Krasnoyarsk underground neutrino laboratory

1. Krasnoyarsk underground neutrino laboratory V.P. Martemiyanov for NEUTRINO GROUP of Kurchatov Institute

2. n Location of Krasnoyarsk neutrino laboratory Organization: RRC “Kurchatov Institute” Location: Krasnoyarsk region, Zheleznogorsk E-mail: vpmar@dnuc.polyn.kiae.su Krasnoyarsk city is placed on the Yenisei river in vicinity of ancient mountains Sayani practically at the center of Russia

3. ZHELEZNOGORSK town Zheleznogorsk is situated at a distance of about 70 km from Krasnoyarsk on the bank оf Yenisei river. Town is disposed in vicinity of the Siberian taiga, which has а lot of birds and animals. There is а beautiful large lake in the center of the town. Picturesque hills surround the town center. А musicale theatre, hotel, rest home, restaurants, а lot of shops are in Zheleznogorsk. The weather is comfortable, the quantity of sunny days is the same as in Sochi. Winter is cold but not so much compared with Moscow, air is dry. The summer and autumn are warmer and sunnier than in Moscow. Every day one can take the flight from Moscow to Krasnoyarsk. Big comfortable airplane airbus IL86 in 4.5 hours will put you fromMoscow to Krasnoyarsk with good service of KrasAir Company. А special minivan during 2 hours will carry you from Krasnoyarsk airport Yemelianovo directly to the center of Zheleznogorsk.

4. Laboratory Krasnoyarsk neutrino laboratory was build on the МСС underground territory (MINING & CHEMICAL COMBINE) 53, Lenin Str., Zheleznogorsk, Krasnoyarsk region, Russia, 660972 At present the underground laboratory consist of two experimental halls on the 20 and 35 m distances from reactor core. The laboratory and the reactorboth are placed inside the rock (2700 kg/m3) and the passive shielding from cosmic muons corresponds to 600 m.w.е. The muon flux is suppressed by factor of 1000. The period “Reactor-ON“ is equal to approximately 50days, and therefore one can measure the background each two months, but not through 1-1.5 year as usual on power atomic station. Personnel: 10-12 specialists from RRC KI (mission position) Scientific users from St.-Petersburg Nuclear Physics Institute

5. Underground view The underground street The electro train station in the rock

7. Status of neutrino experiments at Krasnoyarsk • "DEUTERON" • Weak constants for charged and neutral currents Neutrino oscillations into the sterile state • Status: Finished 2001 • NESSI-2 • Search for neutrino magnetic moment • Status: In progress • Kr2Det • Search for neutrino oscillations (Ue3) by two-detectors method • Status: R&D • The specific conditions at Krasnoyarsk: • The underground location, • The antineutrino spectrum is almost pure 235U (difference < 1%), • Reactor stops each 50 days and therefore one can measure the background.

8. Deuteron (NC)ne+ d  p + n +ne’En > 2.23 MeV (CC)ne+ d  n + n +e+En > 4.03 MeV (CC)ne+ p  n + e+En > 1.80 MeV CCsd = (3.270.30)10-44 cm2/fission235U NCsd = (1.120.07)10-44 cm2/fission235U CCsp = (6.390.19)10-44 cm2/fission235U

9. NESSI, detector scheme ne+ e  e’ +ne’ Plastic scintiilator shielding

10. NESSIdetector’s photo Si detector matrix of one layer during the detector construction Si(Li) – multidetector, full mass is 80 kg 604 Si moduls and 1 - Ge (HiPu) Threshold: 50-100 keV NESSI detector - outer view

11. Background evolution Background in Ge detector without Cu shielding Background in Ge detector with Cu shielding N/(kg day) Background after the Cu shielding cleaning Moscow-Heidelberg experiment at Gran Sasso Weak neutrino-electron scattering effect in NESSI at Krasnoyarsk m =10-10mB E, keV m =510-11mB Background now is 32000/day, In Gran Sasso experiment – 1600/day

12. Some remarks about the realization Kr2Det experiment. -Reactor operation is free for collaboration -Reactor off (7-9 days) in every 50 days (16%) -There is next underground infrastructure: two lab. hall on the distances 110 m and ~1000 m from reactor (far hall may be on rent condition-) A line of electricity, air ventilation system, fair safety system railways to both halls -MCC (mining&chemical combine) may carry out construction of the detector vessel, passive shield and other engineering jobs within 3-4 years. -Kr2Det experiment is supported by local MCC authorities, RRC “Kurchatov Institute”. It is discussing the participation JINR (Dubna), PNPhI (St-Petersburg). -Special AGREEMENT between Ministry of Atomic Energy and foreign scientific centers should be conclude. ZHELEZNOGOSK CONDITIONS FOR LIVING -One can live in guesthouse, at a hotel, on a flat. -No problems with phones, bank accounts, food, rent car. -High level personal safety (closed city) -MCC is ready to give a office room in city with tel. and internet connection. -minivan to Krasnoyarsk airport (2 hours), plane to Moscow (4,5 hours). -the weather is comfortable, air is dry, many of sunny days. Kurchatov Institute and MCC may try to organize collaboration meeting in Zheleznogorsk on August or later this year.

13. View of the National park - Krasnoyarsk rock pillars

14. Who can guess what is the place on the picture?