Nuclear Physics

The first LHC pp collisions at centre-of-mass energies of 0.9 and 2.36 TeV were recorded by the CMS detector in December 2009. The trajectories of charged particles produced in the collisions were reconstructed using the all-silicon Tracker and their momenta were measured in the 3.8 T axial magnetic field. Results from the Tracker commissioning are presented including studies of timing, efficiency, signal-to-noise, resolution, and ionization energy. Reconstructed tracks are used to benchmark the performance in terms of track and vertex resolutions, reconstruction of decays, estimation of ionization energy loss, as well as identification of photon conversions, nuclear interactions, and heavy-flavour decays.

Radiosensitivity, the susceptibility of cells to ionizing radiation, plays a critical role in understanding the effects of radiation therapy and exposure on tissue health and regeneration. Identifying characteristics that predict how a patient may respond to radiotherapy enables clinicians to maximize the therapeutic window. Limited clinical data suggested a difference in male and female radiotherapy outcomes. Radiotherapy for gastrointestinal malignancy is still a challenge due to intestinal sensitivity to radiation toxicity. In this manuscript we demonstrated sex specific differences in intestinal epithelial radiosensitivity. In mice model of abdominal irradiation, we observed significant increase in oxidative stress and injury in male compared to female. Lgr5+ve intestinal stem cells from male mice showed higher sensitivity to radiation induced toxicity. However, sex specific differences in intestinal radiosensitivity are not dependent on sex hormone as we demonstrated similar se...

The full exploitation of the physics potential of an International Linear Collider (ILC) requires the development of a polarized positron beam. New concepts of polarized positron sources are based on the development of circularly polarized photon sources. The polarized photons create electron-positron pairs in a thin target and transfer their polarization state to the outgoing leptons. To achieve a high level of positron polarization the understanding of the production mechanisms in the target is crucial. Therefore a general framework for the simulation of polarized processes with Geant4 is under development. In this contribution the current status of the project and its application to a study of the positron production process for the ILC is presented.

This study investigates purely angular effects on photon buildup factors for slabs with optical thickness up to 10 mean free paths. Photon buildup factors are determined for different slabs, upon which monoenergetic photons between 50 keV and 10 MeV are incident at angles between 0 and 1.48 radians. As the incident angle is increased, the physical slab thickness is reduced to maintain a constant slant-path optical thickness relative to incident photons. This method identifies previously unexplored angular relationships between slab thickness and incident angle. Coupled electron/photon cross sections are used to account for secondary photon effects of bremsstrahlung and electron binding energies. The discrete ordinates code PARTISN is used to determine angular photon buildup factors for ten incident energies and ten incident angles for lead, iron, aluminum, and water slabs. Portions of these results are applicable to other slab geometry buildup studies.

The coherent density fluctuation model is employed to investigate the nuclear symmetry energy S(A), neutron pressure Po, and asymmetric compressibility Δk of Na isotopes. The relationship between the thickness of the neutron shell of the confined nucleus and the nuclear symmetry energy is discussed. When examining density-dependent nuclear symmetry energy properties, a significant difference is found in the direction followed by even (A = 20-32) and odd (A = 21-31) nuclei of sodium isotope chains. The global analysis also explores the relationship between nuclear symmetry energy and the thickness of neutron shells concerning the asymmetry of neutrons and protons. Furthermore, we establish a constraint on the relationship between the nuclear symmetry energy slope L ANM and Δk based on experimentally permissible values of the saturation line slope (the line connecting nuclear matter saturation points in neutron excess), along with a strong link between S(A) and L ANM .

Abstract. The coherent density fluctuation model is employed to investigate the nuclear symmetry energy S(A), neutron
pressure Po, and asymmetric compressibility Δk of Na isotopes. The relationship between the thickness of the neutron
shell of the confined nucleus and the nuclear symmetry energy is discussed. When examining density-dependent nuclear
symmetry energy properties, a significant difference is found in the direction followed by even (A = 20-32) and odd (A =
21-31) nuclei of sodium isotope chains. The global analysis also explores the relationship between nuclear symmetry
energy and the thickness of neutron shells concerning the asymmetry of neutrons and protons. Furthermore, we establish
a constraint on the relationship between the nuclear symmetry energy slope LANM and Δk based on experimentally
permissible values of the saturation line slope (the line connecting nuclear matter saturation points in neutron excess),
along with a strong link between S(A) and LANM.

Background: Radiotherapy increases survival in patients with glioblastoma. However, the prescribed dose is limited by unwanted side effects on normal tissue. Previous experimental studies have shown that FLASH radiotherapy (FLASH-RT) can reduce these side effects. Still, it is important to establish an equal anti-tumor efficacy comparing FLASH-RT to conventional radiotherapy (CONV-RT). Methods: Fully immunocompetent Fischer 344 rats with the GFP-positive NS1 intracranial glioblastoma model were irradiated with CONV-RT or FLASH-RT in one fraction of 20 Gy, 25 Gy or 30 Gy. Animals were monitored for survival and acute dermal side effects. The brains were harvested upon euthanasia and tumors were examined post mortem. Results: Survival was significantly increased in animals irradiated with CONV-RT and FLASH-RT at 20 Gy and 25 Gy compared to control animals. The longest survival was reached in animals irradiated with FLASH-RT and CONV-RT at 25 Gy. Irradiation at 30 Gy did not lead to increased survival, despite smaller tumors. Tumor size correlated inversely with irradiation dose, both in animals treated with CONV-RT and FLASH-RT. Acute dermal side effects were mild, but only a small proportion of the animals were alive for evaluation of those side effects. The dose response was similar for CONV-RT and FLASH-RT in the present model. Tumor size upon the time of euthanasia correlated inversely with the irradiation dose.

This paper comprehensively investigates performance of evolutionary algorithms for design optimization of shell and tube heat exchangers (STHX). Genetic algorithm (GA), firefly algorithm (FA), and cuckoo search (CS) method are implemented for finding the optimal values for seven key design variables of the STHX model. -NTU method and Bell-Delaware procedure are used for thermal modeling of STHX and calculation of shell side heat transfer coefficient and pressure drop. The purpose of STHX optimization is to maximize its thermal efficiency. Obtained results for several simulation optimizations indicate that GA is unable to find permissible and optimal solutions in the majority of cases. In contrast, design variables found by FA and CS always lead to maximum STHX efficiency. Also computational requirements of CS method are significantly less than FA method. As per optimization results, maximum efficiency (83.8%) can be achieved using several design configurations. However, these designs are bearing different dollar costs. Also it is found that the behavior of the majority of decision variables remains consistent in different runs of the FA and CS optimization processes.

A search for the standard model Higgs boson decaying to a W-boson pair at the LHC is reported. The event sample corresponds to an integrated luminosity of 4.9 fb−1 and 19.4 fb−1 collected with the CMS detector in pp collisions at $ \sqrt{s} $ = 7 and 8 TeV, respectively. The Higgs boson candidates are selected in events with two or three charged leptons. An excess of events above background is observed, consistent with the expectation from the standard model Higgs boson with a mass of around 125 GeV. The probability to observe an excess equal or larger than the one seen, under the background-only hypothesis, corresponds to a significance of 4.3 standard deviations for m H = 125.6 GeV. The observed signal cross section times the branching fraction to WW for m H = 125.6 GeV is $ 0.72_{-0.18}^{+0.20 } $ times the standard model expectation. The spin-parity J P = 0+ hypothesis is favored against a narrow resonance with J P = 2+ or J P = 0− that decays to a W-boson pair. This result prov...

The measurements of the differential elastic neutron cross-sections of carbon have been carried out at the Kyiv Research Reactor (KRR) using the neutron filter beam technique. Experimental set-up for detection of scattered neutrons has been installed at the eighth horizontal channel of the KRR. The quasi-mono-energetic neutron lines with mean energies 2, 59 and 133 keV were formed by composite filters. The measurements of the angle distribution of scattering neutrons on carbon samples were executed at angles 30 0 , 55 0 , 90 0 , 125 0 and 150 0 for three neutron energies. To determine the differential elastic neutron cross-section on carbon dσ/dΩ, the relative method of measurement was used. The isotope 208 Pb was used as a standard. The normalization factor, which is a function of detector efficiency, thickness of the carbon samples, thickness of the Pb-208 sample, geometry, etc., for each sample and for each filter energy has been obtained through Monte Carlo calculations by means of own codes. The results of measurements of the differential elastic neutron cross sections on carbon samples at reactor neutron filtered beams with energies 2, 59, and 133 keV have been compared with the known experimental data from database EXFOR/CSISRS.

The paper presents studies of Bose-Einstein Correlations (BEC) for pairs of like-sign charged particles measured in the kinematic range [Formula: see text] 100 MeV and [Formula: see text] 2.5 in proton collisions at centre-of-mass energies of 0.9 and 7 TeV with the ATLAS detector at the CERN Large Hadron Collider. The integrated luminosities are approximately 7 [Formula: see text]b[Formula: see text], 190 [Formula: see text]b[Formula: see text] and 12.4 nb[Formula: see text] for 0.9 TeV, 7 TeV minimum-bias and 7 TeV high-multiplicity data samples, respectively. The multiplicity dependence of the BEC parameters characterizing the correlation strength and the correlation source size are investigated for charged-particle multiplicities of up to 240. A saturation effect in the multiplicity dependence of the correlation source size parameter is observed using the high-multiplicity 7 TeV data sample. The dependence of the BEC parameters on the average transverse momentum of the particle p...

We investigate the quantization of even-dimensional topological actions of Chern-Simons form which were proposed previously. We quantize the actions by Lagrangian and Hamiltonian formulations à la Batalin, Fradkin and Vilkovisky. The models turn out to be infinitely reducible and thus we need an infinite number of ghosts and antighosts. The minimal actions of Lagrangian formulation which satisfy the master equation of Batalin and Vilkovisky have the same Chern-Simons form as the starting classical actions. In the Hamiltonian formulation we have used the formulation of cohomological perturbation and explicitly shown that the gauge-fixed actions of both formulations coincide even though the classical action breaks Dirac's regularity condition. We find an interesting relation that the BRST charge of Hamiltonian formulation is the odd-dimensional fermionic counterpart of the topological action of Chern-Simons form. Although the quantization of two dimensional models which include both bosonic and fermionic gauge fields are investigated in detail, it is straightforward to extend the quantization into arbitrary even dimensions. This completes the quantization of previously proposed topological gravities in two and four dimensions.

Recent high-energy collider data reveal anomalous pre-collision trajectory deviations in subatomic particles. These deviations, which resist explanation via Standard Model dynamics or localized field influence, suggest the presence of non-visible geometric attractors — potentially higher-dimensional constraint surfaces. We propose these attractors are manifestations of memory-resonant coherence curvature embedded within the Δν_f lattice: a neutrino-based informational scaffold proposed in the NDISH-II framework. In this model, particle behavior is not fully stochastic but guided by field curvature shaped by historical coherence events, encoded into the lattice. This addendum outlines the mechanism by which the neutrino field may act as a pre-causal attractor grid, reframing causality as the unfolding of memory-guided field tension.

India-based Neutrino Observatory (INO) collaboration has proposed a 50 kTons magnetised iron calorimeter (ICAL), whose primary goals are to precisely determine oscillation parameters of the atmospheric neutrinos, to study matter effects on the oscillations and finally to use it as a long baseline detector for the neutrino beams. Good tracking and energy resolutions, good directionality (translating to a time resolution of better than a ns) and charge identification of the detecting particles are the essential requirements of ICAL detector. The ICAL detector will cover an area of about 100,000 m 2 and will use about 30,000 glass Resistive Plate Chambers (RPCs) of about 2 m × 2 m in area as active detector elements. An aggressive R&D program to develop and characterise RPCs operating in the avalanche mode was undertaken. We will describe our R&D efforts towards developing these devices and will present the results of their characterisation studies.

William Wenzel, and myself. The Fermilab group included Rolland Johnson, Craig Moore, Marshall Mugge, and Robert Shafer. The colleagues from Princeton were George Gollin, Frank Shoemaker, and Pamela Surko. I am indebted to my faculty advisor, Leroy Kerth, for providing me with guidance and motivation. I am grateful to Mark Strovink for his in sight and innumerable suggestions which often provided the driving force for this research. The reliable counsel and support of my fellow gradu ate students, George Gollin, Tom Markiewicz and Peter Meyers, was great ly appreciated. The technical support of this experiment was outstanding. Special thanks go to Fred Goozen and his remarkable team at Berkeley: "Ducky" Lucas, Tim Nuzum, and Tom Weber. John Caron wrote much excellent software for the data analysis. Garvie Hale provided technical exper tise at Fermilab. Mirriam Schwartz and others in the Technical Illus tration department put a lot of effort into the figures for this thesis. Teri Martin prepared the early text of this manuscript and Donna Vercelli produced the final document with admirable dedication. I am grateful to Wai-Yee Keung of Brookhaven Lab for discussions about the rare multimuon states. The Neutrino department at Fermilab provided much support for this experiment. The staffs of the computer centers at Berkeley and Fermilab were most cooperative in enabling us to iv analyze our data. This work was supported by the High Energy Physics Division of the U.S. Department of Energy under contract Nos. W-7405-Eng-48, DE-AC02-76ER03072, and EY-7S-C-02-3000. Finally, I would like to thank my parents, who gave me the finest education and endless encouragement. V

William Wenzel, and myself. The Fermilab group included Rolland Johnson, Craig Moore, Marshall Mugge, and Robert Shafer. The colleagues from Princeton were George Gollin, Frank Shoemaker, and Pamela Surko. I am indebted to my faculty advisor, Leroy Kerth, for providing me with guidance and motivation. I am grateful to Mark Strovink for his in sight and innumerable suggestions which often provided the driving force for this research. The reliable counsel and support of my fellow gradu ate students, George Gollin, Tom Markiewicz and Peter Meyers, was great ly appreciated. The technical support of this experiment was outstanding. Special thanks go to Fred Goozen and his remarkable team at Berkeley: "Ducky" Lucas, Tim Nuzum, and Tom Weber. John Caron wrote much excellent software for the data analysis. Garvie Hale provided technical exper tise at Fermilab. Mirriam Schwartz and others in the Technical Illus tration department put a lot of effort into the figures for this thesis. Teri Martin prepared the early text of this manuscript and Donna Vercelli produced the final document with admirable dedication. I am grateful to Wai-Yee Keung of Brookhaven Lab for discussions about the rare multimuon states. The Neutrino department at Fermilab provided much support for this experiment. The staffs of the computer centers at Berkeley and Fermilab were most cooperative in enabling us to iv analyze our data. This work was supported by the High Energy Physics Division of the U.S. Department of Energy under contract Nos. W-7405-Eng-48, DE-AC02-76ER03072, and EY-7S-C-02-3000. Finally, I would like to thank my parents, who gave me the finest education and endless encouragement. V

We report a new measurement of the B-meson semileptonic decay momentum spectrum that has been made with a sample of 9.4 fb -1 of e + e -data collected with the CLEO II detector at the Υ(4S) resonance. Electrons from primary semileptonic decays and secondary charm decays were separated by using charge and angular correlations in Υ(4S) events with a high-momentum lepton and an additional electron. We determined the semileptonic branching fraction to be B(B → Xe + ν e ) = (10.91 ± 0.09 ± 0.24)% from the normalization of the electron-energy spectrum. We also measured the moments of the electron energy spectrum with minimum energies from 0.6 GeV to 1.5 GeV.

A search for the decay K S → π 0 γγ has been made using the NA48 detector at the CERN SPS. Using data collected in 1999 during a 40-hour run with a high-intensity K S beam, an upper limit for the branching ratio BR K S → π 0 γγ, z ≥ 0.2 < 3.3 × 10 -7 has been obtained at 90% confidence level, where z = m 2 γγ /m 2 K 0 .

Using data collected at the ψ(3770) resonance with the CLEO-c detector at the Cornell e + e - storage ring, we present improved measurements of the absolute branching fractions of D + decays to K0 e + ν e , π 0 e + ν e , K * 0 e + ν e , and ρ 0 e + ν e , and the first observation and absolute branching fraction measurement of D + → ωe + ν e . We also report the most precise tests to date of isospin invariance in semileptonic D 0 and D + decays.

Using a sample of 9.6 × 10 6 BB meson pairs collected with the CLEO detector, we have fully reconstructed 135 B 0 → ψ (′) K 0 S and 526 B + → ψ (′) K + candidates with very low background. We fitted the ψ (′) K invariant mass distributions of these B meson candidates and measured the masses of the neutral and charged B mesons to be The precision is a significant improvement over previous measurements.

Fermi lab have yielded more than 8xl0 4 e'vents with two muons in the final state. After reconstruction and cuts, the data contain 20 072 events with (81±10)% attributed to the diffractive production of charmed states decaying to muons. The cross section for diffractive charm +1•9 muoproduction is 6.9_ 1 • 4 nb where the error includes systematic uncertainties. Extrapolated to Q 2 =0 with o(Q 2 )=o(O)(l+Q2JA2)-2, the effective cross +180 +200 section for 178 (100) GeV photons is 750_130 (560-120) nb and the parameter A is 3.3±0.2 (2.9±0.2) GeV/c. The \! dependence of the cross section is similar to that of the photon-gluon-fusion model. Okubo-Zweig-Iizuka selection rules and unitarity allow the muon data to set a 90% confidence lower limit on the ~N total cross section of 0.9 mb. A first determination of the structure function F 2 (cc) for diffractive charm production indicates that charm accounts for approximately 1/3 of the scale-noninvariance observed in inclusive muon-nucleon scattering at low Bjorken x.

We have measured the inclusive deep inelastic scattering of muons on nucleons in iron using beams of 93 and 215 GeV muons. To perform this measurement, we have built and operated the Multimuon Spectrometer (MMS) in the muon beam at Fermilab. Using the known form of the radiativelycorrected electromagnetic cross section, we extract the struc-,5,,, ture function F 2 (x, Q 2 ) with a typical precision of 2% over the' range 5 < Q 2 < 200 GeV 2 fc 2 • We compare our mea-Measurement of the Nucleon Structure Function in Iron surements to the predictions of lowest order quantum chro-Using 215-and 93-GeV Muons modynamics (QCD) and find a best fit value of the QCD scale parameter ALo = 230 ± 40"'"t ± so•ll•t Mev I c, assuniing

Using the CLEO II detector operating at the Cornell Electron Storage Ring ͑CESR͒ e ϩ e Ϫ collider, we have measured the structure functions in the decay ϯ → ϯ 0 0 , based on a sample corresponding to 4ϫ10 6 produced -pair events. We determine the integrated structure functions, which depend only on the three pion invariant mass, as well as the structure functions differential in the Dalitz plot variables. We extract model independent limits on non-axial-vector contributions from the measured structure functions as less than 16.6% of the total branching fraction, at the 95% confidence level. Separating the non-axial-vector contributions into scalar and vector contributions, we measure that scalars ͑vectors͒ contribute with less than 9.4% ͑7.3%͒ to the total branching fraction, at the 95% confidence level.

We measure the primary lepton momentum spectrum in B → Xℓν decays, for p ℓ ≥ 1.5 GeV/c in the B rest frame. From this, we calculate various moments of the spectrum. In particular, we find R 0 ≡ 1.7 GeV (dΓ/dE sl )dE ℓ / 1.5 GeV (dΓ/dE sl )dE ℓ = 0.6187 ± 0.0014 stat ± 0.0016 sys and R 1 ≡ 1.5 GeV E ℓ (dΓ/dE sl )dE ℓ / 1.5 GeV (dΓ/dE sl )dE ℓ = (1.7810 ± 0.0007 stat ± 0.0009 sys ) GeV. We use these moments to determine non-perturbative parameters governing the semileptonic width. In particular, we extract the Heavy Quark Expansion parameters Λ = (0.39±0.03 stat ±0.06 sys ±0.12 th ) GeV and λ 1 = (-0.25 ± 0.02 stat ± 0.05 sys ± 0.14 th ) GeV 2 . The theoretical constraints used are evaluated through order 1/M 3 B in the non-perturbative expansion and β 0 α 2 s in the perturbative expansion. We use these parameters to extract |V cb | from the world average of the semileptonic width and find |V cb | = (40.8 ± 0.5 Γ sl ± 0.4 (λ 1 , Λ)exp ± 0.9 th ) × 10 -3 . In addition, we extract the short range b-quark mass m 1S b = (4.82 ± 0.07 exp ± 0.11 th ) GeV/c 2 . Finally, we discuss the implications of our measurements for the theoretical understanding of inclusive semileptonic processes.

An experimental technique using the surrogate reaction method has been developed to measure fission probabilities of actinides as a function of angular momentum state of the fissioning nucleus near the fission barrier. In this work, the 240 Pu(α, αf ) reaction was used as a surrogate for 239 Pu(n, f ). An array of 12 silicon telescopes positioned at 10 degree intervals from 40 to 140 degrees detect the outgoing reaction particle for identification and measurement of the excitation energy. The angular momentum state is determined by measuring the angular distribution of fission fragments. The expected distributions are predicted from the Wigner d function. An array of 50 photovoltaic (solar) cells detects fission fragments with 10-degree granularity. The solar cells are sensitive to fission fragments but have no response to light ions. Relative contributions from different angular momentum states are extracted from the measured distributions and compared across all α particle scattering angles to determine fission probability at a specific angular momentum state. The first experiment using this technique was recently completed using 37 MeV α particles incident on 240) Pu. First results will be discussed.

We study the hydrodynamical expansion of a hot and baryon-dense quark fluid coupled to classical real-time evolution of the long wavelength modes of the chiral field. Significant density inhomogeneities develop dynamically when the transition to the symmetry-broken state occurs. We find that the amplitude of the density inhomogeneities is larger for expansion trajectories crossing the line of first-order transitions than for crossovers, which could provide some information on the location of a critical point. A few possible experimental signatures for inhomogeneous decoupling surfaces are mentioned briefly.

The author’s lecture courses available online seem to be overloaded with demonstration materials. Therefore, some of these materials, especially those relating to various experiments, are presented here separately in the form of an ATLAS that can be considered as a supplement to the lectures.

This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the 2×10^{-4}≲|Δm_{41}^{2}|≲0.3  eV^{2} mass range. The resulting limits on sin^{2}2θ_{14} are improved by approx imately a factor of 2 over previous results and constitute the most stringent constraints to date in the |Δm_{41}^{2}|≲0.2  eV^{2} region.

Nuclear energy is considered a clean, reliable, and an inexhaustible energy source for power generation. Nuclear power is harnessed from nuclear fission reactions in a dedicated power plant. The by-products (produced in the nuclear power plant) are radioactive and pose a threat to the environment. The safe disposal of nuclear waste is vital to ensure the sustainable use of the nuclear energy. The immobilization of radioactive waste before final disposal is essential for the interim storage and transportation. This review summarizes the recent work on glass, ceramics, and glass-ceramics matrices to immobilize high-level waste. The synthesis methods, leaching behavior, and radiation resistance of matrices are discussed briefly.

The SLAC Linac can deliver damped bunches with ILC parameters for bunch charge and bunch length to End Station A. A 10Hz beam at 28.5 GeV energy can be delivered there, parasitic with PEP-II operation. We plan to use this facility to test prototype components of the Beam Delivery System and Interaction Region. We discuss our plans for this ILC Test Facility and preparations for carrying out experiments related to collimator wakefields and energy spectrometers. We also plan an interaction region mockup to investigate effects from backgrounds and beam-induced electromagnetic interference.

The production of medical radionuclides is one of the research activities carried out in the framework of the SPES (Selective Production of Exotic Species) project under the completion stage at the Legnaro National Laboratories of the National Institute for Nuclear Physics (INFN-LNL). The heart of SPES is the 70-MeV proton cyclotron having a dual-beam extraction, installed and commissioned in a new building equipped with ancillary laboratories currently under construction. The SPES main goal is the realization of an advanced ISOL (Isotope Separation On-Line) facility to produce re-accelerated exotic ion beams for fundamental nuclear physics studies. The cyclotron double-beam extraction system allows to simultaneously carry out applied research, such as radionuclides production for medicine (SPES-γ ). This paper summarizes the results obtained with the interdisciplinary projects LARAMED (LAboratory of RAdionuclides for MEDicine) and ISOLPHARM (ISOL technique for radioPHARMaceuticals). The first one, based upon the direct activation method, is focused on the production of the radionuclides under the spotlight of the international community (e.g., 99m Tc, 67 Cu, 52/51 Mn, 47 Sc and Tb isotopes), from the nuclear cross-section measurements up to the preclinical studies. The other one exploits the ISOL technique for the development and production of radioisotopes with higha e-mail:

We study the flux tube junctions in the limit of large magnetic flux. In this limit the flux tube becomes a wall vortex which is a wall of negligible thickness (compared to the radius of the tube) compactified on a cylinder and stabilized by the flux inside. This wall surface can also assume different shapes that correspond to soliton junctions. We can have a flux tube that ends on a wall, a flux tube that ends on a monopole and more generic configurations containing all three of them. In this paper we find the differential equations that describe the shape of the wall vortex surface for these junctions. We will restrict to the cases of cylindrical symmetry. We also solve numerically these differential equations for various kinds of junctions. We finally find an interesting relation between soliton junctions and dynamical systems.

We study the Abrikosov-Nielsen-Olesen multi-vortices. Using a numerical code we are able to solve the vortex equations with winding number up to n = 25, 000. We can thus check the wall vortex conjecture previously made in . The numerical results show a remarkable agreement with the theoretical predictions.

We study some properties of topological Chern-Simons vortices in 2 + 1 dimensions. As has already been understood in the past, in the large magnetic flux limit, they are well described by a Chern-Simons domain wall, which has been compactified on a circle with the symmetric phase inside and the asymmetric phase on the outside. Our goal is two-fold. First we want to explore how the tension depends on the magnetic flux discretized by the integer n. The BPS case is already known, but not much has been explored about the non-BPS potentials. A generic renormalizable potential has two dimensionless parameters that can be varied. Variation of only one of them lead to a type I and type II vortex, very similar to the Abrikosov-Nielsen-Olesen (ANO) case. Variation of both the parameters leads to a much richer structure. In particular we have found a new type of vortex, which is type I-like for small flux and then turns type II-like for larger flux. We could tentatively denote it a type III vortex. This results in a stable vortex with number of fluxes which can be greater than one. Our second objective is to study the Maxwell-Chern-Simons theory and and understand how the large n limit of the CS vortex is smoothly connected with the large n limit of the ANO vortex. ⋄ bolognesi(at)physics.umn.edu ♮ gudnason(at)df.unipi.it

We study a class of N = 1 supersymmetric U(N) gauge theories and find that there exist vacua in which the low-energy magnetic effective gauge group contains multiple nonabelian factors, i SU(r i ), supported by light monopoles carrying the associated nonabelian charges. These nontrivially generalize the physics of the so-called r-vacua found in softly broken N = 2 supersymmetric SU(N) QCD, with an effective lowenergy gauge group SU(r) × U(1) N -r . The matching between classical and quantum (r 1 , r 2 , . . .) vacua gives an interesting hint about the nonabelian duality.