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The Novosibirsk FEL facility has three FELs installed on the first, second, and fourth orbits of the multiturn energy recovery linac (ERL). The first FEL covers the 90–240 μm range of wavelengths at an average radiation power of 0.5 kW with a pulse repetition rate of 5.6 or 11.2 MHz and a peak power of 1 MW. The second FEL operates in the 40–80 μm range of wavelengths at an average radiation power of 0.5 kW with a pulse-repetition rate of 7.5 MHz and a peak power of around 1 MW. These two FELs are the world’s most powerful (in terms of average power) sources of coherent narrow-band (less than 1%) radiation in their wavelength ranges. The third FEL was commissioned in 2015 to cover the 5–20 μm range of wavelengths. The Novosibirsk ERL is the world’s first and only multiturn ERL. Its distinctive features include a normally-conductive 180 MHz accelerating system, a direct current (DC) electrostatic electron gun with a control grid and thermionic cathode, three operating modes of the magnetic system, and a compact (6 × 40 m) design. The Novosibirsk FEL facility has been in operation for users of terahertz radiation since 2004.

Novosibirsk FEL facility is based on the first in the world multi-turn energy recovery linac (ERL). It comprises three FELs (stages). FELs on the first and the second tracks were commissioned in 2004 and 2009 respectively and operate for users now. The third stage FEL is installed on the fourth track of the ERL. It includes three undulator sections and 40-meters-long optical cavity. The design tuning range of this FEL is from 5 to 20 microns and the design average power at bunch repetition rate 3.74 MHz is about 1 kW. Recent results of the third stage FEL commissioning are reported.

To improve the parameters of the second stage Novosibirsk free electron laser we plan to replace the existing electromagnetic undulator by permanent-magnet variable-period undulator (VPU). The VPUs have several advantages compared to conventional undulators, which include wider radiation wavelength tuning range and an option to increase the number of poles. Both these advantages will be realized in the new undulator under development in Budker INP. There are some technical problems, which have to be solved before this idea can be implemented in practice. To check the solution of these problems we designed and manufactured a small undulator prototype, which has just several periods. In this paper, the results of mechanical and magnetic measurements of this undulator prototype are presented and compared with simulations.

A hybrid wiggler for synchrotron radiation research program at the VEPP-4 was created in the Budker Institute of Nuclear Physics, Novosibirsk, Russia. The wiggler consists of ordinary poles with coils, which generate a spatially periodic magnetic field equal to 1.75 T. Also, permanent magnets are insertion between the poles for increasing magnet field up to 1.9 T. In this paper, we present the design, calculations, and magnetic measurements for the hybrid wiggler.

The National Synchrotron Light Source II is a third generation light source, which was constructed at Brookhaven National Laboratory. This project includes a highly-optimized 3 GeV electron storage ring, linac preinjector, and full-energy synchrotron injector. Budker Institute of Nuclear Physics built and delivered the booster for NSLS-II. The commissioning of the booster was successfully completed. This paper reviews fulfilled work by participants.

The high-power free electron laser (FEL) facility NovoFEL has been created at Budker INP. Its wavelength can be tuned over a wide range in terahertz and infrared spectrum regions. This FEL uses a multi-turn energy recovery linac with five straight sections as a source of electron beam. Three sections are used for three FELs which operate in different wavelength ranges (the first at 90-240 μm; the second at 37 – 80 μm; the third at 5 – 20 μm). The first and second FELs were commissioned in 2003 and 2009, respectively. They operate for users now. The third FEL is installed on the fourth accelerator track, which is the last one; the electron energy is maximal here. This FEL comprises three undulator sections and a 40-m optical cavity. The first lasing of this FEL was obtained in the summer of 2015. The radiation wavelength was 9 μm and the average power was about 100 W. Radiation of the third FEL was delivered to the user stations, and the first user shifts were performed recently. The results of the commissioning of the third FEL, the current status of the first and second FELs and future development prospects are presented.

VEPP-4 is a multipurpose storage ring facility at Budker Institute of Nuclear Physics (Novosibirsk, Russia) with several research programs including high energy physics in colliding beam mode, nuclear physics, synchrotron radiation, accelerator physics study, etc. The paper discusses VEPP-4 activities relating to generation and application of synchrotron radiation not only for SR user community but for beam diagnostics in storage ring as well.

A compact hybrid magnet wiggler is under development for the VEPP-4 SR research program. The wiggler allows increasing the photon flux two orders of magnitude at a beam energy of 4.5 GeV in the spectrum range of 60-100 keV. The magnet consists of conventional coils, which generate a magnetic field, and permanent magnet insertions, which concentrate the flux. This solution increases the field in the beam orbit up to 2.05 T. Here we present the design, magnetic calculations and analysis of the beam dynamics under the hybrid wiggler influence.

Novosibirsk free electron laser (FEL) facility contains three FELs operating in the wavelength range 8–240 micron at average power up to 0.5 kW and peak power about 1 MW. Radiation users works at 6 user stations performing biological, chemical, physical and medical research.

The article describes a model of permanent magnet wiggler (PMWM) to reduce the emittance of accelerator Petra III. The PMWM model is one wiggler period (the period λ =0.2 m; the distance between the poles is 0.024 m and the maximal magnitude of magnetic field B is 1.5 T). BINP SB RAS have developed and manufactured a system to measure magnetic moment of permanent magnets (PMs) with accuracy ⩽5×10 −4 with PMs ⩽0.09 m in size.

Three elliptical undulators HU256 (period 256 mm) of electromagnetic type were produced, tested and magnetically measured by the Budker Institute of Nuclear Physics (Russia) for Synchrotron SOLEIL (France). The undulators have a new design of a Bx and Bz closed structure for insertion vacuum chamber. The magnetic calculations of the individual dipoles and undulator structures were executed by means of Mermaid 3D Code. The expected magnetic parameters for all manufactured dipoles were fulfilled on basis of these model dependences from the mechanical characteristics (pole gap, yoke width, and coil position). The estimated 1st integral of all dipoles had been used in an optimal arrangement of the dipoles in undulators (sorting). Owing to the realized sorting, the 1st integral of the magnetic field and phase error of the assembled undulators had been decreased in comparison with the statistic estimations. The special Hall probes systems for the magnetic measurements of the undulators HU256 were designed and manufactured by the BINP. All three HU256 undulators were magnetically measured at the BINP and re-measured at the SOLEIL after transportation. The results of magnetic measurements and model estimates are compared and analyzed.

The article describes a prototype of the permanent magnet (PM) wiggler to reduce the emittance of the accelerator Petra III. The wiggle has the following parameters: the length is 4.04 m; the pole gap is 0.024 m and the maximal field is B=1.56 T; the wiggler has 20 periods with λ=0.2 m.

The first lasing near wavelength 140 μm was achieved in April 2003 on a high-power free electron laser (FEL) constructed at the Siberian Center for Photochemical Research. In this paper, we briefly describe the design of FEL driven by an accelerator–recuperator. Characteristics of the electron beam and terahertz laser radiation, obtained at the first experiments, are also presented in the paper.

In this paper, we present an attempt to improve the field quality in the pseudo-helical wigglers used in the OK-5 VUV FEL at Duke. One type of “imperfection” of a wiggler intrinsic for any magnetic system and affecting the dynamic aperture is non-linear focusing. We tried to find an approach to reduce affect of the wiggler on dynamic aperture. Another kind of imperfection of the field in the pseudo-helical wigglers are caused by asymmetry of design. In our case the asymmetry of the coils allows the presence of small average quadrupole and octupole fields. We used small asymmetric cuts in the poles to eliminate these terms. The magnetic field in the regular part of the wiggler was simulated with the use of 3D code “MERMAID”. All four wigglers have been fabricated and measured. Magnetic measurements show good agreement with the simulations.

A high-precision electromagnetic undulator has been developed for a compact FIR free-electron laser (FEL) driven by a magnetron-based microtron. Permanent magnets are placed between iron poles to compensate for the high-flux magnetic field generated by the main coils. The period of the undulator is 25 mm and the number of periods is 80. We can change the K-parameter from 1 to 1.6 (Bw ¼ 4:526:8 kG at a fixed gap of 5.6 mm) in order to cover the FEL wavelength range from 100 to 300mm at an electron energy of 6.5–4 MeV. The undulator has a modular structure of iron poles and a novel correction scheme of field distribution to improve significantly the accuracy of the field distribution. The r.m.s. deviation of the field distribution was improved from 0.2% to 0.05% with the correction method. The undulator shows considerable advantages in performance, compactness, cost effectiveness, and simplicity in manufacturing and construction. r 2002 Elsevier Science B.V. All rights reserved. PACS: 07.55.Db; 41.60.Cr

The OK-5/Duke storage ring free electron laser (FEL) project was started in 1998. Presently, the components of the OK-5 FEL and the new South straight section are in the final stage of manufacturing. This paper describes the design and the main features of the OK-5/Duke storage ring FEL. The basic concepts and main compromises made in the design process are presented. Plans for the OK-5 FEL commissioning are discussed.

In this paper, we present the design and parameters of electromagnetic wigglers with controllable polarization for the VUV OK-5/Duke storage ring FEL. The OK-5 FEL, the first distributed optical klystron, is comprised of four wigglers and three matching sections with individually controlled quadrupoles and bunchers. The geometry and the relative strength of horizontal and vertical fields determine the polarization of the radiation from the OK-5 wigglers. We compare the predicted and measured quality of the wiggler fields.

The KAERI compact far-infrared (FIR) free-electron laser (FEL) has been operated successfully in the wavelength range of 97–150 μm. It is the first demonstration of FEL lasing by using a magnetron-based classical microtron. We developed a high precision undulator consisting of 80 periods, with each period being 25 mm. The field strength of the undulator can be changed from 4.5 to 6.8 kG with an amplitude deviation of only 0.05% in r.m.s value. The kinetic energy of the electron beam is 6.5 MeV. The average current and pulse duration of the electron beam macropulses are 45 mA and 5.5 μs, respectively. The measured power of the FEL with the electron beam parameters was more than 50 W for a FIR macropulse having a duration of 4 μs. The spectral width of the FEL was measured to be 0.5% of the central wavelength. The FEL system, aside from the racks for the controlling units, is compact enough to be located inside an area of 3×4 m 2 .

A high-power infrared free electron laser is under construction in Novosibirsk. As the full-scale machine seems to be complicated and quite expensive, the project was divided into two stages so that the first-stage machine can be assembled and commissioned as soon as possible. Main features of the project and the current status are described.

The project "Dubna Electron Synchrotron" (DELSY) is aimed to construct a synchrotron radiation source of the 3d generation at the Joint Institute for Nuclear Research. The DELSY synchrotron radiation source will be constructed on the base of the accelerator facility of the Institute for Nuclear Physics and High Energy Physics (NIKHEF), Amsterdam, the Netherlands. This accelerator facility consists of a linear electron accelerator MEA (Medium Energy Accelerator) for the electron energy of 700 MeV and the electron storage ring AmPS (Amsterdam Pulse Stretcher) for the maximum electron energy of 900 MeV at the circulating beam current of 200 mA. The DELSY storage ring is supposed to be constructed with the use of the "Amsterdam Pulse Stretcher" (AmPS) [1] storage ring the focusing system of which will be essentially modified: the ring circumference will be approximately 1.5 times smaller, the electron energy will be increased up to 1.2 GeV and the focusing strength will be enhanced. These measures will allow obtaining the beam emittance at least ten times smaller which subsequently increases the synchrotron radiation brilliance by several orders of magnitude. The rigging of the DELSY ring with the insertion devices — the superconducting wiggler with the magnetic field of 10 T and the so-called "vacuum hybrid miniundulator" is the principle feature of the new synchrotron radiation source. Both devices developed by Budker INP, Novosibirsk, will allow to enrich the DELSY characteristics as the synchrotron radiation source expanding its radiation spectrum in the region of the hard X-rays and increasing its brilliance up to 3 ⋅10 18

In this paper, we report first lasing results in the near-UV and visible spectral ranges with the OK-4/Duke storage ring – the first storage ring FEL operating in the United States. The OK-4/Duke FEL was commissioned in November 1996 and demonstrated lasing in the 345–413 nm range with extracted power of 0.15 W. In addition to lasing, the OK-4/Duke FEL generated a nearly monochromatic (1% FWHM) γ-ray beams. In this paper, we describe initial performance of the OK-4/Duke storage ring FEL and γ-ray source in this demonstration experiment. We briefly discuss the present status of the project and its future user program.

An equipotential-bus electromagnetic undulator has been developed for a far infrared compact free-electron laser. It has 2 m length, 5.6 mm gap, and 12.5 mm period. The field distribution along the undulator is formed by 2.25 mm thick poles of low-carbon steel with 4 mm thick Nd–Fe–B permanent magnets between them. The amplitude of the magnetic field is up to 6 kG. The variation of current allows us to vary the field amplitude within 10% in a constant gap. For the distribution of the peak amplitude along the undulator we obtained random r.m.s. deviation less than 0.5% without further field correction or individual adjustment of each iron pole or magnet.

The Korean Atomic Energy Research Institute and the Budker INP developed a design and manufactured the main parts of a free electron laser with emission power of one watt in the infrared region of 25 to 30 microns including 10-cm microtron. After the commissioning of microtron, beamline and undulator electron beams were transmitted through the undulator and by using a special code microtron electron beam, performance parameters were measured and computed.

The method for measurement of the magnetic field of a system where the magnetic field integral is close to zero by the current strained wire method is described. This method is successfully applied to high accuracy compensation of a field in magnets required first and second integrals to be zero along a trajectory of an electron beam, such as strong field wigglers and shifters. Exact compensation of the integrals permits us to avoid orbit distortion which could appear after installation of such magnetic system on the storage ring. Experimental data of the presented method are in good agreement with a computer-designed model.

The paper describes the design, magnetic computations and measurements of the elliptical undulator HU256 for Synchrotron Soleil (France): the new technology for insertion vacuum chamber has permitted the design of a Bx & Bz dipole closed structure for an electromagnetic undulator. This magnetic design has been realized on the basis of the 2-D, 3-D modeling (Mermaid and RADIA codes), and dependence's of the magnetic field integrals from the main macroscopic parameters have been obtained. The undulator can work in standard and quasi-periodical modes. The single dipoles and the undulator HU256 were magnetically measured by a Hall probes system. The results of magnetic measurements and computations are compared and analyzed

The high power infrared free electron laser is under construction at the Novosibirsk Scientific Centre. The goal of this project is to provide a user facility for Siberian Centre of Photochemical Researches. The features of the installation and its status are described.

The construction of a dedicated SR source — the 2 GeV PLS — is being completed in Korea. The superconducting 3-pole wiggler (the wavelength shifter) with a 7.5 T maximum field at the central pole, which is to be installed at the PLS storage ring, was manufactured by the Budker Institute of Nuclear Physics (Novosibirsk) in cooperation with the PLS Laboratory (POSTECH, Pohang). The magnetic field at the side poles does not exceed 1.7 T in order to suppress the second source in the hard spectral region. The basic parameters of the wiggler and the radiation properties are given. Preliminary results of the wiggler testing in a special immersed cryostat are presented.

A 100 MeV eight-turn accelerator-recuperator intended to drive a high-power infrared free-electron laser (FEL) is currently under construction in Novosibirsk. The first stage of the machine includes a one-turn accelerator-recuperator that contains a full-scale RF system. It was commissioned successfully in June 2002.

To achieve high luminosity at the collision point of the Compact Linear Collider (CLIC) the normalized horizontal and vertical emittances of the electron and positron beams must be reduced to 500 nm and 4 nm before the beams enter the 1.5TeV linear accelerators. An effective way to accomplish ultra-low emittances with only small effects on the electron polarization is using damping rings operating at 2.86 GeV equipped with superconducting wiggler magnets. This paper describes a technical design concept for the CLIC damping wigglers.

The work on the creation of compact storage rings, superconducting rectangular magnet‐based synchrotron radiation (SR) sources produced jointly with the Association VACUUMMASHPRIBOR (Moscow) for technology and research purposes is described. The tests of a pilot model and the current status of work on SIBERIA‐SM and a stand for storage rings are reported. Also presented are the results of calculations concerning the field distribution and the dynamic aperture in the storage ring. New projects of SR sources, a 1.2‐GeV storage ring for micromechanics and a 2.4‐GeV storage ring, both having superconducting and warm magnets in their structure, are discussed.

A general presentation on the main storage ring of the Zelenograd Technological Research Center is given. The TNK SR source is intended to create a basis for the industrial realization of advanced X-ray lithographic technology. A modern analytical center for materials science will be established, based on the TNK facility.

The project for a compact storage ring SIBERIA-AS — a synchrotron radiation (SR) source for X-ray lithography with an electron energy of 600 MeV and an orbit circumference of about 3 m — is considered. The major component of the storage ring is a 3.8 T azimuthally symmetrical magnet consisting of annular superconducting coils without utilization of ferromagnetic material. The suggested design has enabled the effect of iron yoke saturation on the magnetic field distribution to be eliminated, and both the weight (about 8 tons) and the overall dimensions (a cylinder of 2 m in diameter and 2 m in height) to be considerably reduced. The basic systems of the storage ring are described and its parameters are reported.

The magnetic calculations of the individual dipoles and dipoles in “undulator environment” were executed by means of Mermaid 3D Code and these results were confirmed by magnetic measurements of the individual dipoles and the assembled undulators. The magnetic parameters of all dipoles were estimated on basis of the mechanical measurement of the dipole characteristics (pole gap, yoke width, coil position) and the main dependences obtained from magnetic calculations and measurements. These parameters were used for optimal placing of the dipoles in undulators (sorting). The special Hall probe system was designed and manufactured for magnetic measurements of the undulators. It allowed us to observe the inner structure of the magnetic fields. At a magnetic field measurement accuracy of ± 15 μT the accuracy of the 1st integral calculated on the basis of the measured magnetic fields is ∼ 50 μTm. All three undulators were magnetically measured at BINP and are being re‐measured at Soleil after transportation.

Three elliptical undulators HU256 of electromagnetic type were produced, tested and magnetically measured by the Budker Institute of Nuclear Physics (Russia) for Synchrotron Soleil (France). The undulators have a new design of a Bx & Bz closed structure for insertion vacuum chamber. In the elliptical undulator HU256 with period of the magnetic fields of 256 mm, the vertical magnetic field (Bzmax=0.44 T) formed by 27 Bz laminated dipole magnets is symmetric, and the horizontal magnetic field (Bxmax=0.33 T) formed by 28 Bx laminated dipole magnets is asymmetric. The undulator can work in standard mode as well as in a quasi‐periodical mode. The vertical magnetic field may be modulated by switching on the modulation coils placed on the Bz dipoles. Two power supply systems allow us to modulate the horizontal magnetic field, and change the radiation spectrum. The magnetic calculations of the individual dipoles and dipoles in “undulator” environment were executed by means of Mermaid 3D Code. The magnetic measurements of the individual dipoles had confirmed the magnetic calculations. On basis of semiempirical dependences from the mechanical characteristics the estimates of the magnetic parameters for all dipoles were calculated. Sorting of dipoles in the undulators have been done, and it has improved the magnetic parameters of the assembled undulators in comparison with the statistical estimations. The magnetic measurements of the undulators HU256 were carried out at Budker INP by Hall probes and at Soleil by Hall probes and Stretched Wire. Now the 1st undulator HU256 is installed at Soleil Storage Ring.

The Budker Institute of Nuclear Physics has a large experience in manufacturing superconducting magnets, including wigglers (special insertion devices) which are installed in straight sections of storage rings for increasing the photon flux or for improving the spectral features of the synchrotron radiation. The article describes the power supply and the quench protection system for a 7.5 T superconducting wiggler, produced for the new SR source PLS in Korea. The power supply and the quench protection system for the 7.5 T superconducting wiggler are described. The experimental measurements of the quench history and the training effect are presented. An output energy to a dumping resistance during quenching and a dumped energy inside the yoke are estimated.

To provide a user facility for the Siberian Centre of Photochemical Researches in Novosibirsk a high power free electron laser is under construction. The project status and installation are described.

The OK-4 is the first storage ring FEL operating in the United States. It was commissioned in November, 1996 and demonstrated lasing in the near UV and visible ranges (345-413 nm) with extracted power of 0.15 W. In addition to lasing, the OK-4/Duke FEL generated a nearly monochromatic (1% FWHM) /spl gamma/-ray beam. In this paper we describe the initial performance of the OK-4/Duke storage ring FEL and /spl gamma/-ray source.

We discuss the design and expected performance of the OK-5 FEL, which will replace in 2002 the OK-4 FEL operating now at the Duke storage ring. The OK-5 FEL is the first distributed optical klystron with variable polarization. The design of wigglers and matching sections is flexible for providing optimal conditions for variety of operation modes. In this paper we present calculations of the main OK-5 FEL parameters such as its tuning range, gain and lasing power. Based on our calculations we present the predictions for the OK-5 gamma-ray source. We conclude with description of the current status of the OK-5 FEL and plans for its installation.

Linearly and circularly polarized x-rays have been very successfully applied to the study of the properties of materials. Many applications can benefit from the availability of energy-tunable, high-brilliance x-ray beams with adjustable polarization properties. A helical undulator that can generate beams of variable (linear to circular) polarization has been designed and built by the Budker Institute of Nuclear Physics and the Advanced Photon Source. The first harmonic of this 12.8-cm-period device will cover the energy range from 0.4 keV to 3.5 keV. An important feature of this fully electromagnetic device is that it will allow us to generate 100% horizontally (Kx=0) or vertically (Ky=0) plane-polarized radiation, which will enable many experiments otherwise not technically feasible. With symmetric deflection parameters (Kx=Ky), the on-axis radiation will be circularly polarized, with a user-selectable handedness. The polarization can be changed at rates up to 10 Hz.

The mutual coherency of spontaneous radiation from two undulators separated by an achromatic bend was observed. An updated magnetic system with an optical klystron was implemented for this experiment. The experiments confirm theoretical expectations. The possible use of a similar technique for efficient power extraction from high-power free-electron lasers (FELs) is discussed. This experiment shows the importance of bend achromaticity for mutual coherency of spontaneous radiation from two undulators. >

A project for a race-track microtron-the beam source for a free-electron laser (FEL)-is considered. Utilized in the FEL, the beam will liberate its energy to the RF microtron system when, being decelerated, it passes along the same microtron orbits in inverse sequence. The layout of the microtron is depicted. The microtron comprises an injector, two magnetic straight systems with 180 degrees separating bend, a common straight section with RF cavities (the section is common to electrons of different energy), magnets for the injection and extraction systems, solenoidal magnetic lenses, four separated straight sections with magnetic quadrupole lenses, a FEL magnetic system placed in the fourth straight section, and a beam dump. The design energy of electrons is 35 MeV and the mean current ranges from 0.1 to 1 A. >

The OK-4/Duke storage ring FEL was commissioned in November 1996 and demonstrated lasing in the near UV and visible ranges (345 - 413 nm). The OK-4 is the first storage ring FEL with the shortest wavelength and highest power for UV FELs operating in the United States. During one month of operation we have performed preliminary measurements of the main parameters of the OK-4 FEL: its gain, lasing power and temporal structure. In addition to lasing, the OK-4/Duke FEL generated a nearly monochromatic (1% FWHM) 12.2 MeV gamma-ray beam. In this paper we describe the design and initial performance of the OK-4/Duke storage ring FEL. We compare our predictions with lasing results. Our attempt to lase in the deep UV range (around 193 nm) is discussed. The OK-4 diagnostic systems and performance of its optical cavity are briefly described.

To provide the user facility for Siberian Center of Photochemical Researches in Novosibirsk the high power free electron laser is under construction. The project status and installation are described.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The physics programme and the design are described of a new collider for particle and nuclear physics, the Large Hadron Electron Collider (LHeC), in which a newly built electron beam of 60 GeV, to possibly 140 GeV, energy collides with the intense hadron beams of the LHC. Compared to the first ep collider, HERA, the kinematic range covered is extended by a factor of twenty in the negative four-momentum squared, Q^2, and in the inverse Bjorken x, while with the design luminosity of 1e33 cm-2 s-1 the LHeC is projected to exceed the integrated HERA luminosity by two orders of magnitude. The physics programme is devoted to an exploration of the energy frontier, complementing the LHC and its discovery potential for physics beyond the Standard Model with high precision deep inelastic scattering measurements. These are designed to investigate a variety of fundamental questions in strong and electroweak interactions. The LHeC thus continues the path of deep inelastic scattering (DIS) into unknown areas of physics and kinematics. The physics programme also includes electron-deuteron and electron-ion scattering in a (Q^2 1/x) range extended by four orders of magnitude as compared to previous lepton-nucleus DIS experiments for novel investigations of neutron's and nuclear structure, the initial conditions of Quark-Gluon Plasma formation and further quantum chromodynamic phenomena. The LHeC may be realised either as a ring-ring or as a linac-ring collider. Optics and beam dynamics studies are presented for both versions, along with technical design considerations on the interaction region, magnets including new dipole prototypes, cryogenics, RF, and further components. A design study is also presented of a detector suitable to perform high precision DIS measurements in a wide range of acceptance using state-of-the art detector technology, which is modular and of limited size enabling its fast installation. The detector includes tagging devices for electron, photon, proton and neutron detection near to the beam pipe. Civil engineering and installation studies are presented for the accelerator and the detector. The LHeC can be built within a decade and thus be operated while the LHC runs in its high-luminosity phase. It so represents a major opportunity for progress in particle physics exploiting the investment made in the LHC.

Erratum to: ‘‘Status of the Siberian Synchrotron Radiation Center’’ [Nucl. Instr. and Meth. A 543 (2005) 1] A.I. Ancharov, V.B. Baryshev, V.A. Chernov, A.N. Gentselev, B.G. Goldenberg, D.I. Kochubei, V.N. Korchuganov, G.N. Kulipanov , M.V. Kuzin, E.B. Levichev, N.A. Mezentsev, S.I. Mishnev, A.D. Nikolenko, V.E. Panchenko, V.F. Pindyurin, M.A. Sheromov, B.P. Tolochko, M.R. Sharafutdinov, A.N. Shmakov, N.A. Vinokurov, P.D. Vobly, K.V. Zolotarev Institute of Solid State Chemistry and Mechanochemistry of SB RAS, 630090 Novosibirsk, Russian Federation Budker Institute of Nuclear Physics of SB RAS, 630090 Novosibirsk, Russian Federation Boreskov Institute of Catalysis SB RAS, 630090 Novosibirsk, Russian Federation

A method of extracting radiation from the optical cavity of a free electron laser using an insignificant bend of the electron beam is discussed, noting that the modulation of its longitudinal density needs to be conserved. Modernization of the optical klystron magnetic system of the VEPP-3 storage ring has made it possible to realize an achromatic bend of electrons between two undulators. In such a case the mutual coherence of the radiation from the undulators has been demonstrated by means of Young's interference experiment. The experimental results confirm the possibility of implementing the suggested technique for radiation extraction.