T. Gress

The BAIKAL neutrino experiment—Physics results and perspectives

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.

The prototyping/early construction phase of the BAIKAL-GVD project

Abstract The prototyping phase of the BAIKAL-GVD project has been started in April 2011 with the deployment of a three string engineering array which comprises all basic elements and systems of the Gigaton Volume Detector (GVD) in Lake Baikal. In April 2012 the version of engineering array which comprises the first full-scale string of the GVD demonstration cluster had been deployed and operated during 2012. The first stage of the GVD-cluster which consists of three strings was deployed in April 2013. We review the prototyping phase of the BAIKAL-GVD project and describe the configuration and design of the 2013 engineering array.

Search for Neutrinos from Gamma-Ray Bursts with the Baikal Neutrino Telescope NT200

We present the results of our search for neutrino events coinciding in time and direction with gamma-ray bursts (GRBs) with the Baikal underwater neutrino telescope NT200. No events confirming a neutrino accompaniment of GRBs have been detected. Model-independent limits (Greens function) on the neutrino flux from GRBs have been obtained. For the Waxman-Bahcall neutrino spectrum, the limit on the neutrino flux from a GRB has been found to be Eν2Φν ⩽ 1.1 × 10−6 GeV cm−2 s−1 sr−1.

Sensitivity of the Baikal-GVD neutrino telescope to neutrino emission toward the center of the galactic dark matter halo

We analyze sensitivity of the gigaton volume telescope Baikal-GVD for detection of neutrino signal from dark matter annihilations or decays in the Galactic Center. Expected bounds on dark matter annihilation cross section and its lifetime are found for several annihilation/decay channels.

An experimental string of the NT1000 Baikal neutrino 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.

The study of primary cosmic rays energy spectrum and mass composition in the energy range 0.5 – 50 PeV with TUNKA Eas Cherenkov array

The Tunka-13 EAS array has operated two winter seasons since 1996 until 1998 years. It consists of 13 Cherenkov light detectors based upon the QUASAR-370 phototubes. The array covers the area 240 x240 m2 and measures the primary energy, derived from Cherenkov light flux, and individual lateral distribution functions (LDF). Good energy and angular resolution of the array permits to study the irregularities in energy spectrum following the classic “knee”.

Status and recent results of the BAIKAL-GVD project

The Prototyping phase of the BAIKAL-GVD project has been started in April 2011 with the deployment of first autonomous engineering array which comprises all basic elements and systems of the Gigaton Volume Detector (GVD) in Lake Baikal. The prototyping phase will be concluded with deployment of the GVD demonstration cluster “DUBNA” in 2015, which will comprise 192 light sensors arranged at 8 strings. The first stage of the GVD demonstration cluster which consists of three strings was deployed in April 2013 and successfully operated up to February 2014. We review the prototyping phase of the BAIKAL-GVD project and describe the configuration and design of the 2013 engineering array.

THE BAIKAL NEUTRINO TELESCOPE — RESULTS AND PLANS

New results from the Baikal neutrino telescope NT200, based on the first 5 years of operation (1998–2003), are presented. We derive an all-flavor limit on the diffuse flux of astrophysical neutrinos between 20 TeV and 50 PeV, extract an enlarged sample of high energy muon neutrino events, and obtain limits on the flux of high energy atmospheric muons. In 2005, the upgraded telescope NT200+ will be commissioned: 3 additional distant strings with only 12 photo-multipliers each will rise the effective volume to 20 Mton at 10 PeV for this largest running neutrino telescope in the Northern hemisphere.

BAIKAL experiment: status report

We review the present status of the Baikal Neutrino Project and present the results obtained with the deep underwater neutrino telescope NT-200.We review the present status of the Baikal Neutrino Project and present the results obtained with the deep underwater neutrino telescope NT-200

Lake Baikal Neutrino Experiment: Selected Results

We review the present status of the Lake Baikal neutrino experiment and present selected physics results obtained during the consecutive stages of the stepwise upgrade of the detector: from NT-36 to NT-96. The results cover atmospheric muons, neutrino events, neutrinos of very high energy, searches for neutrino events from WIMP annihilation, searches for magnetic monopoles, and environmental studies. We also describe an air Cherenkov array developed for studying the angular resolution of NT-200.