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## Runge-Lenz vector and Stark effect in Calogero-Coulomb problem

We show that deformation N-dimensional (Euclidean, spherical and hyperbolic) Coulomb system by the patential of rational Calogero model preserves superintegrability property of Coulomb problem. Then we find explicit expression of the Runge-Lenz vector and symmetry algebra of rational Calogero-Coulomb problem, formulated in terms of Dunkl operators. We find that they are proper deformations of their Coulomb counterparts. This observation permits to claim that most of properties of Coulomb and oscillator systems can be lifted to their Calogero-extended analogs by the proper replacement of momenta by Dunkl momenta operators. Particularly , we show that N-dimensional Calogero-Coulomb system preserves integrability property in the presence of Stark term, and construct its complete set of constants of motion. We find, that in parabolic coordinates the systems admits complete separation of variables for N=2,3 and partial ones for $N>3$. The system possesses linear Stark effect and find its explicit expression.Finally, we show, that two-center Calodjero-Coulomb problem is also integrable systems, which admits, in elliptic coordinates, the complet separation of variables for N=2,3 and partial ones for N>3.

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## Neutrinos and the Quantum Universe….. going International

Neutrinos are the most numerous and enigmatic particles with mass in the universe by far. They have incredibly small masses, so small that the Higgs mechanism may not be the primary source of mass for neutrinos. We do not know the absolute masses of neutrinos, nor the mass ordering of the neutrino flavors. We know only the mass differences that arise from the fact that neutrinos have been shown to oscillate between different flavors, however with remarkably different properties from quark mixing. Neutrinos play a crucial role in the structural evolution of the universe. We do not know whether there are more than 3 types of neutrinos or whether the known 3 types have non-standard interactions. We also do not know to what extent neutrinos contribute to the matter-antimatter asymmetry in the universe. Many of these questions can be addressed by a large, accelerator based neutrino experiment. A new collaboration has just been formed with over 140 institutions from around the world. DUNE (Deep Underground Neutrino Experiment) is a proposed gigantic 40 kiloton (fiducial volume) liquid argon detector to be located deep underground in the Sanford Underground Research Facility in South Dakota, with a fine-grained near detector at Fermilab.. Neutrinos are incredibly weakly interacting, and all accelerator based neutrino experiments are statistics limited. A newly upgraded accelerator complex at Fermilab is planned that can deliver 1.2 MW of beam power on target by 2025, and 2.4 MW several years later. Major platforms for R&D are being constructed at CERN and ...

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## Laser Communication in Space, developments at ESA

The first technology developments for optical satellite communication systems, which started in Europe more than 30 years ago, were based on CO2 laser systems. However, CO2 laser technology is not useful in space and when reliable laser-diodes became available ESA developed SILEX (the world-first optical inter-satellite communication link experiment) a data relay link between an Earth observation satellite (SPOT-4) and a geostationary satellite (ARTEMIS). Since it’s commissioning in 2001, the date relay system has been used extensively, also by external customers such as the Japanese OICETS satellite and by LOLA, a French aircraft to ARTEMIS communication experiment. However SILEX, being the first technology demonstration, was not able to compete with RF technology in terms of mass and data rate and a second generation of laser communication technology has been developed by the German Space Agency (DLR). The mass of the new optical terminals has been decreased from 160kg to 35kg and data rates increased from 50Mbps to 5600Mbps. Two such terminals have been launched on the TerraSAR-X and NFIRE satellites in 2007 into low Earth orbit and demonstrated over link distances up to 6000km. The next evolution of these terminals has an extended range of up to 45000km and will be used for the new European Data Relay System (EDRS) first serving the Sentinel satellites of the European Copernicus initiative. In addition laser communication experiments have been performed in 2013 with NASA’s LADEE satellite from lunar orbit and with the OPALS terminal from the ISS in 2014. The paper will ...

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## LNF Mini-Workshop Series: International Year of Light 2015

Year 2015 was proclaimed as the International Year of Light and Light-based Technologies (IYL 2015). Light plays a vital role in our daily lives and is an imperative cross-cutting discipline of science in the 21st century. It has revolutionized medicine, opened up international communication via the Internet, and continues to be central to linking cultural, economic and political aspects of the global society. In this contest the LNF Seminars Committee organizes a Mini-Workshop on the afternoon of May 12 in which, after a general introductory talk on the importance and motivation of this celebration, the main focus will be given to the major space applications of light,namely laser communications developed by the European Space Agency and laser tracking of special satellites used to define the center of mass of the Earth (the so-called ‘geocenter’).

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## 3rd European Lunar Symposium

The 3rd European Lunar Symposium will take place in the Bruno Touschek Auditorium, at LNF-INFN (see map). The program will consist of the following events: May 12th: – The registration desk will open at the ELS venue at 2:30pm and close at 7pm. – Visit to the SCF_Lab space test laboratory (http://www.lnf.infn.it/esperimenti/etrusco/) from 5pm to 7pm. Since this is a restricted clean-room facility up to 3 groups of 10 people will be accepted on a first come – first served basis. Please, send an email to: els2015infn@gmail.com. NEW: Requests for visiting the SCF_Lab are now closed. – Welcome Reception with food and drinks from 7pm to 8pm. May 13th: – ELS scientific program; lunch, 2 coffee breaks (mid-morning and mid-afternoon); Social Dinner. May 14th: – ELS Scientific program; lunch, 2 coffee breaks (mid-morning and mid-afternoon). All of the above is included in the symposium fee. In addition to the Symposium, the following events will take place: – IYL-2015 Seminars on May 12th: the INFN-LNF Seminar Committee (chaired by Manuela Boscolo) is happy to invite the ELS participants to attend seminars dedicated to the celebrations of the "International Year of Light – 2015 (IYL-2015), that will take place at the ELS venue from 3pm to 5pm. The seminars will include a coffee break. Attendance to the IYL seminars and coffee break is free of charge, but will require a separate registration (see the link to the IYL-2015 Seminars in the left menu). – Space Agencies Workshops on May 15th: INFN-LNF will ...

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## Top mass: challenges in definition and determination

Aim of the workshop: The top-quark mass definition and determination is a major subject of debate in both theoretical and experimental communities. Different strategies to relate the measured and theoretical quantities have been envisaged. The aim of this  3-day meeting is to convene experts on this topic to stimulate an informal discussion on different aspects of the issue. We plan to have only three or four talks each day, and plenty of time to discuss  the connection between the experimentally reconstructed top mass relying on Monte Carlo generators and different theoretical mass definitions, including the most advanced strategies. Implications of the top-mass determination for physics beyond the standard model will be also covered. The general approach and format will be pedagogical, the audience ranging from top-quark physics experts to graduate students, and should favour extended discussion among participants. Confirmed Speakers:   Spyridon Argyropoulos        (DESY, Hamburg) Vincenzo Branchina            (Catania U. & INFN) Roberto Chierici                        (CNRS & IPNL, Lyon) Marina Cobal                             (Udine U. & INFN) Roberto Franceschini          (CERN, Geneva) Andrè Hoang                           (Vienna U.) Sandra Leone                     (INFN Pisa) Fabio Maltoni                     (Louvain U.) Sven-Olaf Moch                 (DESY, Hamburg) Michael Scherer                 (Heidelberg U.) Adrian Signer                     (PSI, Villigen)

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## Low Dimensional Lattice Spin Models: Magnetization Plateau, Thermal Entanglement & Partition Function Zeros

Quantum phase transitions play a key role in the understanding the phenomena of many-body systems, especially in anti-ferromagnetic magnetic plateaus. By means of variation mean-field-like treatment based on the Gibbs–Bogoliubov inequality, it is presented the frustrated magnetization plateau and thermal concurrence properties in spin-1/2 Ising–Heisenberg models on a triangulated Kagom´e lattice and a diamond chain. Using the transfer matrix method, an exact solution for the magnetization plateau and thermal entanglement of Ising-XYZ, Blume-Emery-Griffiths and Hubbard-Ising models on a diamond chain can be obtained. Partition function zeros of the spin-1/2 and spin-1 Ising-Heisenberg models on a diamond chain have been calculated using the transfer matrix method. The existence usual and triple Yang-Lee edge singularity exponents are shown.

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## Perspectives on Dark Photons and Light Dark Matter

I will present the theoretical motivations for dark photons, vector bosons arising from a new U(1) gauge symmetry that kinetically mix with the photon. Such particles appear in a number of extensions of the Standard Model and can also be motivated from a purely effective field theory perspective as they provide one of the few portals to a dark sector. Such states have also found motivation in their ability to help explain astrophysical and terrestrial anomalies, such as the discrepant anomalous magnetic moment of the muon, and may also mediate interactions to light dark matter.

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