Silicon micro-channel cooling is being studied for efficient thermal management in application fields such as high power computing and 3D electronic integration. This concept has been introduced in ...2010 for the thermal management of silicon pixel detectors in high energy physics experiments. Combining the versatility of standard micro-fabrication processes with the high thermal efficiency typical of micro-fluidics, it is possible to produce effective thermal management devices that are well adapted to different detector configurations. The production of very thin cooling devices in silicon enables a minimization of material of the tracking sensors and eliminates mechanical stresses due to the mismatch of the coefficient of thermal expansion between detectors and cooling systems. The NA62 experiment at CERN will be the first high particle physics experiment that will install a micro-cooling system to perform the thermal management of the three detection planes of its Gigatracker pixel detector.
Today’s greatest challenge in accelerator-based neutrino physics is to measure the mixing angle θ13 which is known to be much smaller than the solar mixing angle θ12 and the atmospheric mixing angle ...θ23. A non-zero value of the angle θ13 is a prerequisite for observing CP violation in neutrino mixing. In this paper, we discuss a deep-sea neutrino experiment with 1.5 Mt fiducial target mass in the Gulf of Taranto with the prime objective of measuring θ13. The detector is exposed to the CERN neutrino beam to Gran Sasso in off-axis geometry. Monochromatic muon neutrinos of ≈ 800 MeV energy are the dominant beam component. Neutrinos are detected through quasi-elastic, charged-current reactions in sea water; electrons and muons are detected in a large-surface, ring-imaging Cherenkov detector. The profile of the seabed in the Gulf of Taranto allows for a moveable experiment at variable distances from CERN, starting at 1100 km. From the oscillatory pattern of the disappearance of muon neutrinos, the experiment will measure sin2θ23 and especially Δm223 with high precision. The appearance of electron neutrinos will be observed with a sensitivity to P(νμ→νe) as small as 0.0035 (90% CL) and sin2θ13 as small as 0.0019 (90% CL; for a CP phase angle δ=0° and for normal neutrino mass hierarchy).
A large spherical HPD for a novel deep-sea neutrino experiment Ball, A.E.; Braem, A.; Camilleri, L. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2005, Letnik:
553, Številka:
1
Journal Article
Recenzirano
An underwater neutrino experiment has been proposed which provides precise measurements of the neutrino mixing parameters
θ
23 and
Δ
m
23
2
and permits an increase of sensitivity for the small angle
...θ
13 by more than one order of magnitude. A Cherenkov detector of about 1.5
Mt active mass, deployed in the Gulf of Taranto, utilizes the CNGS beam in off-axis configuration which represents an essentially mono-energetic source of muon neutrinos. A unique feature of the experiment is the possibility to move the detector and therefore exploit different baselines around 1200
km where the oscillation pattern is fully developed. The conceptual detector design consists of O(30,000) large area and acceptance photosensors arranged in a matrix of ∼300×300
m
2 size. Hybrid photon detectors are considered as promising candidates as they provide clean signal characteristics and uniform collection efficiency. We discuss the design and expected performance of a large spherical HPD with 380
mm diameter, which is housed in a high-pressure glass container. A scaled prototype HPD of 208
mm diameter is currently under development using the existing CERN HPD facility.
A dedicated sample of Large Hadron Collider proton-proton collision data at centre-of-mass energy $ \sqrt{s} $ = 8 TeV is used to study inclusive single diffractive dissociation, pp → X p. The intact ...final-state proton is reconstructed in the ATLAS ALFA forward spectrometer, while charged particles from the dissociated system X are measured in the central detector components. The fiducial range of the measurement is −4.0 < log$_{10}$ξ < −1.6 and 0.016 < |t| < 0.43 GeV$^{2}$, where ξ is the proton fractional energy loss and t is the squared four-momentum transfer. The total cross section integrated across the fiducial range is 1.59 ± 0.13 mb. Cross sections are also measured differentially as functions of ξ, t, and ∆η, a variable that characterises the rapidity gap separating the proton and the system X . The data are consistent with an exponential t dependence, dσ/dt ∝ e$^{Bt}$ with slope parameter B = 7.65 ± 0.34 GeV$^{−2}$. Interpreted in the framework of triple Regge phenomenology, the ξ dependence leads to a pomeron intercept of α(0) = 1.07 ± 0.09.graphic not available: see fulltext
Experimental modal analysis of components of the LHC experiments is performed with the purpose of determining their fundamental frequencies, their damping and the mode shapes of light and fragile ...detector components. This process permits to confirm or replace Finite Element analysis in the case of complex structures (with cables and substructure coupling). It helps solving structural mechanical problems to improve the operational stability and determine the acceleration specifications for transport operations. This paper describes the hardware and software equipment used to perform a modal analysis on particular structures such as a particle detector and the method of curve fitting to extract the results of the measurements. This paper exposes also the main results obtained for the LHC Experiments.
A fully instrumented slice of the ATLAS detector was exposed to test beams from the SPS (Super Proton Synchrotron) at CERN in 2004. In this paper, the results of the measurements of the response of ...the barrel calorimeter to hadrons with energies in the range 20–350
GeV and beam impact points and angles corresponding to pseudo-rapidity values in the range 0.2–0.65 are reported. The results are compared to the predictions of a simulation program using the Geant 4 toolkit.
The differential cross section for the process $Z/\gamma^*\rightarrow ll$ ($l=e,\mu$) as a function of dilepton invariant mass is measured in pp collisions at $\sqrt{s}=$7 TeV at the LHC using the ...ATLAS detector. The measurement is performed in the $e$ and $\mu$ channels for invariant masses between 26 GeV and 66 GeV using an integrated luminosity of 1.6 fb$^{-1}$ collected in 2011 and these measurements are combined. The analysis is extended to invariant masses as low as 12 GeV in the muon channel using 35 pb$^{-1}$ of data collected in 2010. The cross sections are determined within fiducial acceptance regions and corrections to extrapolate the measurements to the full kinematic range are provided. Next-to-next-to-leading-order QCD predictions provide a significantly better description of the results than next-to-leading-order QCD calculations, unless the latter are matched to a parton shower calculation.
Novel cooling systems with very low material budget are being fabricated and studied. They consist of silicon wafers in which microchannels are etched and closed by bonding another wafer. This ...cooling option is being considered for future HEP detectors of the sLHC and linear colliders. It is currently under investigation as an option for the cooling of the NA62 Gigatracker silicon pixel detector and its front-end electronics where the microfabricated cooling plate would stand directly in the beam. In this particular case, microchannel cooling meets both the very aggressive X
0 (0.15%) specifications and the anticipated 2 W/cm
2 power dissipation by the active electronics.
The NA62 experiment at the CERN SPS is aimed at measuring the branching fraction of the ultrarare decay K+ → π+v with ~10% precision by collecting ~1013 kaon decays in two years of data taking. This ...amount of data will allow to carry out a wide program of searching for rare and forbidden (within the Standard Model) K+ and π0 decays, including sterile neutrinos, lepton flavor violating modes, exotic particles (e.g. "dark photons"). The expected performances of the NA62 setup will allow to improve existing limits for several decay modes.