Records |
Author |
Abgrall, N. et al; Cervera-Villanueva, A.; Escudero, L.; Monfregola, L.; Stamoulis, P. |
Title |
Time projection chambers for the T2K near detectors |
Type |
Journal Article |
Year |
2011 |
Publication |
Nuclear Instruments & Methods in Physics Research A |
Abbreviated Journal |
Nucl. Instrum. Methods Phys. Res. A |
Volume |
637 |
Issue |
1 |
Pages |
25-46 |
Keywords |
Time projection chamber; Drift chamber; Gas system; Micromegas; Neutrino oscillation |
Abstract |
The T2K experiment is designed to study neutrino oscillation properties by directing a high intensity neutrino beam produced at J-PARC in Tokai, Japan, towards the large Super-Kamiokande detector located 295 km away, in Kamioka, Japan. The experiment includes a sophisticated near detector complex, 280 m downstream of the neutrino production target in order to measure the properties of the neutrino beam and to better understand neutrino interactions at the energy scale below a few GeV. A key element of the near detectors is the ND280 tracker, consisting of two active scintillator-bar target systems surrounded by three large time projection chambers (TPCs) for charged particle tracking. The data collected with the tracker are used to study charged current neutrino interaction rates and kinematics prior to oscillation, in order to reduce uncertainties in the oscillation measurements by the far detector. The tracker is surrounded by the former UA1/NOMAD dipole magnet and the TPCs measure the charges, momenta, and particle types of charged particles passing through them. Novel features of the TPC design include its rectangular box layout constructed from composite panels, the use of bulk micromegas detectors for gas amplification, electronics readout based on a new ASIC, and a photoelectron calibration system. This paper describes the design and construction of the TPCs, the micromegas modules, the readout electronics, the gas handling system, and shows the performance of the TPCs as deduced from measurements with particle beams, cosmic rays, and the calibration system. |
Address |
[Birney, P.; Bojechko, C.; Fransham, K.; Gaudin, A.; Karlen, D.; Langstaff, R.; Lenckowski, M.; Myslik, J.; Poffenberger, P.; Roney, M.; Tvaskis, V.] Univ Victoria, Dept Phys & Astron, Victoria, BC, Canada, Email: karlen@uvic.ca |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
|
Language |
English |
Summary Language |
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Original Title |
|
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0168-9002 |
ISBN |
|
Medium |
|
Area |
|
Expedition |
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Conference |
|
Notes |
ISI:000289608000004 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
607 |
Permanent link to this record |
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Author |
Carbone, C.; Mena, O.; Verde, L. |
Title |
Cosmological parameters degeneracies and non-Gaussian halo bias |
Type |
Journal Article |
Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
Volume |
07 |
Issue |
7 |
Pages |
020 - 17pp |
Keywords |
power spectrum; redshift surveys; galaxy clusters; cosmological parameters from LSS |
Abstract |
We study the impact of the cosmological parameters uncertainties on the measurements of primordial non-Gaussianity through the large-scale non-Gaussian halo bias effect. While this is not expected to be an issue for the standard Lambda CDM model, it may not be the case for more general models that modify the large-scale shape of the power spectrum. We consider the so-called local non-Gaussianity model, parametrized by the f(NL) non-Gaussianity parameter which is zero for a Gaussian case, and make forecasts on f(NL) from planned surveys, alone and combined with a Planck CMB prior. In particular, we consider EUCLID- and LSST-like surveys and forecast the correlations among f(NL) and the running of the spectral index alpha(s), the dark energy equation of state w, the effective sound speed of dark energy perturbations c(s)(2), the total mass of massive neutrinos M-nu = Sigma m(nu), and the number of extra relativistic degrees of freedom N-nu(rel). Neglecting CMB information on f(NL) and scales k > 0.03h/Mpc, we find that, if N-nu(rel) is assumed to be known, the uncertainty on cosmological parameters increases the error on f(NL) by 10 to 30% depending on the survey. Thus the f(NL) constraint is remarkable robust to cosmological model uncertainties. On the other hand, if N-nu(rel) is simultaneously constrained from the data, the f(NL) error increases by similar to 80%. Finally, future surveys which provide a large sample of galaxies or galaxy clusters over a volume comparable to the Hubble volume can measure primordial non-Gaussianity of the local form with a marginalized 1-sigma error of the order Delta f(NL) similar to 2 – 5, after combination with CMB priors for the remaining cosmological parameters. These results are competitive with CMB bispectrum constraints achievable with an ideal CMB experiment. |
Address |
[Carbone, Carmelita] Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy, Email: carmelita.carbone@unibo.it |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000283573200010 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
347 |
Permanent link to this record |
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Author |
Baron, R.; Boucaud, P.; Dimopoulos, P.; Frezzotti, R.; Palao, D.; Rossi, G.; Farchioni, F.; Munster, G.; Sudmann, T.; Gimenez, V.; Herdoiza, G.; Jansen, K.; Lubicz, V.; Simula, S.; Michael, C.; Scorzato, L.; Shindler, A.; Urbach, C.; Wenger, U. |
Title |
Light meson physics from maximally twisted mass lattice QCD |
Type |
Journal Article |
Year |
2010 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
Volume |
08 |
Issue |
8 |
Pages |
097 - 41pp |
Keywords |
Lattice QCD; Quark Masses and SM Parameters; QCD |
Abstract |
We present a comprehensive investigation of light meson physics using maximally twisted mass fermions for N-f = 2 mass-degenerate quark flavours. By employing four values of the lattice spacing, spatial lattice extents ranging from 2.0 fm to 2.5 fm and pseudo scalar masses in the range 280 less than or similar to m(PS) less than or similar to 650MeV we control the major systematic effects of our calculation. This enables us to confront our N-f = 2 data with SU(2) chiral perturbation theory and extract low energy constants of the effective chiral Lagrangian and derived quantities, such as the light quark mass. |
Address |
[Baron, Remi; Boucaud, Phillip] Univ Paris 11, Phys Theor Lab, Ctr Orsay, F-91405 Orsay, France, Email: remi.baron@centraliens.net |
Corporate Author |
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Thesis |
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Publisher |
Springer |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1126-6708 |
ISBN |
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Medium |
|
Area |
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Expedition |
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Conference |
|
Notes |
ISI:000282367800036 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
348 |
Permanent link to this record |
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Author |
Belver, D.; Cabanelas, P.; Castro, E.; Garzon, J.A.; Gil, A.; Gonzalez-Diaz, D.; Koenig, W.; Traxler, M. |
Title |
Performance of the Low-Jitter High-Gain/Bandwidth Front-End Electronics of the HADES tRPC Wall |
Type |
Journal Article |
Year |
2010 |
Publication |
IEEE Transactions on Nuclear Science |
Abbreviated Journal |
IEEE Trans. Nucl. Sci. |
Volume |
57 |
Issue |
5 |
Pages |
2848-2856 |
Keywords |
Charge to width algorithm; fast amplifying and digitizing electronics; front-end electronics; HADES; time of flight; timing RPC |
Abstract |
A front-end electronics (FEE) chain for accurate time measurements has been developed for the new Resistive Plate Chamber (RPC)-based Time-of-Flight (TOF) wall of the High Acceptance Di-Electron Spectrometer (HADES). The wall covers an area of around 8 m(2) divided in 6 sectors. In total, 1122 4-gap timing RPC cells are read-out by 2244 time and charge sensitive channels. The FEE chain consists of 2 custom-made boards: a 4-channel Daughter BOard(DBO) and a 32-channel MotherBOard (MBO). The DBO uses a fast 2 GHz amplifier feeding a dual high-speed discriminator. The time and charge information are encoded, respectively, in the leading edge and the width of an LVDS signal. Each MBO houses up to 8 DBOs providing them regulated voltage supply, threshold values via DACs, test signals and, additionally, routing out a signal proportional to the channel multiplicity needed for a 1st level trigger decision. The MBO delivers LVDS signals to a multi-purpose Trigger Readout Board (TRB) for data acquisition. The FEE allows achieving a system resolution around 75 ps fulfilling comfortably the requirements of the HADES upgrade [1]. The commissioning of the whole RPC wall is finished and the 6 sectors are already mounted in their final position in the HADES spectrometer and ready to take data during the beam-times foreseen for 2010. |
Address |
[Belver, Daniel; Cabanelas, P.; Castro, E.; Garzon, J. A.] Univ Santiago Compostela, LabCAF, Santiago De Compostela 15782, Spain, Email: daniel.belver@usc.es |
Corporate Author |
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Thesis |
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Publisher |
Ieee-Inst Electrical Electronics Engineers Inc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0018-9499 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000283440400007 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
349 |
Permanent link to this record |
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Author |
Montanari, D. et al; Gadea, A. |
Title |
Probing the nature of particle-core couplings in Ca-49 with gamma spectroscopy and heavy-ion transfer reactions |
Type |
Journal Article |
Year |
2011 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
697 |
Issue |
4 |
Pages |
288-293 |
Keywords |
Multi-nucleon transfer; Gamma spectroscopy; Magnetic spectrometer; Particle-core coupling |
Abstract |
Neutron rich nuclei around Ca-48 have been measured with the CLARA-PRISMA setup, making use of Ca-48 on Ni-64 binary reactions, at 5.9 MeV/A. Angular distributions of gamma rays give evidence, in several transfer channels, for a large spin alignment (approximate to 70%) perpendicular to the reaction plane, making it possible to firmly establish spin and parities of the excited states. In the case of Ca-49, states arising from different types of particle-core couplings are, for the first time, unambiguously identified on basis of angular distribution, polarization and lifetime measurements. Shell model and particle-vibration coupling calculations are used to pin down the nature of the states. Evidence is found for the presence, in the same excitation energy region, of two types of coupled states, i.e. single particle coupled to either Ca-48 or Ca-50 simple configurations, and particle-vibration coupled states based on the 3- phonon of Ca-48. |
Address |
[Montanari, D.; Leoni, S.; Bocchi, G.; Bortignon, P. F.; Bracco, A.; Camera, F.; Colo, G.; Corsi, A.; Crespi, F. C. L.; Nicolini, R.] Univ Milan, Dipartimento Fis, Milan, Italy, Email: silvia.leoni@mi.infn.it |
Corporate Author |
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Thesis |
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Publisher |
Elsevier Science Bv |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000288300400005 |
Approved |
no |
Is ISI |
yes |
International Collaboration ![sorted by International Collaboration field, descending order (down)](img/sort_desc.gif) |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
542 |
Permanent link to this record |