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We present a status of the Baikal-GVD Project. The objective of this project is a construction of a km3-scale neutrino telescope in the Lake Baikal. As an important milestone, the first GVD engineering array has been deployed and ran in April, 2011. Application of a completely new technology gave us an opportunity to study all the basic elements of the future full detector and to finalize the GVD technical design. We discuss the configuration and the design of the engineering array as well as data performance with the preliminary results.

The NT1000 deep-water neutrino telescope with an effective volume of ∼2 km3 is currently being developed at Lake Baikal by the BAIKAL collaboration. The telescope will be composed of functionally independent setups—clusters of strings of optical modules based on photomultiplier tubes (with eight strings in each cluster). Since 2011, field tests of the basic elements and systems of the future telescope included in autonomous measuring complexes—prototypes of the NT1000 cluster—have been performed at Lake Baikal. The basic elements and the layout of one of the currently considered versions of the acoustic positioning system for the NT1000 telescope are described, and results of tests of the system prototype included as a component in the experimental cluster of the year 2012 are presented.

Baikal-GVD is a cubic-kilometer scale neutrino telescope, which is currently under construction in Lake Baikal. GVD will consist of an array of optical modules arranged in clusters of strings. The first GVD-cluster has been deployed and put in operation in April 2015. We describe equipment and methods for the calibration of the first GVD-cluster and discuss the accuracy of the calibration procedures.

The future next-generation neutrino telescope Baikal-GVD will be a km3-scale array aimed at the detection of astrophysical neutrino fluxes. It will have modular structure and consist of functionally independent sub-arrays - clusters of strings of optical modules. The prototyping phase of the project has been concluded in 2015 with the deployment of the first cluster of Baikal-GVD in Lake Baikal. We discuss the current status and perspectives of the Baikal-GVD project.

The operation of large underwater neutrino telescopes requires the precise knowledge of the water parameters governing light absorption and scattering, as well as a continuous monitoring of these parameters. For this purpose, a stationary underwater device, ASP-15, has been developed by the Baikal collaboration. We describe the basic assumptions and formulae behind ASP-15, the methods how absorption length, scattering length and phase functions are determined, the design of the device, and give some results obtained over many years of operation in conjuction with the Baikal telescope NT200.

The currently running NT200 and NT200+ Baikal neutrino telescopes and the prospects for development of the Baikal Neutrino Project are briefly descr⇊ed. Preliminary results of the search for neutrino events correlated with cosmological gamma-ray bursts at the NT200 are presented. The feasibility of developing a method for acoustic detection of ultrahigh-energy neutrinos in the Baikal Neutrino Project is discussed. The calculation results for the energy spectrum and zenith-angle distributions of atmospheric neutrinos in the energy range from 10 to 107 GeV obtained within various high-energy hadron-nucleus interaction models are presented.

The first stage Baikal Neutrino Telescope NT200 has been operating since 1998 and was upgraded to the 10 Mton detector NT200+ in 2005. The preparation towards a development of a km 3 -scale detector in Lake Baikal is currently a central activity point. As an important milestone a km 3 -prototype Cherenkov string, based on completely new technology, was installed in 2008 and has been successfully operating together with NT200+. It was upgraded in April 2009. Also, we review the status of high-energy acoustic neutrino detection activities in Lake Baikal.

The status of neutrino experiments in connection with the fundamental problem of searches for a signal from dark matter is discussed. Limits on the magnitude of the effect of dark-matter-particle annihilation in the Sun that were obtained with neutrino telescopes are presented. In particular, the first results from the NT-200 Baikal Deep Underwater Neutrino Telescope are described.

We review the status of the Lake Baikal Neutrino Experiment. The Neutrino Telescope NT200 has been operating since 1998 and has been upgraded to the 10 Mton detector NT200+ in 2005. We present selected astroparticle physics results from long-term operation of NT200. Also discussed are activities towards acoustic detection of UHE-energy neutrinos, and results of associated science activities. Preparation towards a km3-scale (Gigaton volume) detector in Lake Baikal is currently a central activity. As an important milestone, a km3-prototype string, based on completely new technology, has been installed and is operating together with NT200+ since April, 2008., Comment: 8 pages, 12 figures; presented at VLVNT08 (Very Large Volume Neutrino Telescope) Workshop, Toulon, France, April, 2008; to appear in NIM-A

Convenient synthesis of new methacryloyloxy-substituted phthalocyanines for polymerization reactions, i.e. copper(II) 2,9,16,23-tetra(methacryloxyethoxycarbonyl)phthalocyanine and copper 2,9,16-tris(tert-butyl)-23-(methacryloxyethoxycarbonyl)phthalocyanine, consisting of just a few steps, has been developed. The copolymerization with a dimethacrylate derivative was investigated. The substituted phthalocyanines are interesting materials for ophthalmosurgery in ophthalmology (contact vision correction of eye lenses).

The results of steady-state and time-resolved absorption and fluorescence experiments as well as quantum mechanical density functional theory (DFT) calculations of metal-free and Zn(II) mononuclear and dinuclear (sharing a common benzene ring) phthalocyanines are presented. A detailed comparison between measured and calculated absorption spectra of all compounds is done, showing a good agreement between theory and experiment. The NH tautomerization for phthalocyanines with an extended pi-electron system was shown for the first time at room temperature. The photophysical properties of all possible NH tautomers of metal-free dinuclear Pc have been fully characterized. In the first tautomer, Pc(parallel), both pairs of hydrogen atoms are parallel to the connection line of two Pc units. The maximum of the lowest-energy Q absorption band, lambda abs, in Pc(parallel) is located at 832 nm, whereas the spectral position of the fluorescence maximum lies at lambdafl=837 nm. The second NH tautomer, Pc(perpendicular) (lambdaabs=853 nm, lambdafl=860 nm), presents the two pairs of hydrogen atoms perpendicularly orientated to the covalent axis, and the third one, Pc(mix) (lambdaabs=864 nm, lambdafl=872 nm), contributing in a minor extend to the absorption and fluorescence spectra of the metal-free dinuclear phthalocyanine, has one perpendicular and one parallel pair of hydrogen atoms. Obviously, only one configuration exists in the case of the Zn(II)-containing dinuclear phthalocyanine (lambdaabs=845 nm, lambdafl=852 nm).

This paper presents a numerically efficient simulation method and its implementation based on spline interpolation technique for solving waveguide problems of arbitrary cross sections. In this work, analytical regularization method is used as the key approach.

The reactivity of phthalonitrile, tetrafluorophthalonitrile and 4,5-dibutoxyphthalonitrile with unmodified surfaces of ZnO and SiO 2 and with the modified systems SiO 2/ Cp 2 Co , ZnO / Cp 2 Co , SiO 2/ Zn ( AcAc )2 prepared by deposition of cobaltocene ( Cp 2 Co ) and zinc acetylacetonate Zn ( AcAc )2, was studied ("in-situ-synthesis") in processes of phthalocyanine coatings. The formation of structural uniform phthalocyanines on carriers were established by UV-vis and mass spectra. The compounds were used then to compare their catalytic and photocatalytic activities in the oxidation of sulfide as a test reaction.

Metal phthalocyanines can be very efficient as catalysts and photocatalysts in oxidation reactions using molecular oxygen as oxidant. Different types of soluble low molecular weight or oligomeric and insoluble heterogeneous catalysts and photocatalysts were developed. The heterogeneous metal phthalocyanines exist either impregnated on SiO 2, Al 2 O 3, charcoal and TiO 2 or covalently and coordinatively bound on SiO 2 and organic polymers or ionically bound on an organic ion exchanger. The catalytic oxidations of toxic sulfide and thiol derivative are studied. In addition, toxic phenols were employed as substrates for the photooxidation. Heterogeneous catalysts can exhibit higher activities then low molecular weight phthalocyanines. These systems exhibit a good stability for re-use. Photooxidations are more efficient than oxidations. A Si(IV) phthalocyanine derivative on a polymer ion exchanger is most active and stable. Also some examples for photooxidations in the direction of photochemical synthesis are given.

Polymeric phthalocyanines are prepared by polycyclotetramerization of tetracarbonitriles and electropolymerization of amino- or pyrrole-substituted phthalocyanines. The conjugated polymers are characterized by a long wavelength absorption and a high electrical conductivity.

We report theoretical and experimental results of on-going feasibility studies to detect cosmic neutrinos acoustically in Lake Baikal. In order to examine ambient noise conditions and to develop re- spective pulse detection techniques a prototype device was created. The device is operating at a depth of 150 m at the site of the Baikal Neutrino Telescope and is capable to detect and classify acoustic signals with different shapes, as well as signals from neutrino- induced showers.

Based on low molecular and macromolecular phthalocyanines as light absorbing compounds different light driven reactions are shortly discussed. These processes include under irradiation with visible light energy transfer in photooxidation reactions and electron transfer in photosensibilisation cells or photovoltaic cells. Catalytic oxidation reactions are also mentioned to compare the different mechanisms of dark and light oxidations.

The status of the Baikal neutrino experiment is briefly reviewed and the results of the search for the natural flux of high-energy neutrinos are reported.

Macromolecule metal complexes (MMCs)-the combination between a macromolecule, a metal chelate/complex/ion or cluster - are dominating factors for different functions in living systems, and are becoming more and more important in different sciences and applications as artifical synthesized systems.

We present updated results of the Baksan Underground Scintillator Telescope in search for a signal from dark matter particles annihilating in the center of the Sun. Based on the performance of the Baksan telescope measuring upward through-going muons with energy larger 1 GeV, we confirm the absence of observable excess in arrival directions towards the Sun relatively the expectations from neutrinos of atmospheric origin for 24.12 years of live time. We conclude that the 90% C.L. upper limits on elastic scattering cross sections of dark matter WIMP (Weakly Interactive Massive Particle) off proton are comparable with correspondent limits of other operating neutrino telescopes. The best value of the limit is $3 \times 10^{-4}$ picobarn in spin-dependent (SD) interaction of WIMP on proton for mass range about $100\div200$ GeV.

We present a new dataset analysis of the neutrino experiment at the Baksan Underground Scintillator Telescope with muon energy threshold about 1 GeV for the longest exposure time toward the Sun. In search for a signal from self-annihilations of dark matter particles in the center of the Sun we use an updated sample of upward through-going muons for 24.12 years of live time. No observable excess has been found in measured muons relative to expected background from neutrinos of atmospheric origin. We present an improved data analysis procedure and describe it in detail. We set the 90\% C.L. new upper limits on expected neutrino and muon fluxes from dark matter annihilations in the Sun, on the corresponding annihilation rates and cross sections of their elastic scattering off proton., Comment: 25 pages, 12 figures, analysis improved, discussion of systematic uncertainties added, references and two new figures added, modest changes in upper limits, conclusions unchanged. Version to appear in JCAP

We report on the current state of the Baikal acoustic neutrino detection project. The new results of pulse simulation are presented. The Askarian approach was exploited to calculate the acoustic pulses produced by ultra-high-energy (UHE) particles. Preliminary results of the telescope effective volume estimation are presented. It is described how new Acoustic Sensor Modules are put into operation.

The results of a search for high energy neutrino signals from hypothetical supersymmetric dark matter based on the data collected with the Baksan Underground Scintillator Telescope are presented. The upward going muon statistics collected during 15 years of operation is used. The limits on the neutrino flux from neutralino annihilations in the Sun and Earth are given for a wide range of model parameters. The region of these parameters, excluded by Baksan data at the 90% c.l. is obtained.

The neutrino telescope Baikal-GVD in Lake Baikal will be a research infrastructure aimed mainly at studying astrophysical neutrino fluxes. The telescope will consist of clusters of strings – functionally independent sub-arrays. The deployment of the first demonstration cluster has been started in April 2013. In 2014 the deployment of the second stage of the demonstration cluster has been performed. We describe the configuration and design of the first GVD cluster and review the current status of cluster deployment in Lake Baikal.

In April 2015, the first cluster of Baikal-GVD was deployed in Lake Baikal and put into operation. It comprises eight strings. Each string consists of 24 optical modules. An optical module is a detection element of Baikal-GVD; it includes a Hamamatsu R7081-100 photomultiplier tube with a high quantum sensitivity. We describe the design of the optical module, the front-end electronics, and the laboratory characterization and calibration.

The first stage of the GVD-cluster composed of five strings was deployed in April 2014. Each string consists of two sections with 12 optical modules per section. A section is the basic detection unit of the Baikal neutrino telescope. We will describe the section design, review its basic elements – optical modules, FADC readout units, slow control and calibration systems, and present selected results for section in-situ tests in Lake Baikal.

New efficient approach for simulation of waveguides and cylindrical resonators of arbitrary profile is suggested. Numerical investigations for the abilities of algorithm and comparison with known results show high efficiency and accuracy of the method.

The construction of a km 3 -scale neutrino telescope – the Gigaton Volume Detector (GVD) in Lake Baikal – is the central goal of the Baikal collaboration. During the R&D phase of the GVD project in 2008–2010 years the basic elements of GVD – new optical modules, FADC readout units, underwater communications and trigger systems – have been developed, produced and tested in situ by long-term operating prototype strings in Lake Baikal. The prototyping phase of the GVD project has been started in April 2011 with the installation of a three string array (prototype cluster) which comprises all basic elements and systems of the GVD-telescope in Lake Baikal. We describe configuration and technical design of the GVD, present selected results obtained during 2008–2010 with prototype strings, and describe configuration and design of the 2011 prototype cluster.

We report the present status and perspectives of the feasibility study to detect cosmic neutrinos acoustically in the Lake Baikal. The results of background studies are presented. It was shown that most of the detected neutrino-like pulses come from the lake surface. This fact has been used in the project of an acoustic prototype detector that consists of compact Acoustic Sensor Modules with 4-channel antennas each, arranged above the Baikal Neutrino Telescope at shallow depths and “listening” the deep-water layers of the lake.

Mathematically strong and numerically efficient approach for the simulation of the waveguides and the cylindrical resonators of arbitrary profile in the case of H-(TE-) polarized waves is suggested. The approach is based on the new implementation of the Analytical Regularization Method. Special attention is drawn to the infinitely smooth profiles, which gives a possibility to achieve a super-algebraic (faster than any algebraic) rate of the methods' convergence.

The objective of the Baikal Project is the creation of a kilometer-scale high-energy neutrino observatory: the Gigaton Volume Detector (GVD) in Lake Baikal. Basic elements of the GVD – new optical modules, FADC readout units, and underwater communication systems – were investigated and tested in Lake Baikal with prototype strings in 2008–2010. We describe the results of prototype strings operation and review the preliminary design and expected sensitivity of the GVD telescope.

A project of the NT1000 deep-water neutrino telescope with an effective volume of ∼1 km3 is currently being developed by the BAIKAL collaboration. The telescope will be located in Lake Baikal in close vicinity of the NT200+ detector, which is currently in operation. The telescope will be composed of 12 clusters with 8 similar strings of optical modules in each (each string has two sections of the NT1000 optical modules). The section of the NT1000 optical modules has been developed using higher-efficiency photomultiplier tubes and state-of-the-art electronics. The field tests of the experimental string consisting of two sections with six optical modules in each have been performed. The results of these investigations are used in the project of the NT1000 neutrino telescope and in the hydrological study of Lake Baikal.

We review the status of the Lake Baikal Neutrino Experiment. Preparation towards a km3-scale Gigaton Volume Detector (GVD) in Lake Baikal is currently a central activity. As an important milestone, a km3-prototype string comprising of 12 optical modules and based on a completely new technology, has been installed and was put in operation together with NT200+ in April, 2009. We also present recent results from the long-term operation of NT200, including an improved limit on the diffuse astrophysical neutrino flux.

Mathematically strong and numerically efficient approach for simulation of waveguides and cylindrical resonators of arbitrary profile in the case of H-(TE-) polarized waves is suggested. The approach is based on new implementation of Analytical Regularization Method. Special attention paid to methods of the profiles infinitely smoothing, which gives a possibility to achieve a super-algebraic (faster any algebraic) rate of the method convergence.

The analytical regularization method is applied to the problem o f 3D TM-ϕ wave diffraction by perfectly conductive axially symmetrical a nnular surfaces consisting a set of closed and unclosed ones. The electromagnetic boundary value problem is reduced to t he infinite algebraic system of the second kind which in principal can be solved with any predetermined accuracy by means of truncation procedure. Numerical results, including condition number and field's space distribution for obstacles will be presented.

Mirror antennae formed by curvilinear perfectly conducting screens are classic objects of theoretical and experimental investigations, which already resulted in numerous scientific and engineering publications. The most typical full wave models of such antennae are based on mathematical approach of infinitely thin and perfectly conductive screens. In many cases screen is formed by a surface in 3D space. At the same time, cylindrical antennae and their models as homogenous and infinite in longitudinal direction cylindrical surfaces are also having their place in modern radio science. Our presentation is focused on such cylindrical antennae models both infinitely thin and of finite thickness with various shapes and screen thickness. Namely, we try to estimate how finite thickness influences the antenna characteristics and, in particular, estimate validity of the models based on infinitely thin screens relatively to different physical purposes of modeling. We have chosen Analytical Regularization Method (ARM) as a tool for our investigation. In publications [1, 2] aiming the similar investigation, where Semi-Inversion Procedure (SIP) [3] was used, it was claimed that ARM was used. This mistaken claim occurred due to mismatching of the standard terminology [4, 5, 6 and references therein]. Using ARM instead of SIP gives possibility to obtain algorithms of essentially better quality than those of [1, 2]. Moreover, we implement ARM in such a way that it is super-algebraically (faster than any negative power of the reduced algebraic system) convergent.

We review the status of the Lake Baikal Neutrino Experiment. Preparation towards a km3-scale Gigaton Volume Detector (GVD) in Lake Baikal is currently a central activity. As an important milestone, a km3-prototype string comprising 6 optical modules and based on a completely new technology, has been installed and was put into operation together with NT200+ in April, 2008. An upgraded version of the prototype string, which comprises 12 optical modules, was put into operation in April 2009. We also present new results from the long-term operation of NT200, including an improved limit on the diffuse astrophysical neutrino flux.

We investigate neutralino dark matter in the framework of NMSSM performing a scan over its parameter space and calculating neutralino capture and annihilation rates in the Sun. We discuss the prospects of searches for neutralino dark matter in neutrino experiments depending on neutralino content and its main annihilation channel. We recalculate the upper limits on neutralino-proton elastic cross sections directly from neutrino telescopes upper bounds on annihilation rates in the Sun. This procedure has advantages as compared with corresponding recalcalations from the limits on muon flux, namely, it is independent on details of the experiment and the recalculation coefficients are universal for any kind of WIMP dark matter models. We derive 90% c.l. upper limits on neutralino-proton cross sections from the results of the Baksan Underground Scintillator Telescope., Comment: 28 pages, 16 figures, accepted for publication in JCAP, references added

The detection of upward through-going muons with The Baksan Underground Scintillator Telescope has been ongoing for almost two decades. In this note we report: (i) Updated results of the observation of upward through-going muons carried out with the Baksan Underground Telescope since December of 1978; (ii) The discussion of systematic uncertainties; (iii) The discussion of possible background sources.

Mathematically strong and efficient approach for simulation of resonators and waveguides of arbitrary profile is suggested. The approach is based on new implementation of Analytical Regularization Method. Numerical results of E-polarized wave diffraction by waveguide resonant structures demonstrate the method efficiency and reliability.

A prototype string for the future km3-scale Baikal neutrino telescope has been deployed in April, 2008 and is fully integrated into the NT200+ telescope. All basic string elements - optical modules (with 12"/13" hemispherical photomultipliers), 200MHz FADC readout and calibration system - have been redesigned following experience with NT200+. First results of in-situ operation of this prototype string are presented., Comment: 8 pages, 15 figures; presented at VLVNT08 (Very Large Volume Neutrino Telescope) Workshop, Toulon, France, April, 2008; to appear in NIM-A

Metal-free mononuclear, dinuclear and trinuclear phthalocyanines were prepared by a mixed cyclotetramerisation of a 1,2,4,5-tetracyanobenzene derivative and 4,5-bis(2,6-dimethylphenoxy)phthalonitrile. For the first time, a pi-electron-conjugated trinuclear phthalocyanine was synthesised with phthalocyanine units connected by common annulated benzene rings. The Q band of the trinuclear compound in solution occurs at lambda = 944 nm whereas those of the dinuclear and mononuclear compounds are at lambda = 853/830 and 701/664 nm, respectively. Fluorescence quantum yields, fluorescence lifetimes and singlet-oxygen quantum yields of the compounds were determined.

The development of the NT1000 km3 neutrino telescope at Lake Baikal has been the main goal of the BAIKAL collaboration since 2006. This work presents selected results obtained in the course of developing and testing key elements and systems of the future detector.

I discuss here the status of tools for the indirect methods of looking for a hypothetical neutralino signal using Neutrino Telescopes.

We present a current status of the Baikal-GVD Project. The objective of this project is a construction of a km3-scale neutrino telescope in the Baikal lake. Set of prototype arrays which were installed and operated during 2009-2011 in Lake Baikal allowed to study all basic elements of the future full detector and to finalize the GVD technical design. We discuss the configuration and the design of the engineering arrays as well as DAQ performance and the preliminary results.

The experimental results obtained at the Baksan underground scintillation telescope are briefly reviewed. The neutrino flux from galactic sources has been studied, and an upper limit has been obtained on it. An upper limit has been placed on the flux of heavy magnetic monopoles by searching for slow ionizing particles. The signal from the neutrino momentum in supernova birth has been detected. A limit on proton decay has been obtained. By recording muons from extensive air showers, it has been shown that their chemical composition does not vary up to 5×10 15 eV .