Plan for future GaAs samples for TestBeam measurements JINR DLNP group (presented Z. Krumshteyn) JINR DLNP group (presented Z. Krumshteyn) FCAL Collaboration Meeting, June , 2009, Zeuthen

Batch N carriers n/cm -3 Nplates Darmstadt Beam expired KIAE SI exp. 1 ( )(1-1.5)* ,10,11,12 9 (pad1), 11(pad4) 10(pad1) 2 (AG )(5-6)* ,6,7,8 5(pad4), 7(pad3)? 8(pad1) 3 ( )(1-3)* ,2,31,41 2(pad1), 31(pad4) 41(pad1) 4 (AP )(2-5.5)* ,14,15,16 p-ν-n- structure* bonus(2-3)* , 4, 1-1,2-1 Table 1. GaAs samples 2008 FCAL Collaboration Meeting, June , 2009, Zeuthen

Initial n-GaAsFabrication method №1, n  (1 -1.5)*10 17 см -3,Te Diffusion of Cr under temperatureT2 №2, n  (5 - 6)*10 16 см -3, Te Diffusion of Cr under temperature Tm №3, n  (1 - 3)*10 16 см -3, Sn Diffusion of Cr under temperature T1 №4, n  (2 - 5)*10 16 см -3, Te p-ν-n- structure* Notice T1  Tm<T2. * - presence in the detector n- type low-resistance domain, all other detectors №1, 2, 3 had structure m-i-m: metal- insulator (high-resistance GaAs) –metal. Table 2. GaAs samples 2008(Fabrication method) FCAL Collaboration Meeting, June , 2009, Zeuthen

Table 3. experimental GaAs detectors 2009 FCAL Collaboration Meeting, June , 2009, Zeuthen Initial n-GaAs, n  (2-5)*10 16 см -3 Fabrication methodNumber GaAs, doping Sn Diffusion of Cr under temperature T1 2(?) Diffusion of Cr under temperature T2 2(?) GaAs, doping Te Diffusion of Cr under temperature T1 2(?) Diffusion of Cr under temperature T2 2(?) Total8(?) Notice T1  T2. On the basis study of rad.hardness of batch №3 (2008). Within initial concentration n-GaAs, (2-5)*10 16 см -3, it will be investigate radiation hardness vs impurity (Sn, Te) and temperature (T1, T2)

µm 300 µm Shape of GaAs sample 2008Shape of GaAs sample 2009 FCAL Collaboration Meeting, June , 2009, Zeuthen

In Joint Institute for Nuclear Research (JINR), Dubna the project of new Intense REsonance Neutron source (IREN) is under construction now. The IREN will be used as a neutron source of new generation for research of the broad spectrum of problems in fundamental and applied nuclear physics. The IREN source is intended for nuclear physic investigations by a time-of-flight on a place and in a building of LUE-40 + IBR-30 installation removed from operation, thus the existing infrastructure of eight neutron beams with fly paths from 10 up to 750 m, an experimental hall and measuring pavilions is completely used. The IREN source exploiting a booster principle should provide a fast multiplication of initial neutrons produced by an electron beam from a linear accelerator in electron-neutron converter. So its design has to ensure as short as possible time t <10 ns for one act of neutron multiplication into a subcritical blanket, the total duration of a fast neutron pulse about 400 ns with the repetition rate 150 Hz, and a neutron yield at a level n/s. The project will be implemented in two stages. At the first stage the linear accelerator and nonmultiplying target will be constructed. FCAL Collaboration Meeting, June , 2009, Zeuthen

COMPARISON OF THE IREN SOURCE WITH OTHER NEUTRON SOURCES AIMED FOR NUCLEAR PHYSICS Neutron source(Laboratory), n/s C, 10 7 t, ns dt (at 100 eV), ns FAKEL (IAE, Russia) ORELA (ORNL, USA) GELINA ( IRMM, Belgium) LUE-40+IBR-30 (Dubna, put out of operation) LANSCE (LANL, USA) CERN PS TOF facility IREN (Dubna, project) t – duration of fast neutron burst ; dt – real duration of neutron pulse at E n = 100 eV after moderation of neutrons; С is define by relation φ(En)=C/ En*L2,were φ(En ) – neutron flux with energy Е n (eV) on the 1 cm 2 sample, located on the distance L meter from source, а - total yield of neutrons per second.

LINEAR ACCELERATOR The travelling wave electron linac LUE-200 was designed at the Budker Institute of Nuclear Physics (BINP), Novosibirsk Beam average power10 kW Electron energy200 MeV Pulse current<250ns Repetition rate150 Hz Number of accelerating sections2 IREN 1-st stage parameters Beam average power1.25kW Electron energy100 MeV Pulse current100ns Repetition rate50(150) Hz Peak current (A)2.5 A FCAL Collaboration Meeting, June , 2009, Zeuthen