54722971
Study of solar neutrinos with the 600 t liquid argon ICARUS detector
Abstract The ICARUS time projection chamber can yield sound information on 8 B solar neutrinos. Owing to the high-energy resolution and the good capability of event reconstruction it can make a contribution to our understanding of neutrino intensities and their energy spectrum. Moreover, the MSW oscillation probability for sterile and active neutrinos can be well studied because both elastic scattering by electrons and absorption reaction on argon nuclei can be measured independently. The main problem in detecting the low-energy neutrino interactions arises from the environmental radioactivity. In the present work we study by Monte Carlo simulation the topology and the rates of the events, induced by neutrinos and background neutrons, in a 470 t (fiducial mass) liquid-argon TPC detector. For neutrino interactions we use the standard solar model BP98 and the recent experimental confirmation of the shell model computation of absorption cross section. The noise is estimated from new data on natural neutron background, collected in the hall C of the Gran Sasso laboratory. It is confirmed that, with a relatively modest neutron shielding and particular off-line event triggers, the weight of spurious events can be made to have little influence on the ICARUS solar neutrino measurement. Indeed, we expect 6 (26) background events per year in the 212 (759) elastic scattering (absorption reaction) sample.
123594822
Transfer matrices of dipoles with bending radius variation
With the increasing demand of high brightness in light source, the uniform dipole can not meet the needs of low emittance, and thus the dipole with bending radius variation is introduced in this paper. The transfer matrix of a non-uniform dipole whose bending radius is linearly changed is chosen as an example and a very simple calculation formula of non-uniform dipole transfer matrices is given. The transfer matrices of some common profile non-uniform dipoles are also listed. The comparison of these transfer matrices and the matrices calculated with slices method verifies the numerical accuracy of this formula. This method can make the non-uniform beam dynamic problem simpler, very helpful for emittance research and lattice design with non-uniform dipoles.
55843797
LATTICE DESIGN FOR THE BEPCII STORAGE RING
BEPCII, the upgrading project of the BEPC, has been being designed with a luminosity of 10 33 cm -2 s -1 at the J/ψ energy. It still keeps the potential to provide beams as a synchrotron radiation (SR) facility. The storage rings for collision contain a positron and an electron ring and the ring for dedicated SR uses the outer parts of the two rings. To fit all the conditions either on beam or on space limit, lattices are carefully designed for both high energy physics and SR experiments with sufficient dynamic apertures and high efficiencies for injection. The features of the lattices are also discussed in the paper. 1 DESIGN REQUIREMENTS BEPCII is an upgrade project of the Beijing ElectronPositron Collider (BEPC), in which a new inner ring will be installed inside the old one. It will provide colliding beams with the center-of-mass energy from 1.0GeV×2 to 2.0GeV×2 and also the dedicated synchrotron radiation beam with 2.5 GeV. For the colliding beams the luminosity is optimized at 1.89 GeV with 1×10 33 cm -2 s -1 . For the dedicated synchrotron radiation beam, the current is 250 mA with an emittance as low as possible. There have been several beam-lines in the BEPC for the synchrotron radiation experiments, so the current bending magnets and insertion devices in the southern region have to be fixed at their present positions. In order to increase the average luminosity, the “topoff” injection scheme up to 1.89 GeV is adopted. This requires that the injection and collision optics must be the same. The main parameters are shown in Tables 1 and 2.
56470793
DESIGN OF BEAM TRANSPORT LINE FROM RCS TO TARGET FOR CSNS
China Spallation Neutron Source (CSNS) uses the high energy proton beam to strike the Tungsten target to generate neutrons through spallation reaction. The proton beam is extracted from the Rapid Cycling Synchrotron (RCS), whose beam power reaches 100 kW. For the sake of target lifetime, beam distribution at the target surface is required as uniform as possible. Nonlinear beam density redistribution method with two octupole magnets has been studied. Also some simulation and theoretical calculation have been done. According to the simulation result, the beam density at the target is optimized and the beam loss is under control.
124075894
General conditions for self-cancellation of geometric aberrations in a lattice structure
In this paper we will discuss the general conditions for self-cancellation of geometric aberrations in an uncoupled or even coupled lattice structure. The self-cancellation conditions show that - I transformer even noninterleaved multipoles is not necessary. We will also give two examples for sextupole case to specify the application.
60626146
ILC Reference Design Report: ILC Global Design Effort and World Wide Study
123128473
On the systematic behaviour of the intermittency-indices in nuclear interactions
M.I. Adamovich a, M.M. Aggarwal b, Y.A. Alexandrov a, N.P. Andreeva c, Z.V. Anson c, R. Arora b, F.A. Avetyan d, S.K. Badyal e, E. Basova f, K.B. Bhalla g, A. Bhasin e, V.S. Bhatia b, V.G. Bogdanov h, V.I. Bubnov c, T.H. Burnett i, X. Cai J, I.Y. Chasnikov c, L.P. Chernova k, M.M. Chernyavski a, B. Dressel ~, G.Z. Eligbaeva c, L.E. Eremenko ~, E.M. Friedlander m, A.S. Gaitinov ~, E.R. Ganssauge ~, S. Garpman ", S.G. Gerassimov a, j. Grote i, K.G. Gulamov k, S.K. Gupta g, V. Gupta e, H.H. Heckrnan ~, H. Huang J, B. Jakobsson ", B. Judek o, S. Kachroo e, F.G. Kadyrov k, G.S. Kalyachkina c, E.K. Kanygina ~, M. Karabova P, G.L. Kaul e, M. Kaur b, S.P. Kharlamov a, T. Koss i, S.A. Krasnov P, V. Kumar g, P. Lal g, V.G. Larionova a, V.N. Lepetan ~, P.J. Lindstrom m, L.S. Liu J, S. Lokanathan g, J. Lord i, N.S. Lukicheva k, S.B. Luo q, L.K. Mangotra e, N.A. Marutyan d, N.V. Maslennikova ", I.S. Mittra b, S. Mookerjee g, C. Mueller ~, H. Nasrulaeva f, S.H. Nasyrov f, V.S. Navotny k, G.I. Orlova a, I. Otterlund n, H.S. Palsania g, N.G. Peresadko a, N.V. Petrov f, V.A. Plyushchev h, W.Y. Qian J, R. Raniwala g, S. Raniwala g, N.K. Rao ~, V.M. Rappoport a, J.T. Rhee ~, N. Saidkhanov k, N.A. Salmanova ~, L.G. Sarkisova d, V.R. Sarkisyan d, W. Schulz ~, G.S. Shabratova P, T.I. Shakhova ~, B. Singh b, D. Skelding i, K. SSderstrSm ", Z.I. Solovjeva h, E. Stenlund n, S.C. Strausz i, J.F. Sun r, L.N. Svechnikova k, K.D. Tolstov P, M.I. Tretyakova a, T.P. Trofimova r, U. Tuleeva r, S. Vokal P, H.Q. Wang J, Z.Q. Weng r, R.J. Wilkes i, G.F. Xu s, D.H. Zhang q, P.Y. Zheng s, S.I. Zhochova k, D.C. Zhou J and J.C. Zhou J
120005485
STUDY OF ANGULAR DISTRIBUTION OF HELIUM PROJECTILE FRAGMENTS IN INTERACTIONS OF 200 A GeV 32S IONS WITH EMULSION NUCLEI
This paper presents data on the emission of helium fragments due to break up of 200 A GeV 32S ions in collision with emulsion nuclei. A total of 499 minimum bias events have been studied in an emulsion stack and 97 events in emulsion chambers. Emission angles of He fragments have been measured with high precision. This data has been compared with data of breakup of heavier as well as lighter projectiles and we observe that the value of the momentum spread, σ(p), increases with increasing projectile mass. The bulk part of the helium emission is consistent with a single source for helium fragments with an average excitation energy of (9.1±0.9) MeV. A tail of a few (<1%) He fragments with higher momenta is observed.
122692421
Review of recent results on particle production from EMU01
Abstract The EMU01 Collaboration has employed emulsion chamber and pellicle detectors to accumulate a large database of heavy nucleus interactions. Samples include both minimum bias and central collisions, analyzed in a uniform manner to extract multiplicities and angular distributions of charged particles and nuclear fragments. We find that the main features of these distribution are well represented by geometrical superposition models. A unique feature of EMU01 is the use of emulsion chambers with thin foil targets to observe produced particle angular distributions with exceptionally high precision, permitting extension of fluctuations and correlations analyses beyond the resolution limits imposed by other experimental techniques. The data are generally well reproduced by interaction simulations such as FRITIOF (the Lund monte carlo for nuclear collisons) which include only conventional physics effects. However, the analysis of fluctuations and correlations via factorial moment and cumulant techniques yields some suggestive results which require further investigation, both by continued analysis of existing data and from Au and Pb beam exposures scheduled for the next few years.
120438611
Pseudorapidity distributions and correlations in central 16O interactions at 200 A GeV
Here we present results on charged hadron production in an experiment using tracking detectors with the highest possible spatial resolution: emulsion chambers. A sample of the most central collisions will be compared to the predictions of the Lund Model, which does an accurate job of representing conventional (non−quark−gluon plasma) physics in nuclear reactions. We can use the high resolution of our detectors to examine spatial correlations in several ways. In particular, the radial size of the particle formation region can be estimated using pion interferometry techniques.  (AIP)
116009345
Measurements of $\psi^\prime \to \bar{p} K^+ \Sigma^0$ and $\chi_{cj} \to \bar{p} K^+ \Lambda$
Using a sample of 1.06 x 10(8) psi' mesons collectedwith the BESIII detector at the BEPCII e(+)e(-) collider and chi(cJ) mesons produced via radiative transitions from the psi', we report the first observation for psi' -> (p) over barK(+)Sigma(0) + c.c. (charge conjugate), as well as improved measurements for the chi(cJ) hyperon decays chi(cJ) -> (p) over barK(+) Lambda + c.c. The branching fractions are measured to be B(psi' -> (p) over barK(+) Sigma(0) + c.c) = (1.67 +/- 0.13 +/- 0.12) x 10(-5), B(chi(c0) -> (p) over barK(+) Lambda + c.c) = (13.2 +/- 0.3 +/- 1.0) x 10(-4), B(chi(c1) -> (p) over barK(+) Lambda + c.c) = (4.5 +/- 0.2 +/- 0.4) x 10(-4), and B(chi(c2) -> (p) over barK(+) Lambda + c.c) = (8.4 +/- 0.3 +/- 0.6) x 10(-4), where the first error is statistical, and the second is systematic. In the decay of chi(c0) -> (p) over barK(+) Lambda + c.c:, an anomalous enhancement near threshold is observed in the invariant mass distribution of (p) over bar Lambda + c.c:, which cannot be explained by phase space. DOI: 10.1103/PhysRevD.87.012007