Author: Colldelram, C.
Paper Title Page
MOTC01
Optics and Mechanics of Mirror Benders  
 
  • J. Nicolás, C. Colldelram, C. Ruget
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  We will explain the basic concepts of optics regarding focusing with grazing incidence reflective surfaces. The concept of aberration and figure error, and the aberrations associated to the typical geometric surfaces found in mirrors will be described with some detail. We will describe how mirror benders can approximate these geometrical figures, how to compute the required mechanical characteristics, and the optical effect of the residual errors. Finally, we will describe, and illustrate with examples, the main aspects that have to be considered in the mechanical implementation, their characterization and their operation in the beam-line.  
slides icon Slides MOTC01 [7.335 MB]  
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MOPE01 Stabilization Methods for Force Actuators and Flexure Hinges 1
 
  • C. Colldelram, J. Nicolás, C. Ruget
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  In the framework of the design of an adaptive optics for x-ray mirrors a stabilization system* for force actuators and flexure hinges have been conceived. This corrector allows to deform the mirror surface at nanometre level but for this purpose it requires resolutions better than 0.02, by using ultra-low constant springs, and to preserve the introduced deformation it is needed to be stable at the same level. The corrector needs to be insensitive when dismantling and remounting the mirror. In the other hand in order to support the corrector its structure is attached to the bender frame and the spring force is transmitted through a level arm by means a bearing articulation. This introduces a small friction but it is still preferably to eliminate it. A new method based -k spring-like constant principle is proposed. Based on this technique it is possible to stabilize the force exerted on the mirror below 0,02N for an error range more than 1 mm. In addition applying the principle to a flexure it allows to compensate it in an angular range in within the torque variation tend to be null, below 0,005 Nm, thus becoming a short range, frictionless and zero torque articulation.
* Patent Registered
 
poster icon Poster MOPE01 [1.046 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-MOPE01  
About • paper received ※ 15 September 2016       paper accepted ※ 08 May 2017       issue date ※ 22 June 2017  
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MOPE41 Design and Construction of a PW Experimental System of HV Chamber Adaptable, Modular and Stable 99
 
  • A. Carballedo, C. Colldelram, J.R. García, R. Monge, L. Nikitina
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
  • J. Hernandez-Toro, L. Roso
    CLPU, Villamayor, Spain
 
  Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no 654148 Laserlab-Europe
In the recent years, the number of high power lasers devoted to particle acceleration has increased in Europe. Additionally to this, some synchrotrons and accelerators are integrating these lasers in its lines, increasing the scientific synergies. The HP laser must be transported in HV. The use of HV also permits good cleanliness in the optical set up. As addition, is necessary to create an adaptable and modular design where several chambers could be assembled together. One additional constrain is the stability. A new model of HV chambers is presented. These consist in a frame where the walls are exchangeable panels, which make easier the introduction of a new configuration of ports. The system was designed as construction blocks. For a proper connection of the chambers a new interior fixation and pushers system was designed. Thanks to this, coupling new HV chambers, the volume total can be also easily modified. Finally, a third generation decoupled system is integrated inside, consisting of a stable breadboard, this supported by six columns that implement a preloaded kinematical mount, providing both an outstanding stability and a fine regulation (1st RM: 77Hz).
 
poster icon Poster MOPE41 [0.938 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-MOPE41  
About • paper received ※ 09 September 2016       paper accepted ※ 20 September 2016       issue date ※ 22 June 2017  
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MOPE42 Experimental and Numerical Study of the ALBA LINAC Cooling System 102
 
  • M. Ferrater
    UPC, Barcelona, Spain
  • J.J. Casas, C. Colldelram, D. Lanaia, R. Muñoz Horta, F. Pérez, M. Quispe
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  This work investigates experimentally and numerically the performance of the ALBA LINAC cooling system. The main objective is to enhance the hydraulic system in order to significantly improve its thermal and water flow stability. In normal operation some problems have been identified that affect the performance of the LINAC: flowrate below the nominal values and water flow decreasing in time. The cooling subsystems have been experimentally characterized in terms of the pressure drop and flowrate. The measurements were taken using a portable hydraulic unit made at ALBA as well as a set of ultrasonic flowmeters. For the numerical studies the cooling network has been simulated using the software Pipe Flow Expert. The experimental results have shown that a number of components are too restrictive. In some cases the possibility to increase the flowrate is limited. The numerical results show that the velocity magnitude is inadequate in some places, producing air bubble entrapment, high pressure drop at pipes and insufficient flow. Based on this study several modifications are presented in order to raise the nominal flow and to adequate the water flow velocities between 0.5 and 3 m/s.  
poster icon Poster MOPE42 [1.073 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-MOPE42  
About • paper received ※ 09 September 2016       paper accepted ※ 15 September 2016       issue date ※ 22 June 2017  
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MOPE43 Hydraulic Failure Caused by Air in Pipelines of the Experimental Area Ring of ALBA Synchrotron Light Source: Research, Simulations and Solutions 105
 
  • L. Macià
    UPC, Barcelona, Spain
  • J.J. Casas, C. Colldelram, M. Quispe
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  After five years in operation of the ALBA Synchrotron Light Source a hydraulic failure caused a maximum decreasing of water flow about 40% of its nominal value, hampering the refrigeration of the local components. The problem was mainly caused by the air accumulated in pipes due to very low velocities of water flow. A literature review was conducted about the minimum water flow velocity for removing air in pipelines as design criteria. The aim of this work is to develop hydraulic solutions in order to achieve the minimum flowrate in pipelines of the Experimental Area (EA) ring. In the short term it is proposed to install a controlled bypass in the EA. A numerical simulation using the software Pipe Flow Expert has been implemented in order to determine the requirements of the bypass that works under different conditions to assure a minimum flowrate all along the ring. The velocity map in EA ring is simulated for different scenarios: 180 and 360 degrees distribution for both clockwise and anticlockwise rotation. For the long term a design of pipes with variable cross section is proposed which optimizes the flow velocity magnitude in EA ring in agreement with the design criteria.  
poster icon Poster MOPE43 [1.347 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-MOPE43  
About • paper received ※ 10 September 2016       paper accepted ※ 15 September 2016       issue date ※ 22 June 2017  
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TUAA00
Welcome and Overview  
 
  • C. Colldelram, D. Lopez Nonell
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  In this talk a briefing of the scientific program is presented. This is the first time that MEDSI uses JACoW and it is shown a preliminary evaluation of how the publisher has worked with some figures about the abstract submission, the status of the paper submission as well as the how it works the papers edition. Then a revision of the conference topics is explained as have been organized jointly with the International Organizing Committee and how this topic are organized in the conference program for the Contributed Orals as well as posters. Finally a list of interesting statistics and figures about the conference are presented. This is one of the most successful MEDSI’s in all point of views, number of delegates, abstract submission, as well as sponsors and a final review of the delegates per facility. And last the formal conference opening is announced.  
slides icon Slides TUAA00 [10.493 MB]  
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TUPE05 Numerical Simulation of the ALBA Synchrotron Light Source Cooling System Response for Failure Prevention 162
 
  • X. Escaler
    UPC, Barcelona, Spain
  • J.J. Casas, C. Colldelram, M. Prieto, M. Quispe
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  The ALBA Synchrotron Light Source cooling system is designed with a common return pipe that interconnects the four consumption rings. Such configuration is believed to compromise its optimal operation. To understand its thermo-fluid dynamic behaviour, a detailed 1D model has been built comprising all the components such as the pipes, fittings, bends, valves, pumping stations, heat exchangers and so on, and the various regulation mechanisms. Preliminarily, the model results in steady state operating conditions have been compared with experimental measurements and the maximum deviations have been found below 13%. Then, a series of transient numerical simulations have been carried out to determine the system response. Specifically, effects of the blockage and leakage of a consumption line as well as the increase and decrease of heat duty for the tunnel rings have been investigated. As a result, the stability of the system has been evaluated and the operational limits have been estimated in front of hydraulic and thermal load variations. Moreover, particular behaviors have been identified which can be used to design monitoring and control strategies to prevent unexpected failures.  
poster icon Poster TUPE05 [0.615 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-TUPE05  
About • paper received ※ 07 September 2016       paper accepted ※ 21 September 2016       issue date ※ 22 June 2017  
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TUPE06 Thermo-Fluid Numerical Simulation of the Crotch Absorbers’ Cooling Pinholes for ALBA Storage Ring 165
 
  • X. Escaler, V. Arbo Sangüesa
    UPC, Barcelona, Spain
  • J.J. Casas, C. Colldelram, M. Prieto, M. Quispe
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  The ALBA Synchrotron Light Facility crotch absorbers, that remove the unused storage ring radiation, incorporate an internal cooling system composed by a number of parallel pinholes and by the corresponding stainless steel inner tubes inserted into each of them. Water flows in the resulting annular sections to evacuate the total heat power. Around each inner tube, a spiral wire is fixed along the whole length with a given pitch height in order to enhance the convection heat transfer. The influence of several design parameters on the absorber thermo-fluid behavior has been evaluated by means of the CFD software ANSYS CFX. In particular, the wall heat transfer coefficients and the pressure losses through a single pinhole have been evaluated for a range of different flow rates and pitch heights. Moreover, some modifications of the end wall geometry have been simulated as well as the effect of reversing the flow direction inside the channels. Finally, the critical crotch absorber type 3 has also been simulated and the limiting pitch height-flow rate combinations have been found based on the available driving pressure of the cooling system.  
poster icon Poster TUPE06 [1.546 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-TUPE06  
About • paper received ※ 07 September 2016       paper accepted ※ 21 September 2016       issue date ※ 22 June 2017  
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TUPE11 Study on Thermal Mechanical Design and Optimization Analysis for the ALBA Infrared Microspectroscopy Beamline (MIRAS) Extraction Mirror Based on Finite Element Analysis 179
 
  • M. Quispe, A. Carballedo, J.J. Casas, C. Colldelram, A. Crisol, G. Peña, L. Ribó, I. Sics, I. Yousef
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  This paper reports design, modelling, simulation and optimization results for the ALBA MIRAS infrared radiation extraction mirror. Finite element analysis (FEA) was used to simulate the thermal mechanical behaviour of the device. With the aim to ensure a good thermal performance, conservative assumptions were applied: all of the incident Bending Magnet (BM) radiation is absorbed at the mirror surface, constant bending magnetic field and low thermal contact between the mirror Al 6061 and the OFHC copper arm. A novel solution has been implemented in order to provide an effective cooling by a natural convection on the in-air part of extraction mirror assembly. This has voided the necessity for a water cooling that often causes problems due to the associated vibrations. The power conditions were calculated by using SynRad+. The main ALBA Storage Ring design parameters are: 3 GeV, 400 mA and 1.42 T. According to these conditions, the mirror absorbs 15 W with a peak power density of 0.51 W/mm2. The peak temperature calculated was 63.2 °C. The real measurements reported during the commissioning stage showed a good thermal performance, in agreement with the results predicted by FEA.  
poster icon Poster TUPE11 [0.881 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-TUPE11  
About • paper received ※ 09 September 2016       paper accepted ※ 15 September 2016       issue date ※ 22 June 2017  
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TUPE13 Numerical Simulation of the ALBA Synchrotron Light Source Cooling System Response to Pump Start-Up and Shut-Down 187
 
  • X. Escaler, D. Juan Garcia
    UPC, Barcelona, Spain
  • J.J. Casas, C. Colldelram, M. Prieto, M. Quispe
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  The ALBA Synchrotron Light Source cooling system is submitted to regular pump start-ups and shut-downs. Moreover, pumps can trip due to motor power failures. As a result, the piping system can be subjected to surges and pressure oscillations. The 1D thermo-fluid simulation software Flowmaster has been used to predict these transient conditions taking into account the fluid compressibility, the pipe elasticity, the characteristic time response of the check valves and the pump/motors moments of inertia. During pump start-ups, significant pressure rises are detected that can be reduced by readjusting the PID controller parameters. Unexpected pump shut-downs do not appear to provoke significant water hammer conditions. However, pressure fluctuations are generated mainly in the same pumping line but also in the rest of the system due to the particular common return configuration. In all the cases the pressure regulation mechanisms acting on the pump rotating speeds serve to attenuate the consequences of these transients. Finally, the feasibility of the model to simulate the effect on the system response of trapped air inside the pipes has also been evaluated.  
poster icon Poster TUPE13 [0.743 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-TUPE13  
About • paper received ※ 07 September 2016       paper accepted ※ 22 September 2016       issue date ※ 22 June 2017  
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TUPE14 Study, Design and Optimization Analysis of the ALBA LOREA Dipole Vacuum Chamber and Crotch Absorbers Based on Finite Element Analysis 191
 
  • M. Quispe, J. Campmany, J.J. Casas, C. Colldelram, A. Crisol, J. Marcos, G. Peña, M. Tallarida
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  This work deals with the FEA study, design and optimization of the LOREA dipole vacuum chamber and Glidcop Al-15 crotch absorbers. At present LOREA is the ninth beam-line being designed at ALBA with an Insertion Device (ID) consisting of an Apple II-type helical undulator. For the standard dipole chamber the vertical polarized light hits the walls because of the very narrow vertical aperture between the cooling channels. In vertical mode the ID vertical divergence equals ± 2.2 mrad and the peak power density and total power are 5.6 kW/mrad² and 5.5 kW, respectively. Due to the high power a temperature as high as more than 600 °C is calculated. In consequence the dipole chamber has to be modified and the absorbers have to withstand the Bending Magnet (BM) and ID radiation. The new absorbers have to be thicker and its cooling channels are farer from BM power deposition than the standard absorbers. The thermal mechanical simulations show good results, the new absorbers are in a safe range, the maximum temperature, stress and strain are 309.2 °C, 164.2 MPa and 0.14%, respectively. The main ALBA Storage Ring design parameters used in the simulations are: 3 GeV, 400 mA and 1.42 T (BM).  
poster icon Poster TUPE14 [1.524 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-TUPE14  
About • paper received ※ 09 September 2016       paper accepted ※ 15 September 2016       issue date ※ 22 June 2017  
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WEPE15 High Frequency UHV Mechanical X-Ray Beam Chopper 339
 
  • N González, C. Colldelram, C. Escudero, S. Ferrer
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  A mechanical chopper* has been designed and built to perform X-ray Absorption Spectroscopy (XAS) experiments with operating liquid electrochemical cells at NAPP end station of ALBA Synchrotron (BL24, CIRCE). When operating the cell, to separate the weak currents induced by the X-ray absorption process at the electrode in contact with the electrolyte (TEY signal) from the faradaic current set between the electrodes, the incoming beam must be chopped at a certain frequency (w). Then, using a lock in amplifier, the signal at this frequency w can be extracted and measured. When the chopper is located in the beam path, it produces pulses with a frequency w, modulating the TEY signal. The chopper developed at ALBA, with variable frequency, improves previous designs which used piezo-actuated choppers constrained to work at fixed oscillating frequencies**. The design consists of a slotted disk that spins around an axis by means of an UHV stepper motor. A LED and photodiode based UHV sensor ensures that frequency drifts do not affect the measurements. The motor is hold by an internally water cooled OFHC support, which allows long duration experiments at high speeds without stopping.
* Patent Registered
** Velasco-Velez et al, Science 2014, 346, 831-834
 
poster icon Poster WEPE15 [4.043 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-WEPE15  
About • paper received ※ 09 September 2016       paper accepted ※ 16 September 2016       issue date ※ 22 June 2017  
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WEPE40 Two-rotation Mechanism for an in Vacuum Beamstop 378
 
  • J.B. González Fernández, C. Colldelram, A. Fontserè Recuenco, G. Jover-Mañas, J. Ladrera Fernández, M. Malfois, J.C. Martínez Guil
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  At Small-angle X-ray Scattering beamlines (SAXS), beamstops are needed to block the intense primary beam that has not been scattered by the sample in order to protect the detector from any damage. Beamstops are usually confined inside a vacuum tube minimizing air space between the sample and the detector. For certain experiments, a motorized beamstop is required to achieve a precise positioning in different regions of the detector active area. ALBA has developed a new motorized beamstop* consisting of a two-rotation mechanism inside vacuum that composes a movement able to cover all range of the active area of the detector. The presented solution involves a main rotation reached by a gear and a worm drive actuated by a stepper motor and a second rotation relative to the main one produced by a piezo rotation stage. For each position appears two different solutions. This characteristic permits take two equivalent images in the detector with the same beamstop position but different orientation in the beamstop support; thus permitting the compensation of the support shadow on the active area of the detector.
* Patent Registered
 
poster icon Poster WEPE40 [2.217 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-WEPE40  
About • paper received ※ 08 September 2016       paper accepted ※ 16 September 2016       issue date ※ 22 June 2017  
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FRAA03 Mechanical Design of MIRAS, Infrared Microspectroscopy Beam Line at ALBA Synchrotron 403
 
  • L.R.M. Ribó, C. Colldelram, A. Crisol, A.A. Gevorgyan, R. Monge, J. Nicolás, L. Nikitina, M. Quispe, I. Sics, I. Yousef
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
  • P. Dumas
    SOLEIL, Gif-sur-Yvette, France
  • G. Ellis
    CSIC, Madrid, Spain
 
  The infraredμspectroscopy beam line has been an In House project fully developed at ALBA as a result of a collaboration of different teams during the period 2014 where the design started to 2016 It is composed by a retractile mirror to extract the IR light from the bending magnet radiation and a system of 8 transport mirrors located by positioning systems designed for a high stability performance, to transport the extracted light outside the tunnel until the first End Station  
slides icon Slides FRAA03 [5.469 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-FRAA03  
About • paper received ※ 09 September 2016       paper accepted ※ 20 September 2016       issue date ※ 22 June 2017  
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FRBA02 The Nanobender: A New X-Ray Mirror Bender With Nanometer Figure Correction 413
 
  • C. Colldelram, J. Nicolás, P. Pedreira, L. Ribó, C. Ruget, I. Sics
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
  • J.M. Casalta Escuer, C. Martín-Nuño Gonzalez, A. Tomas Justribo, D. Úbeda Gonzalez
    SENER, Cerdanyola del Vallès, Spain
 
  Over time X-Ray mirrors are demanded for better focusing, closer to sample refocusing, spot size as well as better beam uniformity at sample position. Based on the experience of ALBA Phase I beam lines a new alter-native design of a mirror bender* is proposed. The system includes two main functionalities: the mirror bender mechanism and mirror figure error correc-tion. Both mechanisms are based on the introduction of a force constrain on the mirror surface instead of a geometrical one. As being based on a force mechanism they could reach high resolution and especially for the correctors which can achieve nanometre resolution. The correctors are designed to provide high force stability in the mirror side, eliminating the crosstalk between bending and figure correction, and minimizing the sensitivity to drifts. With such controlled deformation of the mirror substrate it is possible to obtain the desired surface figure not only to correct mirror figure errors but also to adapt it to the incident wavefront, thus becoming adaptive system. The mechanical solutions are presented which are able to correct mirror surfaces with a resolution of 1 nm reaching slope errors below 100 nrad.
* Patent Registered
 
slides icon Slides FRBA02 [4.766 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-MEDSI2016-FRBA02  
About • paper received ※ 03 October 2016       paper accepted ※ 08 May 2017       issue date ※ 22 June 2017  
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FRBA05
Closing Remarks  
 
  • C. Colldelram
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  Closing remarks for MEDSI2016 is a briefing of how the conference has been developed. Starting with an Introduction from the Head of Engineering Division at ALBA, Mr. Joan Casas, giving thanks to the different organization parites, followed by more technical presentation by the Transversal Section Head, Mr. Carles Colldelram, with few more statistics about the number of contributions for oral talks and also poster presentations, revision of the paper submission status, number of delegates and its evolution since last MEDSI editions, delegates per facility, reminder and thanks to the sponsors, a thanks to the session’s chairman and encouragement to young engineers to participate to the conferences as chairman, and a global thanks to everybody. Finally is closed by few general deliberations about the conference by the IOC Chairman, Mr. Jim Kay.  
slides icon Slides FRBA05 [27.835 MB]  
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