Do background to neutrino oscillations in the opera experiment

Tufanlı, Serhan
The OPERA experiment is designed to search for nu-tau appearance in almost pure CERN-SPS nu-mu beam. The OPERA detector is placed in the Gran Sasso underground laboratory which is 730 km away from CERN. It is a hybrid set-up which combines a lead/emulsion target with various electronic detectors. The detector is composed of two super modules(SM) which contains about 150,000 ECC bricks. Each of the brick is obtained by stacking 56 lead plates with 57 emulsion films. Behind the each brick, an emulsion film doublet, called Changeable Sheet (CS) is attached in order to confirm tracks produced in neutrino interactions. The CS requires very low background track density in order to ensure the expected performance in the experiment. The background tracks in CS can be erased by a special treatment called as refreshing. A refreshing facility was constructed in the LNGS laboratory. The METU group has participated in the construction of the facility and the production of the CS films from the beginning. The main steps of emulsion refreshing and the test results on emulsion quality after the refreshing will be discussed. A Monte Carlo simulation is performed in order to estimate background to nu-mu to nu-tau oscillation due to D0 production and decay in the ECC brick. It is found that this background is significant for the short decay path topology of the tau lepton.


Study of electron identification in the opera detector
Bay, M. Fatih; Güler, Ali Murat; Department of Physics (2008)
The OPERA experiment is designed to perform first direct observation of $\nu_{\tau}$ appearance in an almost pure $\nu_{\mu}$ beam. The OPERA detector is a hybrid set-up which combines a lead/emulsion target with various electronic detectors. It is located in Gran Sasso Laboratory (LNGS), 730 km away from CERN where neutrino beam is produced. A good electron identification in the ECC brick would also allow OPERA to search for $\nu_{\mu}\rightarrow\nu_{e}$ oscillations. We have studied electron identificatio...
Search for dark matter produced in association with heavy-flavor quark pairs in proton-proton collisions at root s=13 TeV
Sirunyan, A. M.; et. al. (2017-12-01)
A search is presented for an excess of events with heavy-flavor quark pairs (t (t) over bar and b (b) over bar) and a large imbalance in transverse momentum in data from proton-proton collisions at a center-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 2.2 fb(-1) collected with the CMS detector at the CERN LHC. No deviations are observed with respect to standard model predictions. The results are used in the first interpretation of dark matter production in t (t) over bar and ...
Graviton induced monojet production in cms within add type led
Surat, Uğur Emrah; Serin, Meltem; Department of Physics (2010)
The discovery reach for the ADD-type Large Extra Dimension (LED) scenario in the CMS Experiment at the LHC is presented by looking at the Monojet + Missing Energy signature, which arises as a result of a single graviton emission accompanied by a quark or gluon. Using Monte Carlo generated events, two LHC run scenarios were considered and compared namely a center-of-mass energy of 14 TeV and integrated luminosity of 100 pb−1, and a center-of-mass energy of 10 TeV and integrated luminosity of 200 pb−1. Detail...
First events from the CNGS neutrino beam detected in the OPERA experiment
Acquafredda, R; et. al. (IOP Publishing, 2006-12-5)
The OPERA neutrino detector at the underground Gran Sasso Laboratory (LNGS) was designed to perform the first detection of neutrino oscillations in appearance mode, through the study of νµ → ντ oscillations. The apparatus consists of a lead/emulsion-film target complemented by electronic detectors. It is placed in the high-energy, long-baseline CERN to LNGS beam (CNGS) 730 km away from the neutrino source. In August 2006, a first run with CNGS neutrinos was successfully conducted. A first sample of ne...
Final Results of the OPERA Experiment on nu(tau )Appearance In the CNGS Neutrino Beam
Agafonova, N.; et. al. (American Physical Society (APS), 2018-05-22)
The OPERA experiment was designed to study νμ→ντ oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×1019 protons on target. Selection criteria looser than in previous analyses have produced ten ντ candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ντ properties. A multivariate approach fo...
Citation Formats
S. Tufanlı, “Do background to neutrino oscillations in the opera experiment,” M.S. - Master of Science, Middle East Technical University, 2009.