longer confined inside hadrons. Such a state of matter probably existed just after the Big Bang, before particles such as protons and neutrons were formed. The SDD detector, one of the ALICE subdetectors, is part of the ITS that is composed by 6 cylindrical layers with the innermost one attached to the beam pipe. The ITS tracks and identifies particles near the interaction point, it also aligns the tracks of the articles detected by more external detectors. The two ITS middle layers contain the whole 260 SDD detectors. A multichannel readout board, called CARLOSrx, receives at the same time the data coming from 12 SDD detectors. In total there are 24 CARLOSrx boards needed to read data coming from all the SDD modules (detector plus front end electronics). CARLOSrx packs data coming from the front end electronics through optical link connections, it stores them in a large data FIFO and then it sends them to the DAQ system. Each CARLOSrx is composed by two boards. One is called CARLOSrx data, that reads data coming from the SDD detectors and configures the FEE; the other one is called CARLOSrx clock, that sends the clock signal to all the FEE. This thesis contains a description of the hardware design and firmware features of both CARLOSrx data and CARLOSrx clock boards, which deal with all the SDD readout chain. A description of the software tools necessary to test and configure the front end electronics will be presented at the end of the thesis.
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20

Costa, Filippo <1978&gt. "Hardware and software development of a multichannel readout board named CARLOSrx for the ALICE experiment." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1728/.

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ALICE, that is an experiment held at CERN using the LHC, is specialized in analyzing lead-ion collisions. ALICE will study the properties of quarkgluon plasma, a state of matter where quarks and gluons, under conditions of very high temperatures and densities, are no longer confined inside hadrons. Such a state of matter probably existed just after the Big Bang, before particles such as protons and neutrons were formed. The SDD detector, one of the ALICE subdetectors, is part of the ITS that is composed by 6 cylindrical layers with the innermost one attached to the beam pipe. The ITS tracks and identifies particles near the interaction point, it also aligns the tracks of the articles detected by more external detectors. The two ITS middle layers contain the whole 260 SDD detectors. A multichannel readout board, called CARLOSrx, receives at the same time the data coming from 12 SDD detectors. In total there are 24 CARLOSrx boards needed to read data coming from all the SDD modules (detector plus front end electronics). CARLOSrx packs data coming from the front end electronics through optical link connections, it stores them in a large data FIFO and then it sends them to the DAQ system. Each CARLOSrx is composed by two boards. One is called CARLOSrx data, that reads data coming from the SDD detectors and configures the FEE; the other one is called CARLOSrx clock, that sends the clock signal to all the FEE. This thesis contains a description of the hardware design and firmware features of both CARLOSrx data and CARLOSrx clock boards, which deal with all the SDD readout chain. A description of the software tools necessary to test and configure the front end electronics will be presented at the end of the thesis.
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21

Giorgi, Filippo Maria <1981&gt. "Applications of High Speed Configurable Logic Devices in Modern Particle Physics Experiments." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1731/1/filippomaria_giorgi_tesi.pdf.

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Several activities were conducted during my PhD activity. For the NEMO experiment a collaboration between the INFN/University groups of Catania and Bologna led to the development and production of a mixed signal acquisition board for the Nemo Km3 telescope. The research concerned the feasibility study for a different acquisition technique quite far from that adopted in the NEMO Phase 1 telescope. The DAQ board that we realized exploits the LIRA06 front-end chip for the analog acquisition of anodic an dynodic sources of a PMT (Photo-Multiplier Tube). The low-power analog acquisition allows to sample contemporaneously multiple channels of the PMT at different gain factors in order to increase the signal response linearity over a wider dynamic range. Also the auto triggering and self-event-classification features help to improve the acquisition performance and the knowledge on the neutrino event. A fully functional interface towards the first level data concentrator, the Floor Control Module, has been integrated as well on the board, and a specific firmware has been realized to comply with the present communication protocols. This stage of the project foresees the use of an FPGA, a high speed configurable device, to provide the board with a flexible digital logic control core. After the validation of the whole front-end architecture this feature would be probably integrated in a common mixed-signal ASIC (Application Specific Integrated Circuit). The volatile nature of the configuration memory of the FPGA implied the integration of a flash ISP (In System Programming) memory and a smart architecture for a safe remote reconfiguration of it. All the integrated features of the board have been tested. At the Catania laboratory the behavior of the LIRA chip has been investigated in the digital environment of the DAQ board and we succeeded in driving the acquisition with the FPGA. The PMT pulses generated with an arbitrary waveform generator were correctly triggered and acquired by the analog chip, and successively they were digitized by the on board ADC under the supervision of the FPGA. For the communication towards the data concentrator a test bench has been realized in Bologna where, thanks to a lending of the Roma University and INFN, a full readout chain equivalent to that present in the NEMO phase-1 was installed. These tests showed a good behavior of the digital electronic that was able to receive and to execute command imparted by the PC console and to answer back with a reply. The remotely configurable logic behaved well too and demonstrated, at least in principle, the validity of this technique. A new prototype board is now under development at the Catania laboratory as an evolution of the one described above. This board is going to be deployed within the NEMO Phase-2 tower in one of its floors dedicated to new front-end proposals. This board will integrate a new analog acquisition chip called SAS (Smart Auto-triggering Sampler) introducing thus a new analog front-end but inheriting most of the digital logic present in the current DAQ board discussed in this thesis. For what concern the activity on high-resolution vertex detectors, I worked within the SLIM5 collaboration for the characterization of a MAPS (Monolithic Active Pixel Sensor) device called APSEL-4D. The mentioned chip is a matrix of 4096 active pixel sensors with deep N-well implantations meant for charge collection and to shield the analog electronics from digital noise. The chip integrates the full-custom sensors matrix and the sparsifification/readout logic realized with standard-cells in STM CMOS technology 130 nm. For the chip characterization a test-beam has been set up on the 12 GeV PS (Proton Synchrotron) line facility at CERN of Geneva (CH). The collaboration prepared a silicon strip telescope and a DAQ system (hardware and software) for data acquisition and control of the telescope that allowed to store about 90 million events in 7 equivalent days of live-time of the beam. My activities concerned basically the realization of a firmware interface towards and from the MAPS chip in order to integrate it on the general DAQ system. Thereafter I worked on the DAQ software to implement on it a proper Slow Control interface of the APSEL4D. Several APSEL4D chips with different thinning have been tested during the test beam. Those with 100 and 300 um presented an overall efficiency of about 90% imparting a threshold of 450 electrons. The test-beam allowed to estimate also the resolution of the pixel sensor providing good results consistent with the pitch/sqrt(12) formula. The MAPS intrinsic resolution has been extracted from the width of the residual plot taking into account the multiple scattering effect.
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22

Giorgi, Filippo Maria <1981&gt. "Applications of High Speed Configurable Logic Devices in Modern Particle Physics Experiments." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1731/.

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Abstract:
Several activities were conducted during my PhD activity. For the NEMO experiment a collaboration between the INFN/University groups of Catania and Bologna led to the development and production of a mixed signal acquisition board for the Nemo Km3 telescope. The research concerned the feasibility study for a different acquisition technique quite far from that adopted in the NEMO Phase 1 telescope. The DAQ board that we realized exploits the LIRA06 front-end chip for the analog acquisition of anodic an dynodic sources of a PMT (Photo-Multiplier Tube). The low-power analog acquisition allows to sample contemporaneously multiple channels of the PMT at different gain factors in order to increase the signal response linearity over a wider dynamic range. Also the auto triggering and self-event-classification features help to improve the acquisition performance and the knowledge on the neutrino event. A fully functional interface towards the first level data concentrator, the Floor Control Module, has been integrated as well on the board, and a specific firmware has been realized to comply with the present communication protocols. This stage of the project foresees the use of an FPGA, a high speed configurable device, to provide the board with a flexible digital logic control core. After the validation of the whole front-end architecture this feature would be probably integrated in a common mixed-signal ASIC (Application Specific Integrated Circuit). The volatile nature of the configuration memory of the FPGA implied the integration of a flash ISP (In System Programming) memory and a smart architecture for a safe remote reconfiguration of it. All the integrated features of the board have been tested. At the Catania laboratory the behavior of the LIRA chip has been investigated in the digital environment of the DAQ board and we succeeded in driving the acquisition with the FPGA. The PMT pulses generated with an arbitrary waveform generator were correctly triggered and acquired by the analog chip, and successively they were digitized by the on board ADC under the supervision of the FPGA. For the communication towards the data concentrator a test bench has been realized in Bologna where, thanks to a lending of the Roma University and INFN, a full readout chain equivalent to that present in the NEMO phase-1 was installed. These tests showed a good behavior of the digital electronic that was able to receive and to execute command imparted by the PC console and to answer back with a reply. The remotely configurable logic behaved well too and demonstrated, at least in principle, the validity of this technique. A new prototype board is now under development at the Catania laboratory as an evolution of the one described above. This board is going to be deployed within the NEMO Phase-2 tower in one of its floors dedicated to new front-end proposals. This board will integrate a new analog acquisition chip called SAS (Smart Auto-triggering Sampler) introducing thus a new analog front-end but inheriting most of the digital logic present in the current DAQ board discussed in this thesis. For what concern the activity on high-resolution vertex detectors, I worked within the SLIM5 collaboration for the characterization of a MAPS (Monolithic Active Pixel Sensor) device called APSEL-4D. The mentioned chip is a matrix of 4096 active pixel sensors with deep N-well implantations meant for charge collection and to shield the analog electronics from digital noise. The chip integrates the full-custom sensors matrix and the sparsifification/readout logic realized with standard-cells in STM CMOS technology 130 nm. For the chip characterization a test-beam has been set up on the 12 GeV PS (Proton Synchrotron) line facility at CERN of Geneva (CH). The collaboration prepared a silicon strip telescope and a DAQ system (hardware and software) for data acquisition and control of the telescope that allowed to store about 90 million events in 7 equivalent days of live-time of the beam. My activities concerned basically the realization of a firmware interface towards and from the MAPS chip in order to integrate it on the general DAQ system. Thereafter I worked on the DAQ software to implement on it a proper Slow Control interface of the APSEL4D. Several APSEL4D chips with different thinning have been tested during the test beam. Those with 100 and 300 um presented an overall efficiency of about 90% imparting a threshold of 450 electrons. The test-beam allowed to estimate also the resolution of the pixel sensor providing good results consistent with the pitch/sqrt(12) formula. The MAPS intrinsic resolution has been extracted from the width of the residual plot taking into account the multiple scattering effect.
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23

Pozzato, Michele <1980&gt. "Reconstruction of CNGS neutrino events in the emulsions of the OPERA experiment." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1755/1/PhD_Theses_Pozzato.pdf.

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The OPERA experiment aims at the direct observation of ν_mu -> ν_tau oscillations in the CNGS (CERN Neutrinos to Gran Sasso) neutrino beam produced at CERN; since the ν_e contamination in the CNGS beam is low, OPERA will also be able to study the sub-dominant oscillation channel ν_mu -> ν_e. OPERA is a large scale hybrid apparatus divided in two supermodules, each equipped with electronic detectors, an iron spectrometer and a highly segmented ~0.7 kton target section made of Emulsion Cloud Chamber (ECC) units. During my research work in the Bologna Lab. I have taken part to the set-up of the automatic scanning microscopes studying and tuning the scanning system performances and efficiencies with emulsions exposed to a test beam at CERN in 2007. Once the triggered bricks were distributed to the collaboration laboratories, my work was centered on the procedure used for the localization and the reconstruction of neutrino events.
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24

Pozzato, Michele <1980&gt. "Reconstruction of CNGS neutrino events in the emulsions of the OPERA experiment." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1755/.

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The OPERA experiment aims at the direct observation of ν_mu -> ν_tau oscillations in the CNGS (CERN Neutrinos to Gran Sasso) neutrino beam produced at CERN; since the ν_e contamination in the CNGS beam is low, OPERA will also be able to study the sub-dominant oscillation channel ν_mu -> ν_e. OPERA is a large scale hybrid apparatus divided in two supermodules, each equipped with electronic detectors, an iron spectrometer and a highly segmented ~0.7 kton target section made of Emulsion Cloud Chamber (ECC) units. During my research work in the Bologna Lab. I have taken part to the set-up of the automatic scanning microscopes studying and tuning the scanning system performances and efficiencies with emulsions exposed to a test beam at CERN in 2007. Once the triggered bricks were distributed to the collaboration laboratories, my work was centered on the procedure used for the localization and the reconstruction of neutrino events.
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25

Caforio, Davide <1970&gt. "Methods for the determination of luminosity in ATLAS with LUCID." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1912/1/Caforio_Davide_tesi.pdf.

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26

Caforio, Davide <1970&gt. "Methods for the determination of luminosity in ATLAS with LUCID." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1912/.

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27

Antonucci, Federica <1976&gt. "Search for gravitational waves from known pulsar." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/2061/1/FedericaAntonucciTesiDott.FISICA.pdf.

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28

Antonucci, Federica <1976&gt. "Search for gravitational waves from known pulsar." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/2061/.

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29

Ubaldi, Filippo <1977&gt. "Simulations and interpretation of holographic TEM images of biased and unbiased electronic devices." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/2195/1/UBALDI_FILIPPO_TESI.PDF.

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30

Ubaldi, Filippo <1977&gt. "Simulations and interpretation of holographic TEM images of biased and unbiased electronic devices." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/2195/.

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31

Carminati, Giada <1979&gt. "Study of diffuse flux of high energy neutrinos through showers with the ANTARES neutrino telescope." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3034/1/carminati_giada_tesi.pdf.

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32

Carminati, Giada <1979&gt. "Study of diffuse flux of high energy neutrinos through showers with the ANTARES neutrino telescope." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3034/.

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33

Biagi, Simone <1981&gt. "Search for a Diffuse Flux of Astrophysical Muon Neutrinos in the ANTARES Telescope." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3035/1/biagi_simone_tesi.pdf.

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34

Biagi, Simone <1981&gt. "Search for a Diffuse Flux of Astrophysical Muon Neutrinos in the ANTARES Telescope." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3035/.

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35

Tenti, Matteo <1982&gt. "Electron identification and reconstruction with the OPERA ECC bricks and search for muon neutrino to electron neutrino oscillations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4294/1/TESI.pdf.

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The procedure for event location in OPERA ECC has been optimazed for penetrating particles while is less efficient for electrons. For this reason new procedure has been defined in order to recover event with an electromagnetic shower in its final state not located with the standard one. The new procedure include the standard procedure during which several electromagnetic shower hint has been defined by means of the available data. In case the event is not located, the presence of an electromagnetic shower hint trigger a dedicated procedure. The old and new location procedure has been then simulated in order to obtain the standard location efficiency and the possible gain due to the new one for the events with electromagnetic shower. Finally a Data-MC comparison has been performed for the 2008 and 2009 runs for what concern the NC in order to validate the Monte Carlo. Then the expected electron neutrino interactions for the 2008 and 2009 runs has been evaluated and compared with the available data.
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36

Tenti, Matteo <1982&gt. "Electron identification and reconstruction with the OPERA ECC bricks and search for muon neutrino to electron neutrino oscillations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4294/.

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Abstract:
The procedure for event location in OPERA ECC has been optimazed for penetrating particles while is less efficient for electrons. For this reason new procedure has been defined in order to recover event with an electromagnetic shower in its final state not located with the standard one. The new procedure include the standard procedure during which several electromagnetic shower hint has been defined by means of the available data. In case the event is not located, the presence of an electromagnetic shower hint trigger a dedicated procedure. The old and new location procedure has been then simulated in order to obtain the standard location efficiency and the possible gain due to the new one for the events with electromagnetic shower. Finally a Data-MC comparison has been performed for the 2008 and 2009 runs for what concern the NC in order to validate the Monte Carlo. Then the expected electron neutrino interactions for the 2008 and 2009 runs has been evaluated and compared with the available data.
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37

Meneghelli, Marco <1985&gt. "Evidence for a new boson in the search for the Standard Model Higgs particle decaying to four leptons at CMS." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5174/1/Meneghelli_Marco_tesi.pdf.

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One of the main targets of the CMS experiment is to search for the Standard Model Higgs boson. The 4-lepton channel (from the Higgs decay h->ZZ->4l, l = e,mu) is one of the most promising. The analysis is based on the identification of two opposite-sign, same-flavor lepton pairs: leptons are required to be isolated and to come from the same primary vertex. The Higgs would be statistically revealed by the presence of a resonance peak in the 4-lepton invariant mass distribution. The 4-lepton analysis at CMS is presented, spanning on its most important aspects: lepton identification, variables of isolation, impact parameter, kinematics, event selection, background control and statistical analysis of results. The search leads to an evidence for a signal presence with a statistical significance of more than four standard deviations. The excess of data, with respect to the background-only predictions, indicates the presence of a new boson, with a mass of about 126 GeV/c2 , decaying to two Z bosons, whose characteristics are compatible with the SM Higgs ones.
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38

Meneghelli, Marco <1985&gt. "Evidence for a new boson in the search for the Standard Model Higgs particle decaying to four leptons at CMS." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5174/.

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Abstract:
One of the main targets of the CMS experiment is to search for the Standard Model Higgs boson. The 4-lepton channel (from the Higgs decay h->ZZ->4l, l = e,mu) is one of the most promising. The analysis is based on the identification of two opposite-sign, same-flavor lepton pairs: leptons are required to be isolated and to come from the same primary vertex. The Higgs would be statistically revealed by the presence of a resonance peak in the 4-lepton invariant mass distribution. The 4-lepton analysis at CMS is presented, spanning on its most important aspects: lepton identification, variables of isolation, impact parameter, kinematics, event selection, background control and statistical analysis of results. The search leads to an evidence for a signal presence with a statistical significance of more than four standard deviations. The excess of data, with respect to the background-only predictions, indicates the presence of a new boson, with a mass of about 126 GeV/c2 , decaying to two Z bosons, whose characteristics are compatible with the SM Higgs ones.
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39

Chiodini, Stefano <1985&gt. "In-situ and real time scanning probe microscopy of organic ultra thin films." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6772/1/Chiodini_Stefano_tesi.pdf.

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In recent decades, Organic Thin Film Transistors (OTFTs) have attracted lots of interest due to their low cost, large area and flexible properties which have brought them to be considered the building blocks of the future organic electronics. Experimentally, devices based on the same organic material deposited in different ways, i.e. by varying the deposition rate of the molecules, show different electrical performance. As predicted theoretically, this is due to the speed and rate by which charge carriers can be transported by hopping in organic thin films, transport that depends on the molecular arrangement of the molecules. This strongly suggests a correlation between the morphology of the organic semiconductor and the performance of the OTFT and hence motivated us to carry out an in-situ real time SPM study of organic semiconductor growth as an almost unprecedent experiment with the aim to fully describe the morphological evolution of the ultra-thin film and find the relevant morphological parameters affecting the OTFT electrical response. For the case of 6T on silicon oxide, we have shown that the growth mechanism is 2D+3D, with a roughening transition at the third layer and a rapid roughening. Relevant morphological parameters have been extracted by the AFM images. We also developed an original mathematical model to estimate theoretically and more accurately than before, the capacitance of an EFM tip in front of a metallic substrate. Finally, we obtained Ultra High Vacuum (UHV) AFM images of 6T at lying molecules layer both on silicon oxide and on top of 6T islands. Moreover, we performed ex-situ AFM imaging on a bilayer film composed of pentacene (a p-type semiconductor) and C60 (an n-type semiconductor).
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40

Chiodini, Stefano <1985&gt. "In-situ and real time scanning probe microscopy of organic ultra thin films." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6772/.

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Abstract:
In recent decades, Organic Thin Film Transistors (OTFTs) have attracted lots of interest due to their low cost, large area and flexible properties which have brought them to be considered the building blocks of the future organic electronics. Experimentally, devices based on the same organic material deposited in different ways, i.e. by varying the deposition rate of the molecules, show different electrical performance. As predicted theoretically, this is due to the speed and rate by which charge carriers can be transported by hopping in organic thin films, transport that depends on the molecular arrangement of the molecules. This strongly suggests a correlation between the morphology of the organic semiconductor and the performance of the OTFT and hence motivated us to carry out an in-situ real time SPM study of organic semiconductor growth as an almost unprecedent experiment with the aim to fully describe the morphological evolution of the ultra-thin film and find the relevant morphological parameters affecting the OTFT electrical response. For the case of 6T on silicon oxide, we have shown that the growth mechanism is 2D+3D, with a roughening transition at the third layer and a rapid roughening. Relevant morphological parameters have been extracted by the AFM images. We also developed an original mathematical model to estimate theoretically and more accurately than before, the capacitance of an EFM tip in front of a metallic substrate. Finally, we obtained Ultra High Vacuum (UHV) AFM images of 6T at lying molecules layer both on silicon oxide and on top of 6T islands. Moreover, we performed ex-situ AFM imaging on a bilayer film composed of pentacene (a p-type semiconductor) and C60 (an n-type semiconductor).
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41

Mingrone, Federica <1987&gt. "Radiative neutron capture cross section on 238U at the n_TOF CERN facility: a high precision measurement." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6775/1/mingrone_federica_tesi.pdf.

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The aim of this work is to provide a precise and accurate measurement of the 238U(n,gamma) reaction cross-section. This reaction is of fundamental importance for the design calculations of nuclear reactors, governing the behaviour of the reactor core. In particular, fast neutron reactors, which are experiencing a growing interest for their ability to burn radioactive waste, operate in the high energy region of the neutron spectrum. In this energy region inconsistencies between the existing measurements are present up to 15%, and the most recent evaluations disagree each other. In addition, the assessment of nuclear data uncertainty performed for innovative reactor systems shows that the uncertainty in the radiative capture cross-section of 238U should be further reduced to 1-3% in the energy region from 20 eV to 25 keV. To this purpose, addressed by the Nuclear Energy Agency as a priority nuclear data need, complementary experiments, one at the GELINA and two at the n_TOF facility, were scheduled within the ANDES project within the 7th Framework Project of the European Commission. The results of one of the 238U(n,gamma) measurement performed at the n_TOF CERN facility are presented in this work, carried out with a detection system constituted of two liquid scintillators. The very accurate cross section from this work is compared with the results obtained from the other measurement performed at the n_TOF facility, which exploit a different and complementary detection technique. The excellent agreement between the two data-sets points out that they can contribute to the reduction of the cross section uncertainty down to the required 1-3%.
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42

Mingrone, Federica <1987&gt. "Radiative neutron capture cross section on 238U at the n_TOF CERN facility: a high precision measurement." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6775/.

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Abstract:
The aim of this work is to provide a precise and accurate measurement of the 238U(n,gamma) reaction cross-section. This reaction is of fundamental importance for the design calculations of nuclear reactors, governing the behaviour of the reactor core. In particular, fast neutron reactors, which are experiencing a growing interest for their ability to burn radioactive waste, operate in the high energy region of the neutron spectrum. In this energy region inconsistencies between the existing measurements are present up to 15%, and the most recent evaluations disagree each other. In addition, the assessment of nuclear data uncertainty performed for innovative reactor systems shows that the uncertainty in the radiative capture cross-section of 238U should be further reduced to 1-3% in the energy region from 20 eV to 25 keV. To this purpose, addressed by the Nuclear Energy Agency as a priority nuclear data need, complementary experiments, one at the GELINA and two at the n_TOF facility, were scheduled within the ANDES project within the 7th Framework Project of the European Commission. The results of one of the 238U(n,gamma) measurement performed at the n_TOF CERN facility are presented in this work, carried out with a detection system constituted of two liquid scintillators. The very accurate cross section from this work is compared with the results obtained from the other measurement performed at the n_TOF facility, which exploit a different and complementary detection technique. The excellent agreement between the two data-sets points out that they can contribute to the reduction of the cross section uncertainty down to the required 1-3%.
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43

Massoli, Fabio Valerio <1987&gt. "The XENON1T experiment: Monte Carlo background estimation and sensitivity curves study." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6776/1/Massoli_FabioValerio_tesi.pdf.

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Despite the scientific achievement of the last decades in the astrophysical and cosmological fields, the majority of the Universe energy content is still unknown. A potential solution to the “missing mass problem” is the existence of dark matter in the form of WIMPs. Due to the very small cross section for WIMP-nuleon interactions, the number of expected events is very limited (about 1 ev/tonne/year), thus requiring detectors with large target mass and low background level. The aim of the XENON1T experiment, the first tonne-scale LXe based detector, is to be sensitive to WIMP-nucleon cross section as low as 10^-47 cm^2. To investigate the possibility of such a detector to reach its goal, Monte Carlo simulations are mandatory to estimate the background. To this aim, the GEANT4 toolkit has been used to implement the detector geometry and to simulate the decays from the various background sources: electromagnetic and nuclear. From the analysis of the simulations, the level of background has been found totally acceptable for the experiment purposes: about 1 background event in a 2 tonne-years exposure. Indeed, using the Maximum Gap method, the XENON1T sensitivity has been evaluated and the minimum for the WIMP-nucleon cross sections has been found at 1.87 x 10^-47 cm^2, at 90% CL, for a WIMP mass of 45 GeV/c^2. The results have been independently cross checked by using the Likelihood Ratio method that confirmed such results with an agreement within less than a factor two. Such a result is completely acceptable considering the intrinsic differences between the two statistical methods. Thus, in the PhD thesis it has been proven that the XENON1T detector will be able to reach the designed sensitivity, thus lowering the limits on the WIMP-nucleon cross section by about 2 orders of magnitude with respect to the current experiments.
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44

Massoli, Fabio Valerio <1987&gt. "The XENON1T experiment: Monte Carlo background estimation and sensitivity curves study." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/6776/.

Full text
Abstract:
Despite the scientific achievement of the last decades in the astrophysical and cosmological fields, the majority of the Universe energy content is still unknown. A potential solution to the “missing mass problem” is the existence of dark matter in the form of WIMPs. Due to the very small cross section for WIMP-nuleon interactions, the number of expected events is very limited (about 1 ev/tonne/year), thus requiring detectors with large target mass and low background level. The aim of the XENON1T experiment, the first tonne-scale LXe based detector, is to be sensitive to WIMP-nucleon cross section as low as 10^-47 cm^2. To investigate the possibility of such a detector to reach its goal, Monte Carlo simulations are mandatory to estimate the background. To this aim, the GEANT4 toolkit has been used to implement the detector geometry and to simulate the decays from the various background sources: electromagnetic and nuclear. From the analysis of the simulations, the level of background has been found totally acceptable for the experiment purposes: about 1 background event in a 2 tonne-years exposure. Indeed, using the Maximum Gap method, the XENON1T sensitivity has been evaluated and the minimum for the WIMP-nucleon cross sections has been found at 1.87 x 10^-47 cm^2, at 90% CL, for a WIMP mass of 45 GeV/c^2. The results have been independently cross checked by using the Likelihood Ratio method that confirmed such results with an agreement within less than a factor two. Such a result is completely acceptable considering the intrinsic differences between the two statistical methods. Thus, in the PhD thesis it has been proven that the XENON1T detector will be able to reach the designed sensitivity, thus lowering the limits on the WIMP-nucleon cross section by about 2 orders of magnitude with respect to the current experiments.
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45

Colocci, Manuel <1987&gt. "Misura di precisione della differenza di massa fra nuclei e anti-nuclei leggeri con l'esperimento ALICE a LHC." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7262/1/colocci_manuel_tesi.pdf.

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Con questo lavoro è stata effettuata una misura della differenza $\Delta \mu = \Delta (m / |z|)$ fra il rapporto massa su carica del deutone (d) e dell'anti-deutone (${\rm \overline{d}}$), e del nucleo di ${\rm ^{3}He}$ e di anti-${\rm ^{3}He}$ con l'esperimento ALICE ad LHC in collisioni Pb--Pb a un'energia nel centro di massa per coppia di nucleoni $\sqrt{s_{\rm NN}}=2.76~{\rm TeV}$. Le misure sono pari a ${\Delta \mu}_{\rm{d\bar{d}}}/{\mu}_{\rm{d}} = [0.9 \pm 0.5 (\rm{stat.}) \pm 1.4 (\rm{syst.})] \times 10^{-4}$ e ${\Delta \mu}_{\rm{^{3}He ^{3}\overline{He}}}/{\mu}_{\rm{^{3}He}} = [-1.2 \pm 0.9 (\rm{stat.}) \pm 1.0 (\rm{syst.})] \times 10^{-3}$. Combinando questi risultati con le misure esistenti delle masse dei (anti-)nucleoni, sono state estratte le corrispondenti differenze di energia di legame ${\Delta \varepsilon}_{\rm{d\bar{d}}}/{\varepsilon}_{\rm{d}} = -0.04 \pm 0.05(\rm{stat.}) \pm 0.12(\rm{syst.})$ e ${\Delta \varepsilon}_{\rm{^{3}He ^{3}\overline{He}}}/{\varepsilon}_{\rm{^{3}He}} = 0.24 \pm 0.16(\rm{stat.}) \pm 0.18(\rm{syst.})$. I risultati verificano, con una precisione senza precedenti, l'invarianza CPT nel settore dei nuclei leggeri.
With this work a measurement of the difference $\Delta \mu = \Delta (m / |z|)$ between the mass-over-charge ratio of deuteron (d) and anti-deuteron (${\rm \overline{d}}$), and ${\rm ^{3}He}$ and ${\rm ^{3}\overline{He}}$ nuclei, carried out with the ALICE experiment in Pb--Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}}=~2.76~\rm{TeV}$ has been performed. The measurement yields ${\Delta \mu}_{\rm{d\bar{d}}}/{\mu}_{\rm{d}} = [0.9 \pm 0.5 (\rm{stat.}) \pm 1.4 (\rm{syst.})] \times 10^{-4}$ and ${\Delta \mu}_{\rm{^{3}He ^{3}\overline{He}}}/{\mu}_{\rm{^{3}He}} = [-1.2 \pm 0.9 (\rm{stat.}) \pm 1.0 (\rm{syst.})] \times 10^{-3}$. Combining these results with existing measurements of the masses of the (anti-)nucleons, the relative binding energy differences are extracted, ${\Delta \varepsilon}_{\rm{d\bar{d}}}/{\varepsilon}_{\rm{d}} = -0.04 \pm 0.05(\rm{stat.}) \pm 0.12(\rm{syst.})$ and ${\Delta \varepsilon}_{\rm{^{3}He ^{3}\overline{He}}}/{\varepsilon}_{\rm{^{3}He}} = 0.24 \pm 0.16(\rm{stat.}) \pm 0.18(\rm{syst.})$. These results test, to an unprecedented precision, the CPT invariance in the sector of light nuclei.
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46

Colocci, Manuel <1987&gt. "Misura di precisione della differenza di massa fra nuclei e anti-nuclei leggeri con l'esperimento ALICE a LHC." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7262/.

Full text
Abstract:
Con questo lavoro è stata effettuata una misura della differenza $\Delta \mu = \Delta (m / |z|)$ fra il rapporto massa su carica del deutone (d) e dell'anti-deutone (${\rm \overline{d}}$), e del nucleo di ${\rm ^{3}He}$ e di anti-${\rm ^{3}He}$ con l'esperimento ALICE ad LHC in collisioni Pb--Pb a un'energia nel centro di massa per coppia di nucleoni $\sqrt{s_{\rm NN}}=2.76~{\rm TeV}$. Le misure sono pari a ${\Delta \mu}_{\rm{d\bar{d}}}/{\mu}_{\rm{d}} = [0.9 \pm 0.5 (\rm{stat.}) \pm 1.4 (\rm{syst.})] \times 10^{-4}$ e ${\Delta \mu}_{\rm{^{3}He ^{3}\overline{He}}}/{\mu}_{\rm{^{3}He}} = [-1.2 \pm 0.9 (\rm{stat.}) \pm 1.0 (\rm{syst.})] \times 10^{-3}$. Combinando questi risultati con le misure esistenti delle masse dei (anti-)nucleoni, sono state estratte le corrispondenti differenze di energia di legame ${\Delta \varepsilon}_{\rm{d\bar{d}}}/{\varepsilon}_{\rm{d}} = -0.04 \pm 0.05(\rm{stat.}) \pm 0.12(\rm{syst.})$ e ${\Delta \varepsilon}_{\rm{^{3}He ^{3}\overline{He}}}/{\varepsilon}_{\rm{^{3}He}} = 0.24 \pm 0.16(\rm{stat.}) \pm 0.18(\rm{syst.})$. I risultati verificano, con una precisione senza precedenti, l'invarianza CPT nel settore dei nuclei leggeri.
With this work a measurement of the difference $\Delta \mu = \Delta (m / |z|)$ between the mass-over-charge ratio of deuteron (d) and anti-deuteron (${\rm \overline{d}}$), and ${\rm ^{3}He}$ and ${\rm ^{3}\overline{He}}$ nuclei, carried out with the ALICE experiment in Pb--Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}}=~2.76~\rm{TeV}$ has been performed. The measurement yields ${\Delta \mu}_{\rm{d\bar{d}}}/{\mu}_{\rm{d}} = [0.9 \pm 0.5 (\rm{stat.}) \pm 1.4 (\rm{syst.})] \times 10^{-4}$ and ${\Delta \mu}_{\rm{^{3}He ^{3}\overline{He}}}/{\mu}_{\rm{^{3}He}} = [-1.2 \pm 0.9 (\rm{stat.}) \pm 1.0 (\rm{syst.})] \times 10^{-3}$. Combining these results with existing measurements of the masses of the (anti-)nucleons, the relative binding energy differences are extracted, ${\Delta \varepsilon}_{\rm{d\bar{d}}}/{\varepsilon}_{\rm{d}} = -0.04 \pm 0.05(\rm{stat.}) \pm 0.12(\rm{syst.})$ and ${\Delta \varepsilon}_{\rm{^{3}He ^{3}\overline{He}}}/{\varepsilon}_{\rm{^{3}He}} = 0.24 \pm 0.16(\rm{stat.}) \pm 0.18(\rm{syst.})$. These results test, to an unprecedented precision, the CPT invariance in the sector of light nuclei.
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47

Fusco, Luigi Antonio <1988&gt. "Search for a Diffuse Neutrino Emission in the Southern Sky with the Antares Telescope." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7269/1/Tesi_fusco.pdf.

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Compelling evidence of the existence of cosmic neutrinos has been reported by the IceCube collaboration. Some features of this signal could be explained by a Northern/Southern sky asymmetry of the flux. This possible asymmetry would be related to the presence of the bulk our Galaxy in the Southern sky. The ANTARES neutrino telescope, located in the Mediterranean Sea, consists of a three dimensional array of 885 10-inch photomultiplier tubes distributed along twelve vertical lines. Its effective area and its good exposure to the Southern Sky would allow to constrain an enhanced muon neutrino emission from extended sources. An excess of events from the Galactic Plane is searched for. A signal region around the inner Galactic Plane is defined; the background from atmospheric events is estimated looking at data from off-zones for which ANTARES has the same exposure as for the signal region. The ANTARES sensitivity to such a flux has been computed. The results of the analysis after unblinding will be presented.
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48

Fusco, Luigi Antonio <1988&gt. "Search for a Diffuse Neutrino Emission in the Southern Sky with the Antares Telescope." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7269/.

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Abstract:
Compelling evidence of the existence of cosmic neutrinos has been reported by the IceCube collaboration. Some features of this signal could be explained by a Northern/Southern sky asymmetry of the flux. This possible asymmetry would be related to the presence of the bulk our Galaxy in the Southern sky. The ANTARES neutrino telescope, located in the Mediterranean Sea, consists of a three dimensional array of 885 10-inch photomultiplier tubes distributed along twelve vertical lines. Its effective area and its good exposure to the Southern Sky would allow to constrain an enhanced muon neutrino emission from extended sources. An excess of events from the Galactic Plane is searched for. A signal region around the inner Galactic Plane is defined; the background from atmospheric events is estimated looking at data from off-zones for which ANTARES has the same exposure as for the signal region. The ANTARES sensitivity to such a flux has been computed. The results of the analysis after unblinding will be presented.
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49

Massa, Lorenzo <1988&gt. "Measurement of the t-tbar differential cross section at large top quark transverse momentum in sqrt(8) TeV pp collisions using the ATLAS detector at the LHC." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7272/1/Tesi_dottorato_LorenzoMassa.pdf.

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The top quark is the heaviest particle in Standard Model. When it is produced with a large Lorentz boost, its decay products tend to overlap, making the standard reconstruction techniques inefficient; large R jet substructure analysis techniques allow to increase the detection efficiency for these events. Various differential cross section measurements of boosted t-tbar from pp collisions with sqrt(s)=8 TeV are presented: with respect to the mass, to the transverse momentum and the pseudorapidity of the t-tbar system. The results here have been obtained using a sample of 20 fb^-1, recorded by ATLAS during 2012. The events are selected with a cut-based approach in the single lepton plus jets decay channel, where the lepton can be either an electron or a muon. The final background-subtracted distributions are corrected for the distortion introduced by the detector and selection effects using unfolding methods. The measurements are dominated by the systematic uncertainties, and are in agreement with the Standard Model, even if it can be seen a general tendency of the theoretical predictions to overestimate the measured cross section for increasing transverse momentum and mass of the t-tbar system.
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50

Massa, Lorenzo <1988&gt. "Measurement of the t-tbar differential cross section at large top quark transverse momentum in sqrt(8) TeV pp collisions using the ATLAS detector at the LHC." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7272/.

Full text
Abstract:
The top quark is the heaviest particle in Standard Model. When it is produced with a large Lorentz boost, its decay products tend to overlap, making the standard reconstruction techniques inefficient; large R jet substructure analysis techniques allow to increase the detection efficiency for these events. Various differential cross section measurements of boosted t-tbar from pp collisions with sqrt(s)=8 TeV are presented: with respect to the mass, to the transverse momentum and the pseudorapidity of the t-tbar system. The results here have been obtained using a sample of 20 fb^-1, recorded by ATLAS during 2012. The events are selected with a cut-based approach in the single lepton plus jets decay channel, where the lepton can be either an electron or a muon. The final background-subtracted distributions are corrected for the distortion introduced by the detector and selection effects using unfolding methods. The measurements are dominated by the systematic uncertainties, and are in agreement with the Standard Model, even if it can be seen a general tendency of the theoretical predictions to overestimate the measured cross section for increasing transverse momentum and mass of the t-tbar system.
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