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Sample records for autonomous star tracker

  1. Autonomous Star Tracker Algorithms

    DEFF Research Database (Denmark)

    Betto, Maurizio; Jørgensen, John Leif; Kilsgaard, Søren;

    1998-01-01

    Proposal, in response to an ESA R.f.P., to design algorithms for autonomous star tracker operations.The proposal also included the development of a star tracker breadboard to test the algorithms performances.......Proposal, in response to an ESA R.f.P., to design algorithms for autonomous star tracker operations.The proposal also included the development of a star tracker breadboard to test the algorithms performances....

  2. Autonomous star tracker based on active pixel sensors (APS)

    Science.gov (United States)

    Schmidt, U.

    2004-06-01

    Star trackers are opto-electronic sensors used onboard of satellites for the autonomous inertial attitude determination. During the last years, star trackers became more and more important in the field of the attitude and orbit control system (AOCS) sensors. High performance star trackers are based up today on charge coupled device (CCD) optical camera heads. The Jena-Optronik GmbH is active in the field of opto-electronic sensors like star trackers since the early 80-ties. Today, with the product family ASTRO5, ASTRO10 and ASTRO15, all marked segments like earth observation, scientific applications and geo-telecom are supplied to European and Overseas customers. A new generation of star trackers can be designed based on the APS detector technical features. The measurement performance of the current CCD based star trackers can be maintained, the star tracker functionality, reliability and robustness can be increased while the unit costs are saved.

  3. In Orbit Performance of a Fully Autonomous Star Tracker

    DEFF Research Database (Denmark)

    Jørgensen, John Leif

    1999-01-01

    The Department of Automation at DTU has developed the Advanced Stellar Compass (ASC), a fully autonomous star tracker, for use as high precision attitude reference onboard spacecrafts. The ASC is composed of a CCD-based camera and a powerful microprocessor containing star catalogue, image...

  4. CLOSED LOOP AOCS TESTING OF AN AUTONOMOUS STAR TRACKER

    DEFF Research Database (Denmark)

    Jørgensen, John Leif

    1999-01-01

    . It is a fully autonomous star tracker intended as a high accuracy attitude reference onboard spacecrafts. The ASC consists of a miniaturized but powerful microcomputer driving from one to four CCD-based camera heads. The use of multiple camera heads may relieve several constraints on the AOCS, such as increased...... maximum attitude rate of change, and a "don't-care" inertial pointing, because multiple cameras may be arranged such that simultaneous blinding by the Sun and Earth are highly unlikely.On the other hand, to stimulate an old-fashioned star tracker, it only took a single moving light source, whereas...... not even a high quality star pattern generator may be able to pass the outlier rejection filtering of the ASC thus efficiently precluding artificial stimuli during AIT tests. In order to circumvent this impasse, the ASC has a series of build-in features enabling simple, yet comprehensive, closed loop...

  5. Miniature Autonomous Star Tracker Based on CMOS APS

    OpenAIRE

    Ying, Dong; Zheng, You; Fei, Xing; Qin, Chou

    2006-01-01

    An APS (Active Pixel Sensor) based autonomous star tracker (AAST) has been proposed for small satellite and microsatellite attitude determination. A prototype of AAST has been developed. It has low mass of 1kg, low power of 3W, high rate up to 5Hz, and acquisition success rate of higher than 99.9%. The improvements in dimensions and performances are realized with the replacement of the CCD (Charge Coupled Device) by the APS. The optical design of the prototype is based on PSF (Point Spread Fu...

  6. On-Orbit Performance of Autonomous Star Trackers

    Science.gov (United States)

    Airapetian, V.; Sedlak, J.; Hashmall, J.

    2001-01-01

    This paper presents the results of a performance study of the autonomous star trackers (ASTs) on the IMAGE and the EO-1 spacecraft. IMAGE is a spinning spacecraft without gyros or redundant precision attitude sensors, so the statistical properties of the AST are estimated simply by comparing the output observed quaternions with a rigid rotator model with constant angular momentum. The initial conditions are determined by a least-squares fit to minimize the AST residuals. An additional fit is used to remove the remaining systematic error and to obtain the inherent sensor noise. Gyro rate data are available for the EO-1 mission, so the AST noise statistics are obtained from the residuals after solving for an epoch attitude and gyro bias also using a least-squares method.

  7. Operational Experience with Autonomous Star Trackers on ESA Interplanetary Spacecraft

    Science.gov (United States)

    Lauer, Mathias; Jauregui, Libe; Kielbassa, Sabine

    2007-01-01

    Mars Express (MEX), Rosetta and Venus Express (VEX) are ESA interplanetary spacecrafts (S/C) launched in June 2003, March 2004 and November 2005, respectively. Mars Express was injected into Mars orbit end of 2003 with routine operations starting in spring 2004. Rosetta is since launch on its way to rendezvous comet Churyumov-Gerasimenko in 2014. It has completed several test and commissioning activities and is performing several planetary swingbys (Earth in spring 2005, Mars in spring 2007, Earth in autumn 2007 and again two years later). Venus Express has also started routine operations since the completion of the Venus orbit insertion maneuver sequence beginning of May 2006. All three S/C are three axes stabilized with a similar attitude and orbit control system (AOCS). The attitude is estimated on board using star and rate sensors and controlled using four reaction wheels. A bipropellant reaction control system with 10N thrusters serves for wheel off loadings and attitude control in safe mode. Mars Express and Venus Express have an additional 400N engine for the planetary orbit insertion. Nominal Earth communication is accomplished through a high gain antenna. All three S/C are equipped with a redundant set of autonomous star trackers (STR) which are based on almost the same hardware. The STR software is especially adapted for the respective mission. This paper addresses several topics related to the experience gained with the STR operations on board the three S/C so far.

  8. The MONS Star Trackers

    CERN Document Server

    Bedding, T R; Bedding, Timothy R.; Kjeldsen, Hans

    2000-01-01

    The MONS satellite will have two Star Trackers to sense the spacecraft attitude, and we plan to use them as scientific instruments to perform high-precision photometry of thousands of stars. We briefly describe the current plans for the Star Trackers and their expected capabilities.

  9. Intelligent Star Tracker

    OpenAIRE

    Clark, Natalie; Furth, Paul; Horan, Steven

    2000-01-01

    We describe our Intelligent Star Tracker System. Our Intelligent Star Tracker System incorporates an adaptive optic catadioptric telescope in a silicon carbide housing. Leveraging off of our active optic technologies, the novel active pixel position sensors (APPS) enable wide dynamic range and allows simultaneous imagery of faint and bright stars in a single image. Moreover, the APPS, in conjunction with the adaptive optics technologies, offer unprecedented accuracy in altitude and navigation...

  10. Interferometric star tracker Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Optical Physics Company (OPC) proposes to develop a high accuracy version of its interferometric star tracker capable of meeting the milli-arcsecond-level pointing...

  11. Vidicon star tracker.

    Science.gov (United States)

    Schuck, W H

    1966-04-01

    In many applications of star trackers, extremely short acquisition times, as well as accuracy and sensitivity, are required. Tracking systems employing the vidicon as a radiation sensor have been shown to provide the necessary speed of acquisition for such applications. This paper discusses the various theoretical and practical considerations involved in using the vidicon as a sensor in a star tracking system. A typical system configuration including telescope, sensor, and processing electronics is presented. The various optical and sensor parametric relationships required in the design of a vidicon star tracker are fully discussed and analyzed. PMID:20048884

  12. Star trackers for attitude determination

    DEFF Research Database (Denmark)

    Liebe, Carl Christian

    1995-01-01

    a CCD camera and a powerful microcomputer. The instruments are called star trackers and they are capable of determining the attitude with an accuracy better than 1 arcsecond. The concept of the star tracker is explained. The obtainable accuracy is calculated, the numbers of stars to be included...... in the star catalogue are discussed and the acquisition of the initial attitude is explained. Finally the commercial market for star trackers is discussed...

  13. STAR Integrated Tracker

    CERN Document Server

    Rose, A

    2003-01-01

    We present the design and performance analysis of a new integrated track reconstruction code developed for the STAR experiment at RHIC. The code is meant to replace multiple previous tracking codes written in FORTRAN many years ago, and to readily enable the integration of new and varied detector components. The new tracker is written from the ground up in C++ using a strong object-oriented model. Key features include an abstract geometry model for representation of detector components, a flexible track representation model, a built-in KALMAN filter for track parameter determination, and a powerful object factory model for fast handling of numerous small objects, such as hits and tracks. The new tracker will be deployed and used for analysis of data aquired during the RHIC year 3 run of the STAR experiment.

  14. STAR Integrated Tracker

    OpenAIRE

    Rose, A.

    2003-01-01

    We present the design and performance analysis of a new integrated track reconstruction code developed for the STAR experiment at RHIC. The code is meant to replace multiple previous tracking codes written in FORTRAN many years ago, and to readily enable the integration of new and varied detector components. The new tracker is written from the ground up in C++ using a strong object-oriented model. Key features include an abstract geometry model for representation of detector components, a fle...

  15. STAR heavy flavor tracker

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Hao

    2014-11-15

    Hadrons containing heavy quarks are a clean probe of the early dynamic evolution of the dense and hot medium created in high-energy nuclear collisions. To explore heavy quark production at RHIC, the Heavy Flavor Tracker (HFT) for the STAR experiment was built and installed in time for RHIC Run 14. The HFT consists of four layers of silicon detectors. The two outermost layers are silicon strip detectors and the two innermost layers are made from state-of-the-art ultra-thin CMOS Monolithic Active Pixel Sensors (MAPS). This is the first application of a CMOS MAPS detector in a collider experiment. The use of thin pixel sensors plus the use of carbon fiber supporting material limits the material budget to be only 0.4% radiation length per pixel detector layer, enabling the reconstruction of low p{sub T} heavy flavor hadrons. The status and performance of the HFT in the RHIC 200 GeV Au + Au run in 2014 are reported. Very good detector efficiency, hit residuals and track resolution (DCAs) were observed in the cosmic ray data and in the Au + Au data.

  16. Focal Adjustment for Star Tracker

    OpenAIRE

    Liu Hai-bo; Jian-kun Yang; Ji-chun Tan; De-zhi Su; Wen-liang Wang; Xiu-jian Li; Hui Jia

    2010-01-01

    Technique of measuring intensity distribution and size of spot image developed has been discussed, which is especially suitable for defocus adjustment in ground test of star tracker. A novel approach for choosing a proper defocusing position has been proposed based on collimator, Gaussian surface fitting method, and other ordinary instruments. It proves to be practical and adequate in the development of distant object tracking such as star tracker.Defence Science Journal, 2010, 60(6), pp.678-...

  17. Advanced Exoplanet Star Tracker for Orbit Self Determination Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal puts forth an innovative star tracker hardware sensor that allows for autonomous calculation of a spacecraft's orbit by employing Doppler Spectroscopy...

  18. Space Shuttle Star Tracker Challenges

    Science.gov (United States)

    Herrera, Linda M.

    2010-01-01

    The space shuttle fleet of avionics was originally designed in the 1970's. Many of the subsystems have been upgraded and replaced, however some original hardware continues to fly. Not only fly, but has proven to be the best design available to perform its designated task. The shuttle star tracker system is currently flying as a mixture of old and new designs, each with a unique purpose to fill for the mission. Orbiter missions have tackled many varied missions in space over the years. As the orbiters began flying to the International Space Station (ISS), new challenges were discovered and overcome as new trusses and modules were added. For the star tracker subsystem, the growing ISS posed an unusual problem, bright light. With two star trackers on board, the 1970's vintage image dissector tube (IDT) star trackers track the ISS, while the new solid state design is used for dim star tracking. This presentation focuses on the challenges and solutions used to ensure star trackers can complete the shuttle missions successfully. Topics include KSC team and industry partner methods used to correct pressurized case failures and track system performance.

  19. Focal Adjustment for Star Tracker

    Directory of Open Access Journals (Sweden)

    Liu Hai-bo

    2010-10-01

    Full Text Available Technique of measuring intensity distribution and size of spot image developed has been discussed, which is especially suitable for defocus adjustment in ground test of star tracker. A novel approach for choosing a proper defocusing position has been proposed based on collimator, Gaussian surface fitting method, and other ordinary instruments. It proves to be practical and adequate in the development of distant object tracking such as star tracker.Defence Science Journal, 2010, 60(6, pp.678-682, DOI:http://dx.doi.org/10.14429/dsj.60.36

  20. Optical filtering for star trackers

    Science.gov (United States)

    Wilson, R. E.

    1973-01-01

    The optimization of optical filtering was investigated for tracking faint stars, down to the fifth magnitude. The effective wavelength and bandwidth for tracking pre-selected guide stars are discussed along with the results of an all-electronic tracker with a star tracking photomultiplier, which was tested with a simulated second magnitude star. Tables which give the sum of zodiacal light and galactic background light over the entire sky for intervals of five degrees in declination, and twenty minutes in right ascension are included.

  1. Star trackers for attitude determination

    OpenAIRE

    Liebe, Carl Christian

    1995-01-01

    One problem comes to all spacecrafts using vector information. That is the problem of determining the attitude. This paper describes how the area of attitude determination instruments has evolved from simple pointing devices into the latest technology, which determines the attitude by utilizing a CCD camera and a powerful microcomputer. The instruments are called star trackers and they are capable of determining the attitude with an accuracy better than 1 arcsecond. The concept of the star tr...

  2. Towards Star Tracker Only Attitude Estimation

    OpenAIRE

    Enright, John; Sinclair, Doug; Grant, Cordell; McVittie, Geoff; Dzamba, Tom

    2010-01-01

    Star trackers can provide full information about satellite attitude information from a single sensor. In this paper, we examine the feasibility of designing attitude determination systems using only star trackers. Star trackers can provide direct inertial attitude estimates without the need for sensor fusion, but current sensors are not robust enough to provide effective attitude estimates in all mission scenarios. Specific technical capabilities must be developed before star tracker only sch...

  3. Performance of the Microwave Anisotropy Probe AST-201 Star Trackers

    Science.gov (United States)

    Ward, David K.; vanBezooijen, Roelof; Bauer, Frank H. (Technical Monitor)

    2002-01-01

    The Microwave Anisotropy Probe (MAP) was launched to create a full-sky map of the cosmic microwave background. MAP incorporates two modified Lockheed Martin AST-201 (Autonomous Star Tracker) star trackers. The AST-201 employs an eight element radiation hardened lens assembly which is used to focus an image on a charge coupled device (CCD). The CCD image is then processed by a star identification algorithm which outputs a three-axis attitude. A CCD-shift algorithm called Time Delayed Integration (TDI) was also included in each star tracker. In order to provide some radiation effect filtering during MAP's three to five phasing loop passes through the Van Allen radiation belts, a simple pixel filtering scheme was implemented, rather than using a more complex, but more robust windowing algorithm. The trackers also include a fiber optic data interface. This paper details the ground testing that was accomplished on the MAP trackers.

  4. Star-Tracker Computer Program

    Science.gov (United States)

    Glavich, Thomas

    1987-01-01

    Image-analyzing pointing systems aimed to high precision. Star-tracker program, STRACKER, developed to solve algorithm-design problems for area-array tracking and pointing systems operating at accuracies of 0.001 to 0.01 picture element. Includes auxiliary programs for reformatting point-spread data from commercial ACCOSV lens-design program. Other optical-analysis program data reformatted by use of utility routines included in package. Written in FORTRAN 77.

  5. Development and Implementation of Star Tracker Electronics

    OpenAIRE

    Lindh, Marcus

    2014-01-01

    Star trackers are essential instruments commonly used on satellites. They provide precise measurement of the orientation of a satellite and are part of the attitude control system. For cubesats star trackers need to be small, consume low power and preferably cheap to manufacture. In this thesis work the electronics for a miniature star tracker has been developed. A star detection algorithm has been implemented in hardware logic, tested and verified. A platform for continued work is presented ...

  6. Star tracker for the Apollo telescope mount

    Science.gov (United States)

    Lee, C. E.

    1971-01-01

    The star tracker for the Apollo Telescope Mount (ATM) has been designed specifically to meet the requirements of the Skylab vehicle and mission. The functions of the star tracker are presented, as well as descriptions of the optical-mechanical assembly (OMA) and the star tracker electronics (STE). Also included are the electronic and mechanical specifications, interface and operational requirements, support equipment and test requirements, and occultation information. Laboratory functional tests, environmental qualification tests, and life tests have provided a high confidence factor in the performance of the star tracker in the laboratory and on the Skylab mission.

  7. Star Position Estimation Improvements for Accurate Star Tracker Attitude Estimation

    OpenAIRE

    Delabie, Tjorven

    2015-01-01

    This paper presents several methods to improve the estimation of the star positions in a star tracker, using a Kalman Filter. The accuracy with which the star positions can be estimated greatly influences the accuracy of the star tracker attitude estimate. In this paper, a Kalman Filter with low computational complexity, that can be used to estimate the star positions based on star tracker centroiding data and gyroscope data is discussed. The performance of this Kalman Filter can be increased...

  8. Precession–nutation correction for star tracker attitude measurement of STECE satellite

    OpenAIRE

    Lai Yuwang; Liu Junhong; Ding Yonghe; Gu Defeng; Yi Dongyun

    2014-01-01

    Space Technology Experiment and Climate Exploration (STECE) is a small satellite mission of China for space technology experiment and climate exploration. A new test star tracker and one ASTRO 10 star tracker have been loaded on the STECE satellite to test the new star tracker’s measurement performance. However, there is no autonomous precession–nutation correction function for the test star tracker, which causes an apparent periodic deflection in the inter-boresight angle between the two sta...

  9. Rosetta Star Tracker and Navigation Camera

    DEFF Research Database (Denmark)

    Thuesen, Gøsta

    1998-01-01

    Proposal in response to the Invitation to Tender (ITT) issued by Matra Marconi Space (MSS) for the procurement of the ROSETTA Star Tracker and Navigation Camera.......Proposal in response to the Invitation to Tender (ITT) issued by Matra Marconi Space (MSS) for the procurement of the ROSETTA Star Tracker and Navigation Camera....

  10. A Heavy Flavor Tracker for STAR

    OpenAIRE

    Z. Xu; Chen, Y; Kleinfelder, S.; Koohi, A.; Li, S.; H. Huang; Tai, A.; Kushpil, V.; Sumbera, M; Colledani, C.; Dulinski, W.; Himmi, A.; Hu, C; Shabetai, A.; Szelezniak, M.

    2005-01-01

    We propose to construct a Heavy Flavor Tracker (HFT) for the STAR experiment at RHIC. The HFT will bring new physics capabilities to STAR and it will significantly enhance the physics capabilities of the STAR detector at central rapidities. The HFT will ensure that STAR will be able to take heavy flavor data at all luminosities attainable throughout the proposed RHIC II era.

  11. A Heavy Flavor Tracker for STAR

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Chen, Y.; Kleinfelder, S.; Koohi, A.; Li, S.; Huang, H.; Tai, A.; Kushpil, V.; Sumbera, M.; Colledani, C.; Dulinski, W.; Himmi,A.; Hu, C.; Shabetai, A.; Szelezniak, M.; Valin, I.; Winter, M.; Miller,M.; Surrow, B.; Van Nieuwenhuizen G.; Bieser, F.; Gareus, R.; Greiner,L.; Lesser, F.; Matis, H.S.; Oldenburg, M.; Ritter, H.G.; Pierpoint, L.; Retiere, F.; Rose, A.; Schweda, K.; Sichtermann, E.; Thomas, J.H.; Wieman, H.; Yamamoto, E.; Kotov, I.

    2005-03-14

    We propose to construct a Heavy Flavor Tracker (HFT) for theSTAR experiment at RHIC. The HFT will bring new physics capabilities toSTAR and it will significantly enhance the physics capabilities of theSTAR detector at central rapidities. The HFT will ensure that STAR willbe able to take heavy flavor data at all luminosities attainablethroughout the proposed RHIC II era.

  12. A Heavy Flavor Tracker for STAR

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Chen, Y.; Kleinfelder, S.; Koohi, A.; Li, S.; Huang, H.; Tai, A.; Kushpil, V.; Sumbera, M.; Colledani, C.; Dulinski, W.; Himmi,A.; Hu, C.; Shabetai, A.; Szelezniak, M.; Valin, I.; Winter, M.; Surrow,B.; Van Nieuwenhuizen, G.; Bieser, F.; Gareus, R.; Greiner, L.; Lesser,F.; Matis, H.S.; Oldenburg, M.; Ritter, H.G.; Pierpoint, L.; Retiere, F.; Rose, A.; Schweda, K.; Sichtermann, E.; Thomas, J.H.; Wieman, H.; Yamamoto, E.; Kotov, I.

    2005-03-14

    We propose to construct a Heavy Flavor Tracker (HFT) for the STAR experiment at RHIC. The HFT will bring new physics capabilities to STAR and it will significantly enhance the physics capabilities of the STAR detector at central rapidities. The HFT will ensure that STAR will be able to take heavy flavor data at all luminosities attainable throughout the proposed RHIC II era.

  13. Opportunity Science Using the Juno Magnetometer Investigation Star Trackers

    Science.gov (United States)

    Joergensen, J. L.; Connerney, J. E.; Bang, A. M.; Denver, T.; Oliversen, R. J.; Benn, M.; Lawton, P.

    2013-12-01

    The magnetometer experiment onboard Juno is equipped with four non-magnetic star tracker camera heads, two of which reside on each of the magnetometer sensor optical benches. These are located 10 and 12 m from the spacecraft body at the end of one of the three solar panel wings. The star tracker, collectively referred to as the Advanced Stellar Compass (ASC), provides high accuracy attitude information for the magnetometer sensors throughout science operations. The star tracker camera heads are pointed +/- 13 deg off the spin vector, in the anti-sun direction, imaging a 13 x 20 deg field of view every ¼ second as Juno rotates at 1 or 2 rpm. The ASC is a fully autonomous star tracker, producing a time series of attitude quaternions for each camera head, utilizing a suite of internal support functions. These include imaging capabilities, autonomous object tracking, automatic dark-sky monitoring, and related capabilities; these internal functions may be accessed via telecommand. During Juno's cruise phase, this capability can be tapped to provide unique science and engineering data available along the Juno trajectory. We present a few examples of the JUNO ASC opportunity science here. As the Juno spacecraft approached the Earth-Moon system for the close encounter with the Earth on October 9, 2013, one of the ASC camera heads obtained imagery of the Earth-Moon system while the other three remained in full science (attitude determination) operation. This enabled the first movie of the Earth and Moon obtained by a spacecraft flying past the Earth in gravity assist. We also use the many artificial satellites in orbit about the Earth as calibration targets for the autonomous asteroid detection system inherent to the ASC autonomous star tracker. We shall also profile the zodiacal dust disk, using the interstellar image data, and present the outlook for small asteroid body detection and distribution being performed during Juno's passage from Earth flyby to Jovian orbit

  14. A microprocessor-controlled CCD star tracker

    Science.gov (United States)

    Salomon, P. M.; Goss, W. C.

    1976-01-01

    The STELLAR (Star Tracker for Economical Long Life Attitude Reference) utilizes an image sensing Charge-Coupled Device (CCD) operating under microprocessor control. This approach results in a new type of high-accuracy star tracker which can be adapted to a wide variety of different space flight applications through software changes only. The STELLAR determines two-axis star positions by computing the element and the interelement interpolated centroid positions of the star images. As many as 10 stars may be tracked simultaneously, providing significantly increased stability and accuracy. A detailed description of the STELLAR is presented along with measurements of system performance obtained from an operating breadboard model.

  15. Combinations of 148 navigation stars and the star tracker

    Science.gov (United States)

    Duncan, R.

    1980-01-01

    The angular separation of all star combinations for 148 nav star on the onboard software for space transportation system-3 flight and following missions is presented as well as the separation of each pair that satisfies the viewing constraints of using both star trackers simultaneously. Tables show (1) shuttle star catalog 1980 star position in M 1950 coordinates; (2) two star combination of 148 nav stars; and (3) summary of two star-combinations of the star tracker 5 deg filter. These 148 stars present 10,875 combinations. For the star tracker filters of plus or minus 5 deg, there are 875 combinations. Formalhaut (nav star 26) has the best number of combinations, which is 33.

  16. Star Tracker Performance Estimate with IMU

    Science.gov (United States)

    Aretskin-Hariton, Eliot D.; Swank, Aaron J.

    2015-01-01

    A software tool for estimating cross-boresight error of a star tracker combined with an inertial measurement unit (IMU) was developed to support trade studies for the Integrated Radio and Optical Communication project (iROC) at the National Aeronautics and Space Administration Glenn Research Center. Typical laser communication systems, such as the Lunar Laser Communication Demonstration (LLCD) and the Laser Communication Relay Demonstration (LCRD), use a beacon to locate ground stations. iROC is investigating the use of beaconless precision laser pointing to enable laser communication at Mars orbits and beyond. Precision attitude knowledge is essential to the iROC mission to enable high-speed steering of the optical link. The preliminary concept to achieve this precision attitude knowledge is to use star trackers combined with an IMU. The Star Tracker Accuracy (STAcc) software was developed to rapidly assess the capabilities of star tracker and IMU configurations. STAcc determines the overall cross-boresight error of a star tracker with an IMU given the characteristic parameters: quantum efficiency, aperture, apparent star magnitude, exposure time, field of view, photon spread, detector pixels, spacecraft slew rate, maximum stars used for quaternion estimation, and IMU angular random walk. This paper discusses the supporting theory used to construct STAcc, verification of the program and sample results.

  17. Star spot location estimation using Kalman filter for star tracker.

    Science.gov (United States)

    Liu, Hai-bo; Yang, Jian-kun; Wang, Jiong-qi; Tan, Ji-chun; Li, Xiu-jian

    2011-04-20

    Star pattern recognition and attitude determination accuracy is highly dependent on star spot location accuracy for the star tracker. A star spot location estimation approach with the Kalman filter for a star tracker has been proposed, which consists of three steps. In the proposed approach, the approximate locations of the star spots in successive frames are predicted first; then the measurement star spot locations are achieved by defining a series of small windows around each predictive star spot location. Finally, the star spot locations are updated by the designed Kalman filter. To confirm the proposed star spot location estimation approach, the simulations based on the orbit data of the CHAMP satellite and the real guide star catalog are performed. The simulation results indicate that the proposed approach can filter out noises from the measurements remarkably if the sampling frequency is sufficient. PMID:21509065

  18. Optical contacting for gravity probe star tracker

    Science.gov (United States)

    Wright, J. J.; Zissa, D. E.

    1984-01-01

    A star-tracker telescope, constructed entirely of fused silica elements optically contacted together, has been proposed to provide submilliarc-second pointing accuracy for Gravity Probe. A bibliography and discussion on optical contacting (the bonding of very flat, highly polished surfaces without the use of adhesives) are presented. Then results from preliminary experiments on the strength of optical contacts including a tensile strength test in liquid helium are discussed. Suggestions are made for further study to verify an optical contacting method for the Gravity Probe star-tracker telescope.

  19. A Heavy Flavor Tracker for STAR

    OpenAIRE

    Chasman, C.

    2008-01-01

    The STAR Collaboration proposes to construct a state-of-the-art microvertex detector, the Heavy Flavor Tracker (HFT), utilizing active pixel sensors and silicon strip technology. The HFT will significantly extend the physics reach of the STAR experiment for precision measurement of the yields and spectra of particles containing heavy quarks. This will be accomplished through topological identification of D mesons by reconstruction of their displaced decay vertices with a precision of approxim...

  20. The STAR Heavy Flavor Tracker (HFT)

    OpenAIRE

    Schambach, Joachim; Anderssen, Eric; Wieman, Howard; Woodmansee, Sam; Contin, Giacomo; Greiner, Leo; Silber, Joe; Stezelberger, Thorsten; Sun, Xiangming; Szelezniak, Michal; Videbæk, Flemming; Vu, Chinh

    2014-01-01

    The heavy quark hadrons are suggested as a clean probe for studying the early dynamic evolution of the dense and hot medium created in high-energy nuclear collisions. The Heavy Flavor Tracker (HFT) of the STAR experiment, designed to improve the vertex resolution and extend the measurement capabilities in the heavy flavor domain, was installed for the 2014 heavy ion run of RHIC. It is composed of three different silicon detectors arranged in four concentric cylinders close to the STAR interac...

  1. RFP for the Auroral Multiscale Midex (AMM) Mission star tracker

    DEFF Research Database (Denmark)

    Riis, Troels; Betto, Maurizio; Jørgensen, John Leif;

    1999-01-01

    This document is in response to the John Hopkins University - Applied Physics Laboratory RFP for the Auroral Multiscale Midex Mission star tracker.It describes the functionality, the requirements and the performance of the ASC Star Tracker.......This document is in response to the John Hopkins University - Applied Physics Laboratory RFP for the Auroral Multiscale Midex Mission star tracker.It describes the functionality, the requirements and the performance of the ASC Star Tracker....

  2. Real-Time Hardware-in-the-Loop Tests of Star Tracker Algorithms

    OpenAIRE

    Giancarlo Rufino; Domenico Accardo; Michele Grassi; Giancarmine Fasano; Alfredo Renga; Urbano Tancredi

    2013-01-01

    This paper deals with star tracker algorithms validation based on star field scene simulation and hardware-in-the-loop test configuration. A laboratory facility for indoor tests, based on the simulation of star field scenes, is presented. Attainable performance is analyzed theoretically for both static and dynamic simulations. Also, a test campaign is presented, in which a star sensor prototype with real-time, fully autonomous capability is exploited. Results that assess star field scene simu...

  3. Precession–nutation correction for star tracker attitude measurement of STECE satellite

    Directory of Open Access Journals (Sweden)

    Lai Yuwang

    2014-02-01

    Full Text Available Space Technology Experiment and Climate Exploration (STECE is a small satellite mission of China for space technology experiment and climate exploration. A new test star tracker and one ASTRO 10 star tracker have been loaded on the STECE satellite to test the new star tracker’s measurement performance. However, there is no autonomous precession–nutation correction function for the test star tracker, which causes an apparent periodic deflection in the inter-boresight angle between the two star trackers with respect to each other of up to ±500 arcsec, so the precession and nutation effect needs to be considered while assessing the test star tracker. This paper researches on the precession–nutation correction for the test star tracker’s attitude measurement and presents a precession–nutation correction method based on attitude quaternion data. The periodic deflection of the inter-boresight angle between the two star trackers has been greatly eliminated after the precession and nutation of the test star tracker’s attitude data have been corrected by the proposed method and the validity of the proposed algorithm has been demonstrated. The in-flight accuracy of the test star tracker has been assessed like attitude noise and low-frequency errors after the precession–nutation correction.

  4. Precession-nutation correction for star tracker attitude measurement of STECE satellite

    Institute of Scientific and Technical Information of China (English)

    Lai Yuwang; Liu Junhong; Ding Yonghe; Gu Defeng; Yi Dongyun

    2014-01-01

    Space Technology Experiment and Climate Exploration (STECE) is a small satellite mis-sion of China for space technology experiment and climate exploration. A new test star tracker and one ASTRO 10 star tracker have been loaded on the STECE satellite to test the new star tracker’s measurement performance. However, there is no autonomous precession-nutation correction func-tion for the test star tracker, which causes an apparent periodic deflection in the inter-boresight angle between the two star trackers with respect to each other of up to ±500 arcsec, so the preces-sion and nutation effect needs to be considered while assessing the test star tracker. This paper researches on the precession-nutation correction for the test star tracker’s attitude measurement and presents a precession-nutation correction method based on attitude quaternion data. The peri-odic deflection of the inter-boresight angle between the two star trackers has been greatly eliminated after the precession and nutation of the test star tracker’s attitude data have been corrected by the proposed method and the validity of the proposed algorithm has been demonstrated. The in-flight accuracy of the test star tracker has been assessed like attitude noise and low-frequency errors after the precession-nutation correction.

  5. An Integrated Tracker for STAR

    OpenAIRE

    Simon, Frank; Collaboration, for the STAR

    2006-01-01

    The STAR experiment at the Relativistic Heavy Ion Collider RHIC studies the new state of matter produced in relativistic heavy ion collisions and the spin structure of the nucleon in collisions of polarized protons. In order to improve the capabilities for heavy flavor measurements and the reconstruction of charged vector bosons an upgrade of the tracking system both in the central and the forward region is pursued. The integrated system providing high resolution tracking and secondary vertex...

  6. An Integrated Tracker for STAR

    CERN Document Server

    Simon, F

    2006-01-01

    The STAR experiment at the Relativistic Heavy Ion Collider RHIC studies the new state of matter produced in relativistic heavy ion collisions and the spin structure of the nucleon in collisions of polarized protons. In order to improve the capabilities for heavy flavor measurements and the reconstruction of charged vector bosons an upgrade of the tracking system both in the central and the forward region is pursued. The integrated system providing high resolution tracking and secondary vertex reconstruction capabilities will use silicon pixel, strip and GEM technology.

  7. Precision Pointing Control System (PPCS) star tracker test

    Science.gov (United States)

    1972-01-01

    Tests performed on the TRW precision star tracker are described. The unit tested was a two-axis gimballed star tracker designed to provide star LOS data to an accuracy of 1 to 2 sec. The tracker features a unique bearing system and utilizes thermal and mechanical symmetry techniques to achieve high precision which can be demonstrated in a one g environment. The test program included a laboratory evaluation of tracker functional operation, sensitivity, repeatibility, and thermal stability.

  8. Microsatellite Star Tracker Baffles: Validation and Testing

    OpenAIRE

    Marciniak, Martin; Enright, John; Sinclair, Doug; Dzamba, Tom

    2013-01-01

    In this paper, we examine the challenges of ground-based stray light testing from a microsatellite perspective. We consider some of the historical approaches to simulation and laboratory testing and propose strategies for ground validation that require only modest investment in test facilities. The star tracker or instrument is characterized in the lab without any baffle, using a novel technique to subtract out reflections internal to the test chamber. From the resulting data a simulation ele...

  9. Star Tracker Cost Reduction for Small Satellites

    OpenAIRE

    Delabie, Tjorven; DE SCHUTTER, JORIS; Vandenbussche, Bart

    2014-01-01

    In recent years, the great potential of small satellites has become ever clearer and small satellites are selected to perform increasingly complex missions. With this rise in mission complexity, the requirements on the Attitude Determination and Control System of the satellite increase as well. Of all the attitude determination sensors, the star tracker is by far the most accurate one. The accuracy of this sensor is in the order of arc seconds. The disadvantages of this sensor are that it...

  10. Lightweight, Low-Power Coarse Star Tracker

    OpenAIRE

    Zenick, Ray; McGuire, Thomas

    2003-01-01

    General industry research on spacecraft attitude determination and control components is focused on increasing accuracy to the exclusion of all else. This is contrary to the clear requirement for decreased complexity, mass, and power consumption to fit the needs of small, maneuverable, low-cost spacecraft. To address this need, AeroAstro and the Massachusetts Institute of Technology Space Systems Laboratory are developing a coarse star tracker, which strikes an appropriate balance between acc...

  11. A Heavy-Flavor Tracker for STAR

    CERN Document Server

    Schweda, K

    2006-01-01

    We propose to construct a heavy flavor tracker for the STAR experiment at RHIC in order to measure the elliptic flow of charmed hadrons in the low pt region and identify B-meson contributions in the region pt > 4 GeV/c. In this talk, we will present the design of the detector in-depth and its expected performance as studied in detailed simulations and analytic calculations. Physics potentials of the detector will also be discussed.

  12. A Brightness-Referenced Star Identification Algorithm for APS Star Trackers

    OpenAIRE

    Peng Zhang; Qile Zhao; Jingnan Liu; Ning Liu

    2014-01-01

    Star trackers are currently the most accurate spacecraft attitude sensors. As a result, they are widely used in remote sensing satellites. Since traditional charge-coupled device (CCD)-based star trackers have a limited sensitivity range and dynamic range, the matching process for a star tracker is typically not very sensitive to star brightness. For active pixel sensor (APS) star trackers, the intensity of an imaged star is valuable information that can be used in star identification process...

  13. Autonomous orientation for LEO spacecraft using multi-FOV star tracker%多视场星敏感器近地轨道自主定位导航方法

    Institute of Scientific and Technical Information of China (English)

    魏新国; 李延鹏; 李健; 江洁

    2014-01-01

    传统航天器自主天文导航需要星敏感器、红外地平仪、磁强计等多种敏感器采集导航数据,增加了航天器的成本和复杂度。利用多视场星敏感器的特点,分别对恒星与地球进行成像,在完成姿态测量的同时,得到地心矢量信息,从而进行自主天文导航。首先建立地球几何模型,结合航天器轨道参数与多视场星敏感器的安装布局,实现各个视场内地球边缘的成像模拟,使用Steger算法提取地球边缘。综合考虑地球扁率的影响,对不同视场中观测到的地球边缘进行拟合得到精确地心矢量,最后进行基于星光角距的直接敏感地平导航仿真。仿真结果表明,在一个视场观测恒星,另外两个视场观测地球边缘的布局情况下,地心矢量精度和导航位置精度分别达到0.0172º(1σ)和190 m(1σ)。%The traditional methods for spacecraft autonomous navigation need several sensors, such as star sensor, infrared horizon sensor and magnetometer, to collect navigation data. As a result the load of spacecraft will gain in weight, size and power. Based on the advantages of multi- field of view (FOV) star tracker, an autonomous navigation method was proposed which used multi- FOV star tracker (MFST) to image the star and the earth respectively and got the orientation vectors of them. Combining with the orbit parameters of the spacecraft and the layout of the MFST, a mathematic model of the earth imaging was set up to implement the earth edge images in every single FOV. The Steger method was used to determine the earth edge in the images. Considering the earth oblateness, the orientation vector of the earth will be obtained through circle- fitting the earth edge points in each FOV. With the configuration that one FOV measures the navigation star and the other two FOV measures the earth edge, the autonomous orientation based on the starlight angle is simulated and the result indicates that

  14. Attitude determination using Star Tracker Data with Kalman filters

    OpenAIRE

    Travis, Henry D.

    2001-01-01

    This study adapts some established attitude determination techniq ues for use with star tracker measurements on satellites. Other work in this area has utilized gyro measurements with star tracker updates. Todayαs star trackers are giving measurements with accuracies of less than 6 arcseconds, and are therefore of high enough fidelity to be used alone. Computer simulation of a Linear Kalman Filter to process these measurements is presented. The Filter uses a linear, constant coefficient stat...

  15. Exposure Time Optimization for Highly Dynamic Star Trackers

    OpenAIRE

    Xinguo Wei; Wei Tan; Jian Li; Guangjun Zhang

    2014-01-01

    Under highly dynamic conditions, the star-spots on the image sensor of a star tracker move across many pixels during the exposure time, which will reduce star detection sensitivity and increase star location errors. However, this kind of effect can be compensated well by setting an appropriate exposure time. This paper focuses on how exposure time affects the star tracker under highly dynamic conditions and how to determine the most appropriate exposure time for this case. Firstly, the effect...

  16. A Heavy Flavor Tracker for STAR

    Energy Technology Data Exchange (ETDEWEB)

    Chasman, C.; Beavis, D.; Debbe, R.; Lee, J.H.; Levine, M.J.; Videbaek, F.; Xu, Z.; Kleinfelder, S.; Li, S.; Cendejas, R.; Huang, H.; Sakai, S.; Whitten, C.; Joseph, J.; Keane, D.; Margetis, S.; Rykov, V.; Zhang, W.M.; Bystersky, M.; Kapitan, J.; Kushpil, V.; Sumbera, M.; Baudot, J.; Hu-Guo, C.; Shabetai, A.; Szelezniak, M.; Winter, M.; Kelsey, J.; Milner, R.; Plesko, M.; Redwine, R.; Simon, F.; Surrow, B.; Van Nieuwenhuizen, G.; Anderssen, E.; Dong, X.; Greiner, L.; Matis, H.S.; Morgan, S.; Ritter, H.G.; Rose, A.; Sichtermann, E.; Singh, R.P.; Stezelberger, T.; Sun, X.; Thomas, J.H.; Tram, V.; Vu, C.; Wieman, H.H.; Xu, N.; Hirsch, A.; Srivastava, B.; Wang, F.; Xie, W.; Bichsel, H.

    2008-02-25

    The STAR Collaboration proposes to construct a state-of-the-art microvertex detector,the Heavy Flavor Tracker (HFT), utilizing active pixel sensors and silicon strip technology. The HFT will significantly extend the physics reach of the STAR experiment for precision measurement of the yields and spectra of particles containing heavy quarks. This will be accomplished through topological identification of D mesons by reconstruction of their displaced decay vertices with a precision of approximately 50 mu m in p+p, d+A, and A+A collisions. The HFT consists of 4 layers of silicon detectors grouped into two sub-systems with different technologies, guaranteeing increasing resolution when tracking from the TPC and the Silicon Strip Detector (SSD) towards the vertex of the collision. The Intermediate Silicon Tracker (IST), consisting of two layers of single-sided strips, is located inside the SSD. Two layers of Silicon Pixel Detector (PIXEL) are inside the IST. The PIXEL detectors have the resolution necessary for a precision measurement of the displaced vertex. The PIXEL detector will use CMOS Active Pixel Sensors (APS), an innovative technology never used before in a collider experiment. The APSsensors are only 50 mu m thick and at a distance of only 2.5 cm from the interaction point. This opens up a new realm of possibilities for physics measurements. In particular, a thin detector (0.28percent radiation length per layer) in STAR makes it possible to do the direct topological reconstruction of open charm hadrons down to very low pT by the identification of the charged daughters of the hadronic decay.

  17. Star tracker and vision systems performance in a high radiation environment

    OpenAIRE

    Jørgensen, John Leif; Riis, Troels; Betto, Maurizio

    1999-01-01

    A part of the payload of the second Ariane 5 prototype vehicle to be launched by Arianespace, was a small technology demonstration satellite. On October 30th, 1997, this test satellite, dubbed Teamsat, was launched into Geostationary Transfer Orbit and would as such pass the Van Allen radiation belts twice per orbit. One of the experiments onboard Teamsat was the so-called Autonomous Vision System (AVS). The AVS instrument is a fully autonomous star tracker with several advanced features for ...

  18. Documentation for delivery of Star Tracker to PROBA

    DEFF Research Database (Denmark)

    Thuesen, Gøsta; Riis, Troels; Madsen, Peter Buch;

    1999-01-01

    The documentation EIDP (End Item Data Package) describes all the tests which have been performed on the flight hardware of the Star Tracker for the ESA satellite PROBA.......The documentation EIDP (End Item Data Package) describes all the tests which have been performed on the flight hardware of the Star Tracker for the ESA satellite PROBA....

  19. Documentation for delivery of Star Tracker to ADEOS II

    DEFF Research Database (Denmark)

    Madsen, Peter Buch; Betto, Maurizio; Denver, Troelz;

    1999-01-01

    The documentation EIDP (End Item Data Package) describes all the tests which have been performed on the Flight Hardware of the Star Tracker for the Japanese satellite ADEOS II.......The documentation EIDP (End Item Data Package) describes all the tests which have been performed on the Flight Hardware of the Star Tracker for the Japanese satellite ADEOS II....

  20. Documentation for delivery of Star Tracker to CHAMP

    DEFF Research Database (Denmark)

    Madsen, Peter Buch; Betto, Maurizio; Jørgensen, John Leif;

    1999-01-01

    The documentation EIDP (End Item Data Package) describes all the tests which have been performed on the flight hardware of the Star Tracker for the German satellite CHAMP.......The documentation EIDP (End Item Data Package) describes all the tests which have been performed on the flight hardware of the Star Tracker for the German satellite CHAMP....

  1. Forward GEM Tracker (FGT) at STAR

    Science.gov (United States)

    Surrow, Bernd

    2012-10-01

    As part of our program to understand the internal structure of the proton, we have and will continue mid-rapidity (-1anti-d quarks to the proton spin. The gluon spin contribution can be probed through di-jet measurements. The Forward GEM Tracker (FGT) at STAR will enhance the charged sign separation for high pT tracks in the pseudo-rapidity range of 1.0<η<2.0, and therefore allows an extension of W and di-jet measurements at forward pseudo-rapidity. We will present the status of the FGT assembly and completion along with projections for future W and di-jet measurements. We will discuss studies that explore the possibilities of using the FGT to reconstruct jets in the forward direction.

  2. A low-cost, CCD solid state star tracker

    Science.gov (United States)

    Chmielowski, M.; Wynne, D.

    1992-01-01

    Applied Research Corporation (ARC) has developed an engineering model of a multi-star CCD-based tracker for space applications requiring radiation hardness, high reliability and low power consumption. The engineering unit compared favorably in functional performance tests to the standard NASA single-star tracker. Characteristics of the ARC star tracker are: field of view = 10 deg x 7.5 deg, sensitivity range of -1 to +5 star magnitude, NEA = 3 in x 3 in, linearity = 5 in x 5 in, and power consumption of 1-3 W (operating mode dependent). The software is upgradable through a remote link. The hardware-limited acquisition rate is 1-5 Hz for stars of +2 to +5 magnitude and 10-30 Hz for -1 to +2 magnitude stars. Mechanical and electrical interfaces are identical to the standard NASA star tracker.

  3. Optimization of star research algorithm for esmo star tracker

    OpenAIRE

    Jalabert, Eva; Fabacher, Emilien; Guy, Nicolas; Lizy-Destrez, Stéphanie; Rappin, William; Rivier, Guillaume

    2011-01-01

    This paper explains in detail the design and the development of a software research star algorithm, embedded on a star tracker, by the ISAE/SUPAERO team. This research algorithm is inspired by musical techniques. This work will be carried out as part of the ESMO (European Student Moon Orbiter) project by different teams of students and professors from ISAE/SUPAERO (Institut Supe ́rieur de l’Ae ́ronautique et de l’Espace). Till today, the system engineering studies have been completed and the ...

  4. High Energy Astronomy Observatory star tracker search program

    Science.gov (United States)

    Weiler, W. J.

    1972-01-01

    The development of a control system to accommodate the scientific payload of the High Energy Astronomy Observatory (HEAO) is discussed. One of the critical elements of the system is the star tracker subsystem, which defines an accurate three-axis attitude reference. A digital computer program has been developed to evaluate the ability of a particular star tracker configuration to meet the requirements for attitude reference at various vehicle orientations. Used in conjuction with an adequate star catalog, the computer program provides information on availability of stars for each tracker and on the ability of the system to maintain three-axis attitude reference throughout a representative sequence of vehicle orientations.

  5. Exposure time optimization for highly dynamic star trackers.

    Science.gov (United States)

    Wei, Xinguo; Tan, Wei; Li, Jian; Zhang, Guangjun

    2014-01-01

    Under highly dynamic conditions, the star-spots on the image sensor of a star tracker move across many pixels during the exposure time, which will reduce star detection sensitivity and increase star location errors. However, this kind of effect can be compensated well by setting an appropriate exposure time. This paper focuses on how exposure time affects the star tracker under highly dynamic conditions and how to determine the most appropriate exposure time for this case. Firstly, the effect of exposure time on star detection sensitivity is analyzed by establishing the dynamic star-spot imaging model. Then the star location error is deduced based on the error analysis of the sub-pixel centroiding algorithm. Combining these analyses, the effect of exposure time on attitude accuracy is finally determined. Some simulations are carried out to validate these effects, and the results show that there are different optimal exposure times for different angular velocities of a star tracker with a given configuration. In addition, the results of night sky experiments using a real star tracker agree with the simulation results. The summarized regularities in this paper should prove helpful in the system design and dynamic performance evaluation of the highly dynamic star trackers. PMID:24618776

  6. Exposure Time Optimization for Highly Dynamic Star Trackers

    Directory of Open Access Journals (Sweden)

    Xinguo Wei

    2014-03-01

    Full Text Available Under highly dynamic conditions, the star-spots on the image sensor of a star tracker move across many pixels during the exposure time, which will reduce star detection sensitivity and increase star location errors. However, this kind of effect can be compensated well by setting an appropriate exposure time. This paper focuses on how exposure time affects the star tracker under highly dynamic conditions and how to determine the most appropriate exposure time for this case. Firstly, the effect of exposure time on star detection sensitivity is analyzed by establishing the dynamic star-spot imaging model. Then the star location error is deduced based on the error analysis of the sub-pixel centroiding algorithm. Combining these analyses, the effect of exposure time on attitude accuracy is finally determined. Some simulations are carried out to validate these effects, and the results show that there are different optimal exposure times for different angular velocities of a star tracker with a given configuration. In addition, the results of night sky experiments using a real star tracker agree with the simulation results. The summarized regularities in this paper should prove helpful in the system design and dynamic performance evaluation of the highly dynamic star trackers.

  7. On Random and Systematic Errors of a Star Tracker

    OpenAIRE

    Tuchin, Maksim; Biryukov, Anton; Nickiforov, Mikhail; Prokhorov, Mikhail; Zakharov, Andrey

    2013-01-01

    The error of the attitude of many modern star trackers is determined by systematic errors. In this paper we consider the effect of random and different systematic errors of sensors on the attitude accuracy of star trackers. The results of modeling of principal systematic errors, first of all, due to underestimation of the dark current inhomogeneity, are discussed. It is shown that only this systematic error can decrease the attitude accuracy of a star tracker by a factor of 3–4. Methods of ta...

  8. EOS attitude determination and next generation star tracker enhancements

    Science.gov (United States)

    Kudva, P.; Throckmorton, A.

    1993-01-01

    The pointing knowledge required for the Earth Observing System (EOS) AM mission is at the limit of the current generation of star trackers, with little margin. Techniques for improving the performance of existing star trackers are explored, with performance sensitivities developed for each alternative. These are extended to define the most significant performance enhancements for a next generation star tracker. Since attitude determination studies tend to be computationally intensive, an approach for using a simpler one degree of freedom formulation is contrasted with a full three degree of freedom formulation. Additionally, covariance analysis results are compared with time domain simulation performance results.

  9. Simulation analysis of dynamic working performance for star trackers.

    Science.gov (United States)

    Shen, Juan; Zhang, Guangjun; Wei, Xinguo

    2010-12-01

    The elongated imaging track pertaining to a star spot recorded in the image sensor of a star tracker will diffuse over several pixels at a high angular velocity, leading to an inaccurate, even false, attitude value. A computer simulation of the attitude determination from a dynamic star tracker is developed first, based on a dynamic mathematical model of the star-spot imaging and an efficiency validation of the star centroiding algorithm in the dynamic condition. Then major error sources affecting the attitude accuracy in the dynamic condition are analyzed and discussed systematically based on the simulation results. A mathematical model calculating the average star number detected in the field of view is also deduced, using simulation results and signal processing theory, with image trailing ranging from 0 to 20 pixels during exposure. The summarized regularity is helpful in the system design and accuracy evaluation of a star tracker. PMID:21119749

  10. Lost in space: Onboard star identification using CCD star tracker data without an a priori attitude

    Science.gov (United States)

    Ketchum, Eleanor A.; Tolson, Robert H.

    1993-01-01

    There are many algorithms in use today which determine spacecraft attitude by identifying stars in the field of view of a star tracker. Some methods, which date from the early 1960's, compare the angular separation between observed stars with a small catalog. In the last 10 years, several methods have been developed which speed up the process and reduce the amount of memory needed, a key element to onboard attitude determination. However, each of these methods require some a priori knowledge of the spacecraft attitude. Although the Sun and magnetic field generally provide the necessary coarse attitude information, there are occasions when a spacecraft could get lost when it is not prudent to wait for sunlight. Also, the possibility of efficient attitude determination using only the highly accurate CCD star tracker could lead to fully autonomous spacecraft attitude determination. The need for redundant coarse sensors could thus be eliminated at substantial cost reduction. Some groups have extended their algorithms to implement a computation intense full sky scan. Some require large data bases. Both storage and speed are concerns for autonomous onboard systems. Neural network technology is even being explored by some as a possible solution, but because of the limited number of patterns that can be stored and large overhead, nothing concrete has resulted from these efforts. This paper presents an algorithm which, by descretizing the sky and filtering by visual magnitude of the brightness observed star, speeds up the lost in space star identification process while reducing the amount of necessary onboard computer storage compared to existing techniques.

  11. Gaussian Analytic Centroiding method of star image of star tracker

    Science.gov (United States)

    Wang, Haiyong; Xu, Ershuai; Li, Zhifeng; Li, Jingjin; Qin, Tianmu

    2015-11-01

    The energy distribution of an actual star image coincides with the Gaussian law statistically in most cases, so the optimized processing algorithm about star image centroiding should be constructed also by following Gaussian law. For a star image spot covering a certain number of pixels, the marginal distribution of the gray accumulation on rows and columns are shown and analyzed, based on which the formulas of Gaussian Analytic Centroiding method (GAC) are deduced, and the robustness is also promoted due to the inherited filtering effect of gray accumulation. Ideal reference star images are simulated by the PSF (point spread function) with integral form. Precision and speed tests for the Gaussian Analytic formulas are conducted under three scenarios of Gaussian radius (0.5, 0.671, 0.8 pixel), The simulation results show that the precision of GAC method is better than that of the other given algorithms when the Gaussian radius is not bigger than 5 × 5 pixel window, a widely used parameter. Above all, the algorithm which consumes the least time is still the novel GAC method. GAC method helps to promote the comprehensive performance in the attitude determination of a star tracker.

  12. Interferometric Star Tracker for High Precision Pointing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Optical Physics Company (OPC) proposes to adapt the precision star tracker it is currently developing under several DoD contracts for deep space lasercom beam...

  13. Documentation for delivery of Star Tracker to SAC-C

    DEFF Research Database (Denmark)

    Kilsgaard, Søren; Thuesen, Gøsta; Riis, Troels;

    1999-01-01

    The documentation EIDP (End Item Data Package) describes all the tests which have been performed on the flight hardware of the Star Tracker for the Argentine, Danish and NASA satellite SAC-C.......The documentation EIDP (End Item Data Package) describes all the tests which have been performed on the flight hardware of the Star Tracker for the Argentine, Danish and NASA satellite SAC-C....

  14. Optical Alignment of the Global Precipitation Measurement (GPM) Star Trackers

    Science.gov (United States)

    Hetherington, Samuel; Osgood, Dean; McMann, Joe; Roberts, Viki; Gill, James; Mclean, Kyle

    2013-01-01

    The optical alignment of the star trackers on the Global Precipitation Measurement (GPM) core spacecraft at NASA Goddard Space Flight Center (GSFC) was challenging due to the layout and structural design of the GPM Lower Bus Structure (LBS) in which the star trackers are mounted as well as the presence of the star tracker shades that blocked line-of-sight to the primary star tracker optical references. The initial solution was to negotiate minor changes in the original LBS design to allow for the installation of a removable item of ground support equipment (GSE) that could be installed whenever measurements of the star tracker optical references were needed. However, this GSE could only be used to measure secondary optical reference cube faces not used by the star tracker vendor to obtain the relationship information and matrix transformations necessary to determine star tracker alignment. Unfortunately, due to unexpectedly large orthogonality errors between the measured secondary adjacent cube faces and the lack of cube calibration data, we required a method that could be used to measure the same reference cube faces as originally measured by the vendor. We describe an alternative technique to theodolite auto-collimation for measurement of an optical reference mirror pointing direction when normal incidence measurements are not possible. This technique was used to successfully align the GPM star trackers and has been used on a number of other NASA flight projects. We also discuss alignment theory as well as a GSFC-developed theodolite data analysis package used to analyze angular metrology data.

  15. Real-Time Hardware-in-the-Loop Tests of Star Tracker Algorithms

    Directory of Open Access Journals (Sweden)

    Giancarlo Rufino

    2013-01-01

    Full Text Available This paper deals with star tracker algorithms validation based on star field scene simulation and hardware-in-the-loop test configuration. A laboratory facility for indoor tests, based on the simulation of star field scenes, is presented. Attainable performance is analyzed theoretically for both static and dynamic simulations. Also, a test campaign is presented, in which a star sensor prototype with real-time, fully autonomous capability is exploited. Results that assess star field scene simulation performance and show the achievable validation for the sensor algorithms and performance in different operating modes (autonomous attitude acquisition, attitude tracking, and angular rate-only and different aspects (coverage, reliability, and measurement performance are discussed.

  16. On-Orbit Solar Dynamics Observatory (SDO) Star Tracker Warm Pixel Analysis

    Science.gov (United States)

    Felikson, Denis; Ekinci, Matthew; Hashmall, Joseph A.; Vess, Melissa

    2011-01-01

    This paper describes the process of identification and analysis of warm pixels in two autonomous star trackers on the Solar Dynamics Observatory (SDO) mission. A brief description of the mission orbit and attitude regimes is discussed and pertinent star tracker hardware specifications are given. Warm pixels are defined and the Quality Index parameter is introduced, which can be explained qualitatively as a manifestation of a possible warm pixel event. A description of the algorithm used to identify warm pixel candidates is given. Finally, analysis of dumps of on-orbit star tracker charge coupled devices (CCD) images is presented and an operational plan going forward is discussed. SDO, launched on February 11, 2010, is operated from the NASA Goddard Space Flight Center (GSFC). SDO is in a geosynchronous orbit with a 28.5 inclination. The nominal mission attitude points the spacecraft X-axis at the Sun, with the spacecraft Z-axis roughly aligned with the Solar North Pole. The spacecraft Y-axis completes the triad. In attitude, SDO moves approximately 0.04 per hour, mostly about the spacecraft Z-axis. The SDO star trackers, manufactured by Galileo Avionica, project the images of stars in their 16.4deg x 16.4deg fields-of-view onto CCD detectors consisting of 512 x 512 pixels. The trackers autonomously identify the star patterns and provide an attitude estimate. Each unit is able to track up to 9 stars. Additionally, each tracker calculates a parameter called the Quality Index, which is a measure of the quality of the attitude solution. Each pixel in the CCD measures the intensity of light and a warns pixel is defined as having a measurement consistently and significantly higher than the mean background intensity level. A warns pixel should also have lower intensity than a pixel containing a star image and will not move across the field of view as the attitude changes (as would a dim star image). It should be noted that the maximum error introduced in the star tracker

  17. A star identification algorithm based on a voting scheme for star trackers

    OpenAIRE

    M. Hamidi; F. Samadzadegan

    2014-01-01

    Star identification is one of the most important stages in attitude determination with star trackers. This can be performed using matching algorithms between observed stars and a master star catalogue. The main challenge in this approach is to provide a fast and reliable identification algorithm that is sufficiently robust in different pointing views of the star tracker optical system in the space. In this article, an identification algorithm based on a geometric voting scheme is presented. I...

  18. Multi-functional star tracker — future perspectives

    OpenAIRE

    J. Roháč; M. Řeřábek; R. Hudec(Czech Technical University in Prague, Faculty of electrical Engineering and Astronomical Institute, Academy of Science of the Czech Republic, Czech Republic)

    2011-01-01

    This paper focuses on the idea of a multi-functional wide-field star tracker (WFST) and provides a description of the current state-of-the-art in this field. The idea comes from a proposal handed in to ESA at the beginning of 2011. Star trackers (STs) usually have more than one object-lens with a small Field-of-View. They provide very precise information about the attitude in space according to consecutive evaluation of star positions. Our idea of WFST will combine the functions of several in...

  19. Improving the measurement quality of small satellite star trackers

    Science.gov (United States)

    Dzamba, Tom

    Recent demand from the small satellite community has led to the development of a new series of star trackers that are specifically designed for small satellites. These units represent substantial improvements in mass, power consumption and cost over traditional star trackers, but suffer slightly in terms of accuracy and availability performance. The primary factors inhibiting their performance are the use of significantly smaller optics, and commercial off the shelf components (COTS). This thesis presents a series of strategies for improving the performance of small satellite star trackers (SSSTs). These goals are realized through the development of offline calibration procedures, flight software, validation tests, and optical trade studies to guide future development. This thesis begins with the development of a target-based focusing procedure that enables precision control over the focus of the sensor optics. This improves the detection performance for dim stars, and ultimately increases the availability of the attitude solution. Flight software is developed to compensate for the effects of electronic rolling shutters, which reside on most COTS image detectors. Combined with a developed camera calibration procedure, these tools reduce the uncertainty with which a star tracker can measure the direction vectors to stars in view, ultimately increasing sensor accuracy. Integrated tests are performed to validate detection performance in dynamic conditions. These tests specifically examine the effect of slew rate on star tracker detection, and availability performance. Lastly, this thesis presents a series of optical trades studies that seek to identify design requirements for high performance SSSTs. The trends in availability and accuracy performance are examined as a function of different lens/detector configurations as well dual/triple-head sensor configurations. Together, these strategies represent tools that aim to improve small satellite star tracker performance

  20. Space shuttle orbiter vehicle star tracker test program plan

    Science.gov (United States)

    Smith, R. A.

    1974-01-01

    The development model test program was written to provide guidance for essential star tracker test support to the Space Shuttle Orbiter Program. The program organization included test equipment preparation, prototype baseline/acceptance tests, prototype total performance tests, and prototype special tests. Test configurations, preparation phase, documentation, scheduling, and manpower requirements are discussed. The test program permits an early evaluation of the tracker's performance prior to completion and testing of the final flight models.

  1. A Novel Gyro-less Tracking Method for Star Tracker

    OpenAIRE

    Mehdi Nasiri-Sarvi*1

    2014-01-01

    In this paper a new tracking method is presented, which is one of the most important and useful algorithms in the stat tracker normal mode. the developed algorithm is gyro less algorithm without need to angular speed information of satellite. The presented algorithm was realized and tested on the fabricated star tracker (ROJA1) in Nanoptronics research center located at faculty of electrical engineering, Iran University of Science and Technology.

  2. A brightness-referenced star identification algorithm for APS star trackers.

    Science.gov (United States)

    Zhang, Peng; Zhao, Qile; Liu, Jingnan; Liu, Ning

    2014-01-01

    Star trackers are currently the most accurate spacecraft attitude sensors. As a result, they are widely used in remote sensing satellites. Since traditional charge-coupled device (CCD)-based star trackers have a limited sensitivity range and dynamic range, the matching process for a star tracker is typically not very sensitive to star brightness. For active pixel sensor (APS) star trackers, the intensity of an imaged star is valuable information that can be used in star identification process. In this paper an improved brightness referenced star identification algorithm is presented. This algorithm utilizes the k-vector search theory and adds imaged stars' intensities to narrow the search scope and therefore increase the efficiency of the matching process. Based on different imaging conditions (slew, bright bodies, etc.) the developed matching algorithm operates in one of two identification modes: a three-star mode, and a four-star mode. If the reference bright stars (the stars brighter than three magnitude) show up, the algorithm runs the three-star mode and efficiency is further improved. The proposed method was compared with other two distinctive methods the pyramid and geometric voting methods. All three methods were tested with simulation data and actual in orbit data from the APS star tracker of ZY-3. Using a catalog composed of 1500 stars, the results show that without false stars the efficiency of this new method is 4~5 times that of the pyramid method and 35~37 times that of the geometric method. PMID:25299950

  3. System and method for calibrating inter-star-tracker misalignments in a stellar inertial attitude determination system

    Science.gov (United States)

    Li, Rongsheng (Inventor); Wu, Yeong-Wei Andy (Inventor); Hein, Douglas H. (Inventor)

    2004-01-01

    A method and apparatus for determining star tracker misalignments is disclosed. The method comprises the steps of defining a defining a reference frame for the star tracker assembly according to a boresight of the primary star tracker and a boresight of a second star tracker wherein the boresight of the primary star tracker and a plane spanned by the boresight of the primary star tracker and the boresight of the second star tracker at least partially define a datum for the reference frame for the star tracker assembly; and determining the misalignment of the at least one star tracker as a rotation of the defined reference frame.

  4. A Brightness-Referenced Star Identification Algorithm for APS Star Trackers

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2014-10-01

    Full Text Available Star trackers are currently the most accurate spacecraft attitude sensors. As a result, they are widely used in remote sensing satellites. Since traditional charge-coupled device (CCD-based star trackers have a limited sensitivity range and dynamic range, the matching process for a star tracker is typically not very sensitive to star brightness. For active pixel sensor (APS star trackers, the intensity of an imaged star is valuable information that can be used in star identification process. In this paper an improved brightness referenced star identification algorithm is presented. This algorithm utilizes the k-vector search theory and adds imaged stars’ intensities to narrow the search scope and therefore increase the efficiency of the matching process. Based on different imaging conditions (slew, bright bodies, etc. the developed matching algorithm operates in one of two identification modes: a three-star mode, and a four-star mode. If the reference bright stars (the stars brighter than three magnitude show up, the algorithm runs the three-star mode and efficiency is further improved. The proposed method was compared with other two distinctive methods the pyramid and geometric voting methods. All three methods were tested with simulation data and actual in orbit data from the APS star tracker of ZY-3. Using a catalog composed of 1500 stars, the results show that without false stars the efficiency of this new method is 4~5 times that of the pyramid method and 35~37 times that of the geometric method.

  5. Improved autonomous star identification algorithm

    Science.gov (United States)

    Luo, Li-Yan; Xu, Lu-Ping; Zhang, Hua; Sun, Jing-Rong

    2015-06-01

    The log-polar transform (LPT) is introduced into the star identification because of its rotation invariance. An improved autonomous star identification algorithm is proposed in this paper to avoid the circular shift of the feature vector and to reduce the time consumed in the star identification algorithm using LPT. In the proposed algorithm, the star pattern of the same navigation star remains unchanged when the stellar image is rotated, which makes it able to reduce the star identification time. The logarithmic values of the plane distances between the navigation and its neighbor stars are adopted to structure the feature vector of the navigation star, which enhances the robustness of star identification. In addition, some efforts are made to make it able to find the identification result with fewer comparisons, instead of searching the whole feature database. The simulation results demonstrate that the proposed algorithm can effectively accelerate the star identification. Moreover, the recognition rate and robustness by the proposed algorithm are better than those by the LPT algorithm and the modified grid algorithm. Project supported by the National Natural Science Foundation of China (Grant Nos. 61172138 and 61401340), the Open Research Fund of the Academy of Satellite Application, China (Grant No. 2014_CXJJ-DH_12), the Fundamental Research Funds for the Central Universities, China (Grant Nos. JB141303 and 201413B), the Natural Science Basic Research Plan in Shaanxi Province, China (Grant No. 2013JQ8040), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20130203120004), and the Xi’an Science and Technology Plan, China (Grant. No CXY1350(4)).

  6. Star tracker operation in a high density proton field

    Science.gov (United States)

    Miklus, Kenneth J.; Kissh, Frank; Flynn, David J.

    1993-01-01

    Algorithms that reject transient signals due to proton effects on charge coupled device (CCD) sensors have been implemented in the HDOS ASTRA-l Star Trackers to be flown on the TOPEX mission scheduled for launch in July 1992. A unique technique for simulating a proton-rich environment to test trackers is described, as well as the test results obtained. Solar flares or an orbit that passes through the South Atlantic Anomaly can subject the vehicle to very high proton flux levels. There are three ways in which spurious proton generated signals can impact tracker performance: the many false signals can prevent or extend the time to acquire a star; a proton-generated signal can compromise the accuracy of the star's reported magnitude and position; and the tracked star can be lost, requiring reacquisition. Tests simulating a proton-rich environment were performed on two ASTRA-1 Star Trackers utilizing these new algorithms. There were no false acquisitions, no lost stars, and a significant reduction in reported position errors due to these improvements.

  7. Miniature wide field-of-view star trackers for spacecraft attitude sensing and navigation

    Science.gov (United States)

    Mccarty, William; Curtis, Eric; Hull, Anthony; Morgan, William

    1993-01-01

    Introducing a family of miniature, wide field-of-view star trackers for low cost, high performance spacecraft attitude determination and navigation applications. These devices, derivative of the WFOV Star Tracker Camera developed cooperatively by OCA Applied Optics and the Lawrence Livermore National Laboratory for the Brilliant Pebbles program, offer a suite of options addressing a wide range of spacecraft attitude measurement and control requirements. These sensors employ much wider fields than are customary (ranging between 20 and 60 degrees) to assure enough bright stars for quick and accurate attitude determinations without long integration intervals. The key benefit of this approach are light weight, low power, reduced data processing loads and high information carrier rates for wide ACS bandwidths. Devices described range from the proven OCA/LLNL WFOV Star Tracker Camera (a low-cost, space-qualified star-field imager utilizing the spacecraft's own computer and centroiding and position-finding), to a new autonomous subsystem design featuring dual-redundant cameras and completely self-contained star-field data processing with output quaternion solutions accurate to 100 micro-rad, 3 sigma, for stand-alone applications.

  8. Star tracker error analysis: Roll-to-pitch nonorthogonality

    Science.gov (United States)

    Corson, R. W.

    1979-01-01

    An error analysis is described on an anomaly isolated in the star tracker software line of sight (LOS) rate test. The LOS rate cosine was found to be greater than one in certain cases which implied that either one or both of the star tracker measured end point unit vectors used to compute the LOS rate cosine had lengths greater than unity. The roll/pitch nonorthogonality matrix in the TNB CL module of the IMU software is examined as the source of error.

  9. Simulations of silicon vertex tracker for star experiment at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Odyniec, G.; Cebra, D.; Christie, W.; Naudet, C.; Schroeder, L.; Wilson, W. [Lawrence Berkeley Lab., CA (United States); Liko, D. [Institut fur Hochenenergiephysik, Vienna, (Austria); Cramer, J.; Prindle, D.; Trainor, T. [Univ. of Washington, Seattle (United States); Braithwaite, W. [Univ. of Arkansas, Little Rock (United States)

    1991-12-31

    The first computer simulations to optimize the Silicon Vertex Tracker (SVT) designed for the STAR experiment at RHIC are presented. The physics goals and the expected complexity of the events at RHIC dictate the design of a tracking system for the STAR experiment. The proposed tracking system will consist of a silicon vertex tracker (SVT) to locate the primary interaction and secondary decay vertices and to improve the momentum resolution, and a time projection chamber (TPC), positioned inside a solenoidal magnet, for continuous tracking.

  10. Qualification of the next generation of Star Tracker using COTS

    DEFF Research Database (Denmark)

    Guldager, Peter Buch; Aage, Helle Karina

    2005-01-01

    The Star Tracker from ØRSTED•DTU is built by using COTS components (Commercial-Off-The-Shelf) and due to no radiation data exists on COTS components, the EEE components are tested for Radiation effects. The components, which are tested is the one from the same lot, which is going to be used...... for the flight equipment, if they pass the radiation test. The next generation of Star Tracker are using 3-volt technology and this document describes how the COTS components are upscreened for space and how the instrument is qualified for space. The components are TID irradiated and are irradiated until...

  11. ASTROS - A sub-arcsec CCD star tracker

    Science.gov (United States)

    Stanton, R. H.; Alexander, J. W.; Dennison, E. W.; Glavich, T. A.; Salomon, P. M.

    1984-01-01

    The design and application of ASTROS (Advanced Star and Target Reference Optical Sensor) are described, with emphasis on performance test results acquired with a prototype system. The ASTROS tracker provides extremely precise measurements of star image coordinates as inputs to the Image Motion Compensation (IMC) system used to stabilize the science instrument focal planes. Performance levels achieved are dramatic improvements over the levels achieved with image dissector designs with comparable fields of view.

  12. BLAST Autonomous Daytime Star Cameras

    CERN Document Server

    Rex, M; Devlin, M J; Gundersen, J; Klein, J; Pascale, E; Wiebe, D; Rex, Marie; Chapin, Edward; Devlin, Mark J.; Gundersen, Joshua; Klein, Jeff; Pascale, Enzo; Wiebe, Donald

    2006-01-01

    We have developed two redundant daytime star cameras to provide the fine pointing solution for the balloon-borne submillimeter telescope, BLAST. The cameras are capable of providing a reconstructed pointing solution with an absolute accuracy < 5 arcseconds. They are sensitive to stars down to magnitudes ~ 9 in daytime float conditions. Each camera combines a 1 megapixel CCD with a 200 mm f/2 lens to image a 2 degree x 2.5 degree field of the sky. The instruments are autonomous. An internal computer controls the temperature, adjusts the focus, and determines a real-time pointing solution at 1 Hz. The mechanical details and flight performance of these instruments are presented.

  13. Acoustic underwater navigation of the Phoenix Autonomous Underwater Vehicle using the DiveTracker system

    OpenAIRE

    Scrivener, Arthur W.

    1996-01-01

    Autonomous Underwater Vehicles (AUVs) require a navigation system in order to conduct useful functions. This research was an experimental investigation of the commercial DiveTracker underwater acoustic navigation system used onboard the NPS Phoenix AUV. Tests conducted with the DiveTracker system proved that the system could be used successfully in AUV navigation while submerged and revealed that more precise positioning could be obtained through postconditioning of the DiveTracker output ran...

  14. A star pattern recognition algorithm for autonomous attitude determination

    Science.gov (United States)

    Van Bezooijen, R. W. H.

    1990-01-01

    The star-pattern recognition algorithm presented allows the advanced Full-sky Autonomous Star Tracker (FAST) device, such as the projected ASTROS II system of the Mariner Mark II planetary spacecraft, to reliably ascertain attitude about all three axes. An ASTROS II-based FAST, possessing an 11.5 x 11.5 deg field of view and 8-arcsec accuracy, can when integrated with an all-sky data base of 4100 guide stars determine its attitude in about 1 sec, with a success rate close to 100 percent. The present recognition algorithm can also be used for automating the acquisition of celestial targets by astronomy telescopes, autonomously updating the attitude of gyro-based attitude control systems, and automating ground-based attitude reconstruction.

  15. Multi-functional star tracker — future perspectives

    Directory of Open Access Journals (Sweden)

    J. Roháč

    2011-01-01

    Full Text Available This paper focuses on the idea of a multi-functional wide-field star tracker (WFST and provides a description of the current state-of-the-art in this field. The idea comes from a proposal handed in to ESA at the beginning of 2011. Star trackers (STs usually have more than one object-lens with a small Field-of-View. They provide very precise information about the attitude in space according to consecutive evaluation of star positions. Our idea of WFST will combine the functions of several instruments, e.g. ST, a horizon sensor, and an all-sky photometry camera. WFST will use a fish-eye lens. There is no comparable product on the present-day market. Nowadays, spacecraft have to carry several instruments for these applications. This increases the weight of the instrumentation and reduces the weight available for the payload.

  16. Intern Develops Small, Inexpensive Star Tracker

    OpenAIRE

    Stewart, Kenneth A.

    2015-01-01

    Naval Postgraduate School (NPS) student Intern Julian Brown is just 21 years old, but don’t let his young age and boyish charm fool you. He is a serious scientist and is working to build a star tracking system at NPS designed to help very small satellites determine their orientation in space.

  17. A precision star tracker utilizing advanced techniques and materials

    Science.gov (United States)

    Gates, R. F.; Mcaloon, K. J.

    1976-01-01

    An image dissector star tracker has been developed which operates in the photon counting mode making it possible to utilize all digital electronics. A unique pulse processing circuit allows bright stars to be tracked as well as dim stars. Thermal mechanical stability has been greatly enhanced by fabricating a housing with graphite/epoxy composite material with a linear coefficient of thermal expansion near zero. Test results indicate the +10 Mv stars can be acquired and tracked, while position variation with star intensity is less than 2 arc seconds from 2.5 Mv to +10 Mv. The noise equivalent angle for a +8 Mv star is 3 arc seconds. Polynominal correction for remaining cross-coupling and nonlinearity reduced error over total 1 x 1 deg field to 1.5 arc seconds.

  18. Clementine Star Tracker Stellar Compass: Final report part 1

    Energy Technology Data Exchange (ETDEWEB)

    Priest, R.E.; Kordas, J.F.; Lewis, I.T. [and others

    1995-07-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. Two star stracker stellar compasses (star tracker camera + stellar compass software) were included on the spacecraft, serving a primary function of providing angle updates to the guidance and navigation system. These cameras served a secondary function by providing a wide field of view imaging capability for lunar horizon glow and other dark-side imaging data. This 290 g camera using a 576 x 384 focal plane array and a 17 mm entrance pupil, detected and centroided stars as dim and dimmer than 4.5 m{sub v}, providing rms pointing accuracy of better than 100 {mu}rad pitch and yaw and 450 {mu}rad roll. A description of this light-weight, low power star tracker camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission`s primary objective for flight qualifying the sensors for future Department of Defense flights. Documentation generated during the design, analysis, build, test and characterization of the star tracker cameras are presented. Collectively, this documentation represents a small library of information for this camera, and may be used as a framework for producing copy units by commercial enterprises, and therefore satisfies a Department of Defense and Department of Energy goal to transfer technology to industry. However, the considerable knowledge gained from the experience of the individuals involved in the system trades, design, analysis, production, testing and characterization of the star tracker stellar compass is not contained in this documentation.

  19. Star tracker and vision systems performance in a high radiation environment

    DEFF Research Database (Denmark)

    Jørgensen, John Leif; Riis, Troels; Betto, Maurizio

    1999-01-01

    belts twice per orbit. One of the experiments onboard Teamsat was the so-called Autonomous Vision System (AVS). The AVS instrument is a fully autonomous star tracker with several advanced features for non-stellar object detection and tracking, real-time image compression and transmission. The objectives...... for the AVS in Teamsat were to test these functions, to validate their autonomous operation in space, and to assess the operational constraints of a high radiation environment on such processes. This paper describes the AVS experiment, and the radiation flux experienced onboard TEAMSAT. This overview...... is followed by examples of the radiation impact on the AVS instrument flown onboard the TEAMSAT, and finally the operations of the various countermeasures are discussed....

  20. Star tracker stellar compass for the Clementine mission

    Science.gov (United States)

    Kordas, Joseph F.; Lewis, Isabella T.; Wilson, Bruce A.; Nielsen, Darron P.; Park, Hye-Sook; Priest, Robert E.; Hills, Robert F.; Shannon, Michael J.; Ledebuhr, Arno G.; Pleasance, Lyn D.

    1995-06-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared region. More than 1.7 million images of the moon, earth and space were returned from this mission. Two star tracker stellar compasses (star tracker camera + stellar compass software) were included on the spacecraft, serving a primary function of providing angle updates to the guidance and navigation system. These cameras served as a secondary function by providing a wide field of view imaging capability for lunar horizon glow and other dark-side imaging data. This 290 g camera using a 576 X 384 FPA and a 17 mm entrance pupil, detected and centroided stars as dim and dimmer than 4.5 mv, providing rms pointing accuracy of better than 100 (mu) rad pitch and yaw and 450 (mu) rad roll. A description of this light-weight, low power star tracker camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission's primary objective for flight qualifying the sensors for future Department of Defense flights.

  1. Star tracker stellar compass for the Clementine mission

    Energy Technology Data Exchange (ETDEWEB)

    Kordas, J.F.; Lewis, I.T.; Wilson, B.A. [and others

    1995-04-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. Two star tracker stellar compasses (star tracker camera + stellar compass software) were included on the spacecraft, serving a primary function of providing angle updates to the guidance and navigation system. These cameras served a secondary function by providing a wide field of view imaging capability for lunar horizon glow and other dark-side imaging data. This 290 g camera using a 576 x 384 FPA and a 17 mm entrance pupil, detected and centroided stars as dim and dimmer than 4.5 m{sub v}, providing rms pointing accuracy of better than 100 {micro}rad pitch and yaw and 450 {micro}rad roll. A description of this light-weight, low power star tracker camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission`s primary objective for flight qualifying the sensors for future Department of Defense flights.

  2. Spacecraft Attitude Determination Simulation and Experiment to Improve the Efficiency of a Star Tracker

    OpenAIRE

    Houtz, Nathan; Frueh, Carolin, Dr.

    2015-01-01

    Knowing a spacecraft’s orientation is crucial for many vital functions. Attitude is often determined using a star tracker. Star tracker attitude determination must be fast and efficient given the limited on board computing resources. To determine its attitude, a star tracker must take an image of its environment, locate the stars in that image, recognize a pattern among those stars, match it with patterns in a catalog, and determine the rotation matrix that relates the spacecraft to the inert...

  3. COTS Detectors for Nanosatellite Star Trackers: A Case Study

    OpenAIRE

    Enright, John; Sinclair, Doug; Fernando, Christy

    2011-01-01

    In recent years, many imaging sensors for small satellites have adopted CMOS active pixel sensors. The Aptina MT9P031 in particular, has seen many adopters. This paper presents lessons learned from our experience integrating this detector with the Sinclair Interplanetary S3S Star Tracker. We present practical advice for handling and assembly and discuss strategies for maximizing image quality over the sensor lifetime. In particular, we characterize the noise characteristics from several units...

  4. Acquisition and track algorithms for the Astros star tracker

    Science.gov (United States)

    Shalom, E.; Alexander, J. W.; Stanton, R. H.

    1985-01-01

    The Astros star tracker has been designed for an employment with the Space Shuttle. An achievement of the performance levels needed has required critical trade-offs between the hardware design and the control algorithms. This paper provides a description of the development of the acquisition and track algorithms. Attention is given to an Astros system overview, a system firmware description, cluster evaluation, guide star selection, exposure time determination, video data input, update interval timing, exposure time sequencing full frame video A/D conversion, analog threshold for acquisition, minimum threshold determination, and the theoretical basis for the track algorithm.

  5. Ground Testing Strategies for Verifying the Slew Rate Tolerance of Star Trackers

    OpenAIRE

    Tom Dzamba; John Enright

    2014-01-01

    The performance of a star tracker is largely based on the availability of its attitude solution. Several methods exist to assess star tracker availability under both static and dynamic imaging conditions. However, these methods typically make various idealizations that can limit the accuracy of these results. This study aims to increase the fidelity of star tracker availability modeling by accounting for the effects of detection logic and pixel saturation on star detection. We achieve this by...

  6. Motion-blurred star acquisition method of the star tracker under high dynamic conditions.

    Science.gov (United States)

    Sun, Ting; Xing, Fei; You, Zheng; Wei, Minsong

    2013-08-26

    The star tracker is one of the most promising attitude measurement devices used in spacecraft due to its extremely high accuracy. However, high dynamic performance is still one of its constraints. Smearing appears, making it more difficult to distinguish the energy dispersive star point from the noise. An effective star acquisition approach for motion-blurred star image is proposed in this work. The correlation filter and mathematical morphology algorithm is combined to enhance the signal energy and evaluate slowly varying background noise. The star point can be separated from most types of noise in this manner, making extraction and recognition easier. Partial image differentiation is then utilized to obtain the motion parameters from only one image of the star tracker based on the above process. Considering the motion model, the reference window is adopted to perform centroid determination. Star acquisition results of real on-orbit star images and laboratory validation experiments demonstrate that the method described in this work is effective and the dynamic performance of the star tracker could be improved along with more identified stars and guaranteed position accuracy of the star point. PMID:24105556

  7. Thermal/Optical analysis of optical system of star tracker

    Science.gov (United States)

    Lu, Si-yu; Huang, Yi-fan

    2011-08-01

    Spacecraft would be expected to encounter diverse extreme environmental (EE) conditions throughout their mission phases. These EE conditions are often coupled. Star tracker is a high accurate 3-axis attitude measuring instrument used in various spacecrafts. In this paper, an effective scheme to the thermal/optical analysis in optical system of star sensor was described and the concept of thermal optical analysis of star tracker optical system was introduced in detail. Using finite element analysis (FEA) and ray tracing, we can study the relationship of optical properties of optical systems and optical system's temperature distribution . A lens system configuration having six uncemented elements was discussed. The lens system was a 56mm EFL, which was different from common lens used in imaging system that this lens system was required to have a high resolving power in design thoughts. It was designed to determine the attitude of space platform by detecting and mapping the geometric pattern of stars. Based on this system, the FEA models of the optical system were established for temperature distribution calculation and for thermal-elastic structural deformation analysis respectively. Using the models, the steady-state temperature distributions of the tracker were simulated. The rigid body displacements of the optical components under homogeneous temperature changes and certain temperature distributions were derived out. It is convenient to use Zernike polynomials as the data transmission between optical and structural analysis programs. Here, Zernike polynomials and their fitting method are used as an example to determine the thermal induced optical degradations of the optical system.

  8. Precision Attitude Determination System (PADS) system design and analysis: Single-axis gimbal star tracker

    Science.gov (United States)

    1974-01-01

    The feasibility is evaluated of an evolutionary development for use of a single-axis gimbal star tracker from prior two-axis gimbal star tracker based system applications. Detailed evaluation of the star tracker gimbal encoder is considered. A brief system description is given including the aspects of tracker evolution and encoder evaluation. System analysis includes evaluation of star availability and mounting constraints for the geosynchronous orbit application, and a covariance simulation analysis to evaluate performance potential. Star availability and covariance analysis digital computer programs are included.

  9. A star identification algorithm based on a voting scheme for star trackers

    Directory of Open Access Journals (Sweden)

    M. Hamidi

    2014-04-01

    Full Text Available Star identification is one of the most important stages in attitude determination with star trackers. This can be performed using matching algorithms between observed stars and a master star catalogue. The main challenge in this approach is to provide a fast and reliable identification algorithm that is sufficiently robust in different pointing views of the star tracker optical system in the space. In this article, an identification algorithm based on a geometric voting scheme is presented. In this algorithm a pair of stars in the catalogue votes for a pair of stars in the image if angular distance between the stars of both pairs is similar. As angular distance is a symmetric relationship, each of the two catalogue stars votes for each of the image stars. The identity of each star in the image is set to the identity of the catalogue star which cast the most votes. Applying the algorithm in different attitudes and with different optical system parameters shows its high performance in star identification in our simulations.

  10. The STAR Heavy Flavor Tracker PXL detector readout electronics

    Science.gov (United States)

    Schambach, J.; Contin, G.; Greiner, L.; Stezelberger, T.; Sun, X.; Szelezniak, M.; Vu, C.

    2016-01-01

    The Heavy Flavor Tracker (HFT) is a recently installed micro-vertex detector upgrade to the STAR experiment at RHIC, consisting of three subsystems with various technologies of silicon sensors arranged in 4 concentric cylinders. The two innermost layers of the HFT close to the beam pipe, the Pixel ("PXL") subsystem, employ CMOS Monolithic Active Pixel Sensor (MAPS) technology that integrate the sensor, front-end electronics, and zero-suppression circuitry in one silicon die. This paper presents selected characteristics of the PXL detector part of the HFT and the hardware, firmware and software associated with the readout system for this detector.

  11. Adaptive Neural Star Tracker Calibration for Precision Spacecraft Pointing and Tracking

    Science.gov (United States)

    Bayard, David S.

    1996-01-01

    The Star Tracker is an essential sensor for precision pointing and tracking in most 3-axis stabilized spacecraft. In the interest (of) improving pointing performance by taking advantage of dramatic increases in flight computer power and memory anticipated over the next decade, this paper investigates the use of a neural net for adaptive in-flight calibration of the Star Tracker.

  12. Angular velocity estimation from measurement vectors of star tracker.

    Science.gov (United States)

    Liu, Hai-bo; Yang, Jun-cai; Yi, Wen-jun; Wang, Jiong-qi; Yang, Jian-kun; Li, Xiu-jian; Tan, Ji-chun

    2012-06-01

    In most spacecraft, there is a need to know the craft's angular rate. Approaches with least squares and an adaptive Kalman filter are proposed for estimating the angular rate directly from the star tracker measurements. In these approaches, only knowledge of the vector measurements and sampling interval is required. The designed adaptive Kalman filter can filter out noise without information of the dynamic model and inertia dyadic. To verify the proposed estimation approaches, simulations based on the orbit data of the challenging minisatellite payload (CHAMP) satellite and experimental tests with night-sky observation are performed. Both the simulations and experimental testing results have demonstrated that the proposed approach performs well in terms of accuracy, robustness, and performance. PMID:22695598

  13. Optimal estimation for the satellite attitude using star tracker measurements

    Science.gov (United States)

    Lo, J. T.-H.

    1986-01-01

    An optimal estimation scheme is presented, which determines the satellite attitude using the gyro readings and the star tracker measurements of a commonly used satellite attitude measuring unit. The scheme is mainly based on the exponential Fourier densities that have the desirable closure property under conditioning. By updating a finite and fixed number of parameters, the conditional probability density, which is an exponential Fourier density, is recursively determined. Simulation results indicate that the scheme is more accurate and robust than extended Kalman filtering. It is believed that this approach is applicable to many other attitude measuring units. As no linearization and approximation are necessary in the approach, it is ideal for systems involving high levels of randomness and/or low levels of observability and systems for which accuracy is of overriding importance.

  14. TRACKER

    CERN Multimedia

    C. Barth

    2012-01-01

      Strip Tracker In the end of 2011, the Silicon Strip Tracker participated in the very successful heavy-ion collision data-taking. With zero downtime attributed to the Strip Tracker, CMS could achieve the excellent efficiency of 96%. Thus we were able to improve on the already good uptime during pp collisions, and completed an excellent year for the Strip Tracker. The shift of responsibility to raise the high voltages at the declaration of Stable Beams from the Tracker DOC to the central crew went smoothly. The new scheme is working reliably and we improved our automatic DQM and DCS SMS services. With this further improvement we plan to discontinue calling the TK DOC at each Stable Beam; so far the TK DOC personally checked all systems. The biggest effort of this Year-End Technical Stop was a comprehensive evaluation of the C6F14 cooling system performance with respect to future cold operation. The analysis allows a dedicated planning of system refurbishments to be executed during 2012 and LS1....

  15. Star trackers, star catalogs, and attitude determination - Probabilistic aspects of system design

    Science.gov (United States)

    Vedder, John D.

    1992-01-01

    Optimizing spacecraft attitude determination systems that use onboard star trackers requires analysis and evaluation of some probabilistic aspects of system design. This paper discusses methods of constructing or compiling optimum star catalogs, which are defined as uniform distributions on a sphere. Both local and global measures of uniformity on a sphere are defined. Application of these methods and measures to a specific problem is also discussed. In addition, Poisson models of star tracker acquisition probabilities are formulated to provide a useful analytical basis for designing and optimizing attitude determination systems. These analytical models and methods lead to rapid and realistic quantitative results, and should therefore facilitate making system performance trades. Use of such methods should also reduce the need for performing tedious computer simulations to obtain analogous results.

  16. Fast and Robust pointing and tracking using a second-generation star tracker

    DEFF Research Database (Denmark)

    Jørgensen, John Leif; Pickles, Andrew

    1998-01-01

    Second generation star trackers work by taking wide-angle optical pictures of star fields, correlating the image against a star catalogue in ROM, centroiding many stars to derive an accurate position and orientation. This paper describes a miniature instrument(10cm cube), fast and lightweight (85...

  17. The Forward GEM Tracker of STAR at RHIC

    CERN Document Server

    Simon, F; Fatemi, R; Hasell, D; Kelsey, J; Majka, R; Page, B; Plesko, M; Underwood, D; Smirnov, N; Sowinski, J; Spinka, H; Surrow, B; Visser, G

    2008-01-01

    The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is in the process of designing and constructing a forward tracking system based on triple GEM technology. This upgrade is necessary to give STAR the capability to reconstruct and identify the charge sign of W bosons over an extended rapidity range through their leptonic decay mode into an electron (positron) and a neutrino. This will allow a detailed study of the flavor-separated spin structure of the proton in polarized p + p collisions uniquely available at RHIC. The Forward GEM Tracker FGT will consist of six triple GEM disks with an outer radius of ~39 cm and an inner radius of ~10.5 cm, arranged along the beam pipe, covering the pseudo-rapidity range from 1.0 to 2.0 over a wide range of collision vertices. The GEM foils will be produced by Tech-Etch, Inc. Beam tests with test detectors using 10 cm x 10 cm Tech-Etch GEM foils and a two dimensional orthogonal strip readout have demonstrated a spatial r...

  18. Optical System Error Analysis and Calibration Method of High-Accuracy Star Trackers

    OpenAIRE

    Zheng You; Fei Xing; Ting Sun

    2013-01-01

    The star tracker is a high-accuracy attitude measurement device widely used in spacecraft. Its performance depends largely on the precision of the optical system parameters. Therefore, the analysis of the optical system parameter errors and a precise calibration model are crucial to the accuracy of the star tracker. Research in this field is relatively lacking a systematic and universal analysis up to now. This paper proposes in detail an approach for the synthetic error analysis of the star ...

  19. Systematic error analysis and compensation for high accuracy star centroid estimation of star tracker

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Subpixel centroid estimation is the most important star image location method of star tracker. This paper presents a theoretical analysis of the systematic error of subpixel centroid estimation algorithm utilizing frequency domain analysis under the con-sideration of sampling frequency limitation and sampling window limitation. Explicit expression of systematic error of cen-troid estimation is obtained, and the dependence of systematic error on Gaussian width of star image, actual star centroid loca-tion and the number of sampling pixels is derived. A systematic error compensation algorithm for star centroid estimation is proposed based on the result of theoretical analysis. Simulation results show that after compensation, the residual systematic errors of 3-pixel-and 5-pixel-windows’ centroid estimation are less than 2×10-3 pixels and 2×10-4 pixels respectively.

  20. TRACKER

    CERN Document Server

    L. Demaria

    2011-01-01

    Strip Tracker The Silicon Strip Tracker has maintained excellent operational performance during the 2011 data-taking period. The increase of instantaneous luminosity up to 1033 cm-2s-1 did not introduce any new issues in the detector. The detector has collected high-quality physics data with an uptime greater than 98%. Sources of downtime have been identified and problems were properly addressed. Improved firmware in the Front-End Driver (FED) firmware was deployed to increase the robustness of the readout against spurious extra frames coming from the detector. When a FED detects bad data, it goes into Out-Of-Sync (OOS) status, waits for a L1 resynchronisation command (resync) to clean up the culprit data and restarts. Resync commands are now sent automatically to the Strip Tracker when it signals OOS and, as a result, this source of downtime has been reduced significantly. The dead-time, caused by recoveries from OOS, accounts for less than 0.1%. Downtime was also found to be caused by a FED occasionally ge...

  1. TRACKER

    CERN Multimedia

    D. Strom

    2011-01-01

    Strip Tracker Since the June CMS Week, the Silicon Strip Tracker has had another period of excellent detector operation with more than 97% system uptime. The focus on stable proton physics collection was fruitful, as CMS recorded greater than 5 fb–1 by the completion of the 2011 pp run. Following the November machine development and technical stop, the Strip Tracker now aims to provide the highest quality data during the heavy-ion run. The detector health, measured by the fraction of alive channels, is largely stable at around 97.8%. Recent failures include a TOB control ring, which now requires redundancy, and a TEC control ring with intermittent failures. These will be investigated during the Year-End Technical Stop. Critical services are very stable. The cooling system has a low total leak rate of less than 1 kg per day, and the power supply exchange rate is less than 1 unit per month. Two operational changes recently went into effect to optimise data-taking efficiency: (1) a tripped power su...

  2. TRACKER

    CERN Multimedia

    Frank Hartmann

    2012-01-01

      Strip Tracker In general, the Strip Tracker is operating smoothly with the current peak instantaneous luminosity beyond 6.5E33, high L1 rate and large pile-up. With several improvements in automatic DQM checks and an enhanced SMS and e-mail service system plus additional audio alarms, we have reduced the work-load of our TK DOC and stopped the calls made at the beginning of each fill. We successfully collected more than two million cosmic tracks in peak mode during inter-fill periods before June, fulfilling the request from the Tracker alignment group. Around 500k cosmic tracks were also collected at zero Tesla. All planned special measurements, namely DCU calibration and I-V scans, have been taken during the YETS and other technical stops. A peak-mode run, a delay run and two HV scans have also been taken during early collisions at the initial low-lumi runs as well as during the fill where CMS had a problem with the magnet. The largest source of downtime comes from TIB-2.8.1 a.k.a. FED 101, ...

  3. TRACKER

    CERN Multimedia

    G. Dirkes

    2010-01-01

    The strip system has generally exhibited stable and high performance operation during the last six months of pp and heavy ion collisions. The up-time during pp collision from June onwards was 99.0% and during the first weeks of heavy-ion running we reached 99.7%. Most of the down-time during the proton runs came from Tracker DAQ problems. Spurious extra events from individual front-end channels caused ‘sync loss draining’ errors at the central DAQ system downstream of the Tracker FEDs. Once the problem was understood, new firmware that detects this error condition was installed on the FEDs. This has reduced the recovery procedure from this particular condition from a full reconfiguration requiring 170 s, to a simple re-synchronisation taking only ~1 s. We have also streamlined the instructions for the central DAQ shifters in order to minimise the time needed to decide the proper reaction to a given problem. The average down-time for problems triggered by the strip tracker DAQ is 395 s. Th...

  4. Compensation for Time-Dependent Star Tracker Thermal Deformation on the Aqua Spacecraft

    Science.gov (United States)

    Hashmall, Joseph A.; Natanson, Gregory; Glickman, Jonathan; Sedlak, Joseph

    2004-01-01

    Analysis of attitude sensor data from the Aqua mission showed small but systematic differences between batch least-squares and extended Kalman filter attitudes. These differences were also found to be correlated with star tracker residuals, gyro bias estimates, and star tracker baseplate temperatures. This paper describes the analysis that shows that these correlations are all consistent with a single cause: time-dependent thermal deformation of star tracker alignments. These varying alignments can be separated into relative and common components. The relative misalignments can be determined and compensated for. The common misalignments can only be determined in special cases.

  5. Post flight analysis of NASA standard star trackers recovered from the solar maximum mission

    Science.gov (United States)

    Newman, P.

    1985-01-01

    The flight hardware returned after the Solar Maximum Mission Repair Mission was analyzed to determine the effects of 4 years in space. The NASA Standard Star Tracker would be a good candidate for such analysis because it is moderately complex and had a very elaborate calibration during the acceptance procedure. However, the recovery process extensively damaged the cathode of the image dissector detector making proper operation of the tracker and a comparison with preflight characteristics impossible. Otherwise, the tracker functioned nominally during testing.

  6. A Method for Detecting Resident Space Objects and Orbit Determination Based on Star Trackers and Image Analysis

    OpenAIRE

    Bengtsson Bernander, Karl

    2014-01-01

    Satellites commonly use onboard digital cameras, called star trackers. A star tracker determines the satellite's attitude, i.e. its orientation in space, by comparing star positions with databases of star patterns. In this thesis, I investigate the possibility of extending the functionality of star trackers to also detect the presence of resident space objects (RSO) orbiting the earth. RSO consist of both active satellites and orbital debris, such as inactive satellites, spent rocket stages a...

  7. TAB Bonded SSD Module for the STAR and ALICE Trackers

    CERN Document Server

    Lutz, Jean Robert; Baudot, J; Bonnet, D; Coffin, J P; Germain, M; Gojak, C; Jundt, F; Kühn, C E; Suire, C; Tarchini, A; Berst, D; Clauss, G; Colledani, C; Dulinski, W; Boucham, A; Bouvier, S; Castillo, J; Drancourt, C; Erazmus, B; Guilloux, G; Martin, L; Roy, C

    1999-01-01

    Presentation made at LEB99, 20-24 September 1999A novel compact detector module has been produced by the "IReS"-"Subatech"-"Thomson-CSF-Detexis" collaboration. It includes a Double-Sided (DS) Silicon Strip Detector (SSD) and the related Front End Electronics (FEE) located on two hybrids, one for the N side and one for the P side. Bumpless Tape Automated Bonding (TAB) is used to connect the detector to the hybrids by means of microcables with neither wirebonding nor pitch adapter. Each of the six dedicated ALICE128C FE chip [1], located on the hybrid, is TABed on identical single layer microcables, which connect its inputs to the DS SSD and its outputs to the hybrid [2]. These microcables are bent in order to fold over the two hybrids on the DS SSD. This module meets the specifications of two experiments, ALICE (A Large Ion Collider Experiment) on the LHC accelerator at CERN [3] and STAR (Solenoid Tracker At Rhic) on the RHIC accelerator at BNL (Brookhaven National Laboratory)[4]. It can be used with air cooli...

  8. TRACKER

    CERN Document Server

    K. Gill and G. Bolla

    2010-01-01

    Silicon strips During the first collisions the strip-Tracker operated with excellent performance and stability. The results obtained were very impressive and this exciting experience marked a fine end to another intense year. Several issues were identified during 2009 operations that could benefit from improvement: to suppress the increased output data volume when in STANDBY state (LV ON, HV OFF), which is due to the larger noise amplitudes when the sensors are unbiased; to reduce the strips configuration time; to increase the stability of the power system, particularly during state transitions, and to decrease the powering up time. The strip-Tracker FEDs now react to changes in the HV conditions of the strips. Upon a transition to STAND-BY, central DAQ starts a PAUSE-RESUME cycle and a flag is issued to the FEDSupervisor. This results in forcing the common mode noise artificially to the maximum value, which effectively suppresses the analogue data output. This forced offset is removed as soon as the strips ...

  9. TRACKER

    CERN Multimedia

    K. Gill

    2010-01-01

    The Tracker has continued to operate with excellent performance during this first period with 7 TeV collisions. Strips operations have been very smooth. The up-time during collisions was 98.5%, up to end of May, with a large fraction of the down-time coming during the planned fine-timing scan with early 7 TeV collisions. Pixels operations are also going very well, besides problems related to background beam-gas collisions where the particles produced generate very large clusters in the barrel modules. When CMS triggers on these events, the FEDs affected overflow and then timeout. Effort was mobilised very quickly to understand and mitigate this problem, with modifications made to the pixel FED firmware in order to provide automatic recovery. With operations becoming more and more routine at P5, Pixels have begun the transition to centrally attended operation, which means that the P5 shifters will no longer be required to be on duty. The strip-Tracker is also planning to make this transition at the end of Ju...

  10. TRACKER

    CERN Multimedia

    Bora Akgun

    2013-01-01

    Pixel Tracker Maintenance of the Pixel Tracker has been ongoing since it was extracted from inside CMS and safely stored at low temperatures in Pixel laboratory at Point 5 (see previous Bulletin).    All four half cylinders of the forward Pixel detector (FPIX) have been repaired and the failures have been understood. In October, a team of technicians from Fermilab replaced a total of three panels that were not repairable in place. The replacement of panels is a delicate operation that involves removing the half disks that hold the panels from the half cylinders, removing the damaged panels from the half disks, installing the new panels on the half disks, and finally putting the half disks back into the half cylinders and hooking up the cooling connections. The work was completed successfully. The same team also prepared the installation of the Phase 1 Pixel pilot blade system, installing a third half disk mechanics in the half cylinders; these half disks will host new Phase 1 P...

  11. Spacecraft attitude control systems with dynamic methods and structures for processing star tracker signals

    Science.gov (United States)

    Liu, Yong (Inventor); Wu, Yeong-Wei Andy (Inventor); Li, Rongsheng (Inventor)

    2001-01-01

    Methods are provided for dynamically processing successively-generated star tracker data frames and associated valid flags to generate processed star tracker signals that have reduced noise and a probability greater than a selected probability P.sub.slctd of being valid. These methods maintain accurate spacecraft attitude control in the presence of spurious inputs (e.g., impinging protons) that corrupt collected charges in spacecraft star trackers. The methods of the invention enhance the probability of generating valid star tracker signals because they respond to a current frame probability P.sub.frm by dynamically selecting the largest valid frame combination whose combination probability P.sub.cmb satisfies a selected probability P.sub.slctd. Noise is thus reduced while the probability of finding a valid frame combination is enhanced. Spacecraft structures are also provided for practicing the methods of the invention.

  12. Integrated CubeSat ADACS with Reaction Wheels and Star Tracker Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A high performance ADACS (Attitude Determination and Control System) for CubeSats incorporating Miniature Star Trackers is proposed. The proposed program will focus...

  13. Ultra-Miniaturized Star Tracker for Small Satellite Attitude Control Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Creare and Virginia Polytechnic Institute and State University propose to design, develop, test, and deliver an ultra compact star tracker specifically intended for...

  14. Ultra-Miniaturized Star Tracker for Small Satellite Attitude Control Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Creare and Embry-Riddle Aeronautical University (ERAU) propose to complete the design, development, and testing of an ultra compact star tracker specifically...

  15. The Things You Can’t Ignore: Evolving a Sub-Arcsecond Star Tracker

    OpenAIRE

    Enright, John; Sinclair, Doug; Dzamba, Tom

    2012-01-01

    The feasibility of a star tracker with 1 arc-second accuracy and 1 deg/sec slew capability is explored, using the ST-16 design as a starting point. Whole-sky simulation is used to determine the impact of optical design on the star tracker availability. The current optical calibration process is examined, and shown to be inadequate for the desired performance. Additional factors that become important at high accuracy are examined. These are detector calibration, temperature variation, chromati...

  16. Development of a low cost star tracker for the SHEFEX mission

    OpenAIRE

    Samaan, Malak; Theil, Stephan

    2011-01-01

    German Aerospace Center (DLR) is designing and developing a novel star tracker to be used as the primary attitude sensor for the SHEFEX mission. The developed star tracker is considered to be a low cost and low accuracy sensor that is suitable for the proposed mission and the attitude accuracy requirements. This sensor is based on an off-the-shelf camera and a PC/104 computer communicating with the navigation computer. The attitude determination software consists of a processing chain incl...

  17. Optical system error analysis and calibration method of high-accuracy star trackers.

    Science.gov (United States)

    Sun, Ting; Xing, Fei; You, Zheng

    2013-01-01

    The star tracker is a high-accuracy attitude measurement device widely used in spacecraft. Its performance depends largely on the precision of the optical system parameters. Therefore, the analysis of the optical system parameter errors and a precise calibration model are crucial to the accuracy of the star tracker. Research in this field is relatively lacking a systematic and universal analysis up to now. This paper proposes in detail an approach for the synthetic error analysis of the star tracker, without the complicated theoretical derivation. This approach can determine the error propagation relationship of the star tracker, and can build intuitively and systematically an error model. The analysis results can be used as a foundation and a guide for the optical design, calibration, and compensation of the star tracker. A calibration experiment is designed and conducted. Excellent calibration results are achieved based on the calibration model. To summarize, the error analysis approach and the calibration method are proved to be adequate and precise, and could provide an important guarantee for the design, manufacture, and measurement of high-accuracy star trackers. PMID:23567527

  18. Optical System Error Analysis and Calibration Method of High-Accuracy Star Trackers

    Directory of Open Access Journals (Sweden)

    Zheng You

    2013-04-01

    Full Text Available The star tracker is a high-accuracy attitude measurement device widely used in spacecraft. Its performance depends largely on the precision of the optical system parameters. Therefore, the analysis of the optical system parameter errors and a precise calibration model are crucial to the accuracy of the star tracker. Research in this field is relatively lacking a systematic and universal analysis up to now. This paper proposes in detail an approach for the synthetic error analysis of the star tracker, without the complicated theoretical derivation. This approach can determine the error propagation relationship of the star tracker, and can build intuitively and systematically an error model. The analysis results can be used as a foundation and a guide for the optical design, calibration, and compensation of the star tracker. A calibration experiment is designed and conducted. Excellent calibration results are achieved based on the calibration model. To summarize, the error analysis approach and the calibration method are proved to be adequate and precise, and could provide an important guarantee for the design, manufacture, and measurement of high-accuracy star trackers.

  19. TRACKER

    CERN Multimedia

    R. Yohay and E. Butz

    2013-01-01

      Pixel Tracker Preparation of the newly built Pixel clean room in the radioprotection (RP) zone of SX5 has been proceeding at a steady clip since the beginning of 2013. The clean room is designed to provide a cold, dry, dust-free laboratory environment for storage and repairs of the CMS Pixel detector during LS1 and future LHC shutdown periods. To that end, it is required to have robust temperature and humidity control, standalone DAQ and DCS systems, and space for specialised silicon testing and repair equipment. Good progress has been made in delivering each of these items. The ongoing project of commissioning the clean room HVAC system has been a success so far. The clean room will be kept at 10–20 Pa above atmospheric pressure to ensure that contaminants flow out of the room. There are two operating temperatures for the room: 21°C will be used when the Pixel detector components are under cold storage at subzero temperatures in well-sealed “cold boxes,” ...

  20. TRACKER

    CERN Multimedia

    D. Duggan and L. Demaria

    2012-01-01

    Pixels Tracker With the 2012 proton-proton run almost complete, the pixel detector continues to operate well in an environment with large pile-up and high L1 rate. During this period, the pixel detector has shown excellent stability, with the number of current active channels from each the BPIX and FPIX the same as from the first month of 2012 running, resulting in 96.3% of the detector active. This total includes the recovery of six FPIX channels, temporarily disabled due to an unexpected dependence on the magnetic field. From a dedicated study that identified a small crack in an optical cable connector, a repair was made which restored 120 ROCs in the FPIX. During 2012 there has been a close collaboration of the online operations with the offline studies, resulting in the first dedicated HV bias scans used for the pixel Lorentz Angle measurement. These scans help to better understand this important parameter that changes with temperature, irradiation, and bias voltage. This is in addition to all other s...

  1. TRACKER

    CERN Multimedia

    M. Dinardo and G. Benelli

    2013-01-01

    Pixel Tracker At the beginning of May, the Pixel detector was successfully extracted from inside CMS. The operation lasted one and a half days each for the forward and barrel Pixel detectors. Everything went smoothly: new people were trained during the exercise and care was taken to minimise radiation exposure – see Image 3.  Lessons learned were noted in an updated written extraction procedure.  Care was also taken to prepare for reinsertion around the new beam pipe next year, with new alignment targets placed on the barrel Pixel detector. All pieces were lifted to the surface and are now safely stored at low temperatures in the dedicated Pixel laboratory at Point 5 (see Image 4 and previous Bulletin). Image 3 (a) and (b): Extracted FPIX and BPIX detector The subsequent maintenance of the forward Pixel detector started on 27 May.  Since then one of four half cylinders has been repaired and, even more importantly, most of the failures have been fully understood. ...

  2. TRACKER

    CERN Multimedia

    E. Butz

    2011-01-01

    The strip tracker took data very efficiently during 2010 with system availabilities of above 97% in the pp running and close to 100% during the heavy-ion running. The number of active channels in the readout is largely stable around 98%. The maintenance and development during the extended technical stop have been focussed on improving the operating conditions of the main silicon strip cooling plants SS1 and SS2, which have been items of concern (see last Bulletin). In order to stabilise and smooth the operation of SS1 and SS2, larger bypass valves and variable frequency drivers (VFDs) have been introduced. Possible noise induced by operation of the VFDs on other parts of CMS has been evaluated and no increased noise has been reported so far. The leak rate of every single line on SS2 was measured with the precise test-rig. Besides the known leaky lines, ten other SS2 lines were measured to leak between 120 g/day and 1200 g/day under the given test conditions, establishin...

  3. An accuracy measurement method for star trackers based on direct astronomic observation

    Science.gov (United States)

    Sun, Ting; Xing, Fei; Wang, Xiaochu; You, Zheng; Chu, Daping

    2016-03-01

    Star tracker is one of the most promising optical attitude measurement devices and it is widely used in spacecraft for its high accuracy. However, how to realize and verify such an accuracy remains a crucial but unsolved issue until now. The authenticity of the accuracy measurement method of a star tracker will eventually determine the satellite performance. A new and robust accuracy measurement method for a star tracker based on the direct astronomical observation is proposed here. In comparison with the conventional method with simulated stars, this method utilizes real navigation stars as observation targets which makes the measurement results more authoritative and authentic. Transformations between different coordinate systems are conducted on the account of the precision movements of the Earth, and the error curves of directional vectors are obtained along the three axes. Based on error analysis and accuracy definitions, a three-axis accuracy evaluation criterion has been proposed in this paper, which could determine pointing and rolling accuracy of a star tracker directly. Experimental measurements confirm that this method is effective and convenient to implement. Such a measurement environment is close to the in-orbit conditions and it can satisfy the stringent requirement for high-accuracy star trackers.

  4. An accuracy measurement method for star trackers based on direct astronomic observation.

    Science.gov (United States)

    Sun, Ting; Xing, Fei; Wang, Xiaochu; You, Zheng; Chu, Daping

    2016-01-01

    Star tracker is one of the most promising optical attitude measurement devices and it is widely used in spacecraft for its high accuracy. However, how to realize and verify such an accuracy remains a crucial but unsolved issue until now. The authenticity of the accuracy measurement method of a star tracker will eventually determine the satellite performance. A new and robust accuracy measurement method for a star tracker based on the direct astronomical observation is proposed here. In comparison with the conventional method with simulated stars, this method utilizes real navigation stars as observation targets which makes the measurement results more authoritative and authentic. Transformations between different coordinate systems are conducted on the account of the precision movements of the Earth, and the error curves of directional vectors are obtained along the three axes. Based on error analysis and accuracy definitions, a three-axis accuracy evaluation criterion has been proposed in this paper, which could determine pointing and rolling accuracy of a star tracker directly. Experimental measurements confirm that this method is effective and convenient to implement. Such a measurement environment is close to the in-orbit conditions and it can satisfy the stringent requirement for high-accuracy star trackers. PMID:26948412

  5. An accuracy measurement method for star trackers based on direct astronomic observation

    Science.gov (United States)

    Sun, Ting; Xing, Fei; Wang, Xiaochu; You, Zheng; Chu, Daping

    2016-01-01

    Star tracker is one of the most promising optical attitude measurement devices and it is widely used in spacecraft for its high accuracy. However, how to realize and verify such an accuracy remains a crucial but unsolved issue until now. The authenticity of the accuracy measurement method of a star tracker will eventually determine the satellite performance. A new and robust accuracy measurement method for a star tracker based on the direct astronomical observation is proposed here. In comparison with the conventional method with simulated stars, this method utilizes real navigation stars as observation targets which makes the measurement results more authoritative and authentic. Transformations between different coordinate systems are conducted on the account of the precision movements of the Earth, and the error curves of directional vectors are obtained along the three axes. Based on error analysis and accuracy definitions, a three-axis accuracy evaluation criterion has been proposed in this paper, which could determine pointing and rolling accuracy of a star tracker directly. Experimental measurements confirm that this method is effective and convenient to implement. Such a measurement environment is close to the in-orbit conditions and it can satisfy the stringent requirement for high-accuracy star trackers. PMID:26948412

  6. Precision Attitude Determination System (PADS) design and analysis. Two-axis gimbal star tracker

    Science.gov (United States)

    1973-01-01

    Development of the Precision Attitude Determination System (PADS) focused chiefly on the two-axis gimballed star tracker and electronics design improved from that of Precision Pointing Control System (PPCS), and application of the improved tracker for PADS at geosynchronous altitude. System design, system analysis, software design, and hardware design activities are reported. The system design encompasses the PADS configuration, system performance characteristics, component design summaries, and interface considerations. The PADS design and performance analysis includes error analysis, performance analysis via attitude determination simulation, and star tracker servo design analysis. The design of the star tracker and electronics are discussed. Sensor electronics schematics are included. A detailed characterization of the application software algorithms and computer requirements is provided.

  7. Ground testing strategies for verifying the slew rate tolerance of star trackers.

    Science.gov (United States)

    Dzamba, Tom; Enright, John

    2014-01-01

    The performance of a star tracker is largely based on the availability of its attitude solution. Several methods exist to assess star tracker availability under both static and dynamic imaging conditions. However, these methods typically make various idealizations that can limit the accuracy of these results. This study aims to increase the fidelity of star tracker availability modeling by accounting for the effects of detection logic and pixel saturation on star detection. We achieve this by developing an analytical model for the focal plane intensity distribution of a star in the presence of sensor slew. Using the developed model, we examine the effects of slew rate on star detection using simulations and lab tests. The developed approach allows us to determine the maximum slew rate for which a star of a given stellar magnitude can still be detected. This information can then be used to describe the availability of a star tracker attitude solution as a function of slew rate, both spatially, across the entire celestial sphere, or locally, along a specified orientation track. PMID:24577522

  8. Ground Testing Strategies for Verifying the Slew Rate Tolerance of Star Trackers

    Directory of Open Access Journals (Sweden)

    Tom Dzamba

    2014-02-01

    Full Text Available The performance of a star tracker is largely based on the availability of its attitude solution. Several methods exist to assess star tracker availability under both static and dynamic imaging conditions. However, these methods typically make various idealizations that can limit the accuracy of these results. This study aims to increase the fidelity of star tracker availability modeling by accounting for the effects of detection logic and pixel saturation on star detection. We achieve this by developing an analytical model for the focal plane intensity distribution of a star in the presence of sensor slew. Using the developed model, we examine the effects of slew rate on star detection using simulations and lab tests. The developed approach allows us to determine the maximum slew rate for which a star of a given stellar magnitude can still be detected. This information can then be used to describe the availability of a star tracker attitude solution as a function of slew rate, both spatially, across the entire celestial sphere, or locally, along a specified orientation track.

  9. The use of a second generation star tracker in the control loop of the pointing system

    DEFF Research Database (Denmark)

    Betto, Maurizio

    1998-01-01

    The scope of this note is to propose the use of a second generation star tracker to guide the UVISS pointing system.As UVISS is mounted on the International Space Station the time to observe a specific star is limited by the orbital motion, therefore it is crucial to reduce as much as possible...

  10. Determining the Requirements for the Star Tracker on JEM-EUSO

    OpenAIRE

    Dhraief, Youssef; Hedayati, Farid

    2015-01-01

    This work will focus on how the JEM-EUSO project, which orbits around Earth on the International Space Station and whose purpose is to detect air shower from the atmosphere caused by high energy particles from outer space, will be able to determine its positon once it detects such air shower. This is best done by adding a star tracker to it. The main purpose is to determine how accurate the star tracker has to be. To do this a few calculations were made, as well as looking for any star tracke...

  11. The STAR silicon vertex tracker: a large area silicon drift detector

    CERN Document Server

    Lynn, D; Beuttenmüller, Rolf H; Caines, H; Chen, W; Dimassimo, D; Dyke, H; Elliot, D; Eremin, V; Grau, M; Hoffmann, G W; Humanic, T; Ilyashenko, Yu S; Kotov, I; Kraner, H W; Kuczewski, P; Leonhardt, B; Li, Z; Liaw, C J; Lo Curto, G; Middelkamp, P; Minor, R; Munhoz, M; Ott, G; Pandey, S U; Pruneau, C A; Rykov, V L; Schambach, J; Sedlmeir, J; Soja, B; Sugarbaker, E R; Takahashi, J; Wilson, K; Wilson, R

    2000-01-01

    The Solenoidal Tracker At RHIC-Silicon Vertex Tracker (STAR-SVT) is a three barrel microvertex detector based upon silicon drift detector technology. As designed for the STAR-SVT, silicon drift detectors (SDDs) are capable of providing unambiguous two-dimensional hit position measurements with resolutions on the order of 20 mu m in each coordinate. Achievement of such resolutions, particularly in the drift direction coordinate, depends upon certain characteristics of silicon and drift detector geometry that are uniquely critical for silicon drift detectors hit measurements. Here we describe features of the design of the STAR-SVT SDDs and the front-end electronics that are motivated by such characteristics.

  12. Star Tracker Attitude Estimation for an Indoor Ground-Based Spacecraft Simulator

    OpenAIRE

    Tappe, J.; Kim, J.J.; A. Jordan; Agrawal, B.N.

    2011-01-01

    The article of record as published may be found at http://dx.doi.org/10.2514/6.2011-6270 This paper presents a study of star tracker attitude estimation algorithms and implementation on an indoor ground-based Three Axis Spacecraft Simulator (TASS). Angle, Planar Triangle, and Spherical Triangle algorithms are studied for star pattern recognition. Least squares, QUEST and TRIAD algorithms are studied for attitude determination. A star field image is suspended above TASS. The indoor laborato...

  13. Low-frequency Periodic Error Identification and Compensation for Star Tracker Attitude Measurement

    Institute of Scientific and Technical Information of China (English)

    WANG Jiongqi; XIONG Kai; ZHOU Haiyin

    2012-01-01

    The low-frequency periodic error of star tracker is one of the most critical problems for high-accuracy satellite attitude determination.In this paper an approach is proposed to identify and compensate the low-frequency periodic error for star tracker in attitude measurement.The analytical expression between the estimated gyro drift and the low-frequency periodic error of star tracker is derived firstly.And then the low-frequency periodic error,which can be expressed by Fourier series,is identified by the frequency spectrum of the estimated gyro drift according to the solution of the first step.Furthermore,the compensated model of the low-frequency periodic error is established based on the identified parameters to improve the attitude determination accuracy.Finally,promising simulated experimental results demonstrate the validity and effectiveness of the proposed method.The periodic error for attitude determination is eliminated basically and the estimation precision is improved greatly.

  14. Operations of a non-stellar object tracker in space

    OpenAIRE

    Riis, Troels; Jørgensen, John Leif; Betto, Maurizio

    1999-01-01

    The ability to detect and track non-stellar objects by utilizing a star tracker may seem rather straight forward, as any bright object, not recognized as a star by the system is a non stellar object. However, several pitfalls and errors exist, if a reliable and robust detection is required. To test the operation, performance and robustness of such a function, the Autonomous Vision System (AVS), a fully autonomous star tracker that has flown onboard the Teamsat was equipped with several advanc...

  15. Magnitude calibration of a fixed head star tracker using Astro-1 flight data

    Science.gov (United States)

    Rakoczy, John M.; West, Mark E.

    1992-01-01

    The Astro-1 UV astronomy mission was hampered by the failures of the automatic star acquisition procedure. The acquisition procedure depended on the Instrument Pointing Subsystem's Fixed Head Star Trackers (FHST) to acquire, track and identify guidestars of known visual magnitude. During the Astro-1 mission it was suspected that the star magnitudes measured by the FHST were much lower than predicted. A postflight investigation of the Astro-1 flight data confirmed and quantified this suspicion. Star magnitude calibration curves computed from the flight data depict the variance from the preflight calibration curves. These results are helping engineers to plan improvements to the acquisition procedure for the upcoming Astro-2 mission.

  16. Application of flight data to Space Shuttle CCD star tracker catalog design

    Science.gov (United States)

    Barry, Karen; Hindman, Mark; Yates, Russell

    1993-01-01

    The new Shuttle Solid-State Tracker (SSST) is an improved but transparent replacement for the analog version which has flown on every Shuttle mission. This paper will examine the data collected from four Shuttle flights to establish parameters for selection of acceptable navigation stars, and apply those parameters to establish a star catalog which will be sufficient to ensure the ability of the SSST to perform attitude updates while docked to the Space Station.

  17. The AeroAstro Fast-Angular-Rate Miniature Star Tracker: Algorithms and Simulation Results

    OpenAIRE

    Seng, Bill; Stafford, James; Zenick, Ray; Kennedy, Vickie

    2005-01-01

    AeroAstro’s Fast Angular Rate Miniature Star Tracker (FAR-MST) is an optical-based system that uses image processing of star fields viewed from the satellite to determine ephemeris information. The FAR-MST system offers solutions to several problems, including the determination of an initial position fix (the “lost-in-space” problem), determination of spacecraft attitude, and measurement of spacecraft rotational velocity – even at high angular rates. Low-cost, high-performance microsatellites...

  18. Design and Performance Evaluation of an Intelligent Star Tracker

    OpenAIRE

    Clark, Natalie

    2001-01-01

    Current state-of-the-art commercial star sensors typically weigh 15 pounds, attain 5 to 10 arcsecond accuracy, and use roughly 10 watts of power. Unfortunately, the current state-of-the-art commercial star sensors do not meet many of NASA’s “next-generation” spacecraft and instrument needs. Nor do they satisfy Air Force’s needs for micro/nano-satellite systems. In an effort to satisfy micro/nano satellite mission needs the Air Force Research Laboratory is developing an intelligent star Tracke...

  19. Prospects for observing pulsating red giants with the MONS Star Trackers

    CERN Document Server

    Bedding, T R

    2000-01-01

    K and M giants show variability on timescales from years down to days and possibly even hours. I discuss the contribution that can be made with high-precision photometry that will be obtained by the MONS Star Trackers. These include observations of flare-like events on Mira variables, and oscillation spectra for K giants and short-period M giants.

  20. Star tracker axis-to-sunlit earth horizon angle constraint evaluations for rendezvous operations

    Science.gov (United States)

    Hutchison, W. L.

    1975-01-01

    The results are presented of a study initiated to evaluate the star tracker axis-to-sunlit earth horizon angle constraint with respect to limitations imposed on the passive target rendezvous capability. The data presented include considerations for dispersions and sensor pointing capabilities and generalizations with respect to the uncertainties associated with the angle constraint available in practice.

  1. StarTracker: An Integrated, Web-based Clinical Search Engine

    OpenAIRE

    Gregg, William; Jirjis, Jim; Lorenzi, Nancy M.; Giuse, Dario

    2003-01-01

    This poster details the design and use of the StarTracker clinical search engine. This program is fully integrated within our electronic medical record system and allows users to enter simple rules that direct formatted searches of multiple legacy databases.

  2. Exploring the possibilities for star-tracker assisted calibration of the six individual GOCE accelerometers

    NARCIS (Netherlands)

    Visser, P.N.A.M.

    2008-01-01

    A method has been developed and tested for estimating calibration parameters for the six accelerometers on board the Gravity field and steady-state Ocean Circulation Explorer (GOCE) from star tracker observations. These six accelerometers are part of the gradiometer, which is the prime instrument on

  3. The Forward GEM Tracker of STAR at RHIC

    OpenAIRE

    Simon, F.; Balewski, J.; Fatemi, R.; Hasell, D.; Kelsey, J.; Majka, R.; Page, B.; Plesko, M.; Underwood, D.; Smirnov, N.; Sowinski, J.; Spinka, H.; Surrow, B.(Temple University, Philadelphia, PA, 19122, USA); Visser, G.

    2008-01-01

    The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) is in the process of designing and constructing a forward tracking system based on triple GEM technology. This upgrade is necessary to give STAR the capability to reconstruct and identify the charge sign of W bosons over an extended rapidity range through their leptonic decay mode into an electron (positron) and a neutrino. This will allow a detailed study of the flavor-separated spin str...

  4. CMOS Active Pixel Sensor Star Tracker with Regional Electronic Shutter

    Science.gov (United States)

    Yadid-Pecht, Orly; Pain, Bedabrata; Staller, Craig; Clark, Christopher; Fossum, Eric

    1996-01-01

    The guidance system in a spacecraft determines spacecraft attitude by matching an observed star field to a star catalog....An APS(active pixel sensor)-based system can reduce mass and power consumption and radiation effects compared to a CCD(charge-coupled device)-based system...This paper reports an APS (active pixel sensor) with locally variable times, achieved through individual pixel reset (IPR).

  5. Star tracker based attitude determination system for nanosatellites

    OpenAIRE

    Jané Abad, Jaume

    2015-01-01

    The aim of this project is to conceive, design, implement, test, qualify, operate, and validate a new high accuracy sensor based on a star sensor for the ADCS subsystem of the 3Cat-2 Mission. This system will implement the necessary algorithms for the star identification and attitude determination in a highly constrained in time, size, mass and power embedded environment. Test and qualification campaign shall be done both in controlled environment and field test. [ANGLÈS] Access to space i...

  6. General constraints on influential error sources for super-high accuracy star tracker

    CERN Document Server

    Zhang, J; Wang, L; Long, Y

    2015-01-01

    Though in-orbit calibration is adopted to reduce position error of individual star spot down to 0.02pixel on star tracker, little study has been conducted on the accuracy to what extent for some significant error sources which often leads to in-orbit correction inefficiency. This study presents the general theory and estimates of the minimum error constraints, including not only on position but also on intensity and scale of Gaussian shaped profile based on Cramer Rao Lower Bound(CRLB) theory. By imposing those constraints on motion, drift in focal length and so on, margins of in-flight error sources and the final accuracy of star tracker can be analytically determined before launch.

  7. Deep coupling of star tracker and MEMS-gyro data under highly dynamic and long exposure conditions

    International Nuclear Information System (INIS)

    Star trackers and gyroscopes are the two most widely used attitude measurement devices in spacecrafts. The star tracker is supposed to have the highest accuracy in stable conditions among different types of attitude measurement devices. In general, to detect faint stars and reduce the size of the star tracker, a method with long exposure time method is usually used. Thus, under dynamic conditions, smearing of the star image may appear and result in decreased accuracy or even failed extraction of the star spot. This may cause inaccuracies in attitude measurement. Gyros have relatively good dynamic performance and are usually used in combination with star trackers. However, current combination methods focus mainly on the data fusion of the output attitude data levels, which are inadequate for utilizing and processing internal blurred star image information. A method for tracking deep coupling stars and MEMS-gyro data is proposed in this work. The method achieves deep fusion at the star image level. First, dynamic star image processing is performed based on the angular velocity information of the MEMS-gyro. Signal-to-noise ratio (SNR) of the star spot could be improved, and extraction is achieved more effectively. Then, a prediction model for optimal estimation of the star spot position is obtained through the MEMS-gyro, and an extended Kalman filter is introduced. Meanwhile, the MEMS-gyro drift can be estimated and compensated though the proposed method. These enable the star tracker to achieve high star centroid determination accuracy under dynamic conditions. The MEMS-gyro drift can be corrected even when attitude data of the star tracker are unable to be solved and only one navigation star is captured in the field of view. Laboratory experiments were performed to verify the effectiveness of the proposed method and the whole system. (paper)

  8. Star Tracker Algorithms and a Low-Cost Attitude Determination and Control System for Space Missions

    OpenAIRE

    Delabie, Tjorven

    2016-01-01

    The attitude determination and control system determines and controls the orientation of the spacecraft. This system is crucial in the majority of space missions to e.g. point a camera to a star or direct an antenna to a ground station. Increasingly complex missions drive the need for higher accuracy, while the growing number of small spacecraft requires high robustness and low computational cost. This work focusses on the star tracker, a sensor that takes an image of the stars and compares i...

  9. Glas Spacecraft Attitude Determination Using CCD Star Tracker and 3-AXIS Gyros

    Science.gov (United States)

    Bae, Sungkoo

    The main purpose of the Geoscience Laser Altimeter System (GLAS) is to determine the mass balance of the polar ice-sheets and their contributions to global sea level change. For the mission, the required accuracy for the laser altimeter height measurements is 10 cm. In this case, the direction in which the altimeter beam is pointing relative to the Terrestrial Reference Frame must be known to an accuracy of 1.5 arcseconds assuming the average slope of the ice-sheet surface is one degree. The laser pointing direction will be determined relative to the star field measured by a star tracker in the GLAS spacecraft (ICESAT). Thus, the specification of one arcsecond pointing accuracy requires that the spacecraft attitude determination has comparable accuracy. A Charge Coupled Device (CCD) star tracker and gyros will be installed in an optical bench of ICESAT to determine the spacecraft attitude. Each star position measurement from the CCD star tracker contains approximately five arcseconds position uncertainty depending on the magnitude of the observed stars. Furthermore, gyro output accuracy is corrupted by measurement noise and bias. The main purpose of this dissertation was to investigate the ability to determine the attitude to better than one arcsecond (1σ) using developed estimation algorithms. Extended Kalman Filters and a Batch method were developed and used to estimate the simulated GLAS attitude. The determined attitude showed that the root sum square of roll and pitch errors, which directly affect the laser beam pointing error, reduced to about 0.5 arcsecond (1σ), far better than one arcsecond. In order to support the study result, actual attitude data obtained from the X-ray Timing Explorer spacecraft, were processed with some of algorithms developed for this research. As a part of the generation of the measurement data, a star identification algorithm was developed.

  10. Performance of the Star Tracker Lightshades on the Earth Observing Satellite (EOS) Aqua

    Science.gov (United States)

    Kenney, Thomas; Schroeder, Michael; Donnelly, Michael; McNally, Mark; Bauer, Frank H. (Technical Monitor)

    2003-01-01

    The TRW built EOS Aqua spacecraft uses two Ball Aerospace CT-602 star trackers to provide attitude updates to the 3-axis, zero momentum, controller. Two months prior to the scheduled launch of Aqua, Ball reported an error in the design of the star tracker lightshades. The lightshades, which had been designed specifically for the EOS Common spacecraft, were not expected to meet the stray light rejection requirements of the mission and thus impact the overall spacecraft pointing performance. What ensued was an effort to characterize the actual performance of the existing shade design, determine what could be done within the physical envelope available, and modify the hardware to meet requirements. Changes were made based on this review activity and Aqua was launched on May 4, 2002. To date the spacecraft is meeting all of its science pointing requirements. Reported here are the lightshade design predictions, test results, and the measured on orbit performance of these shades.

  11. Triple GEM Detectors for the Forward Tracker in STAR

    CERN Document Server

    Simon, Frank; Kohl, Michael; Majka, Richard; Plesko, Miroslav; Underwood, David; Sakuma, Tai; Smirnov, Nikolai; Spinka, Harold; Surrow, Bernd

    2007-01-01

    Future measurements of the flavor-separated spin structure of the proton via parity-violating W boson production at RHIC require an upgrade of the forward tracking system of the STAR detector. This upgrade will allow the reconstruction of the charge sign of electrons and positrons produced from decaying W bosons. A design based on six large area triple GEM disks using GEM foils produced by Tech-Etch Inc. has emerged as a cost-effective solution to provide the necessary tracking precision. We report first results from a beam test of three test detectors using Tech-Etch produced GEM foils and a laser etched two dimensional strip readout. The detectors show good operational stability, high efficiency and a spacial resolution of around 70 um or better, exceeding the requirements for the forward tracking upgrade. The influence of the angle of incidence of the particles on the spatial resolution of the detectors has also been studied in detail.

  12. Apollo Telescope Mount (ATM) gimballed star tracker. [developed for the Skylab program

    Science.gov (United States)

    Lana, J. D.

    1974-01-01

    Design and development of six gimballed star trackers for Skylab's Apollo Telescope Mount, which performed successfully on all three manned Skylab missions and accumulated a total usage time of approximately 3,500 hours, is described in terms of configurations, materials and construction, qualification testing, performance, and reliability characteristics. A brief program history and design changes incorporated during the life of the program are also discussed. Extensive drawings, block diagrams, and photographs are provided.

  13. Success by 1000 Improvements: Flight Qualification of the ST-16 Star Tracker

    OpenAIRE

    Dzamba, Tom; Enright, John; Sinclair, Doug; Amankwah, Kofi; Votel, Ronny; Jovanovic, Ilija; McVittie, Geoffrey

    2014-01-01

    The first launch of a pair of 90 gram Sinclair Interplanetary ST-16 star trackers was in November, 2013 on-board the Skybox Imaging SkySat-1 satellite. The sensor performance — as captured by the sensors’ availability, accuracy, and bad-match rate — fell significantly below expectations. This paper explores the flight qualification campaign undertaken by the sensor developers to bring the sensors back to their intended level of performance. No single fix was sufficient and many small incremen...

  14. Optical analysis of the star-tracker telescope for Gravity Probe

    Science.gov (United States)

    Zissa, D. E.

    1984-01-01

    A ray tracing modeling of the star tracker telescope for Gravity Probe was used to predict the character of the output signal and its sensitivity to fabrication errors. In particular, the impact of the optical subsystem on the requirement of 1 milliarc second signal linearity over a + or - 50 milliarc second range was examined. Photomultiplier and solid state detector options were considered. Recommendations are made.

  15. Exploring the possibilities for star-tracker assisted calibration of the six individual GOCE accelerometers

    OpenAIRE

    Visser, P N A M

    2008-01-01

    A method has been developed and tested for estimating calibration parameters for the six accelerometers on board the Gravity field and steady-state Ocean Circulation Explorer (GOCE) from star tracker observations. These six accelerometers are part of the gradiometer, which is the prime instrument on board GOCE. It will be shown that by taking appropriate combinations of observations collected by the accelerometers, by modeling acceleration terms caused by gravity gradients from an a priori lo...

  16. Autonomous attitude estimation via star sensing and pattern recognition

    Science.gov (United States)

    Junkins, J. L.; Strikwerda, T. E.

    1979-01-01

    Results are reported on the development of an autonomous, onboard, near real time spacecraft attitude estimation technique. The approach uses CCD based star sensors to digitize relative star positions. Three microcomputers are envisioned, configured in parallel, to: (1) determine star image centroids and delete spurious images; (2) identify measured stars with stars in an onboard catalog and determine discrete attitude estimates; (3) integrate gyro rate measurements and determine optimal real time attitude estimates for use in the control system and for feedback to the star identification algorithm. Algorithms for the star identification are presented. The discrete attitude estimation algorithm recovers thermally varying interlock angles between two star sensors. The optimal state estimation process recovers rate gyro biases in addition to real time attitude estimates.

  17. Reducing systematic centroid errors induced by fiber optic faceplates in intensified high-accuracy star trackers.

    Science.gov (United States)

    Xiong, Kun; Jiang, Jie

    2015-01-01

    Compared with traditional star trackers, intensified high-accuracy star trackers equipped with an image intensifier exhibit overwhelmingly superior dynamic performance. However, the multiple-fiber-optic faceplate structure in the image intensifier complicates the optoelectronic detecting system of star trackers and may cause considerable systematic centroid errors and poor attitude accuracy. All the sources of systematic centroid errors related to fiber optic faceplates (FOFPs) throughout the detection process of the optoelectronic system were analyzed. Based on the general expression of the systematic centroid error deduced in the frequency domain and the FOFP modulation transfer function, an accurate expression that described the systematic centroid error of FOFPs was obtained. Furthermore, reduction of the systematic error between the optical lens and the input FOFP of the intensifier, the one among multiple FOFPs and the one between the output FOFP of the intensifier and the imaging chip of the detecting system were discussed. Two important parametric constraints were acquired from the analysis. The correctness of the analysis on the optoelectronic detecting system was demonstrated through simulation and experiment. PMID:26016920

  18. Reducing Systematic Centroid Errors Induced by Fiber Optic Faceplates in Intensified High-Accuracy Star Trackers

    Directory of Open Access Journals (Sweden)

    Kun Xiong

    2015-05-01

    Full Text Available Compared with traditional star trackers, intensified high-accuracy star trackers equipped with an image intensifier exhibit overwhelmingly superior dynamic performance. However, the multiple-fiber-optic faceplate structure in the image intensifier complicates the optoelectronic detecting system of star trackers and may cause considerable systematic centroid errors and poor attitude accuracy. All the sources of systematic centroid errors related to fiber optic faceplates (FOFPs throughout the detection process of the optoelectronic system were analyzed. Based on the general expression of the systematic centroid error deduced in the frequency domain and the FOFP modulation transfer function, an accurate expression that described the systematic centroid error of FOFPs was obtained. Furthermore, reduction of the systematic error between the optical lens and the input FOFP of the intensifier, the one among multiple FOFPs and the one between the output FOFP of the intensifier and the imaging chip of the detecting system were discussed. Two important parametric constraints were acquired from the analysis. The correctness of the analysis on the optoelectronic detecting system was demonstrated through simulation and experiment.

  19. General constraints on influential error sources for super-high accuracy star tracker

    OpenAIRE

    Zhang, J.; Hao, Y. C.; Wang, L.; Long, Y

    2015-01-01

    Though in-orbit calibration is adopted to reduce position error of individual star spot down to 0.02pixel on star tracker, little study has been conducted on the accuracy to what extent for some significant error sources which often leads to in-orbit correction inefficiency. This study presents the general theory and estimates of the minimum error constraints, including not only on position but also on intensity and scale of Gaussian shaped profile based on Cramer Rao Lower Bound(CRLB) theory...

  20. 新型分体式星敏感器设计及其应用%Design and applications of novel separated type star tracker

    Institute of Scientific and Technical Information of China (English)

    钟红军; 卢欣; 李春江; 李玉明; 李晓

    2014-01-01

    星敏感器是当前广泛应用于航天器姿态测量的高精度光学姿态敏感器。介绍了一种新型分体式星敏感器的总体设计、应用及验证情况,其已成功应用于科学试验、通讯及地球观测等多种卫星平台,共有21套产品在轨验证。根据在轨遥测数据分析,全面验证了其主要技术指标:探测灵敏度5.7 Mv、数据更新率8 Hz、测量精度2.6″、阳光抑制角28°、动态性能1(°)/s等。新型分体式星敏感器是国际上首个在轨飞行验证并引入控制系统闭环控制的APS星敏感器,根据地面测试验证结果和20余套产品长达两年在轨数据的全面分析,其在轨性能与地面测试性能一致,在轨测试结果证明产品的测量精度、鲁棒性、可用性和可靠性等主要性能满足卫星使用要求。%Star tracker is current widely used optical sensor in spacecraft attitude control system which produces the most accurate measurements. The overall design description, application and qualification results of a novel separated autonomous miniature star tracker were introduced. The novel separated type star tracker successfully operated in-orbit on a large variety of different satellite platforms such as scientific experiment, telecommunication and earth observation. The novel star tracker has applied in-orbit with a total of 21 sets of products up to now. According to the real time telemetry data packages under real in-orbit conditions, the main qualification features are sensitivity 5.7 Mv, update rate 8 Hz, accuracy 2.6″, sun exclusion 28° , tracking slew rate 1 (° )/s. The novel separated type star tracker was the first APS based star tracker ever flown which was adopted in AOCS closed loop control. A full analysis on ground qualification campaign was carried out successfully on the novel star tracker and an in-flight qualification was also achieved, with more than two years information from 20 other star trackers on

  1. Fixed-head star tracker attitude updates on the Hubble Space Telescope

    Science.gov (United States)

    Nadelman, Matthew S.; Karl, Jeffrey B.; Hallock, Lou

    1994-01-01

    The Hubble Space Telescope (HST) was launched in April 1990 to begin observing celestial space to the edge of the universe. National Aeronautics and Space Administration (NASA) standard fixed-head star trackers (FHST's) are used operationally onboard the HST to regularly adjust ('update') the spacecraft attitude before the acquisition of guide stars for science observations. During the first 3 months of the mission, the FHST's updated the spacecraft attitude successfully only 85 percent of the time. During the other periods, the trackers were unable to find the selected stars -- either they failed to find any star, or worse, they selected incorrect stars and produced erroneous attitude updates. In July 1990, the HST project office at Goddard Space Flight Center (GSFC) requested that Computer Sciences Corporation (CSC) form an investigative 'tiger' team to examine these FHST update failures. This paper discusses the work of the FHST tiger team, describes the investigations that led the team to identify the sources of the errors, and defines the solutions that were subsequently developed, which ultimately increased the success rate of FHST updates to approximately 98 percent.

  2. (abstract) Realization of a Faster, Cheaper, Better Mission and Its New Paradigm Star Tracker, the Advanced Stellar Compass

    Science.gov (United States)

    Eisenman, Allan Read; Liebe, Carl Christian; Joergensen, John Lief; Jensen, Gunnar Bent

    1997-01-01

    The first Danish satellite, rsted, will be launched in August of 1997. The scientific objective of sted is to perform a precision mapping of the Earth's magnetic field. Attitude data for the payload and the satellite are provided by the Advanced Stellar Compass (ASC) star tracker. The ASC consists of a CCD star camera and a capable microprocessor which operates by comparing the star image frames taken by the camera to its internal star catalogs.

  3. Fixed-head star tracker magnitude calibration on the solar maximum mission

    Science.gov (United States)

    Pitone, Daniel S.; Twambly, B. J.; Eudell, A. H.; Roberts, D. A.

    1990-01-01

    The sensitivity of the fixed-head star trackers (FHSTs) on the Solar Maximum Mission (SMM) is defined as the accuracy of the electronic response to the magnitude of a star in the sensor field-of-view, which is measured as intensity in volts. To identify stars during attitude determination and control processes, a transformation equation is required to convert from star intensity in volts to units of magnitude and vice versa. To maintain high accuracy standards, this transformation is calibrated frequently. A sensitivity index is defined as the observed intensity in volts divided by the predicted intensity in volts; thus, the sensitivity index is a measure of the accuracy of the calibration. Using the sensitivity index, analysis is presented that compares the strengths and weaknesses of two possible transformation equations. The effect on the transformation equations of variables, such as position in the sensor field-of-view, star color, and star magnitude, is investigated. In addition, results are given that evaluate the aging process of each sensor. The results in this work can be used by future missions as an aid to employing data from star cameras as effectively as possible.

  4. A high-accuracy digital star tracker for advanced planetary missions

    Science.gov (United States)

    Salomon, P. M.; Crawford, W. E.

    1973-01-01

    The digital star tracker represents a novel departure from previous analog designs in terms of circuit implementation and operational capabilities. As an element of an all-digital spacecraft control system, it combines proven low-level analog signal processing with digital error control and command functions. Additional capabilities that are obtainable with the digital circuitry include programmable intensity threshold gates, commanded electronic pointing control, and an acquisition/control algorithm which minimizes the effects of straylight disturbances. The capabilities inherent in the implementation have been successfully demonstrated in a laboratory model of the instrument.

  5. LLiST - a new star tracker camera for tip-tilt correction at IOTA

    OpenAIRE

    Schuller, P.A.; Lacasse, M. G.; Lydon, D.; McGonagle, W. H.; Pedretti, E; Reich, R. K.; Schloerb, F. P.; Traub, W. A.

    2004-01-01

    The tip-tilt correction system at the Infrared Optical Telescope Array (IOTA) has been upgraded with a new star tracker camera. The camera features a backside-illuminated CCD chip offering doubled overall quantum efficiency and a four times higher system gain compared to the previous system. Tests carried out to characterize the new system showed a higher system gain with a lower read-out noise electron level. Shorter read-out cycle times now allow to compensate tip-tilt fluctuations so that ...

  6. STR: a student developed star tracker for the ESA-LED ESMO moon mission

    OpenAIRE

    Lizy-Destrez, Stéphanie; Mimoun, David

    2010-01-01

    In the frame of their engineering degree, ISAE’s students are developing a Star Tracker, with the aim of being the core attitude estimation equipment of the European Moon Student Orbiter. This development goes on since several years and is currently in phase B. We intend to start building an integrated breadboard for the end of the academic year. The STR is composed of several sub-systems: the optical and detection sub-system, the electronics, the mechanics and the software. The optical de...

  7. LLiST - a new star tracker camera for tip-tilt correction at IOTA

    CERN Document Server

    Schuller, P A; Lydon, D; McGonagle, W H; Pedretti, E; Reich, R K; Schloerb, F P; Traub, W A

    2004-01-01

    The tip-tilt correction system at the Infrared Optical Telescope Array (IOTA) has been upgraded with a new star tracker camera. The camera features a backside-illuminated CCD chip offering doubled overall quantum efficiency and a four times higher system gain compared to the previous system. Tests carried out to characterize the new system showed a higher system gain with a lower read-out noise electron level. Shorter read-out cycle times now allow to compensate tip-tilt fluctuations so that their error imposed on visibility measurements becomes comparable to, and even smaller than, that of higher-order aberrations.

  8. Development of the Pico Star Tracker ST-200 – Design Challenges and Road Ahead

    OpenAIRE

    Segert, Tom; Engelen, Steven; Buhl, Matthias; Monna, Bert

    2011-01-01

    The Pico Star Tracker ST-200 under development by Berlin Space Technologies GmbH (BST) is specifically designed keeping the limitations of CubeSats in mind. It comes in a compact 29x29x37mm³ package. It weights 74g and has a power consumption of 220mW average (620mW peak). The ST-200 offers a set of standard interfaces (I²C, SPI, RS485, RS232) and accepts input voltages of 3.3 to 5V. It can detect stars with a limiting magnitude of 6 and has an accuracy of 30 arc seconds (~0.01°). Using its i...

  9. Theoretic Studies of Full Constraints on a Star Tracker's Influential Error Sources for In-orbit Calibration

    Science.gov (United States)

    Zhang, Jun; Cai Hao, Yun; Wang, Li; Long, Ye

    2016-03-01

    To collect star transits data qualified for in-orbit calibration, this study derives the full error constraints to limit star tracker's influential error sources and computes their error boundaries from a theoretical perspective. The full constraints, including not only the minimum variance estimation of position but also the error bound prediction of scale and intensity of Gaussian-shaped starspots, are studied based on the Cramér-Rao Lower Bound (CRLB) theorem. By imposing these constraints on motion, drift in focal length, and other factors, their boundaries could be determined before launch. Therefore, the in-orbit correction accuracy is expected to be close to CRLB through suitable implementation of these constraints. The correctness of the theoretical position error of motion is demonstrated by the data-fitting procedure against test results of star tracker on dynamic performance. The simulation result shows that the drift in focal length can generate an error with the same magnitude as detector noise and thus might be the dominant error source when star tracker is working under stationary circumstance. Using the accuracy performance of some typical star trackers, this study shows that the CRLB constraint may be very effective to estimate the overall position error of a starspot or one axis, valuable data that can be used for online calibration. The overall position uncertainty analysis shows that a weighted method can be employed for calibration, a process where star data can be given a weight in inverse proportion to the CRLB value.

  10. Color/magnitude calibration for National Aeronautics and Space Administration (NASA) standard Fixed-Head Star Trackers (FHST)

    Science.gov (United States)

    Landis, J.; Leid, Terry; Garber, A.; Lee, M.

    1994-01-01

    This paper characterizes and analyzes the spectral response of Ball Aerospace fixed-head star trackers, (FHST's) currently in use on some three-axis stabilized spacecraft. The FHST output is a function of the frequency and intensity of the incident light and the position of the star image in the field of view. The FHST's on board the Extreme Ultraviolet Explorer (EUVE) have had occasional problems identifying stars with a high B-V value. These problems are characterized by inaccurate intensity counts observed by the tracker. The inaccuracies are due to errors in the observed star magnitude values. These errors are unique to each individual FHST. For this reason, data were also collected and analyzed from the Upper Atmosphere Research Satellite (UARS). As a consequence of this work, the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) hopes to improve the attitude accuracy on these missions and to adopt better star selection procedures for catalogs.

  11. Studies on dynamic motion compensation and positioning accuracy on star tracker.

    Science.gov (United States)

    Jun, Zhang; Yuncai, Hao; Li, Wang; Da, Liu

    2015-10-01

    Error from motion is the dominant restriction on the improvement of dynamic performance on a star tracker. As a remarkable motion error, the degree of nonuniformity of the star image velocity field on the detector is studied, and thus a general model for the moving star spot is built. To minimize velocity nonuniformity, a novel general method is proposed to derive the proper motion compensation and location accuracy in cases of both uniform velocity and acceleration. Using this method, a theoretic analysis on the accuracy of time-delayed integration and similar techniques, which are thought of as state-of-the-art approaches to reduce error from motion, is conducted. The simulations and experimental results validate the proposed method. Our method shows a more steady performance than the dynamic binning algorithm. The positional error could be neglected when the smear length is far less than 3.464 times the scale of star spot, which suggests accuracy can be maintained by changing frame-integration time inverse proportional to the velocity on the focal plane. It also shows that the acceleration effect must be compensated to achieve accuracy close to the Cramér-Rao lower bound. PMID:26479618

  12. Simulation on the Charged Particle Response of the STAR Heavy Flavor Tracker Pixel Detector

    Science.gov (United States)

    Cimaroli, Alex; Li, Xin

    2009-10-01

    The main task of the STAR experiment, located at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory, is to study the quark-gluon plasma (QGP), which is believed to have been created a few microseconds after the ``Big Bang.'' Heavy quarks are ideal tools for studying the properties of QGP. The Heavy Flavor Tracker (HFT) is the central part of the STAR future heavy flavor physics program and will enable STAR to directly measure heavy flavor mesons. The core of HFT is a pixel detector (PIXEL) using CMOS Active PIXEL Sensor. This poster will describe the development of a detailed simulation of the pixel detector response to charged particles and the corresponding fast simulation that dramatically enhances the simulation speed with little sacrifice in accuracy. The full simulation randomly generates ionized electrons along an incoming track and diffuses the electrons inside the pixel array until they are collected by the electronics or recombined inside a pixel. With the same result, the fast simulation, which quickens processing time from one hour to 5 seconds, generates a grid inside a single pixel and create a map of probability distribution functions for a single ionized electron generated from a grid point. We will also discuss the study of pixel detector position resolution using a simple clustering algorithm.

  13. Test of charge injection device, phase 1. [prospective star tracker application

    Science.gov (United States)

    Gradinger, A.; Sayles, M. B.; Peters, D.; Buckley, P.

    1981-01-01

    A computer-controlled automatic facility containing two interactive microprocessors, peripherals, and an optical bench was used to obtain device characteristics for use in evaluating CID's as the sensor element in a prospective star tracker application. Each of the ST-256 chips tested contains a 256 x 256 pixel element array with 65536 picture elements. Two ST-256 devices were tested at 20 C under light levels of 10%, 0.1%, and 0.01% saturation, and in darkness. The saturation level was established at 0.95 microwatts sq cm as measured by the radiometeric sensor. Two test runs under each condition were performed for each chip. Two complete sets of data for each of the devices were thus obtained. A separate data field was used to store the results of each test condition. Repetitive runs of a test condition were stored sequentially in the same file. Examination of the data using print-outs is shown in examples.

  14. Analysis for Mar Vel Black and acetylene soot low reflectivity surfaces for star tracker sunshade applications

    Science.gov (United States)

    Yung, E.

    1974-01-01

    Mar Vel Black is a revolutionary new extremely low reflectivity anodized coating developed by Martin Marietta of Denver. It is of great interest in optics in general, and in star trackers specifically because it can reduce extraneous light reflections. A sample of Mar Vel Black was evaluated. Mar Vel Black looks much like a super black surface with many small peaks and very steep sides so that any light incident upon the surface will tend to reflect many times before exiting that surface. Even a high reflectivity surface would thus appear to have a very low reflectivity under such conditions. Conversely, acetylene soot does not have the magnified surface appearance of a super black surface. Its performance is, however, predictable from the surface structure, considering the known configuration of virtually pure carbon.

  15. A study of a multi-pinned phase CCD detector for use as a star tracker

    Science.gov (United States)

    Friedman, Scott D.

    1994-01-01

    This grant has supported studies of the use of charge coupled devices (CCD's) in star trackers in a number of different areas. Among the tasks we have pursued are the following: (1) radiation modeling and the increase in noise equivalent angle as a result of exposure to protons and bremsstrahlung gamma rays; (2) the development of pattern matching software to identify field locations from a CCD image and a pre-existing map of the local area; (3) observations of various stellar fields from the 24 inch telescope at the Offit Observatory at JHU, primarily to test the pattern matching software (these included crowded fields as well as moving objects, like comets); and (4) tracking of very faint objects to determine the faint limit of the CCD system.

  16. Star tracker constraint violations digital capability description and analysis results. Mission planning, mission analysis, and software formulation

    Science.gov (United States)

    Poston, P. L.

    1975-01-01

    Results of star tracker constraint violation analyses performed with the digital computer program Shuttle Attitude and Pointing Time Line Processor (SAPT) are presented. Results are typical of those utilized to provide the information required to update Baseline Reference Mission Attitude and Pointing Time Lines. Descriptions of SAPT modifications implemented to perform these analyses are also presented.

  17. Star Tracker Based ATP System Conceptual Design and Pointing Accuracy Estimation

    Science.gov (United States)

    Orfiz, Gerardo G.; Lee, Shinhak

    2006-01-01

    A star tracker based beaconless (a.k.a. non-cooperative beacon) acquisition, tracking and pointing concept for precisely pointing an optical communication beam is presented as an innovative approach to extend the range of high bandwidth (> 100 Mbps) deep space optical communication links throughout the solar system and to remove the need for a ground based high power laser as a beacon source. The basic approach for executing the ATP functions involves the use of stars as the reference sources from which the attitude knowledge is obtained and combined with high bandwidth gyroscopes for propagating the pointing knowledge to the beam pointing mechanism. Details of the conceptual design are presented including selection of an orthogonal telescope configuration and the introduction of an optical metering scheme to reduce misalignment error. Also, estimates are presented that demonstrate that aiming of the communications beam to the Earth based receive terminal can be achieved with a total system pointing accuracy of better than 850 nanoradians (3 sigma) from anywhere in the solar system.

  18. An enhanced Cramér-Rao bound weighted method for attitude accuracy improvement of a star tracker

    Science.gov (United States)

    Zhang, Jun; Wang, Jian

    2016-06-01

    This study presents a non-average weighted method for the QUEST (QUaternion ESTimator) algorithm, using the inverse value of root sum square of Cramér-Rao bound and focal length drift errors of the tracking star as weight, to enhance the pointing accuracy of a star tracker. In this technique, the stars that are brighter, or at low angular rate, or located towards the center of star field will be given a higher weight in the attitude determination process, and thus, the accuracy is readily improved. Simulations and ground test results demonstrate that, compared to the average weighted method, it can reduce the attitude uncertainty by 10%-20%, which is confirmed particularly for the sky zones with non-uniform distribution of stars. Moreover, by using the iteratively weighted center of gravity algorithm as the newly centroiding method for the QUEST algorithm, the current attitude uncertainty can be further reduced to 44% with a negligible additional computing load.

  19. An enhanced Cramér-Rao bound weighted method for attitude accuracy improvement of a star tracker.

    Science.gov (United States)

    Zhang, Jun; Wang, Jian

    2016-06-01

    This study presents a non-average weighted method for the QUEST (QUaternion ESTimator) algorithm, using the inverse value of root sum square of Cramér-Rao bound and focal length drift errors of the tracking star as weight, to enhance the pointing accuracy of a star tracker. In this technique, the stars that are brighter, or at low angular rate, or located towards the center of star field will be given a higher weight in the attitude determination process, and thus, the accuracy is readily improved. Simulations and ground test results demonstrate that, compared to the average weighted method, it can reduce the attitude uncertainty by 10%-20%, which is confirmed particularly for the sky zones with non-uniform distribution of stars. Moreover, by using the iteratively weighted center of gravity algorithm as the newly centroiding method for the QUEST algorithm, the current attitude uncertainty can be further reduced to 44% with a negligible additional computing load.

  20. Heavy Flavor Physics in Heavy-Ion Collisions with STAR Heavy Flavor Tracker

    Science.gov (United States)

    Zhang, Yifei

    2010-02-01

    Heavy quarks are a unique tool to probe the strongly interacting matter created in relativistic heavy-ion collisions at RHIC energies. Due to their large mass, energetic heavy quarks are predicted to lose less energy than light quarks by gluon radiation when they traverse a Quark-Gluon Plasma. In contrast, recent measurements of non-photonic electrons from heavy quark decays at high transverse momentum (pT) show a jet quenching level similar to that of the light hadrons. Heavy quark are produced mainly at early stage in heavy-ion collisions, thus they are proposed to probe the QCD medium and to be sensitive to bulk medium properties. Ultimately, their flow behavior may help establish whether light quarks thermalize. Therefore, topological reconstruction of D-mesons and identification of electrons from charm and bottom decays are crucial to understand the heavy flavor production and their in medium properties. The Heavy Flavor Tracker (HFT) is a micro-vertex detector utilizing active pixel sensors and silicon strip technology. The HFT will significantly extend the physics reach of the STAR experiment for precise measurement of charmed and bottom hadrons. We present a performance study with full detector on the open charm nuclear modification factor, elliptic flow v2 and λc measurement as well as the measurement of bottom mesons via a semi-leptonic decay. )

  1. Calibration of the Heavy Flavor Tracker (HFT) detector in star experiment at RHIC

    Science.gov (United States)

    Alanazi, Norah

    This project is in the area of Relativistic Nuclear collisions and the commissioning of a new silicon vertex detector, the Heavy Flavor Tracker (HFT) in the STAR experiment at Brookhaven National Laboratory (BNL). BNL hosts RHIC, the Relativistic Heavy Ion Collider, the world's most advanced dedicated heavy ion and polarized proton accelerator facility. Heavy Ion collisions at RHIC provide a unique probe into the understanding of several aspects of the behavior of nuclear, i.e. strongly inter- acting, matter. Among the many insights that can be provided is the description of parton interaction inside the hot and dense medium produced in the early stages of a collision. It also allows us to search for evidence for a phase transition in nuclear matter, a phase where partons [quarks and gluons] can move freely over an extended volume. Production of heavy quarks in high-energy nuclear collisions at RHIC occurs mainly during the initial collisions where energetic gluon and quark interactions can create heavy quarks. Thus, heavy flavor provides an ideal probe in studying the hot and dense medium created in the early phases of high-energy nuclear collisions. A detailed study of heavy flavor is essential to better understand the parton dynamics and select among competing theoretical approaches, however, precise measurements of heavy flavor are difficult to obtain due to relatively low production rates and short lifetimes of heavy flavor hadrons. The combinatorial background in nuclear collisions makes the measurement of heavy flavor a challenging task. One approach to dramatically reduce the combinatorial background by several orders of magnitude is to separate the heavy-flavor hadron's decay vertex from the background. This is done with the help of high resolution vertex detectors. The Heavy Flavor Tracker upgrade for the STAR experiment, which made its debut during the year 2014 RHIC run (Run14), greatly improved the experiment's track pointing capabilities making STAR

  2. Conceptual design and algorithm evaluation for a very accurate imaging star tracker for deep- space optical communications

    Science.gov (United States)

    Maurer, Donald E.; Boone, Bradley G.

    2002-12-01

    The National Aeronautics and Space Administration is planning high data rate optical communications for future deep space missions. The Johns Hopkins University Applied Physics Laboratory (JHU/APL) is responding by developing concepts for implementing optical communications terminals that are more compact and lightweight than heretofore. An essential requirement for these long-range optical links is a high-precision pointing and tracking system. Focal plane array (FPA)-based star trackers that enable open-loop pointing and tracking are necessary. Spacecraft attitude instabilities, emphemeris errors, tracking sensor noise, clock errors, and mechanical misalignments are among the error sources that must be minimized and compensated for. To achieve this JHU/APL has developed an imaging star tracker concept using redundant multi-aperture FPA's symmetrically disposed about the laser downlink. Centroid estimation and pattern matching techniques account for aberration and motion errors. Robustness, sensitivity to detection thresholds, field-of-view sizing, number of stars per frame, missed detections, false alarms, and position biases, as well as stellar catalog size and star selection, will be described. Finally the conceptual design of a frame-to-frame integration method and sensor fusion algorithm (such as a Kalman filter) will be considered. The goal is to achieve a system pointing and tracking error significantly less than 1 μrad.

  3. A method of autonomous orbit determination for satellite using star sensor

    Institute of Scientific and Technical Information of China (English)

    MA; Jianbo; XU; Jin

    2005-01-01

    In this paper a method of autonomous orbit determination using star sensor is studied. By building relatively consummate dynamical models which simulate attitude motion of satellite and observation from satellite to background stars, the simulant computation of this method is executed, and it is shown that the method of autonomous orbit determination is feasible. Academic and calculation analyses have been done for the relation between the direction of star sensor with respect to satellite-body coordinate system and the accuracy of autonomous orbit determination.

  4. Development of star tracker system for accurate estimation of spacecraft attitude

    OpenAIRE

    Tappe, Jack A.

    2009-01-01

    Approved for public release, distribution unlimited This thesis researches different star pattern recognition and attitude determination algorithms for a three-axis rotational spacecraft. A simulated star field will be suspended above the experimental Three-Axis Spacecraft simulator to proved a reference for the star-pattern recognition algorithms. A star field inertial reference frame database of stars will be developed with the simulator at zero attitude. The angle, planar triangle an...

  5. 船用星敏感器星图模拟方法%A Star Image Simulation Method for a Marine Star Tracker

    Institute of Scientific and Technical Information of China (English)

    李辉; 王安国; 张磊; 佟帅

    2013-01-01

    A high-precision real-time star image simulation method is proposed for the emulational test of a marine star tracker. The computation model for star image simulation is established, and the non-stellar elements simulation method is analyzed. The related algorithms are realized by Visual C++programming. Typical star image simulation examples are presented and compared with the star images generated by Starry Night. The results show that this proposed method can be used to achieve star image simulation for a marine star tracker under various operating conditions. The elements of simulation are complete and correct. The simulation accuracy is comparable to the accuracy of Starry Night at sub-pixel level. And the simulation time for each image is about 24.8 ms. This method meets well the basic requirements of high-precision real-time emulational test of a marine star tracker.%  针对船用星敏感器的仿真测试,提出一种高精度实时星图模拟方法.建立了星图模拟计算模型,并对非恒星要素的模拟方法进行分析.采用Visual C++编程实现相关算法.给出典型星图模拟实例,并与Starry Night软件产生的星图进行比对.结果表明,本文提出的方法能够对船用星敏感器各种运行场景下的星图进行模拟,模拟要素完整、正确,模拟精度与Starry Night接近至亚像素级别,每帧模拟星图生成时间约24.8 ms.能够满足船用星敏感器高精度实时仿真测试要求.

  6. The Bering Autonomous Target Detection

    DEFF Research Database (Denmark)

    Jørgensen, John Leif; Denver, Troelz; Betto, Maurizio;

    2003-01-01

    autonomous star tracker the Advanced Stellar Compass (ASC). One feature of this instrument is that potential targets are registered directly in terms of date, right ascension, declination, and intensity, which greatly facilitates both tracking search and registering. Results from ground and inflight tests...... are encouraging, both with respect to robustness, speed and accuracy, and demonstrates the span and range of applications of this technology....

  7. An enhanced Cramér-Rao bound weighted method for attitude accuracy improvement of a star tracker.

    Science.gov (United States)

    Zhang, Jun; Wang, Jian

    2016-06-01

    This study presents a non-average weighted method for the QUEST (QUaternion ESTimator) algorithm, using the inverse value of root sum square of Cramér-Rao bound and focal length drift errors of the tracking star as weight, to enhance the pointing accuracy of a star tracker. In this technique, the stars that are brighter, or at low angular rate, or located towards the center of star field will be given a higher weight in the attitude determination process, and thus, the accuracy is readily improved. Simulations and ground test results demonstrate that, compared to the average weighted method, it can reduce the attitude uncertainty by 10%-20%, which is confirmed particularly for the sky zones with non-uniform distribution of stars. Moreover, by using the iteratively weighted center of gravity algorithm as the newly centroiding method for the QUEST algorithm, the current attitude uncertainty can be further reduced to 44% with a negligible additional computing load. PMID:27370431

  8. In-flight calibration and performance evaluation of the fixed head star trackers for the solar maximum mission

    Science.gov (United States)

    Thompson, R. H.; Gambardella, P. J.

    1980-01-01

    The Solar Maximum Mission (SMM) spacecraft provides an excellent opportunity for evaluating attitude determination accuracies achievable with tracking instruments such as fixed head star trackers (FHSTs). As a part of its payload, SMM carries a highly accurate fine pointing Sun sensor (FPSS). The EPSS provides an independent check of the pitch and yaw parameters computed from observations of stars in the FHST field of view. A method to determine the alignment of the FHSTs relative to the FPSS using spacecraft data is applied. Two methods that were used to determine distortions in the 8 degree by 8 degree field of view of the FHSTs using spacecraft data are also presented. The attitude determination accuracy performance of the in flight calibrated FHSTs is evaluated.

  9. Contingency Operations during Failure of Inertial Attitude Acquisition Due to Star Tracker Blinding for Three-Axes-Stabilized Interplanetary Spacecraft

    Science.gov (United States)

    Keil, Joachim; Herfort, Ulrich

    2007-01-01

    The three interplanetary ESA missions Mars-Express, Rosetta and Venus-Express (launched 2003, 2004 and 2005 resp.) are three-axes stabilized spacecraft (s/c) that estimate their inertial attitude (i.e. the attitude of the s/c w.r.t. the inertial frame) using measurements from a redundant set of star trackers (STR). Each s/c is equipped with four reaction wheels, a reaction control system based on thrusters and a redundant set of ring laser gyroscopes (gyros). The STR h/w layout of the three s/c is identical whereas there is a difference in the star pattern recognition algorithm of Rosetta which uses five neighbouring stars around a central star instead of star triads. The Rosetta algorithm has been implemented to cope with the presence of false stars which are expected to be seen during operations around the comet. The attitude acquisition capability from lost in space is different also in terms of AOCMS: The survival mode of Rosetta which is entered upon STR failure is presented. The AOCMS of Mars- and Venus-Express manages temporary STR outages during sky occultation by the planet not even by using redundancy. Though, a blinding of both STR during cruise lasting for the order of days confronts the ground operators with the limits of the AOCMS design. The operations and analyses that have been planned and partially been performed to compensate for the outage of the STR are demonstrated for Mars-Express. The caution measures taken before Venus orbit insertion of Venus-Express are detailed.

  10. FLAT: Folded Low-profile Autonomous star Tracker for cubesats/smallsats Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Perform trade studies over folded aperture optics to specify design parameters - diameter, effective aperture, sensitivity, field of view; Model, design, fabricate...

  11. Autonomous satellite constellation orbit determination using the star sensor and inter-satellite links data

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A method of autonomous orbit determination for a satellite constellation using a star sensor combined with inter satellite links(ISLs) is studied.Two types of simulated observation data,Three-Satellite Constellation ISLs and background stellar observations by a CCD star sensor,are first produced.Based on these data,an observation equation is built for the constellation joint autonomous orbit determination,in which the simulations are run.The accuracy of this method with different orbital determination models are analyzed and compared with regard to the effect of potential measurement errors.The results show that autonomous satellite constellation orbit determination using star sensor measurement and ISLs data is feasible.Finally,this paper arrives at several conclusions which contribute to extending this method to a more general satellite constellation.

  12. Optical System Error Analysis of High Accuracy Star Trackers%高精度星敏感器光学系统误差分析

    Institute of Scientific and Technical Information of China (English)

    孙婷; 邢飞; 尤政

    2013-01-01

    在对影响星敏感器精度的误差源做出权重分析和比较的基础上,提出一种基于蒙特卡罗模拟的星敏感器精度误差分析方法,避免冗长和繁琐的理论推导,直观且系统地分析了星敏感器误差传播关系,建立星敏感器误差传播模型,为星敏感器的优化设计、标定补偿提供依据和准则,通过仿真验证误差传播模型及误差分析方法的准确性,为高精度星敏感器的设计制造提供重要基础和保证.%A synthetic error analysis approach is proposed in detail based on error source weight analysis and comparison of the star tracker using Monte Carlo method. It can avoid long and cumbersome theoretical derivation, which can provide error propagation relation of the star tracker intuitively and systematacially. The error propagation model can provide foundation and rule for optimization design, calibration and compensation of the star tracker. Simulation consequences prove that the systematic analysis is adequate and precise, which can provides important guarantee for design and manufacture of high accuracy star trackers.

  13. The measurement of hadronic observables with the solenoidal tracker at RHIC (STAR)

    Energy Technology Data Exchange (ETDEWEB)

    Bellwied, R. [Wayne State Univ., Detroit, MI (United States)

    1995-07-15

    The authors describe the capabilities of the STAR detector at RHIC regarding the measurement of hadronic observables. Special emphasis will be given to the determination of event-by-event observables deduced from particle spectra for protons (p), kaons (K) and pions ({pi}). The authors show that based on the present status of the simulations STAR will be able to measure quantities such as , slope parameter, and particle ratios on an event-by-event basis. These parameters, in connection with charged particle multiplicities as a function of momentum and rapidity, may shed light on the occurance of a phase transition in ultrarelativistic heavy ion collisions.

  14. Heavy Flavor Tracker (HFT) : A new inner tracking device at STAR

    OpenAIRE

    Bouchet, Jonathan; Collaboration, for the STAR

    2009-01-01

    The HFT, a new inner tracking detector for STAR, aims to measure the charmed hadron nuclear modification factor as well as their elliptic flow to the low $p_\\mathrm{T}$ region ($\\sim$0.5 GeV/c) by measuring the displaced vertices of charmed particles.

  15. Heavy Flavor Tracker (HFT) : A new inner tracking device at STAR

    CERN Document Server

    2009-01-01

    The HFT, a new inner tracking detector for STAR, aims to measure the charmed meson nuclear modification factor as well as their elliptic flow in low $p_\\mathrm{T}$ region (0.5 - 2 GeV/c) by measuring the displaced vertices of charmed particles.

  16. In-flight scale/distortion calibration of the Hubble Space Telescope fixed-head star trackers

    Science.gov (United States)

    Mccutcheon, R.; Boia, John J.; Gakenheimer, Martin F.; Hallock, L.; Kimmer, E.; Murphy, S.; Welter, Gary L.

    1994-01-01

    This paper describes an in-flight scale and distortion calibration procedure that has been developed for the Ball Aerospace Systems Division Fixed-Head Star Trackers (FHST's) used on the Hubble Space Telescope (HST). The FHST is a magnetically focused and deflected imaging sensor that is designed to track stars as faint as m(sub v) = 5.7 over an 8 degree by 8 degree field of view. Raw FHST position measurements are accurate to approximately 200 arcseconds, but this can be improved to 10-15 arcseconds by processing the raw measurements through calibration polynomials that correct for flat field, temperature intensity, and magnetic field effects. The coefficients for these polynomials were initially determined using ground test data. On HST the use of three FHST's is an integral part of the preliminary attitude update procedures required before the acquisition of guide stars for science observations. To this end, FHST-based attitude determination having single-axis errors no worse than 22 arcseconds (1 sigma) is required. In early 1991 it became evident that one of the HST FHST's was experiencing a significant change in its optical scale. By mid-1993 the size of this error had grown to a point that, if not corrected, it would correspond to a maximum position error on the order of 100 arcseconds. Subsequent investigations demonstrated that substantial, uncompensated cubic distortion effects had also developed, the maximum contribution to position errors from the cubic terms being on the order of 30 arcseconds. To ensure accurate FHST-based attitude updates, procedures have been developed to redetermine the FHST scale and distortion calibration coefficients based on in-flight data gathered during normal HST operations. These scale and distortion calibrations have proven very effective operationally, and procedures are in place to monitor FHST calibration changes on a continuing basis.

  17. Experience from the in-flight calibration of the Extreme Ultraviolet Explorer (EUVE) and Upper Atmosphere Research Satellite (UARS) fixed head star trackers (FHSTs)

    Science.gov (United States)

    Lee, Michael

    1995-01-01

    Since the original post-launch calibration of the FHSTs (Fixed Head Star Trackers) on EUVE (Extreme Ultraviolet Explorer) and UARS (Upper Atmosphere Research Satellite), the Flight Dynamics task has continued to analyze the FHST performance. The algorithm used for inflight alignment of spacecraft sensors is described and the equations for the errors in the relative alignment for the simple 2 star tracker case are shown. Simulated data and real data are used to compute the covariance of the relative alignment errors. Several methods for correcting the alignment are compared and results analyzed. The specific problems seen on orbit with UARS and EUVE are then discussed. UARS has experienced anomalous tracker performance on an FHST resulting in continuous variation in apparent tracker alignment. On EUVE, the FHST residuals from the attitude determination algorithm showed a dependence on the direction of roll during survey mode. This dependence is traced back to time tagging errors and the original post launch alignment is found to be in error due to the impact of the time tagging errors on the alignment algorithm. The methods used by the FDF (Flight Dynamics Facility) to correct for these problems is described.

  18. Hubble Space Telescope Star Tracker ad Two-Gyro Control Law Design, Implementation, and On-Orbit Performance. Part 2

    Science.gov (United States)

    VanArsdall, John C.

    2005-01-01

    The Hubble Space Telescope (HST) normally requires three gyroscopes for three-axis rate control. The loss of the Space Shuttle Columbia on STS-107 resulted in the cancellation of a shuttle-based HST Servicing Mission 4. Therefore, HST must operate using the on-board hardware until an alternate means of servicing can be accomplished. The probability of gyro failure indicates that fewer than three gyros will be operable before any servicing mission can be performe& To mitigate this, and to extend the HST life expectancy, a rate estimation and control algorithm was developed that requires two gyros to measure rate about two axes, with the remaining axis rate estimated using one of three alternate sensors. Three-axis magnetometers (MSS) are used for coarse rate estimation during large maneuvers and during occultations of other sensors. Fixed-Head Star Trackers (FHSTs) are used for rate estimation during safe mode recovery and during transition to science operations. Fine rate estimation during science operations is performed using the Fine Guidance Sensors (FGSs). The FHST mode (T2G) relies on star vectors as measured by the FHSTs to estimate vehicle rate about the axis not measured by the gyros. Since the FHSTs were not designed to estimate body rate, this method involves a unique set of problems that had to be overcome in the final design, such as the effect of FHST break tracks and moving targets on rate estimation. The solutions to these problems, as well as a detailed description of the design and implementation of the rate estimation are presented Also included are the time domain and frequency domain analysis of the T2G control law. A high fidelity HST simulator (HSTSIM) was used to verify T2G performance prior to on-orbit use. Results of these simulations are also presented. Finally, analysis of actual T2G on-orbit test results is presented for design validation.

  19. A computer-aided telescope pointing system utilizing a video star tracker

    Science.gov (United States)

    Lorell, K. R.; Murphy, J. P.; Swift, C. D.

    1976-01-01

    The Video Inertial Pointing (VIP) System is being developed to satisfy the acquisition and pointing requirements of astronomical telescopes. VIP employs a single video sensor to generate three-axis pointing error signals and to provide inputs for a cathode ray tube (CRT) display of the star field. The pointing error signals update the telescope's gyro stabilization system. The CRT display facilitates target acquisition and positioning of the telescope by a remote operator. The present paper describes the analysis, simulation, and hardware development of a prototype, advanced VIP system. An early model of the system utilizing a silicon-intensified target vidicon camera has flown on a balloon-borne telescope and is briefly described. The advanced system, which can employ either a vidicon camera or a charge-coupled device video sensor, has been tested using an analog/digital hybrid simulation. The advanced VIP hardware is described, and the simulation results presented.

  20. 捷联惯性/大视场星光组合导航方法研究%The Research on Integrated Navigation Method of SINS/Star with Large View Field Star Tracker

    Institute of Scientific and Technical Information of China (English)

    李双喜; 张宗梅; 张俊

    2011-01-01

    Recently, the integrated navigation using star tracker in missiles and rockets becomes a hotspot in both domestic and oversea. The integrated navigation method of SINS/Star with large view field star tracker is studied and the Kalman filter equation is established in this paper. Using the SINS error transfer matrix method, the navigation error of ballistic missile in ascend phase is also estimated. The simulation resubs show that the integrated navigation method of SINS/Star with large view field star tracker can revise attitude angle error and gyroscope constant drift while the velocity and position error in ascend phase can also be estimated.%近年来,使用星敏感器的导弹、火箭惯性组合导航成为国内外研究的热点.本文对捷联惯性/大视场星光组合导航方法进行了研究,建立了卡尔曼滤波方程,并利用SINS误差转移矩阵方法估计主动段导航误差.数学仿真表明:捷联惯性/大视场星光组合导航方法不仅可以修正姿态角偏差和陀螺常值漂移,还可以对主动段的速度、位置误差有很好的估计效果.

  1. Thermo-optic Effects on Accuracy Performance of Star Tracker%热-光效应对星敏感器测量准确度的影响

    Institute of Scientific and Technical Information of China (English)

    刘海波; 黄水花; 谭吉春; 贾辉; 杨建坤; 杨俊才

    2009-01-01

    Thermo-optic effects on position accuracy of star tracker was analysised using opto-mechanical coupling method.The displacements of star centroids and sub-pixel interpolation errors,caused by three kinds of temperature distribution respectively,were calculated quantitatively in a typical optical system of star tracker.The measurement error of star tracker was about 0.07″,when uniform temperature changed 20℃.The measurement errors were about 0.17″and 0.31″,respectively,when temperature difference were 10℃ and 20℃ in axis.And it was as much as 1.46″,when temperature distribution difference between top of the optical system and the bottom was only 2℃.The results show that temperature distribution difference between the top and the bottom has serious effects on measurement accuracy of star tracker,and uniform temperature distribution has a little.%运用"热-结构-光"耦合分析方法,计算典型星敏感器光学系统(6透镜光具组,f=56 mm,相对孔径1/1.3)恒星像斑理想质心位移和亚像元内插质心偏移量,研究温度分布对星敏感器测量准确度的影响.以20℃为光学系统标定温度,计算光学系统均匀温度分布、轴向温差分布和上下侧温差分布三种条件下,星敏感器测量误差.均匀分布温度变化20℃时,星敏感器测量误差约0.07″;轴向温差10℃和20℃时,测量误差分别约为0.17″和0.31″;上下侧温差仅2℃时,测量误差就高达1.46″.计算结果表明,上下侧温差分布对星敏感器准确度影响最大,均匀温度分布影响最小.

  2. Optimized Design of Optical Lens of Star Tracker%星跟踪器光学系统的优化设计

    Institute of Scientific and Technical Information of China (English)

    王立秋; 田明; 崔士宝

    2015-01-01

    在星光制导的空间飞行器中,为准确确定空间方位信息,提高导航系统的精度,对星跟踪器光学镜头设计提出很高的要求。针对精度要求,设计了一种新型星跟踪器的光学镜头,系统地阐述了星跟踪器的工作原理,通过光学设计及相差分析,使光学系统的畸变小于0.2%、轴向球差小于0.1,该设计满足用户对高精度天文导航系统的需求。%In the star light guidance of space vehicles, the optical lens design requirements for star tracker are critical to determine accurately the spatial location information and to improve the accuracy of navigation system. A new type of star tracker optical lens system is designed according to the requirements and the operation principle is presented. With the optical design and difference analysis, the optical system distortion is less than 0.2%, the axial spherical aberration is less than 0.1, which can meet the demand for high-precision astronomical navigation system.

  3. STARS: A software application for the EBEX autonomous daytime star cameras

    CERN Document Server

    Chapman, Daniel; Hanany, Shaul; Hillbrand, Seth; Limon, Michele; Miller, Amber; Reichborn-Kjennerud, Britt; Tucker, Greg; Vinokurov, Yury

    2014-01-01

    The E and B Experiment (EBEX) is a balloon-borne telescope designed to probe polarization signals in the CMB resulting from primordial gravitational waves, gravitational lensing, and Galactic dust emission. EBEX completed an 11 day flight over Antarctica in January 2013 and data analysis is underway. EBEX employs two star cameras to achieve its real-time and post-flight pointing requirements. We wrote a software application called STARS to operate, command, and collect data from each of the star cameras, and to interface them with the main flight computer. We paid special attention to make the software robust against potential in-flight failures. We report on the implementation, testing, and successful in flight performance of STARS.

  4. 适用于小视场星敏感器的导航星表构建方法%Guide star selection method for star tracker with thin field of view

    Institute of Scientific and Technical Information of China (English)

    崔祥祥; 王宏力; 陆敬辉; 乔兴; 邓长智; 张勇; 赵爱罡

    2015-01-01

    Guide star selection is a crucial part of star tracker design. For thin field-of-view star tracker, guide star catalog "holes" are common as stars are not evenly distributed. To optimize the guide star selection for star tracker with thin field of view, the selection method based on spherical spiral points was modified. Building a new guide star catalog by increasing the number and changing the positions of spherical spiral points, which was usually adopted, was abandoned. Some new stars which can effectively decrease guide star catalog "holes" into the guide star catalog were proposed. The weights to measure stars’ ability of decreasing guide star catalog "holes" were constructed and the adding star process was carried out on the order of the weights descending. And the new star added into guide star catalog was required far away from the guide stars to keep the guide stars even. Simulations expressed that the modified method got less and evener guide stars than the original method with similar guide star catalog"holes", which shows the superiority of the modified method.%导航星表构建是星敏感器设计阶段的重要工作。对于小视场,受限于恒星分布规律,易出现导航星表“空洞”问题。为解决小视场条件下均匀完备导航星表构建问题,对基于球面螺旋基准点的导航星表构建方法进行了改进:摒弃了原方法通过改变球面螺旋基准点数量和位置重新构建导航星表的思路,转而通过增选部分恒星来达到减少星表“空洞”的目的。设立了描述恒星消除星表“空洞”能力的权值,并以该权值递减顺序开展恒星增选;同时,设计了增选恒星距离阈值条件以保持增选后导航星表的均匀性。仿真表明,在4º圆形视场条件下,相对于原方法,文中方法得到的导航星表,总星数减少708颗,均匀性指标提高约44%,而星表“空洞”变化较小,显示了较好的性能。

  5. Analysis of influence of earth albedo on star tracker%地球反照对星敏感器的影响分析

    Institute of Scientific and Technical Information of China (English)

    张春明; 解永春; 王立; 赵春晖; 钟红军

    2012-01-01

    A geometry optical model for analyzing the influence of earth albedo on star tracker is presented. Based on the principle of photometry and Point Source Transmittance(PST) ,this model has a certain generality and practicability by means of dividing earth surfaces into 2D cells with longitude and attitude and providing application interface of available TOMS reflectance data. It can be used to analyze the magnitude of irradiance of entrance and exit of a sunshade and corresponding imaging surface at different off-axis angles,where earth albedo pours on within some conditions, including altitude of orbit,installing position of star tracker,incident angle of sun,etc. Based on this model,we can make proposal of installing orientation of star tracker on satellites and estimate anti-earth albedo performance of sunshade of star tracker. Simulation indicates that for MEO and LEO, the irradiance of earth albedo reaching the entrance of sunshade of star tracker changes little, the magnitude of irradiance of earth albedo received by the exit of sunshade is mainly related to its PST and installation elevation; When this angle is equal to 32. 5°,the irradiance of the exit of sunshade declines to 10 -7 W/m2 ,thus satisfying sunshade's requirement of suppressing stray light.%利用光度学的概念和点源辐射传输率(PST),提出了一种分析地球反照对星敏感器的影响的几何光学模型.该模型对地球表面按照经纬度划分了网格,为已知的TOMS反射数据的应用提供了接口,具有一定的通用性和实用性,可简要分析卫星上的星敏感器在一定输入条件下,包括轨道高度、星敏感器的安装方位、太阳入射角度等,地球反照到达遮光罩入口、出口的照度,以及不同离轴角下像面接收的地球反照的照度值.借助此模型,可以为星敏感器在卫星上的安装方位提出建议,并估算出星敏感器遮光罩的抗地球反照干扰性能.仿真分析表明,对于中低轨道而言,

  6. 一种新的方法用于星敏感器近红外星图星点提取%A new method used for star distillation of near-infrared star image of star tracker

    Institute of Scientific and Technical Information of China (English)

    廖育富; 钟建勇

    2014-01-01

    分析了近红外星图小波分解系数的特点。依据小波分析的边缘检测特性、解相关性和多分辨率特性结合星点的灰度分布特征设计了不同尺度下的检测模板。在恒虚警概率条件下,提出利用局部阈值克服红外星图本身的背景不均匀性。通过在星图第二次分解的近似系数上检测星点最大灰度值的位置,削弱了单点噪声和条纹噪声的影响。实验结果显示,算法能有效得出视场中的星点最大灰度值坐标,误差在1个像素位置左右,满足后续星点提取的需要。%The distillation of near-infrared star image of star tracker was analyzed in this paper. A new method for this problem was presented. Firstly, characters of near-infrared star image in wavelet domain were analyzed and mask used to detect stars in multi scales were designed according to the distribution of the gray of stars. Then, local threshold was applied to overcome the imbalance of the background under the constant false alarm rate. Lastly, positions of the heaviest gray values of stars in the secondly decomposed approximation coefficients were accessed, eliminating the effect of the single point noise and stripe noise. Experimental results indicate that the method could efficiently obtain the position of the heaviest gray value of detected stars with error around one pixel, which satisfies the requirement of estimation of centroid.

  7. Modeling and accuracy analysis for multiple heads star tracker%多视场星敏感器数学模型与精度分析

    Institute of Scientific and Technical Information of China (English)

    李健; 张广军; 魏新国

    2015-01-01

    多视场星敏感器与传统单视场星敏感器相比不仅具有更高的可靠性和自主性,也具有更高的精度和动态性能,是未来星敏感器发展的重要趋势之一。为获得最佳性能,需要对多视场星敏感器的视场大小和布局进行优化。为此,首先建立了多视场星敏感器的数学模型,重点介绍了星点成像和姿态计算。然后推导了多视场星敏感器测量精度的数学表示,分析了影响精度的因素。通过仿真分析了多视场星敏感器视场大小和布局对各因素和精度的影响。仿真结果表明,视场大小对星敏感器精度的影响取决于星敏感器的运动情况,当角速度较小时,视场越小,精度越高;当角速度较大时,视场越大,精度越高。而各视轴相互正交的视场布局下,多视场星敏感器的测量精度最高。%As an important trend in the future, multiple heads star tracker is not only of higher reliability and autonomy, but also of higher precision and dynamic performance than classical star tracker. In order to achieve the best performance, system parameters optimization for multiple heads star tracker is needed. A mathematical model of multiple heads star tracker was developed firstly, particularly on the star imaging and attitude determination. Then an analytic expression of accuracy was deduced, and the error sources affecting the attitude accuracy were analyzed. Finally, the effects of the field of view and the relative alignment on the accuracy were discussed systematically based on the simulation results. The results show that the relation between field of view and accuracy depends on the angular rate. The accuracy is improved with smaller field of view at lower angular rate, while with larger field of view at higher angular rate. And multiple heads star sensor reaches the highest precision when the boresights are orthogonal.

  8. GLAST Tracker

    CERN Document Server

    Tajima, H

    2006-01-01

    The Large Area Telescope (LAT) on board the Gamma-ray Large-Area Space Telescope (GLAST) is a pair-conversion gamma-ray detector designed to explore the gamma-ray universe in the 20 MeV-300 GeV energy band. The Tracker subsystem of the LAT will perform tracking of electron and positrons to determine the origin of the gamma-ray. The design and performance of the GLAST LAT Tracker are described in this paper.

  9. INNER TRACKER

    CERN Multimedia

    Karl Gill

    A series of important milestones have been passed during the last 3 months. With the delivery of refurbished cooling systems, pixels and strip systems have been brought back into operation after long shutdowns. Pixels has been operating since reinsertion of FPIX in April, and has been running at 4°C since May 16 when the bulkhead thermal screen was commissioned. More recently, on June 10 the Strip Tracker was powered up in its entirety, with cooling fluid circulating at 4°C, allowing commissioning of the Strip Tracker to proceed at full speed. The full Tracker is well on course to be ready for CRAFT, with Strip Tracker readout operation in ‘peak’ mode remaining also on track to be ready for beam operations in the Autumn in ‘deconvolution’ readout mode. The main Tracker activity during the shutdown was the cooling plant refurbishment for Strips and Pixels systems. The objectives were to reduce the serious leaks observed in 2008 and improve the longevity...

  10. INNER TRACKER

    CERN Document Server

    P. Sharp

    The CMS Inner Tracking Detector continues to make good progress. The Objective for 2007 is to deliver to CMS a completed, installed, commissioned and calibrated Tracking System (Silicon Strip and Pixels) aligned to < 100µ in April 2008 ready for the first physics collisions at LHC. On 21 March 2007, the integration of the CMS Silicon Strip Tracker was completed with the successful integration of TEC- into the Tracker Support Tube (TST). Since then ~25% of the complete Tracker Systems has been commission at the TIF at both room temperature and operating temperature (-100 C), and the Tracker Community has gained very valuable experience in operating, calibrating and aligning the Tracker at the TIF before it is prepared for transportation to P5 in July 2007. The CMS Pixel System continues to make good progress. Module and Plaquette production is very well advanced. The first 25% of the Forward Pixel detector (Fpix) was delivered to CERN in April and the second 25% will shipped to CERN on 19 ...

  11. INNER TRACKER

    CERN Document Server

    K. Gill.

    The clear highlight of recent months was switching on the Tracker to capture the first LHC collisions with 450GeV beams. This was during the first trial run of the LHC on 23rd November. On that day, the Tracker Outer Barrel (TOB) was powered and the detector performance was excellent, in accord with our expectations. Since then, the full Tracker, strips and pixels, has been powered up during “quiet” beam periods when there was judged to be little risk of damage due to sudden beam losses. All Tracker systems performed very well, considering the beam and trigger conditions in place, and we now eagerly anticipate the first collisions with stable beams. Besides this very intense and exciting recent period there has been a lot of other activity in the last 6 months. The full Tracker participated in CRAFT09 and operations of all systems went very smoothly for both pixels and strips, validating all the meticulous work that had taking place during the long shutdown, the subsequent re-commissionin...

  12. INNER TRACKER

    CERN Multimedia

    K. Gill

    During the winter shutdown several parts of the Tracker system are undergoing maintenance, revision or upgrade. The main items are the revision of the strips and pixels cooling plants, removal and maintenance of FPIX, sealing of Tracker patch-panels and the bulkhead, integration of strips and pixels DCS, and further development of the DAQ, Online and commissioning software and firmware. The revision of the cooling system involves the complete replacement of the tanks, distribution lines, valves and manifolds on the SS1 and SS2 strip tracker (182 circuits) and pixels (36 circuits) cooling plants. The objectives are to eliminate the large leaks experienced during 2008 operations and to assure the long-term reliability of the cooling systems. Additional instrumentation is being added to provide more detailed monitoring of the performance of the cooling system. This work is proceeding smoothly under close supervision. Procurements are almost completed and the quality of delivered parts and the subsequent assembl...

  13. Results from a Prototype MAPS Sensor Telescope and Readout System with Zero Suppression for the Heavy Flavor Tracker at STAR

    OpenAIRE

    Greiner, Leo C.; Matis, Howard S.; Ritter, Hans G.; Rose, Andrew A.; Stezelberger, Thorsten; Sun, Xiangming; Szelezniak, Michal A.; Thomas, James H.; Vu, Chinh Q.; Wieman, Howard H.

    2008-01-01

    We describe a three Mimostar-2 Monolithic Active Pixel Sensor (MAPS) sensor telescope prototype with an accompanying readout system incorporating on-the-fly data sparsification. The system has been characterized and we report on the measured performance of the sensor telescope and readout system in beam tests conducted both at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory (LBNL) and in the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). This effo...

  14. INNER TRACKER

    CERN Multimedia

    Peter Sharp

    In March the Silicon Strip Detector had been successfully connected to the PP1 patch panels on the CMS Cryostat, and every thing had been prepared to check out the Tracker and commission it with CMS with the ambition of joining the CMS Global Cosmic Run in April.  There followed serious problems with the cooling plant which through tremendous effort have been overcome and recently allowed commissioning of the tracker to proceed. In November 2007 there had been a failure of the heat exchanger in one of the seven cooling plants in the UXC cavern. After an analysis of the failure it was decided to replace this heat exchanger with a well-proven commercial heat exchanger and to re-commission the system. Re-commissioning the system proved to be more difficult than anticipated as on May 8 there was a second failure of a heat exchanger, in the main chiller plant in the USC service cavern. The analysis of the failure showed it was very similar to the previous failure. It was decided to replace all the heat ...

  15. 一种基于天体运动学的星敏感器精度测量方法%Accuracy measurement of star trackers based on astronomy

    Institute of Scientific and Technical Information of China (English)

    孙婷; 邢飞; 尤政

    2012-01-01

    Star trackers the highest accuracy attitude measurement devices used in spacecraft. The star tracker's accuracy is especially important. A method was given to measure the accuracy of a star tracker based on astronomical principles using the earth's rotation. The star tracker's position is fixed to the earth while taking photographs of stars. The celestial coordinates in the star catalogue stored in the star tracker are transformed from the J2000.0 coordinate system to an earth fixed coordinate system taking into account axial precession, nutation, proper motion and the earth's rotation. Pointing and roll accuracy curves are acquired after the star extraction, star map recognition and attitude solution. This method conveniently, efficiently and accurately measures the star tracker's accuracy while avoiding traditional complex operations. Tests using a precise star simulator and a three-axis table verify the system's accuracy.%星敏感器是目前应用在航天飞行器中精度最高的姿态测量器件,因此其精度的标定显得尤为重要。该文提出了一种基于天体运动学规律的星敏感器精度测量方法,利用地球自转的精密性,将星敏感器与地球固连,对天顶邻域拍摄星图。同时将存储在星敏感器内的导航星表由J2000.0坐标系在考虑恒星自行、岁差、章动及地球自转影响后变换到地固坐标系,经过星点提取、星图识别和姿态解算,得到星敏感器俯仰、偏航和滚转三轴在地固坐标系中的变化,根据统计规律得出星敏感器的指向精度和滚转精度。该测量方法方便易实施,可以避免传统测试方法操作复杂、需要精密转台和星模拟器的困扰,测量精度满足星敏感器要求,具有准确性和真实性。

  16. The electromagnetic calorimeter for the solenoidal tracker at RHIC

    International Nuclear Information System (INIS)

    This report discusses the following on the electromagnetic calorimeter for the solenoidal tracker at RHIC: conceptual design; the physics of electromagnetic calorimetry in STAR; trigger capability; integration into STAR; and cost, schedule, manpower, and funding

  17. Brightness Independent 4-Star Matching Algorithm for Lost-in-Space 3-Axis Attitude Acquisition

    Institute of Scientific and Technical Information of China (English)

    DONG Ying; XING Fei; YOU Zheng

    2006-01-01

    A star identification algorithm was developed for a charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) autonomous star tracker to acquire 3-axis attitude information for a lost-in-space spacecraft. The algorithm took advantage of an efficient on-board database and an original "4-star matching" pattern recognition strategy to achieve fast and reliable star identification. The on-board database was composed of a brightness independent guide star catalog (mission catalog) and a K-vector star pair catalog. The star pattern recognition method involved direct location of star pair candidates and a simple array matching procedure. Tests of the algorithm with a CMOS active pixel sensor (APS) star tracker result in a 99.9% success rate for star identification for lost-in-space 3-axis attitude acquisition when the angular measurement accuracy of the star tracker is at least 0.01°. The brightness independent algorithm requires relatively higher measurement accuracy of the star apparent positions that can be easily achieved by CCD or CMOS sensors along with subpixel centroiding techniques.

  18. Interacting Multiview Tracker.

    Science.gov (United States)

    Yoon, Ju Hong; Yang, Ming-Hsuan; Yoon, Kuk-Jin

    2016-05-01

    A robust algorithm is proposed for tracking a target object in dynamic conditions including motion blurs, illumination changes, pose variations, and occlusions. To cope with these challenging factors, multiple trackers based on different feature representations are integrated within a probabilistic framework. Each view of the proposed multiview (multi-channel) feature learning algorithm is concerned with one particular feature representation of a target object from which a tracker is developed with different levels of reliability. With the multiple trackers, the proposed algorithm exploits tracker interaction and selection for robust tracking performance. In the tracker interaction, a transition probability matrix is used to estimate dependencies between trackers. Multiple trackers communicate with each other by sharing information of sample distributions. The tracker selection process determines the most reliable tracker with the highest probability. To account for object appearance changes, the transition probability matrix and tracker probability are updated in a recursive Bayesian framework by reflecting the tracker reliability measured by a robust tracker likelihood function that learns to account for both transient and stable appearance changes. Experimental results on benchmark datasets demonstrate that the proposed interacting multiview algorithm performs robustly and favorably against state-of-the-art methods in terms of several quantitative metrics. PMID:26336117

  19. D^0 measurements in Au+Au Collisions at \\sqrt{s_{NN}} = 200 GeV using the STAR Silicon Inner Tracker

    CERN Document Server

    2009-01-01

    We present preliminary results from D^0 meson measurements through the hadronic decay channel in minimum bias Au+Au collisions at \\sqrt{s_{NN}} = 200 GeV at STAR. The measurements are performed using a secondary vertexing technique that exploits the resolution given by the Silicon detectors available in STAR.

  20. ATLAS Transitional Radiation Tracker

    CERN Multimedia

    ATLAS Outreach

    2006-01-01

    This colorful 3D animation is an excerpt from the film "ATLAS-Episode II, The Particles Strike Back." Shot with a bug's eye view of the inside of the detector. The viewer is taken on a tour of the inner workings of the transitional radiation tracker within the ATLAS detector. Subjects covered include what the tracker is used to measure, its structure, what happens when particles pass through the tracker, how it distinguishes between different types of particles within it.

  1. STAR: The Secure Transportable Autonomous Reactor System - Encapsulated Fission Heat Source

    Energy Technology Data Exchange (ETDEWEB)

    Ehud Greenspan

    2003-10-31

    OAK-B135 The Encapsulated Nuclear Heat Source (ENHS) is a novel 125 MWth fast spectrum reactor concept that was selected by the 1999 DOE NERI program as a candidate ''Generation-IV'' reactor. It uses Pb-Bi or other liquid-metal coolant and is intended to be factory manufactured in large numbers to be economically competitive. It is anticipated to be most useful to developing countries. The US team studying the feasibility of the ENHS reactor concept consisted of the University of California, Berkeley, Argonne National Laboratory (ANL), Lawrence Livermore National Laboratory (LLNL) and Westinghouse. Collaborating with the US team were three Korean organizations: Korean Atomic Energy Research Institute (KAERI), Korean Advanced Institute for Science and Technology (KAIST) and the University of Seoul, as well as the Central Research Institute of the Electrical Power Industry (CRIEPI) of Japan. Unique features of the ENHS include at least 20 years of operation without refueling; no fuel handling in the host country; no pumps and valves; excess reactivity does not exceed 1$; fully passive removal of the decay heat; very small probability of core damaging accidents; autonomous operation and capability of load-following over a wide range; very long plant life. In addition it offers a close match between demand and supply, large tolerance to human errors, is likely to get public acceptance via demonstration of superb safety, lack of need for offsite response, and very good proliferation resistance. The ENHS reactor is designed to meet the requirements of Generation IV reactors including sustainable energy supply, low waste, high level of proliferation resistance, high level of safety and reliability, acceptable risk to capital and, hopefully, also competitive busbar cost of electricity.

  2. 星敏感器参数分析与自主校正%Star tracker parametric analysis for autonomous calibration

    Institute of Scientific and Technical Information of China (English)

    邢飞; 董瑛; 武延鹏; 尤政

    2005-01-01

    星敏感器焦距和主光轴偏心等参数对整个系统产生较大的影响.该文定量地分析了星敏感器星点坐标处理精度、主光轴位置和焦距误差对星图识别的影响,利用观星实验设计了一种自主进行参数校正的方法并给出了设计原则.对APS CMOS星敏感器进行了参数校正,并利用校正后的参数进行观星实验,星图识别成功率达到100%. 理论分析和实验结果表明,该方法可用于星敏感器的系统设计和参数的自主校正.

  3. Mounting Angle between Two Star Trackers in Combined Images Technique%组合星图技术中的双星敏感器安装角度分析

    Institute of Scientific and Technical Information of China (English)

    崔祥祥; 王宏力; 王永胜; 张勇; 何星; 陆敬辉

    2013-01-01

    Generally, two star trackers with small FOV (field-of-view) are used to maintain a high accuracy for micro-satellite’s attitude determination. Due to the small FOV, a sufficient number of stars for identification cannot be always captured. Combined images technique can be used to ease this problem, but its efficiency is highly affected by the mounting angle between two star trackers. The role made by the mounting angle is analyzed and simulated here. Results show that the number of guide starpairs matched to the reference angular distance changes like the sine function as the reference angular distance changes, and it reaches its extremum when the angular distance is about 90 degrees. And it increases as the tolerance increase. The extremum difference of the numbers of guide starpairs is highly affected by the tolerance. Therefore, the mounting angle should not be 90 degrees in combined images technique. The efficiency of the identification is higher as the mounting angle is smaller.%微小卫星一般使用两个小视场星敏感器以实现高精度姿态测量,但小视场容易导致观测星数量不足。组合星图技术可以缓解该问题,但其受星敏感器安装角度影响很大。分析了双星敏感器安装角度对组合星图识别效率的影响,并开展了仿真研究。实验结果表明:角距匹配得到的导航星对个数,随参考星对角距近似呈正弦函数变化,在约90°时达到极值;随容差增大而增大,且容差对导航星对个数极差影响很大。在组合星图技术中,双星敏感器应避免使用90°安装角,且安装角越小,组合星图识别效率越高。

  4. 捷联惯导基于星体跟踪器的高精度初始对准算法%Precise SINS initial alignment algorithm based on star tracker

    Institute of Scientific and Technical Information of China (English)

    张金亮; 秦永元; 吴枫

    2013-01-01

      捷联惯导与小视场星体跟踪器构成惯性/天文组合导航系统,导航精度受导航初始误差和器件误差的综合影响。基于此,提出一种捷联惯导与小视场星体跟踪器相组合的初始对准算法,对导航初始姿态误差和惯性器件误差进行估计修正。捷联惯导初始对准过程完成之后,在地面准静基座条件下做速度和位置阻尼条件下的惯导更新解算,利用捷联惯导系统的速度误差量测及小视场星体跟踪器的导航误差角测量量,设计组合粗对准算法和组合精对准算法,用于对捷联惯导系统的初始对准误差和惯性器件误差做进一步有效估计。仿真结果表明:对中等精度导航级捷联惯导系统,组合对准后水平姿态精度可提高到2',方位精度可提高到5'。%Inertial/celestial integrated navigation system, which is composed of SINS and star tracker, may be influenced by initial errors and inertial sensor errors. To solve this problem, an integrated initial alignment algorithm was proposed to estimate and correct the above errors. After self-alignment procedure, the SINS performs a designed navigation update algorithm in which the velocity and position is damped under stillness situation. Simultaneously, the star tracker measures and outputs the SINS’s navigation angel error. Then, by using SINS’s velocity outputs and star tracker’s angle error outputs as measurements, an integrated coarse alignment algorithm and corresponding fine alignment algorithm was deduced through a designed kalman filter, which could estimate both SINS’s initial navigation errors and IMU’s sensor errors. Simulation result shows that, for a SINS with medium precision, the level and azimuth precision of the integrated alignment algorithm can achieve 2' and 5' respectively.

  5. Development of a digital mobile solar tracker

    Science.gov (United States)

    Baidar, Sunil; Kille, Natalie; Ortega, Ivan; Sinreich, Roman; Thomson, David; Hannigan, James; Volkamer, Rainer

    2016-03-01

    We have constructed and deployed a fast digital solar tracker aboard a moving ground-based platform. The tracker consists of two rotating mirrors, a lens, an imaging camera, and a motion compensation system that provides the Euler angles of the mobile platform in real time. The tracker can be simultaneously coupled to UV-Vis and Fourier transform infrared spectrometers, making it a versatile tool to measure the absorption of trace gases using solar incoming radiation. The integrated system allows the tracker to operate autonomously while the mobile laboratory is in motion. Mobile direct sun differential optical absorption spectroscopy (mobile DS-DOAS) observations using this tracker were conducted during summer 2014 as part of the Front Range Air Pollution and Photochemistry Experiment (FRAPPE) in Colorado, USA. We demonstrate an angular precision of 0.052° (about 1/10 of the solar disk diameter) during research drives and verify this tracking precision from measurements of the center to limb darkening (CLD, the changing appearance of Fraunhofer lines) in the mobile DS-DOAS spectra. The high photon flux from direct sun observation enables measurements of nitrogen dioxide (NO2) slant columns with high temporal resolution and reveals spatial detail in the variations of NO2 vertical column densities (VCDs). The NO2 VCD from DS-DOAS is compared with a co-located MAX-DOAS instrument. Overall good agreement is observed amid a highly heterogeneous air mass.

  6. Development of a digital mobile solar tracker

    Directory of Open Access Journals (Sweden)

    S. Baidar

    2015-11-01

    Full Text Available We have constructed and deployed a fast digital solar tracker aboard a moving ground-based platform. The tracker consists of two rotating mirrors, a lens, an imaging camera, and a motion compensation system that provides the Euler angles of the mobile platform in real time. The tracker can be simultaneously coupled to UV-Vis and FTIR spectrometers making it a versatile tool to measure the absorption of trace gases using solar incoming radiation. The integrated system allows the tracker to operate autonomously while the mobile laboratory is in motion. Mobile direct sun Differential Optical Absorption Spectroscopy (mobile DS-DOAS observations using this tracker were conducted during summer 2014 as part of the Front Range Photochemistry and Pollution Experiment (FRAPPE in Colorado, USA. We demonstrate an angular precision of 0.052° (about 1/10 of the solar disk diameter during research drives, and verify this tracking precision from measurements of the center to limb darkening (CLD, the changing appearance of Fraunhofer lines in the mobile DS-DOAS spectra. The high photon flux from direct sun observation enables measurements of nitrogen dioxide (NO2 slant columns with high temporal resolution, and reveals spatial detail in the variations of NO2 vertical column densities (VCDs. The NO2 VCD from DS-DOAS is compared with a co-located MAX-DOAS instrument. Overall good agreement is observed amid a highly heterogeneous air mass.

  7. LHCb Upstream Tracker

    CERN Multimedia

    Gandini, P

    2014-01-01

    The LHCb upgrade requires replacing the silicon strip tracker between the vertex locator (VELO) and the magnet. A new design has been developed and tested based on the "stave" concept planned for the ATLAS upgrade

  8. LHCb Upstream Tracker

    CERN Multimedia

    Gandini, Paolo

    2014-01-01

    The LHCb upgrade requires replacing the silicon strip tracker between the vertex locator (VELO) and the magnet. A new design has been developed and tested based on the "stave" concept planned for the ATLAS upgrade.

  9. CMS Tracker Performance

    CERN Document Server

    Palmonari, Francesco

    2012-01-01

    particle trajectories as well as primary and secondary vertices, multi-step calibration procedures including module alignment are required. Results from operating the CMS tracker during the first two years of 7 TeV LHC collisions will be presented. These include aspects such as the data acquisition, detector slow control, and data quality monitoring. Projections for the evolution of the CMS tracker performance with increasing irradiation will be given.

  10. CMOS APS噪声对星斑质心定位精度的影响%CMOS APS Noise Effect on Position Accuracy of Star Tracker

    Institute of Scientific and Technical Information of China (English)

    史少龙; 尹达一

    2013-01-01

    CCD作为星敏感器探测器的技术已经比较成熟,但其瓶颈限制也日渐显露.本文以IBIS5-B-1300A探测器为例,具体分析CMOS APS各种噪声对星敏感器星像质心定位精度的影响,在理论上分析CMOS探测器所能达到的质心定位精度上限,并通过建模仿真验证理论分析结果,得出弥散斑束腰宽度为0.7,开窗大小为5×5时质心算法精度最高,固定模式噪声(FPN)对质心定位精度影响最大等结论,为星敏感器探测器的选型以及提高系统星点定位精度的潜力提供理论上的依据和支持.%The technology of CCD as a star sensor starlight detector has been very mature,but the bottleneck is becoming exposed.On the basis of parameters of IBIS5-B-1300A,the article analyzes CMOS APS noise effects on position accuracy of star sensor,obtains the maximum star position accuracy which a CMOS APS sensor can achieve and verifies the theoretical analysis results through modeling and simulation.Then two conclusions are drawn.First,when gauss dispersion radius is 0.7 and the windows size is 5 × 5,we can obtain optimized subpixel accuracy; Second,Fixed Pattern Noise(FPN) has the greatest effect on the accuracy of centroid algorithm.This article provides a theoretical basis and support for the selection of the starlight detector for a star sensor system.

  11. Operations of a non-stellar object tracker in space

    DEFF Research Database (Denmark)

    Riis, Troels; Jørgensen, John Leif; Betto, Maurizio

    1999-01-01

    The ability to detect and track non-stellar objects by utilizing a star tracker may seem rather straight forward, as any bright object, not recognized as a star by the system is a non stellar object. However, several pitfalls and errors exist, if a reliable and robust detection is required. To te...

  12. CMS silicon tracker developments

    Energy Technology Data Exchange (ETDEWEB)

    Civinini, C. E-mail: carlo.civinini@fi.infn.it; Albergo, S.; Angarano, M.; Azzi, P.; Babucci, E.; Bacchetta, N.; Bader, A.; Bagliesi, G.; Basti, A.; Biggeri, U.; Bilei, G.M.; Bisello, D.; Boemi, D.; Bosi, F.; Borrello, L.; Bozzi, C.; Braibant, S.; Breuker, H.; Bruzzi, M.; Buffini, A.; Busoni, S.; Candelori, A.; Caner, A.; Castaldi, R.; Castro, A.; Catacchini, E.; Checcucci, B.; Ciampolini, P.; Creanza, D.; D' Alessandro, R.; Da Rold, M.; Demaria, N.; De Palma, M.; Dell' Orso, R.; Della Marina, R.D.R.; Dutta, S.; Eklund, C.; Feld, L.; Fiore, L.; Focardi, E.; French, M.; Freudenreich, K.; Frey, A.; Fuertjes, A.; Giassi, A.; Giorgi, M.; Giraldo, A.; Glessing, B.; Gu, W.H.; Hall, G.; Hammarstrom, R.; Hebbeker, T.; Honma, A.; Hrubec, J.; Huhtinen, M.; Kaminsky, A.; Karimaki, V.; Koenig, St.; Krammer, M.; Lariccia, P.; Lenzi, M.; Loreti, M.; Luebelsmeyer, K.; Lustermann, W.; Maettig, P.; Maggi, G.; Mannelli, M.; Mantovani, G.; Marchioro, A.; Mariotti, C.; Martignon, G.; Evoy, B. Mc; Meschini, M.; Messineo, A.; Migliore, E.; My, S.; Paccagnella, A.; Palla, F.; Pandoulas, D.; Papi, A.; Parrini, G.; Passeri, D.; Pieri, M.; Piperov, S.; Potenza, R.; Radicci, V.; Raffaelli, F.; Raymond, M.; Santocchia, A.; Schmitt, B.; Selvaggi, G.; Servoli, L.; Sguazzoni, G.; Siedling, R.; Silvestris, L.; Starodumov, A.; Stavitski, I.; Stefanini, G.; Surrow, B.; Tempesta, P.; Tonelli, G.; Tricomi, A.; Tuuva, T.; Vannini, C.; Verdini, P.G.; Viertel, G.; Xie, Z.; Yahong, Li; Watts, S.; Wittmer, B

    2002-01-21

    The CMS Silicon tracker consists of 70 m{sup 2} of microstrip sensors which design will be finalized at the end of 1999 on the basis of systematic studies of device characteristics as function of the most important parameters. A fundamental constraint comes from the fact that the detector has to be operated in a very hostile radiation environment with full efficiency. We present an overview of the current results and prospects for converging on a final set of parameters for the silicon tracker sensors.

  13. Model of CMS Tracker

    CERN Multimedia

    Breuker

    1999-01-01

    A full scale CMS tracker mock-up exposed temporarily in the hall of building 40. The purpose of the mock-up is to study the routing of services, assembly and installation. The people in front are only a small fraction of the CMS tracker collaboration. Left to right : M. Atac, R. Castaldi, H. Breuker, D. Pandoulas,P. Petagna, A. Caner, A. Carraro, H. Postema, M. Oriunno, S. da Mota Silva, L. Van Lancker, W. Glessing, G. Benefice, A. Onnela, M. Gaspar, G. M. Bilei

  14. LHCb Silicon Tracker infrastructure

    CERN Document Server

    Ermoline, Yuri

    2004-01-01

    The LHCb Silicon Tracker is a vital part of the experiment. It consists of four planar stations: one trigger and three inner tracking stations. The operation of the Silicon Tracker detectors and electronics is provided by its infrastructure: cooling system, high- and low-voltage power supply systems, temperature and radiation monitoring systems. Several components of these systems are located in the experimental hall and subjected to radiation. This paper mainly concentrates on the recent development: requirements definition, evaluation of possible implementation scenarios, component choice and component radiation tests.

  15. LHCb Upgrade: Upstream Tracker

    CERN Document Server

    AUTHOR|(CDS)2082337

    2015-01-01

    The upgraded LHCb detector will run at an instantaneous luminosity of 2 X 10$^{33}$ cm$^{-2}$ s$^{-1}$, five times higher than in the current configuration, and will have a full 40 MHz readout. In order to cope with these higher instantaneous rates, the tracking detector upstream of the LHCb dipole magnet, called Tracker Turicensis (TT) [1], will be replaced by the Upstream Tracker (UT) [2]. The conceptual design of the UT and the current status of the R&D are presented here.

  16. LHCb: LHCb Upstream Tracker

    CERN Multimedia

    Manning Jr, P; Stone, S

    2014-01-01

    The LHCb upgrade requires replacing the silicon strip tracker between the vertex locator and the magnet. A new design has been developed and tested based on the "stave" concept planned for the ATLAS upgrade. We will describe the new detector being constructed and show its improved performance in charged particle tracking and triggering.

  17. Rotational Dynamics with Tracker

    Science.gov (United States)

    Eadkhong, T.; Rajsadorn, R.; Jannual, P.; Danworaphong, S.

    2012-01-01

    We propose the use of Tracker, freeware for video analysis, to analyse the moment of inertia ("I") of a cylindrical plate. Three experiments are performed to validate the proposed method. The first experiment is dedicated to find the linear coefficient of rotational friction ("b") for our system. By omitting the effect of such friction, we derive…

  18. Teaching Astronomy Using Tracker

    Science.gov (United States)

    Belloni, Mario; Christian, Wolfgang; Brown, Douglas

    2013-01-01

    A recent paper in this journal presented a set of innovative uses of video analysis for introductory physics using Tracker. In addition, numerous other papers have described how video analysis can be a meaningful part of introductory courses. Yet despite this, there are few resources for using video analysis in introductory astronomy classes. In…

  19. Prototype ATLAS straw tracker

    CERN Multimedia

    Laurent Guiraud

    1998-01-01

    This is an early prototype of the straw tracking device for the ATLAS detector at CERN. This detector will be part of the LHC project, scheduled to start operation in 2008. The straw tracker will consist of thousands of gas-filled straws, each containing a wire, allowing the tracks of particles to be followed.

  20. MediaTracker system

    International Nuclear Information System (INIS)

    The initial objectives of this effort were to provide a hardware and software platform that can address the requirements for the accountability of classified removable electronic media and vault access logging. The Media Tracker system software assists classified media custodian in managing vault access logging and Media Tracking to prevent the inadvertent violation of rules or policies for the access to a restricted area and the movement and use of tracked items. The MediaTracker system includes the software tools to track and account for high consequence security assets and high value items. The overall benefits include: (1) real-time access to the disposition of all Classified Removable Electronic Media (CREM), (2) streamlined security procedures and requirements, (3) removal of ambiguity and managerial inconsistencies, (4) prevention of incidents that can and should be prevented, (5) alignment with the DOE's initiative to achieve improvements in security and facility operations through technology deployment, and (6) enhanced individual responsibility by providing a consistent method of dealing with daily responsibilities. In response to initiatives to enhance the control of classified removable electronic media (CREM), the Media Tracker software suite was developed, piloted and implemented at the Los Alamos National Laboratory beginning in July 2000. The Media Tracker software suite assists in the accountability and tracking of CREM and other high-value assets. One component of the MediaTracker software suite provides a Laboratory-approved media tracking system. Using commercial touch screen and bar code technology, the MediaTracker (MT) component of the MediaTracker software suite provides an efficient and effective means to meet current Laboratory requirements and provides new-engineered controls to help assure compliance with those requirements. It also establishes a computer infrastructure at vault entrances for vault access logging, and can accommodate

  1. Two ATLAS trackers become one

    CERN Multimedia

    2006-01-01

    The ATLAS inner detector barrel comes one step closer to completion as the semiconductor tracker is merged with the transition radiation tracker. ATLAS collaborators prepare for the insertion of the semiconductor tracker (SCT, behind) into the transition radiation tracker (TRT, in front). Some had hoped it would fall on Valentine's Day. But despite the slight delay, Friday 17 February was lovingly embraced as 'Conception Day,' when dozens of physicists and engineers from the international collaboration gathered to witness the insertion of the ATLAS semiconductor tracker into the transition radiation tracker, a major milestone in the assembly of the experiment's inner detector. With just millimeters of room for error, the cylindrical trackers were slid into each other as inner detector integration coordinator Heinz Pernegger issued commands and scientists held out flashlights, lay on their backs and stood on ladders to take careful measurements. Each tracker is the result of about 10 years of international ...

  2. A Survey on Star Identification Algorithms

    OpenAIRE

    Daniele Mortari; Benjamin B. Spratling

    2009-01-01

    The author surveys algorithms used in star identification, commonly used in star trackers to determine the attitude of a spacecraft. Star trackers are a staple of attitude determination systems for most types of satellites. The paper covers: (a) lost-in-space algorithms (when no a priori attitude information is available), (b) recursive algorithms (when some a priori attitude information is available), and (c) non-dimensional algorithms (when the star tracker calibration is not well-known). T...

  3. Star tracker ground calibration based on the invariant of interstar angles%利用星角距不变性标定星敏感器内部参数

    Institute of Scientific and Technical Information of China (English)

    刘海波; 王文学; 陈圣义; 苏昂; 张小虎

    2014-01-01

    A calibration approach based on the invariant of interstar angles was put forward for star trackers.Compared with common approaches,the sine of interstar angle which provides greater sensitivity for the angle changes closed to 0°was adopted to construct the observation equation instead of its cosine.In the calibration procedure,the two-step approach was proposed to estimate the principal point,focal length,and distortion parameters.The iterative optimization was also proposed to get the optimal estimations.In order to improve the accuracy of calibration, the apparent position of star at the observing time was modified.The experimental results indicate that the sine method is more accurate;and the deviation root-mean-square of the measured interstar angle is 2.2 ×10 -5 rad after calibrated.%提出了一种恒星角距不变的星敏感器内部参数的地面标定方法。较常见的星角距的标定方法不同的是,该方法利用对在0°附近的角度变化较敏感的恒星角距的正弦值建立观测方程;采用两步法分别估计焦距、主点和高阶畸变系数,并采用迭代优化的方法,获得最优估计值。为了确保标定精度,对观测时刻的导航星进行了视位置的修正。实验结果表明,采用星角距的正弦值建立观测方程,估计精度较高,采用考虑高阶畸变的改进正弦法标定后的星角距误差的均方根值为2.2×10-5 rad。

  4. LHCb upstream tracker

    CERN Multimedia

    Artuso, Marina

    2016-01-01

    The detector for the LHCb upgrade is designed for 40MHz readout, allowing the experiment to run at an instantaneous luminosity of 2x10^33 cm$^2$s$^-1$. The upgrade of the tracker subsystem in front of the dipole magnet, the Upstream Tracker, is crucial for charged track reconstruction and fast trigger decisions based on a tracking algorithm involving also vertex detector information. The detector consists of 4 planes with a total area of about 8.5m$^2$, made of single sided silicon strip sensors read-out by a novel custom-made ASIC (SALT). Details on the performance of prototype sensors, front-end electronics, near-detector electronics and mechanical components are presented.

  5. The CMS silicon tracker

    Energy Technology Data Exchange (ETDEWEB)

    Focardi, E. E-mail: focardi@pi.infn.it; Albergo, S.; Angarano, M.; Azzi, P.; Babucci, E.; Bacchetta, N.; Bader, A.; Bagliesi, G.; Basti, A.; Biggeri, U.; Bilei, G.M.; Bisello, D.; Boemi, D.; Bosi, F.; Borrello, L.; Bozzi, C.; Braibant, S.; Breuker, H.; Bruzzi, M.; Buffini, A.; Busoni, S.; Candelori, A.; Caner, A.; Castaldi, R.; Castro, A.; Catacchini, E.; Checcucci, B; Ciampolini, P.; Civinini, C.; Creanza, D.; D' Alessandro, R.; Da Rold, M.; Demaria, N.; De Palma, M.; Dell' Orso, R.; Della Marina, R.; Dutta, S.; Eklund, C.; Feld, L.; Fiore, L.; French, M.; Freudenreich, K.; Frey, A.; Fuertjes, A.; Giassi, A.; Giorgi, M.; Giraldo, A.; Glessing, B.; Gu, W.H.; Hall, G.; Hammarstrom, R.; Hebbeker, T.; Honma, A.; Hrubec, J.; Huhtinen, M.; Kaminsky, A.; Karimaki, V.; Koenig, St.; Krammer, M.; Lariccia, P.; Lenzi, M.; Loreti, M.; Leubelsmeyer, K.; Lustermann, W.; Maettig, P.; Maggi, G.; Mannelli, M.; Mantovani, G.; Marchioro, A.; Mariotti, C.; Martignon, G.; Evoy, B.Mc; Meschini, M.; Messineo, A.; Migliore, E.; My, S.; Paccagnella, A.; Palla, F.; Pandoulas, D.; Papi, A.; Parrini, G.; Passeri, D.; Pieri, M.; Piperov, S.; Potenza, R.; Radicci, V.; Raffaelli, F.; Raymond, M.; Rizzo, F.; Santocchia, A.; Schmitt, B.; Selvaggi, G.; Servoli, L.; Sguazzoni, G.; Siedling, R.; Silvestris, L.; Starodumov, A.; Stavitski, I.; Stefanini, G.; Surrow, B.; Tempesta, P.; Tonelli, G.; Tricomi, A.; Tuuva, T.; Vannini, C.; Verdini, P.G.; Viertel, G.; Xie, Z.; Yahong, Li; Watts, S.; Wittmer, B

    2000-10-11

    This paper describes the Silicon microstrip Tracker of the CMS experiment at LHC. It consists of a barrel part with 5 layers and two endcaps with 10 disks each. About 10 000 single-sided equivalent modules have to be built, each one carrying two daisy-chained silicon detectors and their front-end electronics. Back-to-back modules are used to read-out the radial coordinate. The tracker will be operated in an environment kept at a temperature of T=-10 deg. C to minimize the Si sensors radiation damage. Heavily irradiated detectors will be safely operated due to the high-voltage capability of the sensors. Full-size mechanical prototypes have been built to check the system aspects before starting the construction.

  6. CMS Tracker Visualisation

    CERN Document Server

    Mennea, Maria Santa; Zito, Giuseppe

    2004-01-01

    To provide improvements in the performance of existing tracker data visualization tools in IGUANA, a 2D visualisation software has been developed, using the object oriented paradigm and software engineering techniques. We have designed 2D graphics objects and some of them have been implemented. The access to the new objects is made in ORCA plugin of IGUANA CMS. A new tracker object oriented model has been designed for developing these 2D graphics objects. The model consists of new classes which represent all its components (layers, modules, rings, petals, rods).The new classes are described here. The last part of this document contains a user manual of the software and will be updated with new releases.

  7. Robust correlation tracker

    Indian Academy of Sciences (India)

    M Sankar Kishore; K Veerabhadra Rao

    2001-06-01

    Correlation tracking plays an important role in the automation of weapon systems. Area correlation is an effective technique for tracking targets that have neither prominent features nor high contrast with the background and the ‘target’ can even be an area or a scene of interest. Even though this technique is robust under varying conditions of target background and light conditions, it has some problems like target drift and false registration. When the tracker or target is moving, the registration point drifts due to the discrete pixel size and aspect angle change. In this research work, an attempt has been made to improve the performance of a correlation tracker for tracking ground targets with very poor contrast. In the present work only the CCD visible images with very poor target to background contrast are considered. Applying novel linear and nonlinear filters, the problems present in the correlation tracker are overcome. Confidence and redundancy measures have been proposed to improve the performance by detecting misregistration. The proposed algorithm is tested on different sequences of images and its performance is satisfactory.

  8. A quadrant-CCD star tracker

    Science.gov (United States)

    Clampin, M.; Durrance, S. T.; Barkhouser, R.; Golimowski, D. A.; Wald, A.; Fastie, W. G.; Heidtmann, D. L.; Blouke, Morley M.; Westphal, James A.; Janesick, James R.

    1990-01-01

    The characteristics of a quadrant-CCD designed for pointing and tracking are discussed with reference to its use in an adaptive optics program. The quadrant-CCD is used to correct stellar image motion proceeding from atmospheric turbulence by means of a system in which a sensor measures the image offset and sends data to a high-speed tip/tilt mirror. The design and control of the device are detailed, including four 100-micron-square pixels, the quadrant architecture, controller electronics, and data acquisition computer and interface. The transfer function is set forth in the x and y directions, and transfer curves are shown. A laboratory simulation of random image motion was conducted to evaluate the performance of the quadrant-CCD as an image motion sensor, and the experimental results are presented. The suitability of the quadrant-CCD for space-based pointing and tracking uses is demonstrated by this test and two earlier theoretical studies. Some future developments which improve performance capabilities are mentioned.

  9. The Proba Satellite Star Tracker Performance

    DEFF Research Database (Denmark)

    Jørgensen, John Leif; Denver, Troelz; Betto, Maurizio;

    2005-01-01

    ESA's PROBA satellite features a high degree of autonomy, both technologically and scientifically. It is build around a powerful command, data and AOCS controller and with its less than 100 kg it is a true microsatellite. The scientific mission of PROBA includes a scanning telescope, which calls ...

  10. Millisecond X-ray Star Tracker Project

    Data.gov (United States)

    National Aeronautics and Space Administration — CrossTrac Engineering, in cooperation with its subcontractors Dr Suneel Sheikh of ASTER Labs, Inc, and Mr Paul Graven of Cateni, Inc, proposes to develop a next...

  11. Precision High Altitude Star Tracker Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Motivation: The long, successful history of scientific ballooning, coupled with tightening budgets, has led to a surge of interest in the scientific potential of...

  12. CMS tracker visualization tools

    CERN Document Server

    Zito, G; Osborne, I; Regano, A

    2005-01-01

    This document will review the design considerations, implementations and performance of the CMS Tracker Visualization tools. In view of the great complexity of this sub-detector (more than 50 millions channels organized in 16540 modules each one of these being a complete detector), the standard CMS visualization tools (IGUANA and IGUANACMS) that provide basic 3D capabilities and integration within CMS framework, respectively, have been complemented with additional 2D graphics objects. Based on the experience acquired using this software to debug and understand both hardware and software during the construction phase, we propose possible future improvements to cope with online monitoring and event analysis during data taking.

  13. CMS tracker visualization tools

    Energy Technology Data Exchange (ETDEWEB)

    Mennea, M.S. [Dipartimento Interateneo di Fisica ' Michelangelo Merlin' e INFN sezione di Bari, Via Amendola 173 - 70126 Bari (Italy); Osborne, I. [Northeastern University, 360 Huntington Avenue, Boston, MA 02115 (United States); Regano, A. [Dipartimento Interateneo di Fisica ' Michelangelo Merlin' e INFN sezione di Bari, Via Amendola 173 - 70126 Bari (Italy); Zito, G. [Dipartimento Interateneo di Fisica ' Michelangelo Merlin' e INFN sezione di Bari, Via Amendola 173 - 70126 Bari (Italy)]. E-mail: giuseppe.zito@ba.infn.it

    2005-08-21

    This document will review the design considerations, implementations and performance of the CMS Tracker Visualization tools. In view of the great complexity of this sub-detector (more than 50 millions channels organized in 16540 modules each one of these being a complete detector), the standard CMS visualization tools (IGUANA and IGUANACMS) that provide basic 3D capabilities and integration within CMS framework, respectively, have been complemented with additional 2D graphics objects. Based on the experience acquired using this software to debug and understand both hardware and software during the construction phase, we propose possible future improvements to cope with online monitoring and event analysis during data taking.

  14. CMS tracker observes muons

    CERN Multimedia

    2006-01-01

    A computer image of a cosmic ray traversing the many layers of the TEC+ silicon sensors. The first cosmic muon tracks have been observed in one of the CMS tracker endcaps. On 14 March, a sector on one of the two large tracker endcaps underwent a cosmic muon run. Since then, thousands of tracks have been recorded. These data will be used not only to study the tracking, but also to exercise various track alignment algorithms The endcap tested, called the TEC+, is under construction at RWTH Aachen in Germany. The endcaps have a modular design, with silicon strip modules mounted onto wedge-shaped carbon fibre support plates, so-called petals. Up to 28 modules are arranged in radial rings on both sides of these plates. One eighth of an endcap is populated with 18 petals and called a sector. The next major step is a test of the first sector at CMS operating conditions, with the silicon modules at a temperature below -10°C. Afterwards, the remaining seven sectors have to be integrated. In autumn 2006, TEC+ wil...

  15. The ATLAS semiconductor tracker

    CERN Document Server

    Mikuz, Marko

    2003-01-01

    The ATLAS Semiconductor Tracker (SCT) is presented. About 16000 silicon micro-strip sensors with a total active surface of over 60 m **2 and with 6.3 million read-out channels are built into 4088 modules arranged into four barrel layers and nine disks covering each of the forward regions up to an eta of 2.5. Challenges are imposed by the hostile radiation environment with particle fluences up to 2 multiplied by 10**1**4 cm**-**2 1 MeV neutron NIEL equivalent and 100 kGy TID, the 25 ns LHC bunch crossing time and the need for a hermetic, lightweight tracker. The solution adopted is carefully designed strip detectors operated at -7 degree C, biased up to 500 V and read out by binary radhard fast BiCMOS electronics. A zero-CTE carbon fibre structure provides mechanical support. 30 kW of power are supplied on aluminiutn/Kapton tapes and cooled by C//3F//8 evaporative cooling. Data and commands are transferred by optical links. Prototypes of detector modules have been built, irradiated to the maximum expected flue...

  16. The ATLAS Fast Tracker

    CERN Document Server

    Volpi, Guido; The ATLAS collaboration

    2015-01-01

    The use of tracking information at the trigger level in the LHC Run II period is crucial for the trigger an data acquisition (TDAQ) system. The tracking precision is in fact important to identify specific decay products of the Higgs boson or new phenomena, a well as to distinguish the contributions coming from many contemporary collisions that occur at every bunch crossing. However, the track reconstruction is among the most demanding tasks performed by the TDAQ computing farm; in fact, full reconstruction at full Level-1 trigger accept rate (100 KHz) is not possible. In order to overcome this limitation, the ATLAS experiment is planning the installation of a specific processor: the Fast Tracker (FTK), which is aimed at achieving this goal. The FTK is a pipeline of high performance electronic, based on custom and commercial devices, which is expected to reconstruct, with high resolution, the trajectories of charged tracks with a transverse momentum above 1 GeV, using the ATLAS inner tracker information. Patte...

  17. Robotics Vision-Based System of Autonomous Underwater Vehicle for an Underwater Pipeline Tracker%自主式水下机器人的光视觉管道探测跟踪系统

    Institute of Scientific and Technical Information of China (English)

    曾文静; 徐玉如; 万磊; 张铁栋

    2012-01-01

    The detection and tracking of underwater pipeline based on monocular vision system of AUV(autonomous underwater vehicle) were addressed.An integrated vision system including software and hardware structure was designed.The feature of underwater pipeline image was analyzed and according to that,corresponding pre-processing method was proposed.An improved Hough transforming was advanced to obtain pipeline contour.Pipeline reference zone was estimated to increase the accuracy and decrease the time cost of pipeline tracking.Finally,the system was validated to be effective and feasible through the tank experiments.%研究了自主式水下机器人(AUV)利用单目光视觉系统对水下管道的检测跟踪问题,对实现该方法的各个过程从硬件组成和软件体系结构两方面进行了阐述,从而完成了一整套水下光视觉系统的软、硬件设计.分析了水下管道图像的特点,结合该特点阐述了图像预处理过程,提出了一种改进的Hough变换方法,改善了管道边界的提取效果.同时采用管道参考区域预测方法,提高了管道的检测率以及实时性,并利用水池试验对系统的可行性和有效性进行了验证.

  18. ILC Vertex Tracker R&D

    Energy Technology Data Exchange (ETDEWEB)

    Battaglia, Marco; Bussat, Jean-Marie; Contarato, Devis; Denes,Peter; Glesener, Lindsay; Greiner, Leo; Hooberman, Benjamin; Shuman,Derek; Tompkins, Lauren; Vu, Chinh; Bisello, Dario; Giubilato, Piero; Pantano, Devis; Costa, Marco; La Rosa, Alessandro; Bolla, Gino; Bortoletto, Daniela; Children, Isaac

    2007-10-01

    This document summarizes past achievements, current activities and future goals of the R&D program aimed at the design, prototyping and characterization of a full detector module, equipped with monolithic pixel sensors, matching the requirements for the Vertex Tracker at the ILC. We provide a plan of activities to obtain a demonstrator multi-layered vertex tracker equipped with sensors matching the ILC requirements and realistic lightweight ladders in FY11, under the assumption that ILC detector proto-collaborations will be choosing technologies and designs for the Vertex Tracker by that time. The R&D program discussed here started at LBNL in 2004, supported by a Laboratory Directed R&D (LDRD) grant and by funding allocated from the core budget of the LBNL Physics Division and from the Department of Physics at UC Berkeley. Subsequently additional funding has been awarded under the NSF-DOE LCRD program and also personnel have become available through collaborative research with other groups. The aim of the R&D program carried out by our collaboration is to provide a well-integrated, inclusive research effort starting from physics requirements for the ILC Vertex Tracker and addressing Si sensor design and characterization, engineered ladder design, module system issues, tracking and vertex performances and beam test validation. The broad scope of this program is made possible by important synergies with existing know-how and concurrent programs both at LBNL and at the other collaborating institutions. In particular, significant overlaps with LHC detector design, SLHC R&D as well as prototyping for the STAR upgrade have been exploited to optimize the cost per deliverable of our program. This activity is carried out as a collaborative effort together with Accelerator and Fusion Research, the Engineering and the Nuclear Science Divisions at LBNL, INFN and the Department of Physics in Padova, Italy, INFN and the Department of Physics in Torino, Italy and the Department

  19. The LHCb Silicon Tracker

    Science.gov (United States)

    Tobin, Mark

    2016-09-01

    The LHCb experiment is dedicated to the study of heavy flavour physics at the Large Hadron Collider (LHC). The primary goal of the experiment is to search for indirect evidence of new physics via measurements of CP violation and rare decays of beauty and charm hadrons. The LHCb detector has a large-area silicon micro-strip detector located upstream of a dipole magnet, and three tracking stations with silicon micro-strip detectors in the innermost region downstream of the magnet. These two sub-detectors form the LHCb Silicon Tracker (ST). This paper gives an overview of the performance and operation of the ST during LHC Run 1. Measurements of the observed radiation damage are shown and compared to the expectation from simulation.

  20. A silicon tracker for Christmas

    CERN Multimedia

    2008-01-01

    The CMS experiment installed the world’s largest silicon tracker just before Christmas. Marcello Mannelli: physicist and deputy CMS project leader, and Alan Honma, physicist, compare two generations of tracker: OPAL for the LEP (at the front) and CMS for the LHC (behind). There is quite a difference between 1m2 and 205m2.. CMS received an early Christmas present on 18 December when the silicon tracker was installed in the heart of the CMS magnet. The CMS tracker team couldn’t have hoped for a better present. Carefully wrapped in shiny plastic, the world’s largest silicon tracker arrived at Cessy ready for installation inside the CMS magnet on 18 December. This rounded off the year for CMS with a major event, the crowning touch to ten years of work on the project by over five hundred scientists and engineers. "Building a scientific instrument of this size and complexity is a huge technical a...

  1. Mechatronic Prototype of Parabolic Solar Tracker.

    Science.gov (United States)

    Morón, Carlos; Díaz, Jorge Pablo; Ferrández, Daniel; Ramos, Mari Paz

    2016-01-01

    In the last 30 years numerous attempts have been made to improve the efficiency of the parabolic collectors in the electric power production, although most of the studies have focused on the industrial production of thermoelectric power. This research focuses on the application of this concentrating solar thermal power in the unexplored field of building construction. To that end, a mechatronic prototype of a hybrid paraboloidal and cylindrical-parabolic tracker based on the Arduido technology has been designed. The prototype is able to measure meteorological data autonomously in order to quantify the energy potential of any location. In this way, it is possible to reliably model real commercial equipment behavior before its deployment in buildings and single family houses. PMID:27314359

  2. Mechatronic Prototype of Parabolic Solar Tracker.

    Science.gov (United States)

    Morón, Carlos; Díaz, Jorge Pablo; Ferrández, Daniel; Ramos, Mari Paz

    2016-06-15

    In the last 30 years numerous attempts have been made to improve the efficiency of the parabolic collectors in the electric power production, although most of the studies have focused on the industrial production of thermoelectric power. This research focuses on the application of this concentrating solar thermal power in the unexplored field of building construction. To that end, a mechatronic prototype of a hybrid paraboloidal and cylindrical-parabolic tracker based on the Arduido technology has been designed. The prototype is able to measure meteorological data autonomously in order to quantify the energy potential of any location. In this way, it is possible to reliably model real commercial equipment behavior before its deployment in buildings and single family houses.

  3. Mechatronic Prototype of Parabolic Solar Tracker

    Directory of Open Access Journals (Sweden)

    Carlos Morón

    2016-06-01

    Full Text Available In the last 30 years numerous attempts have been made to improve the efficiency of the parabolic collectors in the electric power production, although most of the studies have focused on the industrial production of thermoelectric power. This research focuses on the application of this concentrating solar thermal power in the unexplored field of building construction. To that end, a mechatronic prototype of a hybrid paraboloidal and cylindrical-parabolic tracker based on the Arduido technology has been designed. The prototype is able to measure meteorological data autonomously in order to quantify the energy potential of any location. In this way, it is possible to reliably model real commercial equipment behavior before its deployment in buildings and single family houses.

  4. The PAMELA silicon tracker

    Energy Technology Data Exchange (ETDEWEB)

    Straulino, S. E-mail: straulino@fi.infn.it; Adriani, O.; Bonechi, L.; Bongi, M.; Castellini, G.; D' Alessandro, R.; Gabbanini, A.; Grandi, M.; Papini, P.; Ricciarini, S.B.; Spillantini, P.; Taccetti, F.; Tesi, M.; Vannuccini, E

    2004-09-01

    The silicon tracker of the PAMELA apparatus has been assembled and it is ready to fly on-board the Russian satellite Resurs DK for a 3-year mission. The experiment will study, mainly, spectra of particles and antiparticles in cosmic rays. The magnetic spectrometer's primary goal is to precisely measure momenta of charged particles, whose trajectories have been bent by a permanent magnet. The detector is composed of 6 planes of double-sided silicon microstrip detectors, inserted between adjacent modules of a permanent magnet which produces an almost uniform magnetic field inside a rectangular cavity that particles cross. The spatial resolution of the detectors is about 3 {mu}m for the bending coordinate. The development of such detectors required a complex manufacturing procedure in order to preserve the physical performance in a device suitable for a space mission. In the construction phase data originating from both beam tests and simulation helped to check the detector's characteristics and to optimize the achievable spatial resolution. The development and the final assembling of these detectors are described in this paper.

  5. The CMS Silicon Tracker Alignment

    CERN Document Server

    Castello, R

    2008-01-01

    The alignment of the Strip and Pixel Tracker of the Compact Muon Solenoid experiment, with its large number of independent silicon sensors and its excellent spatial resolution, is a complex and challenging task. Besides high precision mounting, survey measurements and the Laser Alignment System, track-based alignment is needed to reach the envisaged precision.\\\\ Three different algorithms for track-based alignment were successfully tested on a sample of cosmic-ray data collected at the Tracker Integration Facility, where 15\\% of the Tracker was tested. These results, together with those coming from the CMS global run, will provide the basis for the full-scale alignment of the Tracker, which will be carried out with the first \\emph{p-p} collisions.

  6. ATLAS semiconductor tracker installed into its barrel

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    The ATLAS silicon tracker is installed in the silicon tracker barrel. Absolute precision was required in this operation to ensure that the tracker was inserted without damage through minimal clearance. The installation was performed in a clean room on the CERN site so that no impurities in the air would contaminate the tracker's systems.

  7. [Autonomic neuropathies].

    Science.gov (United States)

    Siepmann, T; Penzlin, A I; Illigens, B M W

    2013-07-01

    Autonomic neuropathies are a heterogeneous group of diseases that involve damage of small peripheral autonomic Aδ- and C-fibers. Causes of autonomic nerve fiber damage are disorders such as diabetes mellitus and HIV-infection. Predominant symptoms of autonomic neuropathy are orthostatic hypotension, gastro-intestinal problems, urogenital dysfunction, and cardiac arrhythmia, which can severely impair the quality of life in affected patients. Furthermore, autonomic neuropathies can be induced by autoimmune diseases such as acute inflammatory demyelinating polyneuropathy, hereditary disorders such as the lysosomal storage disorder Fabry disease and hereditary sensory and autonomic neuropathies, as well as certain toxins and drugs.

  8. Agent, autonomous

    OpenAIRE

    Luciani, Annie

    2007-01-01

    The expression autonomous agents, widely used in virtual reality, computer graphics, artificial intelligence and artificial life, corresponds to the simulation of autonomous creatures, virtual (i.e. totally computed by a program), or embodied in a physical envelope, as done in autonomous robots.

  9. A Survey on Star Identification Algorithms

    Directory of Open Access Journals (Sweden)

    Daniele Mortari

    2009-01-01

    Full Text Available The author surveys algorithms used in star identification, commonly used in star trackers to determine the attitude of a spacecraft. Star trackers are a staple of attitude determination systems for most types of satellites. The paper covers: (a lost-in-space algorithms (when no a priori attitude information is available, (b recursive algorithms (when some a priori attitude information is available, and (c non-dimensional algorithms (when the star tracker calibration is not well-known. The performance of selected algorithms and supporting algorithms are compared.

  10. Chapter 6: CPV Tracking and Trackers

    Energy Technology Data Exchange (ETDEWEB)

    Luque-Heredia, Ignacio; Magalhaes, Pedro; Muller, Matthew

    2016-04-15

    This chapter explains the functional requirements of a concentrator photovoltaic (CPV) sun tracker. It derives the design specifications of a CPV tracker. The chapter presents taxonomy of trackers describing the most common tracking architectures, based on the number of axes, their relative position, and the foundation and placing of tracking drives. It deals with the structural issues related to tracker design, mainly related to structural flexure and its impact on the system's acceptance angle. The chapter analyzes the auto-calibrated sun tracking control, by describing the state of the art and its development background. It explores the sun tracking accuracy measurement with a practical example. The chapter discusses tracker manufacturing and tracker field works. It reviews survey of different types of tracker designs obtained from different manufacturers. Finally, the chapter deals with IEC62817, the technical standard developed for CPV sun trackers.

  11. Mechanical stability of the CMS Tracker

    CERN Document Server

    CMS Collaboration

    2015-01-01

    reconstructs the absolute position of individual detector modules with a similar accuracy but after days of data taking. During the long term operation at fixed temperature of +4$^o$C in years 2011--2013 the alignment of tracker components was stable within 10 microns. Temperature variations in the Tracker volume are found to cause the displacements of tracker structures of abou...

  12. LHCb Upgrade: Scintillating Fibre Tracker

    Science.gov (United States)

    Tobin, Mark

    2016-07-01

    The LHCb detector will be upgraded during the Long Shutdown 2 (LS2) of the LHC in order to cope with higher instantaneous luminosities and to read out the data at 40 MHz using a trigger-less read-out system. All front-end electronics will be replaced and several sub-detectors must be redesigned to cope with higher occupancy. The current tracking detectors downstream of the LHCb dipole magnet will be replaced by the Scintillating Fibre (SciFi) Tracker. The SciFi Tracker will use scintillating fibres read out by Silicon Photomultipliers (SiPMs). State-of-the-art multi-channel SiPM arrays are being developed to read out the fibres and a custom ASIC will be used to digitise the signals from the SiPMs. The evolution of the design since the Technical Design Report in 2014 and the latest R & D results are presented.

  13. Introduction to Mini Muon Tracker

    Energy Technology Data Exchange (ETDEWEB)

    Borozdin, Konstantin N. [Los Alamos National Laboratory

    2012-08-13

    Using a mini muon tracker developed at the Los Alamos National Laboratory we performed experiments of simple landscapes of various materials, including TNT, 9501, lead, tungsten, aluminium, and water. Most common scenes are four two inches thick step wedges of different dimensions: 12-inch x 12-inch, 12-inch x 9-inch, 12-inch x 6-inch, and 12-inch x 3-inch; and a one three inches thick hemisphere of lead with spherical hollow, and a similar full lead sphere.

  14. Activity trackers: a critical review.

    Science.gov (United States)

    Lee, Jeon; Finkelstein, Joseph

    2014-01-01

    The wearable consumer health devices can be mainly divided into activity trackers, sleep trackers, and stress management devices. These devices are widely advertised to provide positive effects on the user's daily behaviours and overall heath. However, objective evidence supporting these claims appears to be missing. The goal of this study was to review available evidence pertaining to performance of activity trackers. A comprehensive review of available information has been conducted for seven representative devices and the validity of marketing claims was assessed. The device assessment was based on availability of verified output metrics, theoretical frameworks, systematic evaluation, and FDA clearance. The review identified critical absence of supporting evidence of advertised functions and benefits for the majority of the devices. Six out of seven devices did not provide any information on sensor accuracy and output validity at all. Possible underestimation or overestimation of specific health indicators reported to consumers was not clearly disclosed to the public. Furthermore, significant limitations of these devices which can be categorized into user restrictions, user responsibilities and company disclaimers could not be easily found or comprehended by unsophisticated users and may represent a serious health hazard. PMID:25160247

  15. Activity trackers: a critical review.

    Science.gov (United States)

    Lee, Jeon; Finkelstein, Joseph

    2014-01-01

    The wearable consumer health devices can be mainly divided into activity trackers, sleep trackers, and stress management devices. These devices are widely advertised to provide positive effects on the user's daily behaviours and overall heath. However, objective evidence supporting these claims appears to be missing. The goal of this study was to review available evidence pertaining to performance of activity trackers. A comprehensive review of available information has been conducted for seven representative devices and the validity of marketing claims was assessed. The device assessment was based on availability of verified output metrics, theoretical frameworks, systematic evaluation, and FDA clearance. The review identified critical absence of supporting evidence of advertised functions and benefits for the majority of the devices. Six out of seven devices did not provide any information on sensor accuracy and output validity at all. Possible underestimation or overestimation of specific health indicators reported to consumers was not clearly disclosed to the public. Furthermore, significant limitations of these devices which can be categorized into user restrictions, user responsibilities and company disclaimers could not be easily found or comprehended by unsophisticated users and may represent a serious health hazard.

  16. Autonomic neuropathy

    DEFF Research Database (Denmark)

    Hilsted, J

    1983-01-01

    The diagnosis of autonomic neuropathy is often difficult to establish, since clinical symptoms generally appear late in the course of the disease, and may be non-specific. A number of recently developed quantifiable and reproducible autonomic nerve function tests are reviewed, with emphasis on th...

  17. Autonomic neuropathy

    DEFF Research Database (Denmark)

    Hilsted, J

    1980-01-01

    In order to elucidate the physiological significance of autonomic neuropathy in juvenile diabetics, cardiovascular, hormonal and metabolic functions have been investigated in three groups of juvenile diabetics: One group had no signs of neuropathy, one group had presumably slight autonomic...... neuropathy (reduced beat-to-beat variation in heart rate during hyperventilation) and one group had clinically severe autonomic neuropathy, defined by presence of orthostatic hypotension. In all three experimental situations we found sympathetic dysfunction causing cardiovascular and/or hormonal...... maladjustments in patients with autonomic neuropathy. Regarding metabolic functions we found normal responses to graded exercise and insulin-induced hypoglycemia in patients with autonomic neuropathy in spite of blunted catecholamine responses, suggesting increased sensitivity of glycogen stores and adipose...

  18. Advanced stellar compass onboard autonomous orbit determination, preliminary performance.

    Science.gov (United States)

    Betto, Maurizio; Jørgensen, John L; Jørgensen, Peter S; Denver, Troelz

    2004-05-01

    Deep space exploration is in the agenda of the major space agencies worldwide; certainly the European Space Agency (SMART Program) and the American NASA (New Millennium Program) have set up programs to allow the development and the demonstration of technologies that can reduce the risks and the cost of deep space missions. From past experience, it appears that navigation is the Achilles heel of deep space missions. Performed on ground, this imposes considerable constraints on the entire system and limits operations. This makes it is very expensive to execute, especially when the mission lasts several years and, furthermore, it is not failure tolerant. Nevertheless, to date, ground navigation has been the only viable solution. The technology breakthrough of advanced star trackers, like the advanced stellar compass (ASC), might change this situation. Indeed, exploiting the capabilities of this instrument, the authors have devised a method to determine the orbit of a spacecraft autonomously, onboard, and without a priori knowledge of any kind. The solution is robust and fast. This paper presents the preliminary performance obtained during the ground testing in August 2002 at the Mauna Kea Observatories. The main goals were: (1) to assess the robustness of the method in solving autonomously, onboard, the position lost-in-space problem; (2) to assess the preliminary accuracy achievable with a single planet and a single observation; (3) to verify the autonomous navigation (AutoNav) module could be implemented into an ASC without degrading the attitude measurements; and (4) to identify the areas of development and consolidation. The results obtained are very encouraging.

  19. GigaTracker, the NA62 Beam Tracker

    CERN Document Server

    Velghe, Bob; Bonacini, Sandro; Ceccucci, Augusto; Degrange, Jordan; Kaplon, Jan; Kluge, Alexander; Mapelli, Alessandro; Morel, Michel; Noël, Jérôme; Noy, Matthew; Perktold, Lukas; Petagna, Paolo; Poltorak, Karolina; Riedler, Petra; Romagnoli, Giulia; Chiozzi, Stefano; Ramusino, Angelo Cotta; Fiorini, Massimiliano; Gianoli, Alberto; Petrucci, Ferruccio; Wahl, Heinrich; Arcidiacono, Roberta; Jarron, Pierre; Marchetto, Flavio; Gil, Eduardo Cortina; Nuessle, Georg; Szilasi, Nicolas

    2015-01-01

    The GigaTracker measures the momentum, the direction and the crossing time of all the NA62 secondary beam particles. It is composed of three hybrid silicon pixel stations and four achromatic magnets. All the stations have a rate capability above 750 MHz, a single hit time resolution better than 200 ps and a thickness less than 0.5 % of X = X 0 . The stations’ sensor is read out by ten custom TDCpix ASICs. An innovative microchannel cooling solution is used to keep the sensor temperature below 0 °C. The stations are operated in vacuum and are easily swappable

  20. GigaTracker, a Thin and Fast Silicon Pixels Tracker

    CERN Document Server

    Velghe, Bob; Bonacini, Sandro; Ceccucci, Augusto; Kaplon, Jan; Kluge, Alexander; Mapelli, Alessandro; Morel, Michel; Noël, Jérôme; Noy, Matthew; Perktold, Lukas; Petagna, Paolo; Poltorak, Karolina; Riedler, Petra; Romagnoli, Giulia; Chiozzi, Stefano; Cotta Ramusino, Angelo; Fiorini, Massimiliano; Gianoli, Alberto; Petrucci, Ferruccio; Wahl, Heinrich; Arcidiacono, Roberta; Jarron, Pierre; Marchetto, Flavio; Gil, Eduardo Cortina; Nuessle, Georg; Szilasi, Nicolas

    2014-01-01

    GigaTracker, the NA62’s upstream spectrometer, plays a key role in the kinematically constrained background suppression for the study of the K + ! p + n ̄ n decay. It is made of three independent stations, each of which is a six by three cm 2 hybrid silicon pixels detector. To meet the NA62 physics goals, GigaTracker has to address challenging requirements. The hit time resolution must be better than 200 ps while keeping the total thickness of the sensor to less than 0.5 mm silicon equivalent. The 200 μm thick sensor is divided into 18000 300 μm 300 μm pixels bump-bounded to ten independent read-out chips. The chips use an end-of-column architecture and rely on time-over- threshold discriminators. A station can handle a crossing rate of 750 MHz. Microchannel cooling technology will be used to cool the assembly. It allows us to keep the sensor close to 0 C with 130 μm of silicon in the beam area. The sensor and read-out chip performance were validated using a 45 pixel demonstrator with a laser test setu...

  1. OptoTracker project proposal

    OpenAIRE

    Celentano, A.

    2016-01-01

    The project OptoTracker aims to investigate a new approach to track charged particles in a scintillating material, by using the optical signal. Our idea is to reconstruct the trajectory of a charged particle by collecting the scintillation light emitted along the path with pixelized photo-detectors. This would permit to obtain an image of the track, similarly to what is done in a photographic camera. Full 3D reconstruction is performed by using both the charge distribution and the hit time in...

  2. Development of a digital mobile solar tracker

    OpenAIRE

    Baidar, Sunil; Kille, Natalie; Ortega, Ivan; Sinreich, Roman; Thomson, David; Hannigan, James; Volkamer, Rainer

    2016-01-01

    We have constructed and deployed a fast digital solar tracker aboard a moving ground-based platform. The tracker consists of two rotating mirrors, a lens, an imaging camera, and a motion compensation system that provides the Euler angles of the mobile platform in real time. The tracker can be simultaneously coupled to UV–Vis and Fourier transform infrared spectrometers, making it a versatile tool to measure the absorption of trace gases using solar incoming radiation. The in...

  3. Development of a digital mobile solar tracker

    OpenAIRE

    S. Baidar; N. Kille; I. Ortega; R. Sinreich; Thomson, D.; Hannigan, J.; R. Volkamer

    2015-01-01

    We have constructed and deployed a fast digital solar tracker aboard a moving ground-based platform. The tracker consists of two rotating mirrors, a lens, an imaging camera, and a motion compensation system that provides the Euler angles of the mobile platform in real time. The tracker can be simultaneously coupled to UV-Vis and FTIR spectrometers making it a versatile tool to measure the absorption of trace gases using solar incoming radi...

  4. The ATLAS semiconductor tracker (SCT)

    CERN Document Server

    Jackson, J N

    2005-01-01

    The ATLAS detector (CERN/LHCC/94-43 (1994)) is designed to study a wide range of physics at the CERN Large Hadron Collider (LHC) at luminosities up to 10**3**4 cm**-**2 s**-**1 with a bunch-crossing rate of 40 MHz. The Semiconductor Tracker (SCT) forms a key component of the Inner Detector (vol. 1, ATLAS TDR 4, CERN/LHCC 97-16 (1997); vol. 2, ATLAS TDR 5, CERN/LHCC 97-17 (1997)) which is situated inside a 2 T solenoid field. The ATLAS Semiconductor Tracker (SCT) utilises 4088 silicon modules with binary readout mounted on carbon fibre composite structures arranged in the forms of barrels in the central region and discs in the forward region. The construction of the SCT is now well advanced. The design of the SCT modules, services and support structures will be briefly outlined. A description of the various stages in the construction process will be presented with examples of the performance achieved and the main difficulties encountered. Finally, the current status of the construction is reviewed.

  5. Teaching optical phenomena with Tracker

    Science.gov (United States)

    Rodrigues, M.; Simeão Carvalho, P.

    2014-11-01

    Since the invention and dissemination of domestic laser pointers, observing optical phenomena is a relatively easy task. Any student can buy a laser and experience at home, in a qualitative way, the reflection, refraction and even diffraction phenomena of light. However, quantitative experiments need instruments of high precision that have a relatively complex setup. Fortunately, nowadays it is possible to analyse optical phenomena in a simple and quantitative way using the freeware video analysis software ‘Tracker’. In this paper, we show the advantages of video-based experimental activities for teaching concepts in optics. We intend to show: (a) how easy the study of such phenomena can be, even at home, because only simple materials are needed, and Tracker provides the necessary measuring instruments; and (b) how we can use Tracker to improve students’ understanding of some optical concepts. We give examples using video modelling to study the laws of reflection, Snell’s laws, focal distances in lenses and mirrors, and diffraction phenomena, which we hope will motivate teachers to implement it in their own classes and schools.

  6. Oil Price Trackers Inspired by Immune Memory

    CERN Document Server

    Wilson, WIlliam; Aickelin, Uwe

    2010-01-01

    We outline initial concepts for an immune inspired algorithm to evaluate and predict oil price time series data. The proposed solution evolves a short term pool of trackers dynamically, with each member attempting to map trends and anticipate future price movements. Successful trackers feed into a long term memory pool that can generalise across repeating trend patterns. The resulting sequence of trackers, ordered in time, can be used as a forecasting tool. Examination of the pool of evolving trackers also provides valuable insight into the properties of the crude oil market.

  7. A Novel Approach for Star Extraction from Star Image

    Institute of Scientific and Technical Information of China (English)

    ZHENGSheng; LIUJian; TIANJinwen; YANGRuijuan

    2005-01-01

    Star acquisition is one of the most timeconsuming routines in star tracker operation. One star Point spread function (PSF) forms a near Gaussian distribution in the star image, the star image can be regarded as 2-D intensity surface, and every pixel is the sampled point. The star cluster grouping is to find the highes tintensity pixel among the PSFs and collect the adjacent pixels and group them. The possible highest intensity pixels are the maximum extremum points of the 2-D intensity surface. To efficiently extract star from the star image, a novel star acquisition approach, which uses the simplified least squares support vector machines regression algorithm to find the optimal intensity surface function and predictthe maximum extremum points, is proposed. Comput erexperiments are carried out for the simulated star images.The experimental results demonstrate that the proposed method has a lot of advantages, including the high efficiency and good robustness over a wide range of sensor noise.

  8. 无热化大相对孔径星敏感器光学系统设计%Optical System Design of Light Star Tracker with Low F-number

    Institute of Scientific and Technical Information of China (English)

    汤天瑾

    2011-01-01

    提出了一种大相时孔径轻小型光学系统的设计方案,给出了设计方案及热分析结果.光学系统工作谱段500~800nm,视场角9°,相对孔径1/1.2,光学系统设计结果良好,弥散斑直径在两个像元尺寸之内,能够满足光学系统对能量集中度和弥散斑的要求.基于光学热补偿理论对光学系统进行了无热化分析和消热设计.通过分析不同温度下的传递函数和能量集中度曲线,可以看出在-10℃~40℃温度范围内系统性能稳定,基本实现无热化.%The Paper presents an optical system design of light CCD star sensor with low F-number, and atermalization is also done based on the compensation theory of thermal dispersion,giving the design and thermo-optical analysis results. The lens system is composed of seven lens which has an F-number of F/1.2, a field of view of 9 degrees, and a working wavelength range of 500~800nm.The geometric spot dispersed in two pixels at its focal surface, which can satisfied the requirement of the encircled energy and spot dispersion. The encircled energy and modulation transfer function of the lens at different temperatures are given as examples , It shows that the athermal optical system can work steadily within the temperature range of ~10℃~40℃.

  9. Silicon photomultipliers for scintillating trackers

    Energy Technology Data Exchange (ETDEWEB)

    Rabaioli, S., E-mail: simone.rabaioli@gmail.com [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); Berra, A.; Bolognini, D. [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); INFN sezione di Milano Bicocca (Italy); Bonvicini, V. [INFN sezione di Trieste (Italy); Bosisio, L. [Universita degli Studi di Trieste and INFN sezione di Trieste (Italy); Ciano, S.; Iugovaz, D. [INFN sezione di Trieste (Italy); Lietti, D. [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); INFN sezione di Milano Bicocca (Italy); Penzo, A. [INFN sezione di Trieste (Italy); Prest, M. [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); INFN sezione di Milano Bicocca (Italy); Rashevskaya, I.; Reia, S. [INFN sezione di Trieste (Italy); Stoppani, L. [Universita degli Studi dell' Insubria, Via Valleggio, 11 - 22100 Como (Italy); Vallazza, E. [INFN sezione di Trieste (Italy)

    2012-12-11

    In recent years, silicon photomultipliers (SiPMs) have been proposed as a new kind of readout device for scintillating detectors in many experiments. A SiPM consists of a matrix of parallel-connected pixels, which are independent photon counters working in Geiger mode with very high gain ({approx}10{sup 6}). This contribution presents the use of an array of eight SiPMs (manufactured by FBK-irst) for the readout of a scintillating bar tracker (a small size prototype of the Electron Muon Ranger detector for the MICE experiment). The performances of the SiPMs in terms of signal to noise ratio, efficiency and time resolution will be compared to the ones of a multi-anode photomultiplier tube (MAPMT) connected to the same bars. Both the SiPMs and the MAPMT are interfaced to a VME system through a 64 channel MAROC ASIC.

  10. Silicon photomultipliers for scintillating trackers

    Science.gov (United States)

    Rabaioli, S.; Berra, A.; Bolognini, D.; Bonvicini, V.; Bosisio, L.; Ciano, S.; Iugovaz, D.; Lietti, D.; Penzo, A.; Prest, M.; Rashevskaya, I.; Reia, S.; Stoppani, L.; Vallazza, E.

    2012-12-01

    In recent years, silicon photomultipliers (SiPMs) have been proposed as a new kind of readout device for scintillating detectors in many experiments. A SiPM consists of a matrix of parallel-connected pixels, which are independent photon counters working in Geiger mode with very high gain (∼106). This contribution presents the use of an array of eight SiPMs (manufactured by FBK-irst) for the readout of a scintillating bar tracker (a small size prototype of the Electron Muon Ranger detector for the MICE experiment). The performances of the SiPMs in terms of signal to noise ratio, efficiency and time resolution will be compared to the ones of a multi-anode photomultiplier tube (MAPMT) connected to the same bars. Both the SiPMs and the MAPMT are interfaced to a VME system through a 64 channel MAROC ASIC.

  11. OptoTracker project proposal

    CERN Document Server

    Celentano, A

    2016-01-01

    The project OptoTracker aims to investigate a new approach to track charged particles in a scintillating material, by using the optical signal. Our idea is to reconstruct the trajectory of a charged particle by collecting the scintillation light emitted along the path with pixelized photo-detectors. This would permit to obtain an image of the track, similarly to what is done in a photographic camera. Full 3D reconstruction is performed by using both the charge distribution and the hit time information folded in a sophisticated reconstruction algorithm. This solution, compared to "traditional" tracking methods, exploits the fastest information carrier within a material: the light. Therefore, an optical tracking detector would be intrinsically capable of sustaining a very high interaction rate. Moreover, the intrinsic resolution would not be limited by carriers diffusion, as happens in charge-transport based detectors. This new technology could have a very large impact both on beam experiments, thanks to the po...

  12. Ruby on Rails Issue Tracker

    Science.gov (United States)

    Rodriguez, Juan Jared

    2014-01-01

    The purpose of this report is to detail the tasks accomplished as a NASA NIFS intern for the summer 2014 session. This internship opportunity is to develop an issue tracker Ruby on Rails web application to improve the communication of developmental anomalies between the Support Software Computer Software Configuration Item (CSCI) teams, System Build and Information Architecture. As many may know software development is an arduous, time consuming, collaborative effort. It involves nearly as much work designing, planning, collaborating, discussing, and resolving issues as effort expended in actual development. This internship opportunity was put in place to help alleviate the amount of time spent discussing issues such as bugs, missing tests, new requirements, and usability concerns that arise during development and throughout the life cycle of software applications once in production.

  13. CMS Tracker Integration: monitoring the process quality

    International Nuclear Information System (INIS)

    The CMS experiment at LHC features the largest Silicon Strip Tracker (SST) ever built. This detector is composed of about 15000 modules, thus the potential problems of the system comes from its complexity. This article covers the tests performed during the tracker integration, describing their motivations in terms of process quality assurance

  14. The Chesapeake Laser Tracker in Industrial Metrology

    Energy Technology Data Exchange (ETDEWEB)

    Ruland, Robert E.; /SLAC

    2005-08-16

    In the summer of 1992, the survey and alignment team at the Stanford Linear Accelerator Center acquired a CMS3000 laser tracker manufactured by Chesapeake Laser Systems in Lanham, Maryland. This paper gives a description of the principles of operation and calibration of the tracker. Several applications are explained and the results shared.

  15. Adaptive Visual Face Tracking for an Autonomous Robot

    NARCIS (Netherlands)

    van Hoof, Herke; van der Zant, Tijn; Wiering, Marco

    2011-01-01

    Perception is an essential ability for autonomous robots in non-standardized conditions. However, the appearance of objects can change between different conditions. A system visually tracking a target based on its appearance could lose its target in those cases. A tracker learning the appearance of

  16. The LHCb Upstream Tracker Project

    CERN Document Server

    Steinkamp, Olaf

    2015-01-01

    The LHCb detector performs searches for New Physics in CP-violating observables and rare heavy-quark decays at the LHC. A comprehensive upgrade is planned for the long shutdown of the LHC in 2018/19. A goal of this upgrade is to abolish hardware triggers and read out the full detector at 40 MHz. This requires to replace the existing TT station upstream of the LHCb magnet by a new silicon micro-strip detector, the Upstream Tracker (UT). The UT will have a new front-end chip compatible with 40 MHz readout, silicon sensors with improved radiation hardness, finer readout granularity, and improved acceptance coverage at small polar angles. The outer region of each detection layer will be covered by p-in-n sensors with 10 cm long strips and a pitch of about 180 mum, while n-in-p sensors with half the pitch and strip length will be employed in the regions of highest particle density close to the beam pipe. The innermost sensors will have a circular cutout to optimize the forward acceptance. The front-end chip is bei...

  17. ATLAS Fast Tracker Simulation Challenges

    CERN Document Server

    Adelman, Jahred; The ATLAS collaboration; Borodin, Mikhail; Chakraborty, Dhiman; García Navarro, José Enrique; Golubkov, Dmitry; Kama, Sami; Panitkin, Sergey; Smirnov, Yuri; Stewart, Graeme; Tompkins, Lauren; Vaniachine, Alexandre; Volpi, Guido

    2015-01-01

    To deal with Big Data flood from the ATLAS detector most events have to be rejected in the trigger system. the trigger rejection is complicated by the presence of a large number of minimum-bias events – the pileup. To limit pileup effects in the high luminosity environment of the LHC Run-2, ATLAS relies on full tracking provided by the Fast TracKer (FTK) implemented with custom electronics. The FTK data processing pipeline has to be simulated in preparation for LHC upgrades to support electronics design and develop trigger strategies at high luminosity. The simulation of the FTK - a highly parallelized system - has inherent performance bottlenecks on general-purpose CPUs. To take advantage of the Grid Computing power, the FTK simulation is integrated with Monte Carlo simulations at the Production System level above the ATLAS workload management system PanDA. We report on ATLAS experience with FTK simulations on the Grid and next steps for accommodating the growing requirements for resources during the LHC R...

  18. Upgrade of the CMS Tracker

    CERN Document Server

    Klein, Katja

    2013-01-01

    The performance of the Tracker of the CMS experiment, comprising of a pixel and a strip detector, has so far been excellent, as reflected in the wealth of beautiful physics results from CMS. However, the foreseen increases of both the instantaneous and the integrated luminosity by the LHC during the next ten years will necessitate a stepwise upgrade of the CMS tracking detector. \\\\ In the extended end-of-year shutdown 2016/17 the pixel detector will be exchanged. The new device is designed for an instantaneous luminosity of $2\\cdot 10^{34}$\\,cm$^{-2}$s$^{-1}$ and an integrated luminosity of 500\\,fb$^{-1}$. The number of layers will be increased from three to four in the barrel part and from two to three in the end caps, thus providing four-hit coverage over the full pseudorapidity range. A smaller beampipe allows the reduction of the radius of the innermost layer, improving the tracking performance. Further improvements include a new readout chip, reduction of material, and the installation of more effi...

  19. ATLAS Silicon Microstrip Tracker Operation

    CERN Document Server

    Berglund, E; The ATLAS collaboration

    2009-01-01

    The ATLAS experiment at the CERN Large Hadron Collider (LHC) has started taking data last autumn with the inauguration of the LHC. The SemiConductor Tracker (SCT) is the key precision tracking device in ATLAS, made up from silicon micro-strip detectors processed in the planar p-in-n technology. The completed SCT has been installed inside the ATLAS experimental hall. Since then the detector was operated for many months under realistic conditions. Calibration data has been taken and analyzed to determine the noise performance of the system. In addition, extensive commissioning with cosmic ray events has been performed both with and without magnetic field. The cosmic muon data has been used to align the detector, to check the timing of the front-end electronics as well as to measure the hit efficiency of modules. The sensor behavior in magnetic field was studied by measurements of the Lorentz angle. For the initial running with unfocused LHC beam operation with undepleted sensors is foreseen. Efficiency and nois...

  20. The D0 silicon microstrip tracker

    CERN Document Server

    Quinn, B

    2003-01-01

    The D0 collaboration has completed building a 793,000 channel silicon microstrip tracker for the D0 upgrade. The tracker consists of 768 ladder and wedge assemblies including both single- and double-sided detectors. Detector readout utilizes the SVX-IIE radiation hard chip with on-chip digitization and sparsification. A brief review of the detector design is presented along with results from the assembly and testing processes. The operation of the full readout chain and the performance of the silicon tracker are described. Finally, lessons for future production of large scale tracking systems are discussed.

  1. Power Studies for the CMS Pixel Tracker

    International Nuclear Information System (INIS)

    The Electronic Systems Engineering Department of the Computing Division at the Fermi National Accelerator Laboratory is carrying out R and D investigations for the upgrade of the power distribution system of the Compact Muon Solenoid (CMS) Pixel Tracker at the Large Hadron Collider (LHC). Among the goals of this effort is that of analyzing the feasibility of alternative powering schemes for the forward tracker, including DC to DC voltage conversion techniques using commercially available and custom switching regulator circuits. Tests of these approaches are performed using the PSI46 pixel readout chip currently in use at the CMS Tracker. Performance measures of the detector electronics will include pixel noise and threshold dispersion results. Issues related to susceptibility to switching noise will be studied and presented. In this paper, we describe the current power distribution network of the CMS Tracker, study the implications of the proposed upgrade with DC-DC converters powering scheme and perform noise susceptibility analysis.

  2. Power distribution studies for CMS forward tracker

    International Nuclear Information System (INIS)

    The Electronic Systems Engineering Department of the Computing Division at the Fermi National Accelerator Laboratory is carrying out R and D investigations for the upgrade of the power distribution system of the Compact Muon Solenoid (CMS) Pixel Tracker at the Large Hadron Collider (LHC). Among the goals of this effort is that of analyzing the feasibility of alternative powering schemes for the forward tracker, including DC to DC voltage conversion techniques using commercially available and custom switching regulator circuits. Tests of these approaches are performed using the PSI46 pixel readout chip currently in use at the CMS Tracker. Performance measures of the detector electronics will include pixel noise and threshold dispersion results. Issues related to susceptibility to switching noise will be studied and presented. In this paper, we describe the current power distribution network of the CMS Tracker, study the implications of the proposed upgrade with DC-DC converters powering scheme and perform noise susceptibility analysis.

  3. CarbonTracker CT2007B release

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CarbonTracker is an open product of the NOAA Earth System Research Laboratory using data from the Global Monitoring Division greenhouse gas observational network...

  4. Last ATLAS transition radiation tracker module installed

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    The ATLAS transition radiation tracker consists of 96 modules and will join the pixel detector and silicon tracker at the heart of the experiment to map the trajectories of particles and identify electrons produced when proton beams collide. In the last image the team responsible for assembly are shown from left to right: Kirill Egorov (Petersburg Nuclear Physics Institute), Pauline Gagnon (Indiana University), Ben Legeyt (University of Pennsylvania), Chuck Long (Hampton University), John Callahan (Indiana University) and Alex High (University of Pennsylvania).

  5. Work on the ATLAS semiconductor tracker barrel

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    Precision work is performed on the semiconductor tracker barrel of the ATLAS experiment. All work on these delicate components must be performed in a clean room so that impurities in the air, such as dust, do not contaminate the detector. The semiconductor tracker will be mounted in the barrel close to the heart of the ATLAS experiment to detect the path of particles produced in proton-proton collisions.

  6. Search for tracker potentials in quintessence theory

    Science.gov (United States)

    Johri, Vinod B.

    2002-12-01

    We report a significant finding in quintessence theory that scalar fields with tracker potentials have a model-independent scaling behaviour in the expanding universe. So far, widely discussed exponential, power law or hyperbolic potentials can simply mimic the tracking behaviour over a limited range of redshift. A new version of the tracker field theory is proposed and it is shown that in the small redshift range where the variation of the tracking parameter ɛ may be taken to be negligible, the differential equation of generic potentials leads to hyperbolic sine and hyperbolic cosine potentials which may approximate a tracker field in the present-day universe. We have plotted the variation of the tracker potential and the equation of state of the tracker field as a function of the redshift z for the model-independent relation derived from tracker field theory; we have also plotted the variation of V(Φ) in terms of the scalar field Φ for the chosen hyperbolic cosine function and have compared it with the curves obtained by the reconstruction of V(Φ) from real observational data from the supernovae.

  7. Angular-Rate Estimation using Star Tracker Measurements

    Science.gov (United States)

    Azor, R.; Bar-Itzhack, Itzhack Y.; Deutschmann, Julie K.; Harman, Richard R.

    1999-01-01

    This paper presents algorithms for estimating the angular-rate vector of satellites using quaternion measurements. Two approaches are compared, one that uses differentiated quaternion measurements to yield coarse rate measurements which are then fed into two different estimators. In the other approach the raw quaternion measurements themselves are fed directly into the two estimators. The two estimators rely on the ability to decompose the non-linear rate dependent part of the rotational dynamics equation of a rigid body into a product of an angular-rate dependent matrix and the angular-rate vector itself. This decomposition, which is not unique, enables the treatment of the nonlinear spacecraft dynamics model as a linear one and, consequently, the application of a Pseudo-Linear Kalman Filter (PSELIKA). It also enables the application of a special Kalman filter which is based on the use of the solution of the State Dependent Algebraic Riccati Equation (SDARE) in order to compute the Kalman gain matrix and thus eliminates the need to propagate and update the filter covariance matrix. The replacement of the elaborate rotational dynamics by a simple first order Markov model is also examined. In this paper a special consideration is given to the problem of delayed quaternion measurements. Two solutions to this problem are suggested and tested. Real Rossi X-Ray Timing Explorer (RXTE) data is used to test these algorithms, and results of these tests are presented.

  8. The silicon drift vertex detector for the STAR experiment at RHIC

    CERN Document Server

    Pandey, S U; Beuttenmüller, Rolf H; Caines, H; Chen, W; Dimassimo, D; Dyke, H; Elliot, D; Eremin, V; Grau, M; Hoffmann, G W; Humanic, T; Ilyashenko, Yu S; Kotov, I; Kraner, H W; Kuczewski, P; Leonhardt, B; Li, Z; Liaw, C J; Lo Curto, G; Middelkamp, P; Minor, R; Munhoz, M; Ott, G; Pruneau, C A; Rykov, V L; Schambach, J; Sedlmeir, J; Soja, B; Sugarbaker, E R; Takahashi, J; Wilson, K; Wilson, R

    2002-01-01

    The current status of the STAR Silicon Vertex Tracker (SVT) is presented. The performance of the Silicon Drift Detectors (SDD) is discussed. Results for a recent 15 layer SDD tracker which prototypes all components of the SVT are presented. The enhanced physics capabilities of the STAR detector due to the addition of the SVT are addressed.

  9. Autonomous Search

    CERN Document Server

    Hamadi, Youssef; Saubion, Frédéric

    2012-01-01

    Decades of innovations in combinatorial problem solving have produced better and more complex algorithms. These new methods are better since they can solve larger problems and address new application domains. They are also more complex which means that they are hard to reproduce and often harder to fine-tune to the peculiarities of a given problem. This last point has created a paradox where efficient tools are out of reach of practitioners. Autonomous search (AS) represents a new research field defined to precisely address the above challenge. Its major strength and originality consist in the

  10. Measurements of strangeness production in the STAR experiment at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, W.K. [Wayne State Univ., Detroit, MI (United States)

    1995-07-15

    Simulations of the ability of the STAR (Solenoidal Tracker at RHIC) detector to measure strangeness production in central Au+Au collisions at RHIC are presented. Emphasis is placed on the reconstruction of short lived particles using a high resolution inner tracker. The prospects for performing neutral kaon interferometry are discussed. Simulation results for measurements of strange and multi-strange baryons are presented.

  11. Pure Autonomic Failure

    Science.gov (United States)

    ... Drugs GARD Information Navigator FAQs About Rare Diseases Pure autonomic failure Title Other Names: Bradbury Eggleston syndrome; ... Categories: Nervous System Diseases ; RDCRN Summary Summary Listen Pure autonomic failure is characterized by generalized autonomic failure ...

  12. Search for Tracker Potentials in Quintessence Theory

    CERN Document Server

    Johri, V B

    2002-01-01

    We report a significant finding in Quintessence theory that the the scalar fields with tracker potentials have a model-independent scaling behaviour in the expanding universe. So far widely discussed exponential,power law or hyperbolic potentials can simply mimic the tracking behaviour over a limited range of redshift. In the small redshift range where the variation of the tracking parameter $\\epsilon$ may be taken to be negligible, the differential equation of generic potentials leads to hyperbolic sine and hyperbolic cosine potentials which may approximate tracker field in the present day universe. We have plotted the variation of tracker potential and the equation of state of the tracker field as function of the redshift $z$ for the model-independent relation derived from tracker field theory; we have also plotted the variation of $V(\\Phi)$ in terms of the scalar field $\\Phi$ for the chosen hyperbolic cosine function and have compared with the curves obtained by reconstruction of $V(\\phi)$ from the real ob...

  13. CMS tracker slides into centre stage

    CERN Multimedia

    2006-01-01

    As preparations for the magnet test and cosmic challenge get underway, a prototype tracker has been carefully inserted into the centre of CMS. The tracker, in its special platform, is slowly inserted into the centre of CMS. The CMS prototype tracker to be used for the magnet test and cosmic challenge coming up this summer has the same dimensions -2.5 m in diameter and 6 m in length- as the real one and tooling exactly like it. However, the support tube is only about 1% equipped, with 2 m2 of silicon detectors installed out of the total 200 m2. This is already more than any LEP experiment ever used and indicates the great care needed to be taken by engineers and technicians as these fragile detectors were installed and transported to Point 5. Sixteen thousand silicon detectors with a total of about 10 million strips will make up the full tracker. So far, 140 modules with about 100 000 strips have been implanted into the prototype tracker. These silicon strips will provide precision tracking for cosmic muon...

  14. Star Pattern Recognition for Attitude Determination using Genetic Algorithms

    OpenAIRE

    Paladugu, Lalitha; Williams, Brian,; Schoen, Marco

    2003-01-01

    This paper presents a study using Genetic Algorithms (GA) to solve the star pattern recognition problem associated with star tracker attitude determination systems. Characteristics of the stars that are visible within the Field of View (FOV) of an imager are defined with regard to relative distances and angles. The proposed GA minimizes the discrepancy between the characteristics of the stars inside the actual FOV and a candidate FOV selected from the star map in order to determine the inerti...

  15. Diabetic autonomic neuropathy.

    Science.gov (United States)

    Freeman, Roy

    2014-01-01

    Diabetes mellitus is the commonest cause of an autonomic neuropathy in the developed world. Diabetic autonomic neuropathy causes a constellation of symptoms and signs affecting cardiovascular, urogenital, gastrointestinal, pupillomotor, thermoregulatory, and sudomotor systems. Several discrete syndromes associated with diabetes cause autonomic dysfunction. The most prevalent of these are: generalized diabetic autonomic neuropathy, autonomic neuropathy associated with the prediabetic state, treatment-induced painful and autonomic neuropathy, and transient hypoglycemia-associated autonomic neuropathy. These autonomic manifestations of diabetes are responsible for the most troublesome and disabling features of diabetic peripheral neuropathy and result in a significant proportion of the mortality and morbidity associated with the disease.

  16. The Spacelab IPS Star Simulator

    Science.gov (United States)

    Wessling, Francis C., III

    1993-01-01

    The cost of doing business in space is very high. If errors occur while in orbit the costs grow and desired scientific data may be corrupted or even lost. The Spacelab Instrument Pointing System (IPS) Star Simulator is a unique test bed that allows star trackers to interface with simulated stars in a laboratory before going into orbit. This hardware-in-the loop testing of equipment on earth increases the probability of success while in space. The IPS Star Simulator provides three fields of view 2.55 x 2.55 degrees each for input into star trackers. The fields of view are produced on three separate monitors. Each monitor has 4096 x 4096 addressable points and can display 50 stars (pixels) maximum at a given time. The pixel refresh rate is 1000 Hz. The spectral output is approximately 550 nm. The available relative visual magnitude range is 2 to 8 visual magnitudes. The star size is less than 100 arc seconds. The minimum star movement is less than 5 arc seconds and the relative position accuracy is approximately 40 arc seconds. The purpose of this paper is to describe the LPS Star Simulator design and to provide an operational scenario so others may gain from the approach and possible use of the system.

  17. Price Trackers Inspired by Immune Memory

    CERN Document Server

    Wilson, William; Aickelin, Uwe

    2010-01-01

    In this paper we outline initial concepts for an immune inspired algorithm to evaluate price time series data. The proposed solution evolves a short term pool of trackers dynamically through a process of proliferation and mutation, with each member attempting to map to trends in price movements. Successful trackers feed into a long term memory pool that can generalise across repeating trend patterns. Tests are performed to examine the algorithm's ability to successfully identify trends in a small data set. The influence of the long term memory pool is then examined. We find the algorithm is able to identify price trends presented successfully and efficiently.

  18. Preliminary studies of a chromaticity tracker

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Cheng-Yang; /Fermilab

    2006-03-01

    A chromaticity tracker based on a method by D. McGinnis is proposed. This method starts with the slow modulation of the accelerating RF which causes the beam to respond to it. This beam modulation can be detected transversely with a Schottky pickup which after phase demodulation, the chromaticity can be calculated from it. However, to perform phase demodulation, the carrier frequency which is the betatron tune needs to be identified. The identification of the carrier frequency falls naturally onto the phase locked loop tune tracker which when locked to the betatron tune outputs this value in real time.

  19. The CMS silicon strip tracker modules production

    CERN Document Server

    Giorgi, M

    2006-01-01

    To complete the construction of the CMS silicon strip tracker, about 16,000 silicon microstrip detector modules will be required. In order to guarantee the uniform quality of the produced modules and to be able to match the deadlines requested by the CMS collaboration, a semi-industrialized organization has been developed, and the different components are being presented here.

  20. Sun Tracker Operates a Year Between Calibrations

    Science.gov (United States)

    Berdahl, C. M.

    1984-01-01

    Low-cost modification of Sun tracker automatically compensates equation of time and seasonal variations in declination of Sun. Output of Scotch Yoke drive mechanism adjusted through proper sizing of crank, yoke and other components and through choice of gear ratios to approximate seasonal northand south motion of Sun. Used for industrial solar-energy monitoring and in remote meteorological stations.

  1. The D0 Silicon Microstrip Tracker

    CERN Document Server

    Ahmed, S N; Aoki, M; Åsman, B; Austin, S; Bagby, L; Barberis, E; Baringer, P; Bean, A; Bischoff, A; Blekman, F; Bolton, T A; Boswell, C; Bowden, M; Browning, F; Buchholz, D; Burdin, S; Butler, D; Cease, H; Choi, S; Clark, A R; Clutter, J; Cooper, A; Cooper, W E; Corcoran, M; de Jong, S J; Demarteau, M; Demina, R; Desai, S; Derylo, G; Ellison, J; Ermolov, P; Fagan, J; Fast, J; Filthaut, F; Foglesong, J; Fox, H; Galea, C F; Gardner, J; Genik, R J; Gerber, C E; Gershtein, Y; Gounder, K; Grinstein, S; Gu, W; Gutierrez, P; Haggerty, H; Hall, R E; Hagopian, S; Hance, R; Harder, K; Heger, P; Heinson, A P; Heintz, U; Hesketh, G; Hover, D; Howell, J; Hrycyk, M; Iashvili, I; Johnson, M; Jöstlein, H; Juste, A; Kahl, W; Kajfasz, E; Karmanov, D; Kesisoglou, S; Khanov, A; King, J; Kleinfelder, S; Kowalski, J; Krempetz, K; Kubantsev, M; Kulik, Y; Landsberg, G; Leflat, A; Lehner, F; Lipton, R; Mao, H S; Martin, M; Mateski, J; Matulik, M; McKenna, M; Melnitchouk, A; Merkin, M; Mihalcea, D; Milgrome, O; Montgomery, H E; Moua, S; Naumann, N A; Nomerotski, A; Olis, D; O'Neil, D C; Garzón, G J Otero y; Parua, N; Pawlak, J; Petteni, M; Quinn, B; Rapidis, P A; Ratzmann, P; Rizatdinova, F; Roco, M; Rucinski, R; Rykalin, V; Schellman, H; Schmitt, W; Sellberg, G; Serritella, C; Shabalina, E; Sidwell, R A; Simak, V; Smith, E; Squires, B; Stanton, N R; Steinbrück, G; Strandberg, J; Strandberg, S; Strauss, M; Stredde, S; Toukhtarov, A; Tripathi, S M; Trippe, T G; Tsybychev, D; Utes, M; van Gemmeren, P; Vaz, M; Weber, M; Wijngaarden, D A; Wish, J; Womersley, J; Yarema, R; Ye, Z; Zieminski, A; Zimmerman, T; Zverev, E G

    2010-01-01

    This paper describes the mechanical design, the readout chain, the production, testing and the installation of the Silicon Microstrip Tracker of the D0 experiment at the Fermilab Tevatron collider. In addition, description of the performance of the detector during the experiment data collection between 2001 and 2010 is provided.

  2. Developments for the TOF Straw Tracker

    Energy Technology Data Exchange (ETDEWEB)

    Ucar, A.

    2006-07-01

    COSY-TOF is a very large acceptance spectrometer for charged particles using precise information on track geometry and time of flight of reaction products. It is an external detector system at the Cooler Synchrotron and storage ring COSY in Juelich. In order to improve the performance of the COSY-TOF, a new tracking detector ''Straw Tracker'' is being constructed which combines very low mass, operation in vacuum, very good resolution, high sampling density and very high acceptance. A comparison of pp{yields}d{pi}{sup +} data and a simulation using the straw tracker with geometry alone indicates big improvements with the new tracker. In order to investigate the straw tracker properties a small tracking hodoscope ''cosmic ray test facility'' was constructed in advance. It is made of two crossed hodoscopes consisting of 128 straw tubes arranged in 4 double planes. For the first time Juelich straws have been used for 3 dimensional reconstruction of cosmic ray tracks. In this illuminating field the space dependent response of scintillators and a straw tube were studied. (orig.)

  3. UK semiconductor tracker parts head for CERN

    CERN Multimedia

    Holland, Colin

    2005-01-01

    The last of the 4 barrels that make up the central part of the Semiconductor Tracker (SCT), the heart of the biggest physics collaboration in the world have left Oxford for its new home at the European Particle Physics Laboratory, CERN, near Geneva

  4. Conceptual design report for the Solenoidal Tracker at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    The STAR Collaboration

    1992-06-15

    The Solenoidal Tracker At RHIC (STAR) will search for signatures of quark-gluon plasma (QGP) formation and investigate the behavior of strongly interacting matter at high energy density. The emphasis win be the correlation of many observables on an event-by-event basis. In the absence of definitive signatures for the QGP, it is imperative that such correlations be used to identify special events and possible signatures. This requires a flexible detection system that can simultaneously measure many experimental observables. The physics goals dictate the design of star and it`s experiment. To meet the design criteria, tracking, momentum analysis, and particle identification of most of the charged particles at midrapidity are necessary. The tracking must operate in conditions at higher than the expected maximum charged particle multiplicities for central Au + Au collisions. Particle identification of pions/kaons for p < 0.7 GeV/c and kaons/protons for p < 1 GeV/c, as well as measurement of decay particles and reconstruction of secondary vertices will be possible. A two-track resolution of 2 cm at 2 m radial distance from, the interaction is expected. Momentum resolution of {Delta}p/p {approximately} 0.02 at p = 0.1 GeV/c is required to accomplish the physics, and,{Delta}p/p of several percent at p = 10 GeV/c is sufficient to accurately measure the rapidly failing spectra at high Pt and particles from mini-jets and jets.

  5. LEO AUTONOMOUS NAVIGATION BASED ON IMAGE MOTION

    Institute of Scientific and Technical Information of China (English)

    DUANFang; LIUJian-ye; YUFeng

    2005-01-01

    A method of LEO autonomous navigation is presented based on the nonlinear satellite velocity relative to the earth. The velocity is detected by a high-speed camera, with the attitude information detected by a star sensor. Compared with traditional autonomous navigation by landmark identification, the satellite velocity relarive to the earth is obtained by correlativity analysis of images. It does not need to recognize ground objects or views. Since it is not necessary to pre-store the database of ground marks, lots of memory space can be saved.The state and observation equations are constructed, and the filtering is processed by the Kalman filter. Simulation results show that the system has high autonomous navigation precision in LEO autonomous navigation.

  6. The research and development of the automatic solar power tracker

    Directory of Open Access Journals (Sweden)

    Li Yan Ping

    2016-01-01

    Full Text Available The article describes a kind of automatic tracker using solar power. It depends on two important parts which are servo system and adjusting mechanism system to keep the tracker operating normally. The article focuses on describing the characteristics and functions of two systems and the operating details of the automatic solar power tracker.

  7. OFFSET: Optical Fiber Folded Scintillating Extended Tracker

    International Nuclear Information System (INIS)

    The OFFSET collaboration aims at the development of a novel system for tracking charged particles, designed to achieve real-time imaging, large detection areas, and a high spatial resolution especially suitable for use in medical diagnostics. This paper presents the first prototype of this tracker, having a 20×20 cm2 sensitive area made by two crossed ribbons of 500μm square scintillating fibers. The track position information is extracted in real time using a reduced number of read-out channels to obtain very large detection area at moderate cost and complexity. The performance of the tracker was investigated using β sources, cosmic rays and a 62 MeV proton beam

  8. Target for optically activated seekers and trackers

    Science.gov (United States)

    Lakin, C. T.; Willett, N. F.

    1984-05-01

    This abstract discloses a target for optically activated seekers and trackers (TOAST) which provides for calibrated and variable target characteristics such as size, intensity, spatial position, color and interfering background. The TOAST has a first ilumination system providing a target light beam through an adjustable iris which controls image size. The target beam passes through a collimator lens which focuses the light at infinity. With the target beam focused at infinity, the motion of an elevation plate lengthens or shortens the distance from the collimator lens to a one motion mirror. The target beam is attenuated by a variable filter driven by a servo-motor, and a color selection process is provided by passing the beam through spectral filters. A background light beam with background imagery is provided to the beamsplitter mirror and mixed with the target image so as to simulate the target environment encountered by an operating optically activated seeker and tracker.

  9. CMS tracker towards the HL-LHC

    CERN Document Server

    Alunni Solestizi, Luisa

    2015-01-01

    In sight of the incoming new LHC era (High Luminosity - LHC), characterized by a jump forward in the precision boundary and in the event rate, all the CMS sub-detector are developing and studying innovative strategies of trigger, pattern recognition, event timing and so on. A crucial aspect will be the online event selection: a totally new paradigm is needed, given the huge amount of events. In this picture the most granular and innermost sub-detector, the tracker, will play a decisive role. The phase-2 tracker will be involved in the L1 Trigger and, taking advantage of both the Associative Memories and the FPGA, it can ensure a trigger decision in proper time and with satisfactory performances.

  10. Dynamic exit pupil trackers for autostereoscopic displays

    OpenAIRE

    Akşit, Kaan; Ölçer, Selim; Ürey, Hakan; Baghsiahi, Hadi; Surman, Phil; Willman, Eero; Selviah, David R.; Day, Sally

    2013-01-01

    Dynamic exit pupil trackers for autostereoscopic displays Kaan Akşit,1,* Hadi Baghsiahi,2 Phil Surman,3 Selim Ӧlçer,1 Eero Willman,2 David R. Selviah,2 Sally Day, 2 and Hakan Urey1 1Koç University, Department of Electrical Engineering Istanbul, 34450, Turkey 2University College London, UCL, Department of Electronic & Electrical Engineering, WC1E 7JE, London, UK 3De Montfort University, Department of Computer Technology, Leicester, UK * Abstract: This...

  11. Search for Tracker Potentials in Quintessence Theory

    OpenAIRE

    Johri, Vinod B.

    2001-01-01

    We report a significant finding in Quintessence theory that the the scalar fields with tracker potentials have a model-independent scaling behaviour in the expanding universe. So far widely discussed exponential,power law or hyperbolic potentials can simply mimic the tracking behaviour over a limited range of redshift. In the small redshift range where the variation of the tracking parameter $\\epsilon$ may be taken to be negligible, the differential equation of generic potentials leads to hyp...

  12. Radiation monitoring system for LHCb inner tracker

    International Nuclear Information System (INIS)

    Performance requirements to and the design of a radiation monitoring system (RMS) for the LHCb inner Tracker (CERN) have been presented. The physical principle of operation and some constructional details of metal foil detectors (MFDs) developed at the Institute for Nuclear Research of the National Academy of Sciences of Ukraine and used in the RMS manufacture have been described. The results of testing demonstrate that the parameters of the RMS correspond to the requirements of the LHCb experiment

  13. The CMS Tracker Detector Control System

    Energy Technology Data Exchange (ETDEWEB)

    Yousaf Shah, S. [University of California, Santa Barbara, CA (United States)], E-mail: yousaf.shah@cern.ch; Tsirou, Andromachi; Verdini, Piero Giorgio [CERN, Geneva (Switzerland); Hartmann, Frank [University of Karlsruhe, Karlsruhe (Germany); Masetti, Lorenzo [CERN, Geneva (Switzerland); Dirkes, Guido H. [University of Karlsruhe, Karlsruhe (Germany); Stringer, Robert [University of California, Riverside, CA (United States); Fahrer, Manuel [CERN, Geneva (Switzerland)

    2009-06-01

    The Compact Muon Solenoid DCS (CMS) Silicon Strip Tracker is by far the largest detector ever built in micro-strip technology. It has an active surface area of 198 m{sup 2} consisting of 15,148 silicon modules with 9,316,352 readout channels read via 75,376 Analog Pipeline Voltage (APV) front-end chips and a total of 24,244 sensors. The Detector Control System (DCS) for the Tracker is a distributed control system that operates {approx}2000 power supplies for the silicon modules and also monitors its environmental sensors. The DCS receives information from about 10{sup 3} environmental probes (temperature and humidity sensors) located inside the detector's volume and values from these probes are driven through the Programmable Logic Controllers (PLC) of the Detector Safety System (DSS). A total of 10{sup 5} parameters are read out from the dedicated chips in the front-end electronics of the detector via the data acquisition system, and a total of 10{sup 5} parameters are read from the power supply modules. All these parameters are monitored, evaluated and correlated with the detector layout; actions are taken under specific conditions. The hardware for DCS consists of 10 PCs and 10 PLC systems that are continuously running the necessary control and safety routines. The DCS is a fundamental tool for the Tracker operation and its safety.

  14. Magnet Test Setup of the CMS Tracker ready for installation

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    The pieces of the Tracker that will be operated in the forthcoming Magnet Test and Cosmic Challenge (MTCC) have been transported inside the dummy tracker support tube to the CMS experimental hall (Point 5, Cessy). The operation took place during the night of 12th May, covering the ~15km distance in about three hours. The transport was monitored for shocks, temperature and humidity with the help of the CERN TS-IC section. The Tracker setup comprises segments of the Tracker Inner Barrel (TIB), the Tracker Outer Barrel (TOB) and Tracker EndCaps (TEC) detectors. It represents roughly 1% of the final CMS Tracker. Installation into the solenoid is foreseen to take place on Wednesday 17th May.

  15. Autonomic Nervous System Disorders

    Science.gov (United States)

    Your autonomic nervous system is the part of your nervous system that controls involuntary actions, such as the beating of your heart ... breathing and swallowing Erectile dysfunction in men Autonomic nervous system disorders can occur alone or as the result ...

  16. Autoimmune Autonomic Ganglionopathy

    Science.gov (United States)

    ... Accessed 9/2/2015. Autoimmune Autonomic Ganglionopathy Summary. Dysautonomia International . http://www.dysautonomiainternational.org/page.php?ID= ... page Basic Information In Depth Information Basic Information Dysautonomia International offers an information page on Autoimmune autonomic ...

  17. [Trigeminal autonomic cephalgias].

    Science.gov (United States)

    Maximova, M Yu; Piradov, M A; Suanova, E T; Sineva, N A

    2015-01-01

    Review of literature on the trigeminal autonomic cephalgias are presented. Trigeminal autonomic cephalgias are primary headaches with phenotype consisting of trigeminal pain with autonomic sign including lacrimation, rhinorrhea and miosis. Discussed are issues of classification, pathogenesis, clinical picture, diagnosis, differential diagnosis and treatment of this headache. Special attention is paid to cluster headache, paroxysmal hemicrania, SUNCT syndrome, hemicrania continua.

  18. Robust visual tracking with dual spatio-temporal context trackers

    Science.gov (United States)

    Sun, Shiyan; Zhang, Hong; Yuan, Ding

    2015-12-01

    Visual tracking is a challenging problem in computer vision. Recent years, significant numbers of trackers have been proposed. Among these trackers, tracking with dense spatio-temporal context has been proved to be an efficient and accurate method. Other than trackers with online trained classifier that struggle to meet the requirement of real-time tracking task, a tracker with spatio-temporal context can run at hundreds of frames per second with Fast Fourier Transform (FFT). Nevertheless, the performance of the tracker with Spatio-temporal context relies heavily on the learning rate of the context, which restricts the robustness of the tracker. In this paper, we proposed a tracking method with dual spatio-temporal context trackers that hold different learning rate during tracking. The tracker with high learning rate could track the target smoothly when the appearance of target changes, while the tracker with low learning rate could percepts the occlusion occurring and continues to track when the target starts to emerge again. To find the target among the candidates from these two trackers, we adopt Normalized Correlation Coefficient (NCC) to evaluate the confidence of each sample. Experimental results show that the proposed algorithm performs robustly against several state-of-the-art tracking methods.

  19. Conceptual design report for the Solenoidal Tracker at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    1992-06-15

    The Solenoidal Tracker At RHIC (STAR) will search for signatures of quark-gluon plasma (QGP) formation and investigate the behavior of strongly interacting matter at high energy density. The emphasis win be the correlation of many observables on an event-by-event basis. In the absence of definitive signatures for the QGP, it is imperative that such correlations be used to identify special events and possible signatures. This requires a flexible detection system that can simultaneously measure many experimental observables. The physics goals dictate the design of star and it's experiment. To meet the design criteria, tracking, momentum analysis, and particle identification of most of the charged particles at midrapidity are necessary. The tracking must operate in conditions at higher than the expected maximum charged particle multiplicities for central Au + Au collisions. Particle identification of pions/kaons for p < 0.7 GeV/c and kaons/protons for p < 1 GeV/c, as well as measurement of decay particles and reconstruction of secondary vertices will be possible. A two-track resolution of 2 cm at 2 m radial distance from, the interaction is expected. Momentum resolution of {Delta}p/p {approximately} 0.02 at p = 0.1 GeV/c is required to accomplish the physics, and,{Delta}p/p of several percent at p = 10 GeV/c is sufficient to accurately measure the rapidly failing spectra at high Pt and particles from mini-jets and jets.

  20. LHCb: The LHCb Silicon Tracker: Running experience

    CERN Multimedia

    Saornil Gamarra, S

    2012-01-01

    The LHCb Silicon Tracker is part of the main tracking system of the LHCb detector at the LHC. It measures very precisely the particle trajectories coming from the interaction point in the region of high occupancies around the beam axis. After presenting our production and comissioning issues in TWEPP 2008, we report on our running experience. Focusing on electronic and hardware issues as well as operation and maintenance adversities, we describe the lessons learned and the pitfalls encountered after three years of successful operation.

  1. CMS Tracker Alignment Performance Results Summer 2016

    CERN Document Server

    CMS Collaboration

    2016-01-01

    The tracking system of the CMS detector provides excellent resolution for charged particle tracks and an efficient way of tagging jets. In order to reconstruct good quality tracks, the position and orientation of each silicon pixel and strip modules need to be determined with a precision of several micrometers. The performance of the CMS tracker alignment in 2016 using cosmic-ray data recorded at 0 T magnetic field and proton-proton collision data recorded at 3.8 T magnetic field has been studied. The data-driven validation of the results are presented. The time-dependent movement of the pixel detector's large-scale structure is demonstrated.

  2. Readout electronics for the ATLAS semiconductor tracker

    International Nuclear Information System (INIS)

    The binary readout architecture as a base-line and the analogue one as a fall-forward option have been adopted recently by the ATLAS semiconductor tracker group for the readout of silicon strip detectors. A brief overview of different architectures considered before as well as the status of the binary readout development will be presented. A new idea of the binary readout architecture employing a dual threshold scheme will be discussed and new results obtained for the full analogue readout chip realised in the DMILL technology will be reported. (orig.)

  3. Optimization Method for Solution Model of Laser Tracker Multilateration Measurement

    Science.gov (United States)

    Chen, Hongfang; Tan, Zhi; Shi, Zhaoyao; Song, Huixu; Yan, Hao

    2016-08-01

    Multilateration measurement using laser trackers suffers from a cumbersome solution method for high-precision measurements. Errors are induced by the self-calibration routines of the laser tracker software. This paper describes an optimization solution model for laser tracker multilateration measurement, which effectively inhibits the negative effect of this self-calibration, and further, analyzes the accuracy of the singular value decomposition for the described solution model. Experimental verification for the solution model based on laser tracker and coordinate measuring machine (CMM) was performed. The experiment results show that the described optimization model for laser tracker multilateration measurement has good accuracy control, and has potentially broad application in the field of laser tracker spatial localization.

  4. Reliability and validity of ten consumer activity trackers

    OpenAIRE

    Kooiman, Thea J.M.; Dontje, Manon L.; Sprenger, Siska R.; Krijnen, Wim P; van der Schans, Cees P.; de Groot, Martijn

    2015-01-01

    Background: Activity trackers can potentially stimulate users to increase their physical activity behavior. The aim of this study was to examine the reliability and validity of ten consumer activity trackers for measuring step count in both laboratory and free-living conditions. Method: Healthy adult volunteers (n = 33) walked twice on a treadmill (4.8 km/h) for 30 min while wearing ten different activity trackers (i.e. Lumoback, Fitbit Flex, Jawbone Up, Nike+ Fuelband SE, Misfit Shine, Withi...

  5. Modelling Structural Flexure Effects in CPV Sun Trackers

    OpenAIRE

    LUQUE-HEREDIA, Ignacio; Quéméré, G.; Magalhães, P.H.; Fraile de Lerma, Alberto; Hermanns, Lutz Karl Heinz; Alarcón Álvarez, Enrique; Luque López, Antonio

    2006-01-01

    Nowadays CPV trends mostly based in lens parqueted flat modules, enable the separate design of the sun tracker. To enable this possibility a set of specifications is to be prescribed for the tracker design team, which take into account fundamental requisites such as the maximum service loads both permanent and variable, the sun tracking accuracy and the tracker structural stiffness required to maintain the CPV array acceptance angle loss below a certain threshold. In its first part this paper...

  6. The ATLAS Semiconductor tracker: operations and performance

    CERN Document Server

    Pani, P; The ATLAS collaboration

    2013-01-01

    Tracker After more than 3 years of successful operation at the LHC, we report on the operation and performance of the Semi-Conductor Tracker (SCT) functioning in a high luminosity, high radiation environment. The SCT is part of the ATLAS experiment at CERN and is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals are processed in the front-end ABCD3TA ASICs, which use a binary readout architecture. Data is transferred to the off-detector readout electronics via optical fibers. We find 99.3% of the SCT modules are operational, noise occupancy and hit efficiency exceed the design specifications; the alignment is very cl...

  7. Semiconductor Strip Tracker Endcaps come to CERN

    CERN Multimedia

    P. Bell

    The first few months of 2006 saw the delivery to CERN of the final components of the ATLAS Semi-Conductor Tracker (SCT), namely the completed SCT end-caps. Regular ATLAS eNews readers will recall that the SCT barrel arrived in sections in 2005 and was assembled later that year (see the April 2005 and December 2005 issues, respectively.) And as reported in this issue of the eNews, the barrel SCT has recently been integrated with the barrel Transition Radiation Tracker. The end-caps were constructed in Liverpool (side C) and NIKHEF (side A), using components manufactured at many different sites across the world. End-cap C left Liverpool on Monday 20 February and arrived at CERN after a two-day journey by road and through the Channel Tunnel. Accelerations in all three dimensions were monitored during the trip, as was temperature and humidity inside the container; all values remained within pre-specified safe ranges. The end-cap was visually inspected upon arrival, with no obvious damage being seen. Subsequent ...

  8. Overview of the ATLAS Fast Tracker Project

    CERN Document Server

    Ancu, Lucian Stefan; The ATLAS collaboration

    2016-01-01

    The next LHC runs, with a significant increase in instantaneous luminosity, will provide a big challenge for the trigger and data acquisition systems of all the experiments. An intensive use of the tracking information at the trigger level will be important to keep high efficiency for interesting events despite the increase in multiple collisions per bunch crossing. In order to increase the use of tracks within the High Level Trigger, the ATLAS experiment planned the installation of a hardware processor dedicated to tracking: the Fast TracKer processor. The Fast Tracker is designed to perform full scan track reconstruction of every event accepted by the ATLAS first level hardware trigger. To achieve this goal the system uses a parallel architecture, with algorithms designed to exploit the computing power of custom Associative Memory chips, and modern field programmable gate arrays. The processor will provide computing power to reconstruct tracks with transverse momentum greater than 1 GeV in the whol...

  9. The ATLAS fast tracker processor design

    CERN Document Server

    Volpi, Guido; Albicocco, Pietro; Alison, John; Ancu, Lucian Stefan; Anderson, James; Andari, Nansi; Andreani, Alessandro; Andreazza, Attilio; Annovi, Alberto; Antonelli, Mario; Asbah, Needa; Atkinson, Markus; Baines, J; Barberio, Elisabetta; Beccherle, Roberto; Beretta, Matteo; Biesuz, Nicolo Vladi; Blair, R E; Bogdan, Mircea; Boveia, Antonio; Britzger, Daniel; Bryant, Partick; Burghgrave, Blake; Calderini, Giovanni; Camplani, Alessandra; Cavaliere, Viviana; Cavasinni, Vincenzo; Chakraborty, Dhiman; Chang, Philip; Cheng, Yangyang; Citraro, Saverio; Citterio, Mauro; Crescioli, Francesco; Dawe, Noel; Dell'Orso, Mauro; Donati, Simone; Dondero, Paolo; Drake, G; Gadomski, Szymon; Gatta, Mauro; Gentsos, Christos; Giannetti, Paola; Gkaitatzis, Stamatios; Gramling, Johanna; Howarth, James William; Iizawa, Tomoya; Ilic, Nikolina; Jiang, Zihao; Kaji, Toshiaki; Kasten, Michael; Kawaguchi, Yoshimasa; Kim, Young Kee; Kimura, Naoki; Klimkovich, Tatsiana; Kolb, Mathis; Kordas, K; Krizka, Karol; Kubota, T; Lanza, Agostino; Li, Ho Ling; Liberali, Valentino; Lisovyi, Mykhailo; Liu, Lulu; Love, Jeremy; Luciano, Pierluigi; Luongo, Carmela; Magalotti, Daniel; Maznas, Ioannis; Meroni, Chiara; Mitani, Takashi; Nasimi, Hikmat; Negri, Andrea; Neroutsos, Panos; Neubauer, Mark; Nikolaidis, Spiridon; Okumura, Y; Pandini, Carlo; Petridou, Chariclia; Piendibene, Marco; Proudfoot, James; Rados, Petar Kevin; Roda, Chiara; Rossi, Enrico; Sakurai, Yuki; Sampsonidis, Dimitrios; Saxon, James; Schmitt, Stefan; Schoening, Andre; Shochet, Mel; Shoijaii, Jafar; Soltveit, Hans Kristian; Sotiropoulou, Calliope-Louisa; Stabile, Alberto; Swiatlowski, Maximilian J; Tang, Fukun; Taylor, Pierre Thor Elliot; Testa, Marianna; Tompkins, Lauren; Vercesi, V; Wang, Rui; Watari, Ryutaro; Zhang, Jianhong; Zeng, Jian Cong; Zou, Rui; Bertolucci, Federico

    2015-01-01

    The extended use of tracking information at the trigger level in the LHC is crucial for the trigger and data acquisition (TDAQ) system to fulfill its task. Precise and fast tracking is important to identify specific decay products of the Higgs boson or new phenomena, as well as to distinguish the contributions coming from the many collisions that occur at every bunch crossing. However, track reconstruction is among the most demanding tasks performed by the TDAQ computing farm; in fact, complete reconstruction at full Level-1 trigger accept rate (100 kHz) is not possible. In order to overcome this limitation, the ATLAS experiment is planning the installation of a dedicated processor, the Fast Tracker (FTK), which is aimed at achieving this goal. The FTK is a pipeline of high performance electronics, based on custom and commercial devices, which is expected to reconstruct, with high resolution, the trajectories of charged-particle tracks with a transverse momentum above 1 GeV, using the ATLAS inner tracker info...

  10. The ATLAS SemiConductorTracker

    CERN Document Server

    Mikuz, M

    2004-01-01

    The ATLAS SemiConductor Tracker (SCT) is presented. About 16000 silicon micro-strip sensors with a total active surface of over 60 m /sup 2/ and with 6.3 million read-out channels are built into 4088 modules arranged into four barrel layers and nine disks covering each of the forward regions up to an eta of 2.5. Challenges are imposed by the hostile radiation environment with particle fluences up to 2*10 /sup 14/ cm/sup -2/ 1 MeV neutron NIEL equivalent and 100 kGy TID, the 25 ns LHC bunch crossing time and the need for a hermetic, lightweight tracker. The solution adopted is carefully designed strip detectors operated at -7 degrees C, biased up to 500 V and read out by binary rad-hard fast BiCMOS electronics. A zero-CTE carbon fibre structure provides mechanical support. 30 kW of power are supplied on aluminium/Kapton tapes and cooled by C/sub 3/F/sub 8/ evaporative cooling. Data and commands are transferred by optical links. Prototypes of detector modules have been built, irradiated to the maximum expected ...

  11. Success potential of automated star pattern recognition

    Science.gov (United States)

    Van Bezooijen, R. W. H.

    1986-01-01

    A quasi-analytical model is presented for calculating the success probability of automated star pattern recognition systems for attitude control of spacecraft. The star data is gathered by an imaging star tracker (STR) with a circular FOV capable of detecting 20 stars. The success potential is evaluated in terms of the equivalent diameters of the FOV and the target star area ('uniqueness area'). Recognition is carried out as a function of the position and brightness of selected stars in an area around each guide star. The success of the system is dependent on the resultant pointing error, and is calculated by generating a probability distribution of reaching a threshold probability of an unacceptable pointing error. The method yields data which are equivalent to data available with Monte Carlo simulatins. When applied to the recognition system intended for use on the Space IR Telescope Facility it is shown that acceptable pointing, to a level of nearly 100 percent certainty, can be obtained using a single star tracker and about 4000 guide stars.

  12. 3D Technology for intelligent trackers

    Energy Technology Data Exchange (ETDEWEB)

    Lipton, Ronald; /Fermilab

    2010-09-01

    At Super-LHC luminosity it is expected that the standard suite of level 1 triggers for CMS will saturate. Information from the tracker will be needed to reduce trigger rates to satisfy the level 1 bandwidth. Tracking trigger modules which correlate information from closely-spaced sensor layers to form an on-detector momentum filter are being developed by several groups. We report on a trigger module design which utilizes three dimensional integrated circuit technology incorporating chips which are connected both to the top and bottom sensor, providing the ability to filter information locally. A demonstration chip, the VICTR, has been submitted to the Chartered/Tezzaron two-tier 3D run coordinated by Fermilab. We report on the 3D design concept, the status of the VICTR chip and associated sensor integration utilizing oxide bonding.

  13. The ATLAS Semiconductor Tracker: operations and performance

    CERN Document Server

    Pani, P; The ATLAS collaboration

    2013-01-01

    After more than 3 years of successful operation at 2 the LHC, we report on the operation and performance of the Semi-Conductor Tracker (SCT) functioning in a high luminosity, 4 high radiation environment. The SCT is part of the inner tracking system of the ATLAS 6 experiment at CERN and is constructed of 4088 silicon detector modules for a total of 6.3 million strips. We find 99.3% of the 8 SCT modules are operational, noise occupancy and hit efficiency exceed the design specifications; the alignment is very close to 10 the ideal to allow on-line track reconstruction and invariant mass determination. We will report on the operation and performance 12 of the detector including an overview of the issues encountered. The observables employed to monitor online and offline the 14 quality and the performance of the data acquired by the SCT will be described and discussed.

  14. Ageing of the LHCb outer tracker

    CERN Document Server

    Blom, M R

    2009-01-01

    The modules of the LHCb outer tracker have shown to suffer severe gain loss under moderate irradiation. This process is called ageing. Ageing of the modules results from contamination of the gas system by glue, araldite AY 103-1, used in their construction. In this thesis the ageing process will be shown. The schemes known to reduce, reverse, or prevent ageing have been investigated to determine their effect on the detector performance. The addition of O2 to the gas mixture lowers the detector response by an acceptable amount and does not affect the gas transport properties significantly. The ageing rate is decreased after extensive flushing and HV training could eventually repair the irradiation damage. The risks of HV training have been assessed. Furthermore, several gaseous and aquatic additions have been tested for their capability to prevent, or moderate ageing, but none showed significant improvement.

  15. Operation and performance of the CMS tracker

    CERN Document Server

    Malberti, Martina

    2014-01-01

    The CMS silicon tracker is the largest silicon detector ever built. It consists of an inner pixel detector, with 66 million readout channels, and an outer 200 m$^{2}$ silicon strip detector with 10 million channels. The successful operation of this detector during the first three years of LHC running with proton-proton and heavy ion collisions is discussed. Results include operational challenges encountered during data taking that influenced the active fraction and readout efficiency of the detectors. Details are given on the performance at high occupancy with respect to local observables, such as signal-to-noise ratio and hit reconstruction efficiency, and on radiation effects with respect to the evolution of power consumption, sensor bias, readout thresholds and leakage current.

  16. T2K near detector tracker

    Energy Technology Data Exchange (ETDEWEB)

    Blaszczyk, Flor de Maria [IRFU/SPP, CEA-Saclay, bat. 141, 91191 Gif-sur-Yvette Cedex (France)

    2010-07-01

    Tokai to Kamioka (T2K) is a new generation neutrino oscillation experiment that started collecting data in 2009 in Japan. A {nu}{mu} beam produced by an intense proton beam colliding onto a target is directed from J-PARC (Tokai) to the 50 kt water Cerenkov detector Super Kamiokande at a distance of 295 km. T2K's main goals are measuring one of the last unknown parameters of the PMNS matrix {Theta}{sub 13} by using {nu}e appearance in the beam, and measuring precisely {Delta}m{sup 2}23 and {Theta}{sub 23} by using {nu}{mu} disappearance. A near detector (ND280) placed in a 0.2 T magnetic field is located at 280 m from the target to allow the characterisation of the neutrino beam before oscillation. In particular, the detector measures the neutrino energy spectra, beam flavor composition, background and cross-sections. ND280 started taking data at the end of 2009. An essential element of ND280 is the tracker, composed of two fine grained detectors (FGD) to serve as targets for neutrino interactions and measure cross-sections, and three time projection chambers (TPC) to track and identify charged particles. The TPCs' readout planes are equipped with Micromegas micro-pattern detectors, achieving a total active surface of 9 m{sup 2}. The first FGD is made of scintillator bars only whereas the second one includes water targets. The performance of the tracker with cosmic ray and neutrino data will be presented. (author)

  17. Reliability and validity of ten consumer activity trackers

    NARCIS (Netherlands)

    Kooiman, Thea J.M.; Dontje, Manon L.; Sprenger, Siska R.; Krijnen, Wim P.; Schans, Cees P. van der; Groot, Martijn de

    2015-01-01

    Background: Activity trackers can potentially stimulate users to increase their physical activity behavior. The aim of this study was to examine the reliability and validity of ten consumer activity trackers for measuring step count in both laboratory and free-living conditions. Method: Healthy adul

  18. Study of prototype sensors for the Upstream Tracker Upgrade

    CERN Document Server

    Abba, Andrea; Blusk, Steven R.; Bursche, Albert; Davis, Adam; Dendek, Adam Mateusz; Dey, Biplab; Ely, Scott Edward; Forshaw, Dean Charles; Fu, Jinlin; Kelsey, Matthew Jordan; Lionetto, Federica; Manning Jr, Peter Michael; Mountain, Ray; Neri, Nicola; Papula, Alana Leigh; Petruzzo, Marco; Pikies, Malgorzata Maria; Rudolph, Matthew Scott; Sokoloff, Michael David; Stone, Sheldon; Szumlak, Tomasz; Wang, Jianchun

    2016-01-01

    Three testbeams were carried out in 2015 to test the performance of prototype sensors for the Upstream Tracker. Two of the testbeams were devoted to studying full size n-in-p sensors, and one was devoted to testing mini-sensors, all from Hamamatsu. Results on the performance of these Upstream Tracker sensor prototypes are presented.

  19. Optimization of the silicon sensors for the CMS tracker

    Energy Technology Data Exchange (ETDEWEB)

    Albergo, S.; Angarano, M.; Azzi, P.; Babucci, E.; Bacchetta, N.; Bader, A.; Bagliesi, G.; Basti, A.; Biggeri, U.; Biino, C.; Bilei, G.M.; Bisello, D.; Boemi, D.; Bosi, F.; Borello, L.; Braibant, S.; Breuker, H.; Brunetti, M.T.; Bruzzi, M.; Buffini, A.; Busoni, S.; Candelori, A.; Caner, A.; Castaldi, R.; Castro, A.; Catacchini, E.; Checcucci, B.; Ciampolini, P.; Civinini, C.; Costa, M.; Creanza, D.; D' Alessandro, R.; DeMaria, N.; Palma, M. de; Dell' Orso, R.; Dutta, S.; Favro, G.; Fiore, L.; Focardi, E.; French, M.; Freudenreich, K.; Frey, A. E-mail: ariane.frey@cern.ch; Friedl, M.; Fuertjes, A.; Giassi, A.; Giorgi, M.; Giraldo, A.; Glessing, W.; Gu, W.H.; Hall, G.; Hammarstrom, R.; Hebbeker, T.; Honkanen, A.; Honma, A.; Hrubec, J.; Huhtinen, M.; Kaminsky, A.; Karimaki, V.; Koenig, St.; Krammer, M.; Lariccia, P.; Lenzi, M.; Loreti, M.; Luebelsmeyer, K.; Lustermann, W.; Maettig, P.; Maggi, G.; Mannelli, M.; Mantovani, G.; Marchioro, A.; Mariotti, C.; Martignon, G.; Mc Evoy, B.; Meschini, M.; Messineo, A.; Migliore, E.; My, S.; Neviani, A.; Paccagnella, A.; Palla, F.; Pandoulas, D.; Papi, A.; Parrini, G.; Passeri, D.; Pernicka, M.; Pieri, M.; Piperov, S.; Potenza, R.; Radicci, V.; Raffaelli, F.; Raymond, M.; Rizzo, F.; Santocchia, A.; Segneri, G.; Selvaggi, G.; Servoli, L.; Sguazzoni, G.; Siedling, R.; Silvestris, L.; Starodumov, A.; Stavitski, I.; Surrow, B.; Tempesta, P.; Tonelli, G.; Tricomi, A.; Tuominiemi, J.; Tuuva, T.; Verdini, P.G.; Viertel, G.; Xie, Z.; Yahong, Li; Watts, S.; Wittmer, B

    2001-07-01

    The CMS experiment at the LHC will comprise a large silicon strip tracker. This article highlights some of the results obtained in the R and D studies for the optimization of its silicon sensors. Measurements of the capacitances and of the high voltage stability of the devices are presented before and after irradiation to the dose expected after the full lifetime of the tracker.

  20. Autonomous Spacecraft Navigation With Pulsars

    CERN Document Server

    Becker, Werner; Jessner, Axel

    2013-01-01

    An external reference system suitable for deep space navigation can be defined by fast spinning and strongly magnetized neutron stars, called pulsars. Their beamed periodic signals have timing stabilities comparable to atomic clocks and provide characteristic temporal signatures that can be used as natural navigation beacons, quite similar to the use of GPS satellites for navigation on Earth. By comparing pulse arrival times measured on-board a spacecraft with predicted pulse arrivals at a reference location, the spacecraft position can be determined autonomously and with high accuracy everywhere in the solar system and beyond. The unique properties of pulsars make clear already today that such a navigation system will have its application in future astronautics. In this paper we describe the basic principle of spacecraft navigation using pulsars and report on the current development status of this novel technology.

  1. Lunar Navigator - A Miniature, Fully Autonomous, Lunar Navigation, Surveyor, and Range Finder System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm proposes to design and develop a fully autonomous Lunar Navigator based on our MicroMak miniature star sensor and a gravity gradiometer similar to one on...

  2. Trigeminal autonomic cephalgias

    OpenAIRE

    Benoliel, Rafael

    2012-01-01

    1. Trigeminal autonomic cephalgias (TACs) are headaches/facial pains classified together based on:a suspected common pathophysiology involving the trigeminovascular system, the trigeminoparasympathetic reflex and centres controlling circadian rhythms;a similar clinical presentation of trigeminal pain, and autonomic activation.

  3. Testing for autonomic neuropathy

    DEFF Research Database (Denmark)

    Hilsted, J

    1984-01-01

    Autonomic neuropathy is a common complication in long-term diabetes, about 30% of the patients showing measurable signs of autonomic dysfunction after 10 years duration of disease. The diagnosis is often difficult to establish because clinical symptoms generally occur late in the course...

  4. The Tracker in the Trigger of LHCb

    CERN Document Server

    Hommels, L B A; Merk, M; Tuning, N

    2006-01-01

    Situated at the LHC, the LHCb experiment is to measure B meson decay with high statistics. Its primary goals are the establishment of CP violation parameters with high precision, and the study of rare B meson decays to look for physics processes beyond the Standard Model. In this thesis, an overview is given on the Outer Tracker (OT) subdetector of the LHCb experiment. The requirements on efficiency, resolution, occupancy and radiation hardness are discussed. The detector design and readout electronics of the OT, a gas filled detector, are presented. To meet the requirements, straw tube cathodes of 4.9mm inner diameter surround the anode wires. The tubes are filled with an Argon based counting gas at atmospheric pressure, allowing for a channel resolution better then 200mum. To limit multiple scattering, the OT is built from lightweight composite materials, resulting in a momentum resolution of dp/p < 0.6% for p between 0 and 150 GeV/c. From extensive ageing tests involving single channels as well as entir...

  5. Climate Action Tracker Update. Climate Shuffle

    Energy Technology Data Exchange (ETDEWEB)

    Hoehne, N.; Fekete, H.; Vieweg, M.; Hare, B.; Schaeffer, M.; Rocha, M.; Larkin, J.; Guetschow, J.; Jeffery, L.

    2011-11-15

    The Climate Action Tracker (CAT) compares and assesses national and global action against a range of different climate targets across all relevant time frames, starting with an ongoing analysis of countries' current emission reduction pledges. National action on climate change mitigation appears to be joining the international climate negotiations in the new and ever popular 'climate shuffle' dance. It involves maximum effort and motion while staying in the same spot, or even, in some cases, going backwards. Recent emissions trends and estimates of the effects of those policies in place and proposed lead to a new estimate that warming is likely to approach 4C by 2100, significantly above the warming that would result from full implementation of the pledges (3.3C). The continuous global fossil-fuel intensive development of the past decade suggests that high warming levels of 4C are more plausible than assuming full implementation of current pledges. Evidence is ever increasing that existing and planned policies are not sufficient for countries to meet these pledges.

  6. 3D Monitoring of LHCb Inner Tracker

    CERN Multimedia

    Sainvitu, Pascal

    2015-01-01

    The positions of the Inner Tracker (IT) detectors of the LHCb experiment installed in the LHC at CERN are impacted by the LHCb dipole magnet powering. In the past the movements of the stations have been measured using standard survey methods during magnet tests in shutdown periods. But the survey targets are visible only in very narrow spaces and the access to the IT is very difficult, even impossible in the central region when the detector is closed. Finally the precision of the standard survey measurement is affected by the poor configuration. In 2013 and 2014, during the first long shutdown of the LHC (LS1), the CERN Survey team (EN/MEF-SU) in collaboration with the LHCb Technical Coordination and the EPFL (Ecole Polytechnique Fédérale de LAUSANNE, CH), developed a permanent monitoring system which has been tested and installed in order to allow the 3D position measurement of the IT stations, even during the run periods, with a precision of 100 microns at 1 sigma level. The 3D Monitoring system of the LH...

  7. ATLAS Silicon Microstrip Tracker Operation and Performance

    CERN Document Server

    Barone, G; The ATLAS collaboration

    2013-01-01

    The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices of the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of $4088$ silicon detector modules for a total of 6.3 million channels. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel ($4$ cylinders) and two end-cap systems (9 disks on each). The current results from the successful operation of the SCT Detector at the LHC and its status after three years of operation will be presented. The operation of the detector including an overview of the main issues encountered is reported. The main emphasis is be given to the tracking performance of the SCT and the data quality during the $>2$ years of data taking of proton-proton collision data at $7$ TeV (and short periods of heavy ion collisions). The SCT has been fully operational throughout a...

  8. ATLAS Silicon Microstrip Tracker Operation and Performance

    CERN Document Server

    Chalupkova, I; The ATLAS collaboration

    2012-01-01

    The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals from the strips are processed in the front-end ASICS ABCD3TA, working in the binary readout mode. Data is transferred to the off-detector readout electronics via optical fibers. The completed SCT has been installed inside the ATLAS experimental cavern since 2007 and has been operational since then. Calibration data has been taken regularly and analyzed to determine the noise performance of the ...

  9. ATLAS Silicon Microstrip Tracker Operation and Performance

    CERN Document Server

    NAGAI, K; The ATLAS collaboration

    2012-01-01

    The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar p-in-n technology. The signals from the strips are processed in the front-end ASICS ABCD3TA, working in the binary readout mode. Data is transferred to the off-detector readout electronics via optical fibres. The completed SCT has been installed inside the ATLAS experimental cavern since 2007 and has been operational since then. Calibration data has been taken regularly and analysed to determine the noise performance of the ...

  10. The ATLAS semiconductor tracker: operations and performance

    CERN Document Server

    D'Auria, S; The ATLAS collaboration

    2012-01-01

    The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). The SCT silicon micro-strip sensors are processed in the planar {it p}-in-{it n} technology. The signals are processed in the front-end ASICS ABCD3TA, working in binary readout mode. Data is transferred to the off-detector readout electronics via optical fibres. We find 99.3% of the SCT modules are operational, noise occupancy and hit efficiency exceed the design specifications. In the talk the current results from the successful operation of the SCT Detector at the LHC and its status af...

  11. ATLAS Silicon Microstrip Tracker Operation and Performance

    CERN Document Server

    Barone, G; The ATLAS collaboration

    2013-01-01

    The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices in the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million strips. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each end of the barrel). In the talk the current results from the successful operation of the SCT Detector at the LHC and its status after three years of operation will be presented. We will report on the operation of the detector including an overview of the issues we encountered and the observation of significant increases in leakage currents (as expected) from bulk damage due to non-ionising radiation. The main emphasis will be given to the tracking performance of the SCT and the data quality during the >2 ye...

  12. The DAMPE silicon-tungsten tracker

    Science.gov (United States)

    Azzarello, P.; Ambrosi, G.; Asfandiyarov, R.; Bernardini, P.; Bertucci, B.; Bolognini, A.; Cadoux, F.; Caprai, M.; De Mitri, I.; Domenjoz, M.; Dong, Y.; Duranti, M.; Fan, R.; Fusco, P.; Gallo, V.; Gargano, F.; Gong, K.; Guo, D.; Husi, C.; Ionica, M.; La Marra, D.; Loparco, F.; Marsella, G.; Mazziotta, M. N.; Mesa, J.; Nardinocchi, A.; Nicola, L.; Pelleriti, G.; Peng, W.; Pohl, M.; Postolache, V.; Qiao, R.; Surdo, A.; Tykhonov, A.; Vitillo, S.; Wang, H.; Weber, M.; Wu, D.; Wu, X.; Zhang, F.

    2016-09-01

    The DArk Matter Particle Explorer (DAMPE) is a spaceborne astroparticle physics experiment, launched on 17 December 2015. DAMPE will identify possible dark matter signatures by detecting electrons and photons in the 5 GeV-10 TeV energy range. It will also measure the flux of nuclei up to 100 TeV, for the study of the high energy cosmic ray origin and propagation mechanisms. DAMPE is composed of four sub-detectors: a plastic strip scintillator, a silicon-tungsten tracker-converter (STK), a BGO imaging calorimeter and a neutron detector. The STK is composed of six tracking planes of 2 orthogonal layers of single-sided micro-strip detectors, for a total detector surface of ca. 7 m2. The STK has been extensively tested for space qualification. Also, numerous beam tests at CERN have been done to study particle detection at silicon module level, and at full detector level. After description of the DAMPE payload and its scientific mission, we will describe the STK characteristics and assembly. We will then focus on some results of single ladder performance tests done with particle beams at CERN.

  13. ATLAS silicon microstrip tracker operation and performance

    Science.gov (United States)

    Barone, Gaetano

    2013-12-01

    The Semi-Conductor Tracker (SCT) is a silicon strip detector and one of the key precision tracking devices of the Inner Detector of the ATLAS experiment at CERN LHC. The SCT is constructed of 4088 silicon detector modules for a total of 6.3 million channels. Each module is designed, constructed and tested to operate as a stand-alone unit, mechanically, electrically, optically and thermally. The modules are mounted into two types of structures: one barrel (4 cylinders) and two end-cap systems (9 disks on each). The current results from the successful operation of the SCT Detector at the LHC and its status after three years of operation will be presented. The operation of the detector including an overview of the main issues encountered is reported. The main emphasis is given to the tracking performance of the SCT and the data quality during the >2 years of data taking of proton-proton collision data at 7 TeV (and short periods of heavy ion collisions). The SCT has been fully operational throughout all data taking periods, delivering high quality tracking data.

  14. Tracker electronics testing at Imperial College London

    CERN Multimedia

    PPARC, UK

    2006-01-01

    Jonathon Fulcher and Rob Bainbridge testing a rack of CMS Tracker readout electronics at Imperial College London. The signals from the front end APV chips will be transmitted optically to racks of electronics ~100m away in an adjacent underground cavern where they are fed into ~20 crates where 500 CMS Front End Driver boards (FEDs) are located. The FED inputs are 8 fibre ribbons, each ribbon consisting of 12 fibres, each fibre carrying the serially multiplexed data originating from 2 APVs. To test the FEDs special tester boards have been designed to produce simulated APV data in optical form. In the picture the yellow cables are the fibres, which originate from the FED tester boards on the left hand side of the crate as 96 individual fibres, which are then combined into the 8 fibre ribbons feeding the FED board on the right hand side of the crate. Fig. 2 shows an APV25 test board mounted in the X-ray irradiation setup, Fig. 3 the X-ray machine where the chips are irradiated and Fig. 4 the MGPA (Multi-Gain Pre...

  15. Test of the Inner Tracker Silicon Microstrip Modules

    CERN Document Server

    Albergo, Sebastiano; Azzurri, Paolo; Bagliesi, Giuseppe; Bellan, Riccardo; Benedetti, Daniele; Benotto, Franco; Benucci, Leonardo; Bernardini, Jacopo; Bonato, Alessio; Brasolin, A; Chiorboli, Massimiliano; Civinini, Carlo; Costa, Marco; Creanza, Donato; D'Alfonso, Mariarosaria; De Palma, Mauro; Dell'Orso, Roberto; Demaria, Natale; Fiore, Luigi; Foà, Lorenzo; Galanti, Mario; Gatto Rotondo, Giuliana; Gerbaudo, Davide; Giammanco, Andrea; Giordano, Domenico; Kaminski, A; Karaevski, S; Lenzi, Piergiulio; Ligabue, Franco; Loreti, Maurizio; Mangano, Boris; Manolescu, Florentina; Marchettini, Cristiano; Meschini, Marco; Migliore, Ernesto; My, Salvatore; Preda, M; Radicci, Valeria; Ranieri, Riccardo; Reznikov, Sergey; Rizzi, Andrea; Saizu, Mirela Angela; Santocchia, Attilio; Segneri, Gabriele; Sguazzoni, Giacomo; Spagnolo, Paolo; Tenchini, Roberto; Tricomi, Alessia; Venturi, Andrea

    2009-01-01

    The inner portion of the CMS microstrip Tracker consists of 3540 silicon detector modules; its construction has been under full responsibility of seven INFN (Istituto Nazionale di Fisica Nucleare) and University laboratories in Italy. In this note procedures and strategies, which were developed and perfected to qualify the Tracker Inner Barrel and Inner Disks modules for installation, are described. In particular the tests required to select highly reliable detector modules are illustrated and a summary of the results from the full Inner Tracker module test is presented.

  16. Evaluation of a remote webcam-based eye tracker

    DEFF Research Database (Denmark)

    Skovsgaard, Henrik; Agustin, Javier San; Johansen, Sune Alstrup;

    2011-01-01

    In this paper we assess the performance of an open-source gaze tracker in a remote (i.e. table-mounted) setup, and compare it with two other commercial eye trackers. An experiment with 5 subjects showed the open-source eye tracker to have a significantly higher level of accuracy than one of the c...... of the commercial systems, Mirametrix S1, but also a higher error rate than the other commercial system, a Tobii T60. We conclude that the web-camera solution may be viable for people who need a substitute for the mouse input but cannot afford a commercial system....

  17. Autonomous linear lossless systems

    OpenAIRE

    Rao, Shodhan; Rapisarda, Paolo

    2008-01-01

    We define a lossless autonomous system as one having a quadratic differential form associated with it called an energy function, which is positive and which is conserved. We define an oscillatory system as one which has all its trajectories bounded on the entire time axis. In this paper, we show that an autonomous system is lossless if and only if it is oscillatory. Next we discuss a few properties of energy functions of autonomous lossless systems and a suitable way of splitting a given ener...

  18. Autonomous surveillance for biosecurity.

    Science.gov (United States)

    Jurdak, Raja; Elfes, Alberto; Kusy, Branislav; Tews, Ashley; Hu, Wen; Hernandez, Emili; Kottege, Navinda; Sikka, Pavan

    2015-04-01

    The global movement of people and goods has increased the risk of biosecurity threats and their potential to incur large economic, social, and environmental costs. Conventional manual biosecurity surveillance methods are limited by their scalability in space and time. This article focuses on autonomous surveillance systems, comprising sensor networks, robots, and intelligent algorithms, and their applicability to biosecurity threats. We discuss the spatial and temporal attributes of autonomous surveillance technologies and map them to three broad categories of biosecurity threat: (i) vector-borne diseases; (ii) plant pests; and (iii) aquatic pests. Our discussion reveals a broad range of opportunities to serve biosecurity needs through autonomous surveillance. PMID:25744760

  19. Highly Autonomous Systems Workshop

    Science.gov (United States)

    Doyle, R.; Rasmussen, R.; Man, G.; Patel, K.

    1998-01-01

    It is our aim by launching a series of workshops on the topic of highly autonomous systems to reach out to the larger community interested in technology development for remotely deployed systems, particularly those for exploration.

  20. Autonomic Nervous System Disorders

    Science.gov (United States)

    ... with breathing and swallowing Erectile dysfunction in men Autonomic nervous system disorders can occur alone or as the result of another disease, such as Parkinson's disease, alcoholism and diabetes. Problems can affect either part ...

  1. The Data Quality Monitoring for the CMS Silicon Strip Tracker

    CERN Document Server

    Adler, V; Bainbridge, R; Benucci, L; Borgia, M A; Borrello, L; Cole, J; Cripps, N; Delmeire, E; Dero, V; Dutta, S; Giordano, D; Hammad, G H; Hashemi, H; Le Bihan, A C; Le Bourgeois, M; Palmonari, F; Pierro, A; Zito, G

    2009-01-01

    The CMS Silicon Strip Tracker (SST), consisting of more than 10 million channels, is organized in about 15,000 detector modules and it is the largest silicon strip tracker ever built for high energy physics experiments. The Data Quality Monitoring system for the Tracker has been developed within the CMS Software framework. More than 100,000 monitorable quantities need to be managed by the DQM system that organizes them in a hierarchical structure reflecting the detector arrangement in subcomponents and the various levels of data processing. Monitorable quantities computed at the level of individual detectors are processed to extract automatic quality checks and summary results that can be visualized with specialized graphical user interfaces. In view of the great complexity of the CMS Tracker detector the standard visualization tools based on histograms have been complemented with 2 and 3 dimensional graphical images of the subdetector that can show the whole detector down to single channel resolution. The fu...

  2. Performance studies of the CMS Strip Tracker before installation

    CERN Document Server

    Adam, Wolfgang; Dragicevic, Marko; Friedl, Markus; Fruhwirth, R; Hansel, S; Hrubec, Josef; Krammer, Manfred; Oberegger, Margit; Pernicka, Manfred; Schmid, Siegfried; Stark, Roland; Steininger, Helmut; Uhl, Dieter; Waltenberger, Wolfgang; Widl, Edmund; Van Mechelen, Pierre; Cardaci, Marco; Beaumont, Willem; de Langhe, Eric; de Wolf, Eddi A; Delmeire, Evelyne; Hashemi, Majid; Bouhali, Othmane; Charaf, Otman; Clerbaux, Barbara; Dewulf, Jean-Paul; Elgammal, Sherif; Hammad, Gregory Habib; de Lentdecker, Gilles; Marage, Pierre Edouard; Vander Velde, Catherine; Vanlaer, Pascal; Wickens, John; Adler, Volker; Devroede, Olivier; De Weirdt, Stijn; D'Hondt, Jorgen; Goorens, Robert; Heyninck, Jan; Maes, Joris; Mozer, Matthias Ulrich; Tavernier, Stefaan; Van Lancker, Luc; Van Mulders, Petra; Villella, Ilaria; Wastiels, C; Bonnet, Jean-Luc; Bruno, Giacomo; De Callatay, Bernard; Florins, Benoit; Giammanco, Andrea; Gregoire, Ghislain; Keutgen, Thomas; Kcira, Dorian; Lemaitre, Vincent; Michotte, Daniel; Militaru, Otilia; Piotrzkowski, Krzysztof; Quertermont, L; Roberfroid, Vincent; Rouby, Xavier; Teyssier, Daniel; Daubie, Evelyne; Anttila, Erkki; Czellar, Sandor; Engstrom, Pauli; Harkonen, J; Karimaki, V; Kostesmaa, J; Kuronen, Auli; Lampen, Tapio; Linden, Tomas; Luukka, Panja-Riina; Maenpaa, T; Michal, Sebastien; Tuominen, Eija; Tuominiemi, Jorma; Ageron, Michel; Baulieu, Guillaume; Bonnevaux, Alain; Boudoul, Gaelle; Chabanat, Eric; Chabert, Eric Christian; Chierici, Roberto; Contardo, Didier; Della Negra, Rodolphe; Dupasquier, Thierry; Gelin, Georges; Giraud, Noël; Guillot, Gérard; Estre, Nicolas; Haroutunian, Roger; Lumb, Nicholas; Perries, Stephane; Schirra, Florent; Trocme, Benjamin; Vanzetto, Sylvain; Agram, Jean-Laurent; Blaes, Reiner; Drouhin, Frédéric; Ernenwein, Jean-Pierre; Fontaine, Jean-Charles; Berst, Jean-Daniel; Brom, Jean-Marie; Didierjean, Francois; Goerlach, Ulrich; Graehling, Philippe; Gross, Laurent; Hosselet, J; Juillot, Pierre; Lounis, Abdenour; Maazouzi, Chaker; Olivetto, Christian; Strub, Roger; Van Hove, Pierre; Anagnostou, Georgios; Brauer, Richard; Esser, Hans; Feld, Lutz; Karpinski, Waclaw; Klein, Katja; Kukulies, Christoph; Olzem, Jan; Ostapchuk, Andrey; Pandoulas, Demetrios; Pierschel, Gerhard; Raupach, Frank; Schael, Stefan; Schwering, Georg; Sprenger, Daniel; Thomas, Maarten; Weber, Markus; Wittmer, Bruno; Wlochal, Michael; Beissel, Franz; Bock, E; Flugge, G; Gillissen, C; Hermanns, Thomas; Heydhausen, Dirk; Jahn, Dieter; Kaussen, Gordon; Linn, Alexander; Perchalla, Lars; Poettgens, Michael; Pooth, Oliver; Stahl, Achim; Zoeller, Marc Henning; Buhmann, Peter; Butz, Erik; Flucke, Gero; Hamdorf, Richard Helmut; Hauk, Johannes; Klanner, Robert; Pein, Uwe; Schleper, Peter; Steinbruck, G; Blum, P; De Boer, Wim; Dierlamm, Alexander; Dirkes, Guido; Fahrer, Manuel; Frey, Martin; Furgeri, Alexander; Hartmann, Frank; Heier, Stefan; Hoffmann, Karl-Heinz; Kaminski, Jochen; Ledermann, Bernhard; Liamsuwan, Thiansin; Muller, S; Muller, Th; Schilling, Frank-Peter; Simonis, Hans-Jürgen; Steck, Pia; Zhukov, Valery; Cariola, P; De Robertis, Giuseppe; Ferorelli, Raffaele; Fiore, Luigi; Preda, M; Sala, Giuliano; Silvestris, Lucia; Tempesta, Paolo; Zito, Giuseppe; Creanza, Donato; De Filippis, Nicola; De Palma, Mauro; Giordano, Domenico; Maggi, Giorgio; Manna, Norman; My, Salvatore; Selvaggi, Giovanna; Albergo, Sebastiano; Chiorboli, Massimiliano; Costa, Salvatore; Galanti, Mario; Giudice, Nunzio; Guardone, Nunzio; Noto, Francesco; Potenza, Renato; Saizu, Mirela Angela; Sparti, V; Sutera, Concetta; Tricomi, Alessia; Tuve, Cristina; Brianzi, Mirko; Civinini, Carlo; Maletta, Fernando; Manolescu, Florentina; Meschini, Marco; Paoletti, Simone; Sguazzoni, Giacomo; Broccolo, B; Ciulli, Vitaliano; D'Alessandro, Raffaello; Focardi, Ettore; Frosali, Simone; Genta, Chiara; Landi, Gregorio; Lenzi, Piergiulio; Macchiolo, Anna; Magini, Nicolo; Parrini, Giuliano; Scarlini, Enrico; Cerati, Giuseppe Benedetto; Azzi, Patrizia; Bacchetta, Nicola; Candelori, Andrea; Dorigo, Tommaso; Kaminsky, A; Karaevski, S; Khomenkov, Volodymyr; Reznikov, Sergey; Tessaro, Mario; Bisello, Dario; De Mattia, Marco; Giubilato, Piero; Loreti, Maurizio; Mattiazzo, Serena; Nigro, Massimo; Paccagnella, Alessandro; Pantano, Devis; Pozzobon, Nicola; Tosi, Mia; Bilei, Gian Mario; Checcucci, Bruno; Fano, Livio; Servoli, Leonello; Ambroglini, Filippo; Babucci, Ezio; Benedetti, Daniele; Biasini, Maurizio; Caponeri, Benedetta; Covarelli, Roberto; Giorgi, Marco; Lariccia, Paolo; Mantovani, Giancarlo; Marcantonini, Marta; Postolache, Vasile; Santocchia, Attilio; Spiga, Daniele; Bagliesi, Giuseppe; Balestri, Gabriele; Berretta, Luca; Bianucci, S; Boccali, Tommaso; Bosi, Filippo; Bracci, Fabrizio; Castaldi, Rino; Ceccanti, Marco; Cecchi, Roberto; Cerri, Claudio; Cucoanes, Andi Sebastian; Dell'Orso, Roberto; Dobur, Didar; Dutta, Suchandra; Giassi, Alessandro; Giusti, Simone; Kartashov, Dmitry; Kraan, Aafke; Lomtadze, Teimuraz; Lungu, George-Adrian; Magazzu, Guido; Mammini, Paolo; Mariani, Filippo; Martinelli, Giovanni; Moggi, Andrea; Palla, Fabrizio; Palmonari, Francesco; Petragnani, Giulio; Profeti, Alessandro; Raffaelli, Fabrizio; Rizzi, Domenico; Sanguinetti, Giulio; Sarkar, Subir; Sentenac, Daniel; Serban, Alin Titus; Slav, Adrian; Soldani, A; Spagnolo, Paolo; Tenchini, Roberto; Tolaini, Sergio; Venturi, Andrea; Verdini, Piero Giorgio; Vos, Marcel; Zaccarelli, Luciano; Avanzini, Carlo; Basti, Andrea; Benucci, Leonardo; Bocci, Andrea; Cazzola, Ugo; Fiori, Francesco; Linari, Stefano; Massa, Maurizio; Messineo, Alberto; Segneri, Gabriele; Tonelli, Guido; Azzurri, Paolo; Bernardini, Jacopo; Borrello, Laura; Calzolari, Federico; Foa, Lorenzo; Gennai, Simone; Ligabue, Franco; Petrucciani, Giovanni; Rizzi, Andrea; Yang, Zong-Chang; Benotto, Franco; Demaria, Natale; Dumitrache, Floarea; Farano, R; Borgia, Maria Assunta; Castello, Roberto; Costa, Marco; Migliore, Ernesto; Romero, Alessandra; Abbaneo, Duccio; Abbas, M; Ahmed, Ijaz; Akhtar, I; Albert, Eric; Bloch, Christoph; Breuker, Horst; Butt, Shahid Aleem; Buchmuller, Oliver; Cattai, Ariella; Delaere, Christophe; Delattre, Michel; Edera, Laura Maria; Engstrom, Pauli; Eppard, Michael; Gateau, Maryline; Gill, Karl; Giolo-Nicollerat, Anne-Sylvie; Grabit, Robert; Honma, Alan; Huhtinen, Mika; Kloukinas, Kostas; Kortesmaa, Jarmo; Kottelat, Luc-Joseph; Kuronen, Auli; Leonardo, Nuno; Ljuslin, Christer; Mannelli, Marcello; Masetti, Lorenzo; Marchioro, Alessandro; Mersi, Stefano; Michal, Sebastien; Mirabito, Laurent; Muffat-Joly, Jeannine; Onnela, Antti; Paillard, Christian; Pal, Imre; Pernot, Jean-Francois; Petagna, Paolo; Petit, Patrick; Piccut, C; Pioppi, Michele; Postema, Hans; Ranieri, Riccardo; Ricci, Daniel; Rolandi, Gigi; Ronga, Frederic Jean; Sigaud, Christophe; Syed, A; Siegrist, Patrice; Tropea, Paola; Troska, Jan; Tsirou, Andromachi; Vander Donckt, Muriel; Vasey, François; Alagoz, Enver; Amsler, Claude; Chiochia, Vincenzo; Regenfus, Christian; Robmann, Peter; Rochet, Jacky; Rommerskirchen, Tanja; Schmidt, Alexander; Steiner, Stefan; Wilke, Lotte; Church, Ivan; Cole, Joanne; Coughlan, John A; Gay, Arnaud; Taghavi, S; Tomalin, Ian R; Bainbridge, Robert; Cripps, Nicholas; Fulcher, Jonathan; Hall, Geoffrey; Noy, Matthew; Pesaresi, Mark; Radicci, Valeria; Raymond, David Mark; Sharp, Peter; Stoye, Markus; Wingham, Matthew; Zorba, Osman; Goitom, Israel; Hobson, Peter R; Reid, Ivan; Teodorescu, Liliana; Hanson, Gail; Jeng, Geng-Yuan; Liu, Haidong; Pasztor, Gabriella; Satpathy, Asish; Stringer, Robert; Mangano, Boris; Affolder, K; Affolder, T; Allen, Andrea; Barge, Derek; Burke, Samuel; Callahan, D; Campagnari, Claudio; Crook, A; D'Alfonso, Mariarosaria; Dietch, J; Garberson, Jeffrey; Hale, David; Incandela, H; Incandela, Joe; Jaditz, Stephen; Kalavase, Puneeth; Kreyer, Steven Lawrence; Kyre, Susanne; Lamb, James; Mc Guinness, C; Mills, C; Nguyen, Harold; Nikolic, Milan; Lowette, Steven; Rebassoo, Finn; Ribnik, Jacob; Richman, Jeffrey; Rubinstein, Noah; Sanhueza, S; Shah, Yousaf Syed; Simms, L; Staszak, D; Stoner, J; Stuart, David; Swain, Sanjay Kumar; Vlimant, Jean-Roch; White, Dean; Ulmer, Keith; Wagner, Stephen Robert; Bagby, Linda; Bhat, Pushpalatha C; Burkett, Kevin; Cihangir, Selcuk; Gutsche, Oliver; Jensen, Hans; Johnson, Mark; Luzhetskiy, Nikolay; Mason, David; Miao, Ting; Moccia, Stefano; Noeding, Carsten; Ronzhin, Anatoly; Skup, Ewa; Spalding, William J; Spiegel, Leonard; Tkaczyk, Slawek; Yumiceva, Francisco; Zatserklyaniy, Andriy; Zerev, E; Anghel, Ioana Maria; Bazterra, Victor Eduardo; Gerber, Cecilia Elena; Khalatian, S; Shabalina, Elizaveta; Baringer, Philip; Bean, Alice; Chen, Jie; Hinchey, Carl Louis; Martin, Christophe; Moulik, Tania; Robinson, Richard; Gritsan, Andrei; Lae, Chung Khim; Tran, Nhan Viet; Everaerts, Pieter; Hahn, Kristan Allan; Harris, Philip; Nahn, Steve; Rudolph, Matthew; Sung, Kevin; Betchart, Burton; Demina, Regina; Gotra, Yury; Korjenevski, Sergey; Miner, Daniel Carl; Orbaker, Douglas; Christofek, Leonard; Hooper, Ryan; Landsberg, Greg; Nguyen, Duong; Narain, Meenakshi; Speer, Thomas; Tsang, Ka Vang

    2009-01-01

    In March 2007 the assembly of the Silicon Strip Tracker was completed at the Tracker Integration Facility at CERN. Nearly 15% of the detector was instrumented using cables, fiber optics, power supplies, and electronics intended for the operation at the LHC. A local chiller was used to circulate the coolant for low temperature operation. In order to understand the efficiency and alignment of the strip tracker modules, a cosmic ray trigger was implemented. From March through July 4.5 million triggers were recorded. This period, referred to as the Sector Test, provided practical experience with the operation of the Tracker, especially safety, data acquisition, power, and cooling systems. This paper describes the performance of the strip system during the Sector Test, which consisted of five distinct periods defined by the coolant temperature. Significant emphasis is placed on comparisons between the data and results from Monte Carlo studies.

  3. Performance studies of the CMS Strip Tracker before installation

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; et al.

    2009-06-01

    In March 2007 the assembly of the Silicon Strip Tracker was completed at the Tracker Integration Facility at CERN. Nearly 15% of the detector was instrumented using cables, fiber optics, power supplies, and electronics intended for the operation at the LHC. A local chiller was used to circulate the coolant for low temperature operation. In order to understand the efficiency and alignment of the strip tracker modules, a cosmic ray trigger was implemented. From March through July 4.5 million triggers were recorded. This period, referred to as the Sector Test, provided practical experience with the operation of the Tracker, especially safety, data acquisition, power, and cooling systems. This paper describes the performance of the strip system during the Sector Test, which consisted of five distinct periods defined by the coolant temperature. Significant emphasis is placed on comparisons between the data and results from Monte Carlo studies.

  4. Data acquisition software for the CMS strip tracker

    CERN Document Server

    Bainbridge, R; Bel, S; Cole, J; Cripps, N; Delaere, C; Jesus, A C A; Drouhin, F; Fulcher, J; Giassi, A; Gill, K; Giordano, D; Gross, L; Hahn, K; Mersi, S; Mirabito, L; Nikolic, M; Radicci, V; Tkaczyk, S; Wingham, M

    2008-01-01

    The CMS silicon strip tracker, providing a sensitive area of approximately 200 m2 and comprising 10 million readout channels, has recently been completed at the tracker integration facility at CERN. The strip tracker community is currently working to develop and integrate the online and offline software frameworks, known as XDAQ and CMSSW respectively, for the purposes of data acquisition and detector commissioning and monitoring. Recent developments have seen the integration of many new services and tools within the online data acquisition system, such as event building, online distributed analysis, an online monitoring framework, and data storage management. We review the various software components that comprise the strip tracker data acquisition system, the software architectures used for stand-alone and global data-taking modes. Our experiences in commissioning and operating one of the largest ever silicon micro-strip tracking systems are also reviewed.

  5. HETDEX tracker control system design and implementation

    Science.gov (United States)

    Beno, Joseph H.; Hayes, Richard; Leck, Ron; Penney, Charles; Soukup, Ian

    2012-09-01

    To enable the Hobby-Eberly Telescope Dark Energy Experiment, The University of Texas at Austin Center for Electromechanics and McDonald Observatory developed a precision tracker and control system - an 18,000 kg robot to position a 3,100 kg payload within 10 microns of a desired dynamic track. Performance requirements to meet science needs and safety requirements that emerged from detailed Failure Modes and Effects Analysis resulted in a system of 13 precision controlled actuators and 100 additional analog and digital devices (primarily sensors and safety limit switches). Due to this complexity, demanding accuracy requirements, and stringent safety requirements, two independent control systems were developed. First, a versatile and easily configurable centralized control system that links with modeling and simulation tools during the hardware and software design process was deemed essential for normal operation including motion control. A second, parallel, control system, the Hardware Fault Controller (HFC) provides independent monitoring and fault control through a dedicated microcontroller to force a safe, controlled shutdown of the entire system in the event a fault is detected. Motion controls were developed in a Matlab-Simulink simulation environment, and coupled with dSPACE controller hardware. The dSPACE real-time operating system collects sensor information; motor commands are transmitted over a PROFIBUS network to servo amplifiers and drive motor status is received over the same network. To interface the dSPACE controller directly to absolute Heidenhain sensors with EnDat 2.2 protocol, a custom communication board was developed. This paper covers details of operational control software, the HFC, algorithms, tuning, debugging, testing, and lessons learned.

  6. Design of a Solar Tracker System for PV Power Plants

    OpenAIRE

    Tiberiu Tudorache; Liviu Kreindler

    2010-01-01

    This paper deals with the design and execution of a solar tracker systemdedicated to the PV conversion panels. The proposed single axis solar tracker deviceensures the optimization of the conversion of solar energy into electricity by properlyorienting the PV panel in accordance with the real position of the sun. The operation of theexperimental model of the device is based on a DC motor intelligently controlled by adedicated drive unit that moves a mini PV panel according to the signals rece...

  7. Expected performance of the ATLAS Inner Tracker upgrade

    CERN Document Server

    Viel, Simon; The ATLAS collaboration

    2016-01-01

    The design of the ATLAS Inner Tracker upgrade is underway. This tracking detector, consisting of silicon pixel and strip modules, will replace the current ATLAS Inner Detector to reconstruct tracks from charged particles produced at the very high collision rate expected from the High-Luminosity Large Hadron Collider. The latest Inner Tracker designs considered, and the most recent expected performance results from simulation are presented.

  8. Launch strategy for a GPS-based package tracker product

    OpenAIRE

    Biermann, Jürgen

    2006-01-01

    The objective of this paper is to present a recommendation for a launch strategy for a new Package Tracker Product based on enhanced GPS location technology for a GPS software company, Guardian Mobile Monitoring Systems. We will first give an overview of Global Positioning System (GPS) technology and its more recent advancements and explain the potential for a package tracker product. Secondly, we will examine possible target market segments. Thirdly, we will perform an internal analysis of G...

  9. A Hardware Fast Tracker for the ATLAS Trigger: The Fast TracKer (FTK) Project.

    CERN Document Server

    Asbah, Nedaa; The ATLAS collaboration

    2015-01-01

    The trigger system of the ATLAS experiment is designed to reduce the event rate from the LHC nominal bunch crossing at 40 MHz to about 1 kHz, at the design luminosity of 10^{34} cm^{-2} s{-1}. After a successful period of data taking from 2010 to early 2013, the LHC is restarting in 2015 with much higher instantaneous luminosity and this will increase the load on High Level Trigger system, the second stage of the selection based on software algorithms. More sophisticated algorithms will be needed to achieve higher background rejection while maintaining good efficiency for interesting physics signals. The Fast TracKer is part of the ATLAS trigger upgrade project; it is a hardware processor that will provide, at every level-1 accept (100 kHz) and within 100 microseconds, full tracking information for tracks with momentum as low as 1 GeV. Providing fast extensive access to tracking information, with resolution comparable to the offline reconstruction, the Fast Tracker will for example help the High Level Trigger...

  10. Multi-expert tracking algorithm based on improved compressive tracker

    Science.gov (United States)

    Feng, Yachun; Zhang, Hong; Yuan, Ding

    2015-12-01

    Object tracking is a challenging task in computer vision. Most state-of-the-art methods maintain an object model and update the object model by using new examples obtained incoming frames in order to deal with the variation in the appearance. It will inevitably introduce the model drift problem into the object model updating frame-by-frame without any censorship mechanism. In this paper, we adopt a multi-expert tracking framework, which is able to correct the effect of bad updates after they happened such as the bad updates caused by the severe occlusion. Hence, the proposed framework exactly has the ability which a robust tracking method should process. The expert ensemble is constructed of a base tracker and its formal snapshot. The tracking result is produced by the current tracker that is selected by means of a simple loss function. We adopt an improved compressive tracker as the base tracker in our work and modify it to fit the multi-expert framework. The proposed multi-expert tracking algorithm significantly improves the robustness of the base tracker, especially in the scenes with frequent occlusions and illumination variations. Experiments on challenging video sequences with comparisons to several state-of-the-art trackers demonstrate the effectiveness of our method and our tracking algorithm can run at real-time.

  11. Autonomic disturbances in narcolepsy.

    Science.gov (United States)

    Plazzi, Giuseppe; Moghadam, Keivan Kaveh; Maggi, Leonardo Serra; Donadio, Vincenzo; Vetrugno, Roberto; Liguori, Rocco; Zoccoli, Giovanna; Poli, Francesca; Pizza, Fabio; Pagotto, Uberto; Ferri, Raffaele

    2011-06-01

    Narcolepsy is a clinical condition characterized mainly by excessive sleepiness and cataplexy. Hypnagogic hallucinations and sleep paralysis complete the narcoleptic tetrad; disrupted night sleep, automatic behaviors and weight gain are also usual complaints. Different studies focus on autonomic changes or dysfunctions among narcoleptic patients, such as pupillary abnormalities, fainting spells, erectile dysfunction, night sweats, gastric problems, low body temperature, systemic hypotension, dry mouth, heart palpitations, headache and extremities dysthermia. Even if many studies lack sufficient standardization or their results have not been replicated, a non-secondary involvement of the autonomic nervous system in narcolepsy is strongly suggested, mainly by metabolic and cardiovascular findings. Furthermore, the recent discovery of a high risk for overweight and for metabolic syndrome in narcoleptic patients represents an important warning for clinicians in order to monitor and follow them up for their autonomic functions. We review here studies on autonomic functions and clinical disturbances in narcoleptic patients, trying to shed light on the possible contribute of alterations of the hypocretin system in autonomic pathophysiology.

  12. Architecture of autonomous systems

    Science.gov (United States)

    Dikshit, Piyush; Guimaraes, Katia; Ramamurthy, Maya; Agrawala, Ashok; Larsen, Ronald L.

    1989-01-01

    Automation of Space Station functions and activities, particularly those involving robotic capabilities with interactive or supervisory human control, is a complex, multi-disciplinary systems design problem. A wide variety of applications using autonomous control can be found in the literature, but none of them seem to address the problem in general. All of them are designed with a specific application in mind. In this report, an abstract model is described which unifies the key concepts underlying the design of automated systems such as those studied by the aerospace contractors. The model has been kept as general as possible. The attempt is to capture all the key components of autonomous systems. With a little effort, it should be possible to map the functions of any specific autonomous system application to the model presented here.

  13. Exercise and autonomic function.

    Science.gov (United States)

    Goldsmith, R L; Bloomfield, D M; Rosenwinkel, E T

    2000-03-01

    The complex interplay between the dichotomous subdivisions of the autonomic nervous system establishes and maintains a delicately tuned homeostasis in spite of an ever-changing environment. Aerobic exercise training can increase activity of the parasympathetic nervous system and decrease sympathetic activity. Conversely, it is well-documented that cardiac disease is often characterized by attenuated parasympathetic activity and heightened sympathetic tone. A correlation between autonomic disequilibrium and disease has led to the hypothesis that exercise training, as a therapy that restores the autonomic nervous system towards normal function, may be associated with, and possibly responsible for, outcome improvements in various populations. This is merely one of the many benefits that is conferred by chronic exercise training and reviewed in this issue. PMID:10758814

  14. Technical Training Seminar: Laser Trackers: the Local Positioning Technology (LPT)

    CERN Multimedia

    Davide Vitè

    2005-01-01

    Friday 20 May from 10:00 to 16:00, Training Centre (bldg. 593) Laser Trackers: the Local Positioning Technology (LPT) Simon Moser, Michael Lettau, Achim Lupus, Niklaus Suter, Leica GEOSYSTEMS AG, Switzerland Laser trackers are used at CERN for different applications within the LHC Project. Leica Geosystems AG have been developing during the last four years the revolutionary Local Positioning Technology (LPT). Laser trackers are increasingly used to ensure accuracy of large fabrications, and alignment in the final assembly process. Competing portable Coordinate Measuring Machines (CMM) with articulated arms require a frequent repositioning, known to lead to a loss of accuracy and efficiency. Leica Geosystems developed armless solutions, the T-Probe and T-Scan, for use with its laser trackers. The combination of the tracker technology with photogrammetry is the base of LPT, enabling real time measurements with free hand-held devices, such as the T-Probe and T-Scan. T-Probe and T-Scan overcome the proble...

  15. Software alignment of the LHCb Outer Tracker chambers

    International Nuclear Information System (INIS)

    This work presents an alignment algorithm that was developed to precisely determine the positions of the LHCb Outer Tracker detector elements. The algorithm is based on the reconstruction of tracks and exploits that misalignments of the detector change the residual between a measured hit and the reconstructed track. It considers different levels of granularities of the Outer Tracker geometry and fully accounts for correlations of all elements which are imposed by particle trajectories. In extensive tests, simulated shifts and rotations for different levels of the detector granularity have been used as input to the track reconstruction and alignment procedure. With about 260 000 tracks the misalignments are recovered with a statistical precision of O(10 - 100 μm) for the translational degrees of freedom and of O(10-2 - 10-1 mrad) for rotations. A study has been performed to determine the impact of Outer Tracker misalignments on the performance of the track reconstruction algorithms. It shows that the achieved statistical precision does not decrease the track reconstruction performance in a significant way. During the commissioning of the LHCb detector, cosmic ray muon events have been collected. The events have been analysed and used for the first alignment of the 216 Outer Tracker modules. The module positions have been determined within ∝ 90 μm. The developed track based alignment algorithm has demonstrated its reliability and is one of the core algorithms which are used for the precise determination of the positions of the LHCb Outer Tracker elements. (orig.)

  16. Software alignment of the LHCb Outer Tracker chambers

    Energy Technology Data Exchange (ETDEWEB)

    Deissenroth, Marc

    2010-04-21

    This work presents an alignment algorithm that was developed to precisely determine the positions of the LHCb Outer Tracker detector elements. The algorithm is based on the reconstruction of tracks and exploits that misalignments of the detector change the residual between a measured hit and the reconstructed track. It considers different levels of granularities of the Outer Tracker geometry and fully accounts for correlations of all elements which are imposed by particle trajectories. In extensive tests, simulated shifts and rotations for different levels of the detector granularity have been used as input to the track reconstruction and alignment procedure. With about 260 000 tracks the misalignments are recovered with a statistical precision of O(10 - 100 {mu}m) for the translational degrees of freedom and of O(10{sup -2} - 10{sup -1} mrad) for rotations. A study has been performed to determine the impact of Outer Tracker misalignments on the performance of the track reconstruction algorithms. It shows that the achieved statistical precision does not decrease the track reconstruction performance in a significant way. During the commissioning of the LHCb detector, cosmic ray muon events have been collected. The events have been analysed and used for the first alignment of the 216 Outer Tracker modules. The module positions have been determined within {proportional_to} 90 {mu}m. The developed track based alignment algorithm has demonstrated its reliability and is one of the core algorithms which are used for the precise determination of the positions of the LHCb Outer Tracker elements. (orig.)

  17. Advances in RGB and RGBD Generic Object Trackers

    KAUST Repository

    Bibi, Adel

    2016-04-01

    Visual object tracking is a classical and very popular problem in computer vision with a plethora of applications such as vehicle navigation, human computer interface, human motion analysis, surveillance, auto-control systems and many more. Given the initial state of a target in the first frame, the goal of tracking is to predict states of the target over time where the states describe a bounding box covering the target. Despite numerous object tracking methods that have been proposed in recent years [1-4], most of these trackers suffer a degradation in performance mainly because of several challenges that include illumination changes, motion blur, complex motion, out of plane rotation, and partial or full occlusion, while occlusion is usually the most contributing factor in degrading the majority of trackers, if not all of them. This thesis is devoted to the advancement of generic object trackers tackling different challenges through different proposed methods. The work presented propose four new state-of-the-art trackers. One of which is 3D based tracker in a particle filter framework where both synchronization and registration of RGB and depth streams are adjusted automatically, and three works in correlation filters that achieve state-of-the-art performance in terms of accuracy while maintaining reasonable speeds.

  18. Autonomous electrochromic assembly

    Science.gov (United States)

    Berland, Brian Spencer; Lanning, Bruce Roy; Stowell, Jr., Michael Wayne

    2015-03-10

    This disclosure describes system and methods for creating an autonomous electrochromic assembly, and systems and methods for use of the autonomous electrochromic assembly in combination with a window. Embodiments described herein include an electrochromic assembly that has an electrochromic device, an energy storage device, an energy collection device, and an electrochromic controller device. These devices may be combined into a unitary electrochromic insert assembly. The electrochromic assembly may have the capability of generating power sufficient to operate and control an electrochromic device. This control may occur through the application of a voltage to an electrochromic device to change its opacity state. The electrochromic assembly may be used in combination with a window.

  19. MEVSIM: A Monte Carlo Event Generator for STAR

    OpenAIRE

    Ray, R. L.; Longacre, R. S.

    2000-01-01

    A fast, simple to use Monte Carlo based event generator is presented which is intended to facilitate simulation studies and the development of analysis software for the Solenoidal Tracker at RHIC (Relativistic Heavy Ion Collider) (STAR) experiment at the Brookhaven National Laboratory (BNL). This new event generator provides a fast, convenient means for producing large numbers of uncorrelated A+A collision events which can be used for a variety of applications in STAR, including quality assur...

  20. Overview of recent results from the STAR experiment

    OpenAIRE

    Mustafa, Mustafa

    2015-01-01

    The Solenoidal Tracker at RHIC (STAR) experiment utilizes its excellent mid-rapidity tracking and particle identification capabilities to study the emergent properties of Quantum Chromodynamics (QCD). The STAR heavy-ion program at vanishingly small baryon density is aimed to address questions about the quantitative properties of the strongly-interacting Quark Gluon Plasma (QGP) matter created in high energy collisions ($\\eta/s$, $\\hat{q}$, chirality, transport parameters, heavy quark diffusio...

  1. Open charm measurement with HFT at STAR

    OpenAIRE

    Kapitan, Jan; Collaboration, for the STAR

    2008-01-01

    Thermalization is one of the key questions in understanding the matter created in Au+Au collisions at RHIC. Heavy-flavor quark collectivity could be used to indicate the degree of thermalization of the light-flavor quarks. Heavy quark energy loss could give important information on color charge density of the medium. Direct reconstruction of open charm hadrons is essential for these measurements. The Heavy Flavor Tracker (HFT) is a proposed upgrade of the STAR experiment. Full GEANT simulatio...

  2. EU Climate Policy Tracker 2011. Main report

    Energy Technology Data Exchange (ETDEWEB)

    Hoehne, N.; Geurts, F.; Teckenburg, E.; Blok, K.; Becker, D. [Ecofys, Utrecht (Netherlands)

    2011-11-15

    Limiting the rise in the average global temperature to 2C has been the EU goal since 1996, and in December 2010 the UN recognised the need to consider a 1.5C limit. Avoiding overshooting these levels will require massive emissions reductions - in the order of 80-95% for industrialised countries, like those in the EU. The next ten years are crucial in establishing whether society will be able to make this transition, or whether temperature increase limits will be irreversibly missed. Last year, the European Union Climate Policy Tracker (EU CPT) investigated each member state's implementation of policy and legislation, and rated their progress towards a 2050 vision of deep decarbonisation using renewable energy. The uniquely developed rating scheme, modelled on appliance efficiency labels (A-G), gave an indication of how member states were doing compared to a 'low-carbon policy package'. The average score was an 'E', indicating that the level of effort needed to treble, to be on a pace to reach the 2050 vision. However, aggregating best practices across sectors and countries doubled the score - meaning that the tools are already at hand for major improvements across Europe. This report builds on last year's EU CPT by giving an update on action in member states, and an indicative trend in the rating, as well as adding a new section on EU policy. The addition of an EU section is appropriate, with the Commission having produced a roadmap on a low-carbon economy by 2050, a transport white paper, and with another roadmap for 2050 focused on energy anticipated by the end of 2011. This report seeks to answer the question of whether these and other related initiatives are sufficient to help Europe reach its low-carbon goals. When interpreting the results of this report, it is important to understand that the goal underlying the vision here is not the same as the one in the European Commission's 'low-carbon economy' roadmap

  3. PRIMUS: autonomous driving robot for military applications

    Science.gov (United States)

    Schwartz, Ingo

    2000-07-01

    This article describes the government experimental program PRIMUS (PRogram of Intelligent Mobile Unmanned Systems) and the achieved results of phase C demonstrated in summer 1999 on a military prooving ground. In this program there shall be shown the autonomous driving on an unmanned robot in open terrain. The most possible degree of autonomy shall be reached with today's technology to get a platform for different missions. The goal is to release the soldier from high dangerous tasks, to increase the performance and to come to a reduction of personnel and costs with unmanned systems. In phase C of the program two small tracked vehicles (Digitized Wiesel 2, airtransportable by CH53) are used. One as a robot vehicle the other as a command & control system. The Wiesel 2 is configured as a drive by wire-system and therefore well suited for the adaption of control computers. The autonomous detection and avoidance of obstacles in unknown, not cooperative environment is the main task. For navigation and orientation a sensor package is integrated. To detect obstacles the scene in the driving corridor of the robot is scanned 4 times per second by a 3D- Range image camera (LADAR). The measured 3D-range image is converted into a 2D-obstacle map and used as input for calculation of an obstacle free path. The combination of local navigation (obstacle avoidance) and global navigation leads to a collission free driving in open terrain to a predefined goal point with a velocity of up to 25km/h. A contour tracker with a TV-camera as sensor is also implemented which allows to follow contours (e.g. edge of a meadow) or to drive on paved or unpaved roads with a velocity up to 50km/h. In addition to these autonomous driving modes the operator in the command & control station can drive the robot by remote control. All the functions were successfully demonstrated in the summer 1999 on a military prooving ground. During a mission example the robot vehicle covered a distance of several

  4. Overview of the Autonomic Nervous System

    Science.gov (United States)

    ... reversible or progressive. Anatomy of the autonomic nervous system The autonomic nervous system is the part of ... they connect with. Function of the autonomic nervous system The autonomic nervous system controls internal body processes ...

  5. Data Quality Monitoring for the CMS Silicon Tracker

    CERN Document Server

    Dutta, S; Mennea, Maria Santa; Zito, G

    2006-01-01

    The CMS silicon tracker, consisting of about 17,000 detector modules and divided into micro-strip and pixel sensors, will be the largest silicon tracker ever realized for high energy physics experiments. The detector performance will be monitored using applications based on the CMS Data Quality Monitoring\\,(DQM) framework and running on the High-Level Trigger Farm as well as local DAQ systems. The monitorable quantities of this large number of modules are divided into hierarchical structures reflecting the detector sections. In addition, they are organized into structures corresponding to the levels of data processing. The information produced are delivered to client applications according to their subscription requests. The client applications summarize and visualize the quantities received. We describe here the functionalities of the CMS tracker DQM applications and report preliminary performance tests.

  6. The Reconstruction Software for the Muon Ionization Cooling Experiment Trackers

    Energy Technology Data Exchange (ETDEWEB)

    Dobbs, A. [Imperial Coll., London; Long, K. [Imperial Coll., London; Santos, E. [Imperial Coll., London; Adey, D. [Fermilab; Hanlet, P. [Fermilab; Heidt, C. [UC, Riverside

    2014-01-01

    The international Muon Ionisation Cooling Experiment (MICE) is designed to demonstrate the principle of muon ionization cooling, for application to a future Neutrino Factory or Muon Collider. In order to measure the change in emittance, MICE is equipped with a pair of high precision scintillating fibre trackers. The trackers are required to measure a 10% change in emittance to 1% accuracy (giving an overall precision of 0.1%). This paper describes the tracker reconstruction software, as a part of the overall MICE software framework, MAUS. Channel clustering is described, proceeding to the formation of space-points, which are then associated with particle tracks using pattern recognition algorithms. Finally a full custom Kalman track fit is performed, to account for energy loss and multiple scattering. Exemplar results are shown for Monte Carlo data.

  7. A fast hardware tracker for the ATLAS trigger system

    International Nuclear Information System (INIS)

    The Fast Tracker (FTK) processor is an approved ATLAS upgrade that will reconstruct tracks using the full silicon tracker at Level-1 rate (up to 100 KHz). FTK uses a completely parallel approach to read the silicon tracker information, execute the pattern matching and reconstruct the tracks. This approach, according to detailed simulation results, allows full tracking with nearly offline resolution within an execution time of 100μs. A central component of the system is the associative memories (AM); these special devices reduce the pattern matching combinatoric problem, providing identification of coarse resolution track candidates. The system consists of a pipeline of several components with the goal to organize and filter the data for the AM, then to reconstruct and filter the final tracks. This document presents an overview of the system and reports the status of the different elements of the system

  8. ADAM: ADaptive Autonomous Machine

    NARCIS (Netherlands)

    Oosten, van Daan C.; Nijenhuis, Lucas F.J.; Bakkers, André W.P.; Vervoort, Wiek A.

    1996-01-01

    This paper describes a part of the development of an adaptive autonomous machine that is able to move in an unknown world extract knowledge out of the perceived data, has the possibility to reason, and finally has the capability to exchange experiences and knowledge with other agents. The agent is n

  9. Autonomous data transmission apparatus

    Science.gov (United States)

    Kotlyar, Oleg M.

    1997-01-01

    A autonomous borehole data transmission apparatus for transmitting measurement data from measuring instruments at the downhole end of a drill string by generating pressure pulses utilizing a transducer longitudinally responsive to magnetic field pulses caused by electrical pulses corresponding to the measured downhole parameters.

  10. Stars and Star Myths.

    Science.gov (United States)

    Eason, Oliver

    Myths and tales from around the world about constellations and facts about stars in the constellations are presented. Most of the stories are from Greek and Roman mythology; however, a few Chinese, Japanese, Polynesian, Arabian, Jewish, and American Indian tales are also included. Following an introduction, myths are presented for the following 32…

  11. Software Architecture for Autonomous Spacecraft

    Science.gov (United States)

    Shih, Jimmy S.

    1997-01-01

    The thesis objective is to design an autonomous spacecraft architecture to perform both deliberative and reactive behaviors. The Autonomous Small Planet In-Situ Reaction to Events (ASPIRE) project uses the architecture to integrate several autonomous technologies for a comet orbiter mission.

  12. Design of a Solar Tracker System for PV Power Plants

    Directory of Open Access Journals (Sweden)

    Tiberiu Tudorache

    2010-04-01

    Full Text Available This paper deals with the design and execution of a solar tracker systemdedicated to the PV conversion panels. The proposed single axis solar tracker deviceensures the optimization of the conversion of solar energy into electricity by properlyorienting the PV panel in accordance with the real position of the sun. The operation of theexperimental model of the device is based on a DC motor intelligently controlled by adedicated drive unit that moves a mini PV panel according to the signals received from twosimple but efficient light sensors. The performance and characteristics of the solar trackerare experimentally analyzed.

  13. Characterization of the Ecosole HCPV tracker and single module inverter

    Science.gov (United States)

    Carpanelli, Maurizio; Borelli, Gianni; Verdilio, Daniele; De Nardis, Davide; Migali, Fabrizio; Cancro, Carmine; Graditi, Giorgio

    2015-09-01

    BECAR, the Beghelli group's R&D company, is leading ECOSOLE (Elevated COncentration SOlar Energy), one of the largest European Demonstration projects in solar photovoltaic. ECOSOLE, started in 2012, is focused on the study, design, and realization of new HCPV generator made of high efficiency PV modules equipped with SoG (Silicone on Glass) fresnel lenses and III-V solar cells, and a low cost matched solar tracker with distributed inverters approach. The project also regards the study and demonstration of new high throughput methods for the industrial large scale productions, at very low manufacturing costs. This work reports the description of the characterization of the tracker and single module.

  14. TRACKER INSERTED INTO YB0 & HEAVY LOWERING COMPLETED

    CERN Multimedia

          The Tracker travelled very smoothly from Meyrin to Point 5 during the early hours of December 13th. Lowered later the same day, insertion was completed 18th December. The intense campaign of Tracker connections, involving 980 pipes, 2330 cables and 3623 fibre ribbons, has since begun and is making good progress. The final large element of CMS YE-1 was lowered gently into the cavern on January 22nd. This marks the end of fourteen months of heavy lowering operations.  

  15. Environmental testing results over a tracker drive train

    Science.gov (United States)

    Martínez, María; Calvo-Parra, Gustavo; Gil, Eduardo; de la Rubia, Oscar; Hillebrand, Mario; Rubio, Francisca; Aipperspach, Wolfgang; Gombert, Andreas

    2014-09-01

    Environmental testing following the draft of the IEC62817 standard has been carried out at ISFOC using a Soitec Solar tracker drive. The objective of this work is twofold; first to assure that the tracker design can perform under varying conditions and survive under extreme conditions and secondly to test the viability and usefulness of the tests described in the standard. After some changes in the device under test (specifically, gear-box oil) the drive system produced satisfactory results, assuring its performance under operational temperatures. Therefore, this work has demonstrated that the tests described in the standard are useful for detecting early failures.

  16. Charge determination of nuclei with the AMS-02 silicon tracker

    CERN Document Server

    Alpat, B; Azzarello, P; Battiston, R; Bene, P; Bertucci, B; Bizzaglia, S; Bizzarri, M; Blasko, S; Bourquin, M; Bouvier, P; Burger, W J; Capell, M; Cecchi, C; Chang, Y H; Cortina, E; Dinu, N; Esposito, G; Fiandrini, E; Haas, D; Hakobyan, H; Ionica, M; Ionica, R; Kounine, A; Koutsenko, V F; Lebedev, A; Lechanoine-Leluc, C; Lin, C H; Masciocchi, F; Menichelli, M; Natale, S; Paniccia, M; Papi, A; Pauluzzi, M; Perrin, E; Pohl, M; Rapin, D; Richeux, J P; Wallraff, W; Willenbrock, M; Zuccon, P

    2005-01-01

    The silicon tracker of the AMS-02 detector measures the trajectory in three dimensions of electrons, protons and nuclei to high precision in a dipole magnetic field and thus measures their rigidity (momentum over charge) and the sign of their charge. In addition, it measures the specific energy loss of charged particles to determine the charge magnitude. Ladders from the AMS-02 tracker have been exposed to ion beams at CERN and GSI to study their response to nuclei from helium up to the iron group. The longest ladder, 72 multiplied by 496mm2, verified in the tests contains 12 sensors. Good charge resolution is observed up to iron.

  17. Hybrid Design, Procurement and Testing for the LHCb Silicon Tracker

    CERN Document Server

    Bay, A; Frei, R; Jiménez-Otero, S; Perrin, A; Tran, MT; Van Hunen, J J; Vervink, K; Vollhardt, A; Agari, M; Bauer, C; Blouw, J; Hofmann, W; Knöpfle, K T; Löchner, S; Schmelling, M; Schwingenheuer, B; Smale, N J; Adeva, B; Esperante-Pereira, D; Lois, C; Vázquez, P; Lehner, F; Bernhard, R P; Bernet, R; Gassner, J; Köstner, S; Needham, M; Steinkamp, O; Straumann, U; Volyanskyy, D; Voss, H; Wenger, A

    2005-01-01

    The Silicon Tracker of the LHCb experiment consists of four silicon detector stations positioned along the beam line of the experiment. The detector modules of each station are constructed from wide pitch silicon microstrip sensors. Located at the module's end, a polyimide hybrid is housing the front-end electronics. The assembly of the more than 600 hybrids has been outsourced to industry. We will report on the design and production status of the hybrids for the LHCb Silicon Tracker and describe the quality assurance tests. Particular emphasis is laid on the vendor qualifying and its impact on our hybrid design that we experienced during the prototyping phase.

  18. Latency and distortion of electromagnetic trackers for augmented reality systems

    CERN Document Server

    Himberg, Henry

    2014-01-01

    Augmented reality (AR) systems are often used to superimpose virtual objects or information on a scene to improve situational awareness. Delays in the display system or inaccurate registration of objects destroy the sense of immersion a user experiences when using AR systems. AC electromagnetic trackers are ideal for these applications when combined with head orientation prediction to compensate for display system delays. Unfortunately, these trackers do not perform well in environments that contain conductive or ferrous materials due to magnetic field distortion without expensive calibration

  19. Online Monitoring for the Silicon Tracker of the LHCb Experiment

    CERN Document Server

    Chiapolini, N

    While the LHCb exp eriment acquires data, the detector and the data quality are continuously monitored. The rst part of this thesis describ es a package that was develop ed for managing monitoring pages. This package is a sub detector indep endent to ol originally develop ed for the online monitoring system of the Silicon Tracker. In the second half of this thesis, metho des to calculate the common mo de subtracted noise in the Silicon Tracker are compared. Dierent p ossible adjustments are evaluated and p ossible improvements presented.

  20. Retroreflector field tracker. [noncontact optical position sensor for space application

    Science.gov (United States)

    Wargocki, F. E.; Ray, A. J.; Hall, G. E.

    1984-01-01

    An electrooptical position-measuring instrument, the Retroreflector Field Tracker or RFT, is described. It is part of the Dynamic Augmentation Experiment - a part of the payload of Space Shuttle flight 41-D in Summer 1984. The tracker measures and outputs the position of 23 reflective targets placed on a 32-m solar array to provide data for determination of the dynamics of the lightweight structure. The sensor uses a 256 x 256 pixel CID detector; the processor electronics include three Z-80 microprocessors. A pulsed laser diode illuminator is used.

  1. Environmental Tests of the Flight GLAST LAT Tracker Towers

    Energy Technology Data Exchange (ETDEWEB)

    Bagagli, R.; Baldini, L.; Bellazzini, R.; Barbiellini, G.; Belli, F.; Borden, T.; Brez, A.; Brigida, M.; Caliandro, G.A.; Cecchi, C.; Cohen-Tanugi, J.; Angelis, A.De; Drell, P.; Favuzzi, C.; Fusco, P.; Gargano, F.; Germani, S.; Giglietto, N.; Giordano, F.; Goodman, J.; Himel, T.

    2008-03-12

    The Gamma-ray Large Area Space telescope (GLAST) is a gamma-ray satellite scheduled for launch in 2008. Before the assembly of the Tracker subsystem of the Large Area Telescope (LAT) science instrument of GLAST, every component (tray) and module (tower) has been subjected to extensive ground testing required to ensure successful launch and on-orbit operation. This paper describes the sequence and results of the environmental tests performed on an engineering model and all the flight hardware of the GLAST LAT Tracker. Environmental tests include vibration testing, thermal cycles and thermal-vacuum cycles of every tray and tower as well as the verification of their electrical performance.

  2. Star Product and Star Exponential

    OpenAIRE

    Tomihisa, Toshio; Yoshioka, Akira

    2010-01-01

    Here we extend the star products by means of complex symmetric matrices. In this way we obtain a family of star products. Next we consider the star exponentials with respect to these star products, and finally we obtain several interesting identities.

  3. Catecholamines and diabetic autonomic neuropathy

    DEFF Research Database (Denmark)

    Hilsted, J

    1995-01-01

    In diabetic patients with autonomic neuropathy plasma noradrenaline concentration, used as an index of sympathetic nervous activity, is low. This decrease is, however, only found in patients with a long duration of diabetes with clinically severe autonomic neuropathy. This apparent insensitivity...... of plasma catecholamine measurements is not due to changes in the clearance of catecholamines in diabetic autonomic neuropathy. The physiological responses to infused adrenaline and to noradrenaline are enhanced, for noradrenaline mainly cardiovascular responses. Adrenoceptors (alpha and beta adrenoceptors......) are not altered in circulating blood cells in diabetic autonomic neuropathy. Thus, a generalized up-regulation of adrenoceptors does not occur in diabetic autonomic neuropathy....

  4. 次世代型スタートラッカの研究

    OpenAIRE

    Matsumoto, Shuichi; Suzuki, Hideto; Kawai, Hiroshi; 松本 秀一; 鈴木 秀人; 川井 洋志

    2006-01-01

    Scientific satellites have been utilizing first generation star trackers that have only star imaging function. Recent technological advances on computer enable second generation star trackers that have autonomous star identification and attitude estimation functions without any a priori information. Based on requirements of future satellite programs and technological trends of overseas, we have been studying 'Next Generation Star Tracker' which categorized in the second generation star tracke...

  5. Design of a sun tracker for the automatic measurement of spectral irradiance and construction of an irradiance database in the 330-1100 nm range

    Energy Technology Data Exchange (ETDEWEB)

    Canada, J.; Maj, A. [Departamento de Termodinamica Aplicada, Universidad Politecnica de Valencia, Camino de Vera, s/n. 46022 Valencia (Spain); Utrillas, M.P.; Martinez-Lozano, J.A.; Pedros, R.; Gomez-Amo, J.L. [Departamento de Fisica de la Tierra y Termodinamica, Facultat de Fisica, Universitat de Valencia, 46100 Burjassot (Valencia) (Spain)

    2007-10-15

    An automatic global and direct solar spectral irradiance system has been designed based on two LICOR spectro radiometers equipped with fibre optics and remote cosine sensors. To measure direct irradiance a sun tracker based on step motors has been developed. The whole system is autonomous and works continuously. From the measurements provided by this system a spectral irradiance database in the 330-1100 nm range has been created. This database contains normal direct and global horizontal irradiances as well as diffuse irradiance on a horizontal plane, together with total atmospheric optical thickness and aerosol optical depth. (author)

  6. Supporting Technical Debt Cataloging with TD-Tracker Tool

    Directory of Open Access Journals (Sweden)

    Lucas Borante Foganholi

    2015-01-01

    Full Text Available Technical debt (TD is an emergent area that has stimulated academic concern. Managers must have information about debt in order to balance time-to-market advantages and issues of TD. In addition, managers must have information about TD to plan payments. Development tasks such as designing, coding, and testing generate different sorts of TD, each one with specific information. Moreover, literature review pointed out a gap in identifying and accurately cataloging technical debt. It is possible to find tools that can identify technical debt, but there is not a described solution that supports cataloging all types of debt. This paper presents an approach to create an integrated catalog of technical debts from different software development tasks. The approach allows tabulating and managing TD properties in order to support managers in the decision process. It also allows managers to track TD. The approach is implemented by TD-Tracker tool, which can integrate different TD identification tools and import identified debts. We present integrations between TD-Tracker and two external tools, used to identify potential technical debts. As part of the approach, we describe how to map the relationship between TD-Tracker and the external tools. We also show how to manage external information within TD-Tracker.

  7. Parallax error in the monocular head-mounted eye trackers

    DEFF Research Database (Denmark)

    Mardanbeigi, Diako; Witzner Hansen, Dan

    2012-01-01

    This paper investigates the parallax error, which is a common problem of many video-based monocular mobile gaze trackers. The parallax error is defined and described using the epipolar geometry in a stereo camera setup. The main parameters that change the error are introduced and it is shown how ...

  8. ATLAS Transition Radiation Tracker test-beam results

    CERN Document Server

    Åkesson, T; Baker, K; Baron, S; Benjamin, D; Bertelsen, H; Bondarenko, V; Bychkov, V; Callahan, J; Capéans-Garrido, M; Cardiel-Sas, L; Catinaccio, A; Cetin, S A; Cwetanski, Peter; Dam, M; Danielsson, H; Dittus, F; Dolgoshein, B A; Dressnandt, N; Driouichi, C; Ebenstein, W L; Eerola, Paule Anna Mari; Farthouat, Philippe; Fedin, O; Froidevaux, D; Gagnon, P; Grichkevitch, Y; Grigalashvili, N S; Hajduk, Z; Hansen, P; Kayumov, F; Keener, P T; Kekelidze, G D; Khristatchev, A; Konovalov, S; Koudine, L; Kovalenko, S; Kowalski, T; Kramarenko, V A; Krüger, K; Laritchev, A; Lichard, P; Luehring, F C; Lundberg, B; Maleev, V; Markina, I; McFarlane, K W; Mialkovski, V; Mitsou, V A; Mindur, B; Morozov, S; Munar, A; Muraviev, S; Nadtochy, A; Newcomer, F M; Ögren, H O; Oh, S H; Oleshko, S; Olszowska, J; Passmore, S; Patritchev, S; Peshekhonov, V D; Petti, R; Price, M; Rembser, C; Rohne, O; Romaniouk, A; Rust, D R; Ryabov, Yu; Shchegelskii, V; Seliverstov, D M; Shin, T; Shmeleva, A; Smirnov, S; Sosnovtsev, V V; Soutchkov, V; Spiridenkov, E; Tikhomirov, V; Van Berg, R; Vassilakopoulos, V I; Vassilieva, L; Wang, C; Williams, H H; Zalite, A

    2004-01-01

    Several prototypes of the Transition Radiation Tracker for the ATLAS experiment at the LHC have been built and tested at the CERN SPS accelerator. Results from detailed studies of the straw-tube hit registration efficiency and drift-time measurements and of the pion and electron spectra without and with radiators are presented. (10 refs).

  9. CMS tracker performance and readiness for LHC Run II

    Science.gov (United States)

    Viliani, L.

    2016-07-01

    The CMS tracker performance during LHC Run I is reviewed. The latest results of both pixel and strip detectors following the first LHC Long Shutdown (LS1) are then presented. Results from detector calibration and commissioning, together with a description of operations and repairs done during LS1, will be shown.

  10. Performance of the all-silicon CMS tracker

    Energy Technology Data Exchange (ETDEWEB)

    Caner, Alessandra E-mail: alessandra.caner@cern.ch

    2001-04-11

    The Compact Muon Solenoid (CMS) Tracker Collaboration has recently revised the tracking-detector layout. While the previous design relied on Micro Strip Gas Chamber (MSGC) and silicon detectors, the new layout implements solid state sensors as the sole technological choice. The new all-silicon layout is presented and the projected performance is discussed in terms of several benchmark topologies.

  11. Using "Tracker" to Prove the Simple Harmonic Motion Equation

    Science.gov (United States)

    Kinchin, John

    2016-01-01

    Simple harmonic motion (SHM) is a common topic for many students to study. Using the free, though versatile, motion tracking software; "Tracker", we can extend the students experience and show that the general equation for SHM does lead to the correct period of a simple pendulum.

  12. Using Tracker to prove the simple harmonic motion equation

    Science.gov (United States)

    Kinchin, John

    2016-09-01

    Simple harmonic motion (SHM) is a common topic for many students to study. Using the free, though versatile, motion tracking software; Tracker, we can extend the students experience and show that the general equation for SHM does lead to the correct period of a simple pendulum.

  13. Using Tracker as a Pedagogical Tool for Understanding Projectile Motion

    Science.gov (United States)

    Wee, Loo Kang; Chew, Charles; Goh, Giam Hwee; Tan, Samuel; Lee, Tat Leong

    2012-01-01

    This article reports on the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When a computer model building learning process is supported and driven by video analysis data, this free Open Source Physics tool can provide opportunities for students to engage in active enquiry-based…

  14. Neutrino Induced Coherent ρ Production in a Fine Grained Tracker

    Science.gov (United States)

    Jiang, Libo; Kullenberg, Christpher; Tian, Xinchun; Mishra, Sanjib; LBNE Collaboration

    2015-04-01

    We present simulation of neutrino induced coherent ρ-meson production in charged and neutral current interactions. Sensitivity studies of this process is presented in a fine grain tracker, a near detector option for LBNE. Measurements of coherent ρ0 and ρ+ production in NOMAD are reported.

  15. Mobile Autonomous Humanoid Assistant

    Science.gov (United States)

    Diftler, M. A.; Ambrose, R. O.; Tyree, K. S.; Goza, S. M.; Huber, E. L.

    2004-01-01

    A mobile autonomous humanoid robot is assisting human co-workers at the Johnson Space Center with tool handling tasks. This robot combines the upper body of the National Aeronautics and Space Administration (NASA)/Defense Advanced Research Projects Agency (DARPA) Robonaut system with a Segway(TradeMark) Robotic Mobility Platform yielding a dexterous, maneuverable humanoid perfect for aiding human co-workers in a range of environments. This system uses stereo vision to locate human team mates and tools and a navigation system that uses laser range and vision data to follow humans while avoiding obstacles. Tactile sensors provide information to grasping algorithms for efficient tool exchanges. The autonomous architecture utilizes these pre-programmed skills to form human assistant behaviors. The initial behavior demonstrates a robust capability to assist a human by acquiring a tool from a remotely located individual and then following the human in a cluttered environment with the tool for future use.

  16. Mobile Intelligent Autonomous Systems

    OpenAIRE

    Jitendra R. Raol; Ajith Gopal

    2010-01-01

    Mobile intelligent autonomous systems (MIAS) is a fast emerging research area. Although it can be regarded as a general R&D area, it is mainly directed towards robotics. Several important subtopics within MIAS research are:(i) perception and reasoning, (ii) mobility and navigation,(iii) haptics and teleoperation, (iv) image fusion/computervision, (v) modelling of manipulators, (vi) hardware/software architectures for planning and behaviour learning leadingto robotic architecture, (vii) ve...

  17. Nature's Autonomous Oscillators

    Science.gov (United States)

    Mayr, H. G.; Yee, J.-H.; Mayr, M.; Schnetzler, R.

    2012-01-01

    Nonlinearity is required to produce autonomous oscillations without external time dependent source, and an example is the pendulum clock. The escapement mechanism of the clock imparts an impulse for each swing direction, which keeps the pendulum oscillating at the resonance frequency. Among nature's observed autonomous oscillators, examples are the quasi-biennial oscillation and bimonthly oscillation of the Earth atmosphere, and the 22-year solar oscillation. The oscillations have been simulated in numerical models without external time dependent source, and in Section 2 we summarize the results. Specifically, we shall discuss the nonlinearities that are involved in generating the oscillations, and the processes that produce the periodicities. In biology, insects have flight muscles, which function autonomously with wing frequencies that far exceed the animals' neural capacity; Stretch-activation of muscle contraction is the mechanism that produces the high frequency oscillation of insect flight, discussed in Section 3. The same mechanism is also invoked to explain the functioning of the cardiac muscle. In Section 4, we present a tutorial review of the cardio-vascular system, heart anatomy, and muscle cell physiology, leading up to Starling's Law of the Heart, which supports our notion that the human heart is also a nonlinear oscillator. In Section 5, we offer a broad perspective of the tenuous links between the fluid dynamical oscillators and the human heart physiology.

  18. Trigeminal autonomic cephalalgias.

    Science.gov (United States)

    Eller, M; Goadsby, P J

    2016-01-01

    The trigeminal autonomic cephalalgias (TACs) are a group of primary headache disorders characterised by lateralized symptoms: prominent headache and ipsilateral cranial autonomic features, such as conjunctival injection, lacrimation and rhinorrhea. The TACs are: cluster headache (CH), paroxysmal hemicrania (PH), short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)/short-lasting neuralgiform headache attacks with cranial autonomic features (SUNA) and hemicrania continua (HC). Their diagnostic criteria are outlined in the International Classification of Headache Disorders, third edition-beta (ICHD-IIIb). These conditions are distinguished by their attack duration and frequency, as well as response to treatment. HC is continuous and by definition responsive to indomethacin. The main differential when considering this headache is chronic migraine. Other TACs are remarkable for their short duration and must be distinguished from other short-lasting painful conditions, such as trigeminal neuralgia and primary stabbing headache. Cluster headache is characterised by exquisitely painful attacks that occur in discrete episodes lasting 15-180 min a few times a day. In comparison, PH occurs more frequently and is of shorter duration, and like HC is responsive to indomethacin. SUNCT/SUNA is the shortest duration and highest frequency TAC; attacks can occur over a hundred times every day. PMID:24888770

  19. Trigeminal autonomic cephalalgias.

    Science.gov (United States)

    Eller, M; Goadsby, P J

    2016-01-01

    The trigeminal autonomic cephalalgias (TACs) are a group of primary headache disorders characterised by lateralized symptoms: prominent headache and ipsilateral cranial autonomic features, such as conjunctival injection, lacrimation and rhinorrhea. The TACs are: cluster headache (CH), paroxysmal hemicrania (PH), short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)/short-lasting neuralgiform headache attacks with cranial autonomic features (SUNA) and hemicrania continua (HC). Their diagnostic criteria are outlined in the International Classification of Headache Disorders, third edition-beta (ICHD-IIIb). These conditions are distinguished by their attack duration and frequency, as well as response to treatment. HC is continuous and by definition responsive to indomethacin. The main differential when considering this headache is chronic migraine. Other TACs are remarkable for their short duration and must be distinguished from other short-lasting painful conditions, such as trigeminal neuralgia and primary stabbing headache. Cluster headache is characterised by exquisitely painful attacks that occur in discrete episodes lasting 15-180 min a few times a day. In comparison, PH occurs more frequently and is of shorter duration, and like HC is responsive to indomethacin. SUNCT/SUNA is the shortest duration and highest frequency TAC; attacks can occur over a hundred times every day.

  20. Wave Star

    DEFF Research Database (Denmark)

    Kramer, Morten; Brorsen, Michael; Frigaard, Peter

    Denne rapport beskriver numeriske beregninger af forskellige flydergeometrier for bølgeenergianlæget Wave Star.......Denne rapport beskriver numeriske beregninger af forskellige flydergeometrier for bølgeenergianlæget Wave Star....

  1. A Novel Approach Based on MEMS-Gyro's Data Deep Coupling for Determining the Centroid of Star Spot

    OpenAIRE

    Xing Fei; Chen Nan; You Zheng; Sun Ting

    2012-01-01

    The traditional approach of star tracker for determining the centroid of spot requires enough energy and good shape, so a relatively long exposure time and stable three-axis state become necessary conditions to maintain high accuracy, these limit its update rate and dynamic performance. In view of these issues, this paper presents an approach for determining the centroid of star spot which based on MEMS-Gyro's data deep coupling, it achieves the deep fusion of the data of star tracker and MEM...

  2. Massive Stars

    Science.gov (United States)

    Livio, Mario; Villaver, Eva

    2009-11-01

    Participants; Preface Mario Livio and Eva Villaver; 1. High-mass star formation by gravitational collapse of massive cores M. R. Krumholz; 2. Observations of massive star formation N. A. Patel; 3. Massive star formation in the Galactic center D. F. Figer; 4. An X-ray tour of massive star-forming regions with Chandra L. K. Townsley; 5. Massive stars: feedback effects in the local universe M. S. Oey and C. J. Clarke; 6. The initial mass function in clusters B. G. Elmegreen; 7. Massive stars and star clusters in the Antennae galaxies B. C. Whitmore; 8. On the binarity of Eta Carinae T. R. Gull; 9. Parameters and winds of hot massive stars R. P. Kudritzki and M. A. Urbaneja; 10. Unraveling the Galaxy to find the first stars J. Tumlinson; 11. Optically observable zero-age main-sequence O stars N. R. Walborn; 12. Metallicity-dependent Wolf-Raynet winds P. A. Crowther; 13. Eruptive mass loss in very massive stars and Population III stars N. Smith; 14. From progenitor to afterlife R. A. Chevalier; 15. Pair-production supernovae: theory and observation E. Scannapieco; 16. Cosmic infrared background and Population III: an overview A. Kashlinsky.

  3. Hadron star models. [neutron stars

    Science.gov (United States)

    Cohen, J. M.; Boerner, G.

    1974-01-01

    The properties of fully relativistic rotating hadron star models are discussed using models based on recently developed equations of state. All of these stable neutron star models are bound with binding energies as high as about 25%. During hadron star formation, much of this energy will be released. The consequences, resulting from the release of this energy, are examined.

  4. Jam avoidance with autonomous systems

    OpenAIRE

    Tordeux, Antoine; Lassarre, Sylvain

    2015-01-01

    Many car-following models are developed for jam avoidance in highways. Two mechanisms are used to improve the stability: feedback control with autonomous models and increasing of the interaction within cooperative ones. In this paper, we compare the linear autonomous and collective optimal velocity (OV) models. We observe that the stability is significantly increased by adding predecessors in interaction with collective models. Yet autonomous and collective approaches are close when the speed...

  5. Chemical Specification of Autonomic Systems

    OpenAIRE

    Banâtre, Jean-Pierre; Fradet, Pascal; Radenac, Yann

    2004-01-01

    Autonomic computing provides a vision of information systems allowing self-management of many predefined properties. Such systems take care of their own behavior and of their interactions with other components without any external intervention. One of the major challenges concerns the expression of properties and constraints of autonomic systems. We believe that the {\\em chemical programming paradigm} (represented here by the Gamma formalism) is well-suited to the specification of autonomic s...

  6. Jam avoidance with autonomous systems

    CERN Document Server

    Tordeux, Antoine

    2016-01-01

    Many car-following models are developed for jam avoidance in highways. Two mechanisms are used to improve the stability: feedback control with autonomous models and increasing of the interaction within cooperative ones. In this paper, we compare the linear autonomous and collective optimal velocity (OV) models. We observe that the stability is significantly increased by adding predecessors in interaction with collective models. Yet autonomous and collective approaches are close when the speed difference term is taking into account. Within the linear OV models tested, the autonomous models including speed difference are sufficient to maximise the stability.

  7. Robotics and Autonomous Systems Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Provides an environment for developing and evaluating intelligent software for both actual and simulated autonomous vehicles. Laboratory computers provide...

  8. Autonomous packaging robot

    OpenAIRE

    Vo, Van Thanh

    2010-01-01

    The objective of the autonomous packaging robot application is to replace manual product packaging in food industry with a fully automatic robot. The objective is achieved by using the combination of machine vision, central computer, sensors, microcontroller and a typical ABB robot. The method is to equip the robot with different sensors: camera as “eyes” of robot, distance sensor and microcontroller as “sense of touch” of the robot, central computer as “brain” of the robot. Because the ro...

  9. Experimental Autonomous Vehicle Systems

    DEFF Research Database (Denmark)

    Ravn, Ole; Andersen, Nils Axel

    1998-01-01

    The paper describes the requirements for and a prototype configuration of a software architecture for control of an experimental autonomous vehicle. The test bed nature of the system is emphasised in the choice of architecture making re-configurability, data logging and extendability simple....... The central element of the architecture is the ‘global database’ that serves several purposes, such as storing system parameters, making signals available for data logging and inter-process communication. Standard software components are used to a large extent, OS-9 as real-time operating system, a custom...

  10. Using Tracker as a Pedagogical Tool for Understanding Projectile Motion

    CERN Document Server

    Wee, Loo Kang; Goh, Giam Hwee; Tan, Samuel; Lee, Tat Leong

    2012-01-01

    This paper reports the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When computer model building learning processes is supported and driven by video analysis data, this free Open Source Physics (OSP) tool can provide opportunities for students to engage in active inquiry-based learning. We discuss the pedagogical use of Tracker to address some common misconceptions of projectile motion by allowing students to test their hypothesis by juxtaposing their mental models against the analysis of real life videos. Initial research findings suggest that allowing learners to relate abstract physics concepts to real life through coupling computer modeling with traditional video analysis could be an innovative and effective way to learn projectile motion.

  11. Commissioning of the ATLAS Semiconductor Tracker with cosmic rays

    Science.gov (United States)

    Stanecka, E.; Atlas Sct Collaboration

    2007-10-01

    This paper presents the results of the tests with cosmic rays of the ATLAS Semiconductor Tracker (SCT) as well as operational experience of running the fully integrated silicon detector during the commissioning of the completed SCT. Prior to inserting into ATLAS, the barrel part of the SCT has been integrated with the Transition Radiation Tracker (TRT) barrel and tested with cosmic rays. A sector of 468 SCT modules has been powered and read simultaneously with TRT modules in physics mode. In total 500 thousand events were recorded during cosmic runs and processed with the ATLAS off-line reconstruction software. The SCT performance was measured in terms of the average noise occupancy per channel (4.5×10-5) and the overall efficiency (>99%). The tests with cosmic rays proved full functionality of the complex Detector Control System (DCS) which provides control, monitoring and safety functions for the detector electronics.

  12. Technical Feasibility Studies for the CMS Tracker Position Monitoring System

    CERN Document Server

    Alemany, R; Ahmad, F; Akhtar, Shabbir; Ali, Arshad; Ali, Liaqat; Ashraf, M; Da Mota Silva, Suzana; Hameed-Khan, S; Höpfner, K; Parvez, Ansar; Ribeiro, Rui; Suleman, Badar; Voss, Helge

    2001-01-01

    CMS will use a tracker comprised of about 2~times10^4 silicon sensors operating inside the 4T magnetic field at about-20~^oC for the entire lifetime of the experiment. The tracker is composed of four mechanically independent structures. To monitor the stability of this system under running conditions a position monitoring system is necessary. It has to guarantee position tolerances at the level of 0.1~mm as a starting point for the alignment with track procedures. In view of the design of a positon monitoring system various components of potential interest have been studied and tested under laboratory conditions to guarantee a reliable and cost-effective design. This document compiles the related R&D of general interest: detailed studies of carbon fibre structures, the optical transmission of silicon, radiation hardness of optical components and the stability of a distributed laser light system.

  13. Operation and performance of the ATLAS semiconductor tracker

    CERN Document Server

    Aad, Georges; Abdallah, Jalal; Abdel Khalek, Samah; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Agatonovic-Jovin, Tatjana; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Ahlen, Steven; Ahmad, Ashfaq; Ahmadov, Faig; Aielli, Giulio; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Alimonti, Gianluca; Alio, Lion; Alison, John; Allbrooke, Benedict; Allison, Lee John; Allport, Phillip; Allwood-Spiers, Sarah; Almond, John; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; Alviggi, Mariagrazia; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Anduaga, Xabier; Angelidakis, Stylianos; Angelozzi, Ivan; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Apolle, Rudi; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Arnold, Hannah; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Ask, Stefan; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Auerbach, Benjamin; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Azuelos, Georges; Azuma, Yuya; Baak, Max; Bacci, Cesare; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Backus Mayes, John; Badescu, Elisabeta; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Bain, Travis; Baines, John; Baker, Oliver Keith; Baker, Sarah; Balek, Petr; Balli, Fabrice; Banas, Elzbieta; Banerjee, Swagato; Banfi, Danilo; Bangert, Andrea Michelle; Bannoura, Arwa A E; Bansal, Vikas; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnett, Bruce; Barnett, Michael; Barnovska, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Bartsch, Valeria; Bassalat, Ahmed; Basye, Austin; Bates, Richard; Batkova, Lucia; Batley, Richard; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Anne Kathrin; Becker, Sebastian; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bedikian, Sourpouhi; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Katharina; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belloni, Alberto; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Bensinger, James; Benslama, Kamal; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Berglund, Elina; Beringer, Jürg; Bernabéu, José; Bernard, Clare; Bernat, Pauline; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertolucci, Federico; Besana, Maria Ilaria; Besjes, Geert-Jan; Bessidskaia, Olga; Besson, Nathalie; Betancourt, Christopher; Bethke, Siegfried; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Bierwagen, Katharina; Biesiada, Jed; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien; Bingul, Ahmet; Bini, Cesare; Black, Curtis; Black, James; Black, Kevin; Blackburn, Daniel; Blair, Robert; Blanchard, Jean-Baptiste; Blazek, Tomas; Bloch, Ingo; Blocker, Craig; Blum, Walter; Blumenschein, Ulrike; Bobbink, Gerjan; Bobrovnikov, Victor; Bocchetta, Simona Serena; Bocci, Andrea; Boddy, Christopher Richard; Boehler, Michael; Boek, Jennifer; Boek, Thorsten Tobias; Bogaerts, Joannes Andreas; Bogdanchikov, Alexander; Bogouch, Andrei; Bohm, Christian; Bohm, Jan; Boisvert, Veronique; Bold, Tomasz; Boldea, Venera; Boldyrev, Alexey; Bomben, Marco; Bona, Marcella; Boonekamp, Maarten; Borisov, Anatoly; Borissov, Guennadi; Borri, Marcello; Borroni, Sara; Bortfeldt, Jonathan; Bortolotto, Valerio; Bos, Kors; Boscherini, Davide; Bosman, Martine; Boterenbrood, Hendrik; Boudreau, Joseph; Bouffard, Julian; Bouhova-Thacker, Evelina Vassileva; Boumediene, Djamel Eddine; Bourdarios, Claire; Bousson, Nicolas; Boutouil, Sara; Boveia, Antonio; Boyd, James; Boyko, Igor; Bozovic-Jelisavcic, Ivanka; Bracinik, Juraj; Branchini, Paolo; Brandt, Andrew; Brandt, Gerhard; Brandt, Oleg; Bratzler, Uwe; Brau, Benjamin; Brau, James; Braun, Helmut; Brazzale, Simone Federico; Brelier, Bertrand; Brendlinger, Kurt; Brennan, Amelia Jean; Brenner, Richard; Bressler, Shikma; Bristow, Kieran; Bristow, Timothy Michael; Britton, Dave; Brochu, Frederic; Brock, Ian; Brock, Raymond; Bromberg, Carl; Bronner, Johanna; Brooijmans, Gustaaf; Brooks, Timothy; Brooks, William; Brosamer, Jacquelyn; Brost, Elizabeth; Brown, Gareth; Brown, Jonathan; Bruckman de Renstrom, Pawel; Bruncko, Dusan; Bruneliere, Renaud; Brunet, Sylvie; Bruni, Alessia; Bruni, Graziano; Bruschi, Marco; Bryngemark, Lene; Buanes, Trygve; Buat, Quentin; Bucci, Francesca; Buchholz, Peter; Buckingham, Ryan; Buckley, Andrew; Buda, Stelian Ioan; Budagov, Ioulian; Buehrer, Felix; Bugge, Lars; Bugge, Magnar Kopangen; Bulekov, Oleg; Bundock, Aaron Colin; Burckhart, Helfried; Burdin, Sergey; Burghgrave, Blake; Burke, Stephen; Burmeister, Ingo; Busato, Emmanuel; Büscher, Daniel; Büscher, Volker; Bussey, Peter; Buszello, Claus-Peter; Butler, Bart; Butler, John; Butt, Aatif Imtiaz; Buttar, Craig; Butterworth, Jonathan; Butti, Pierfrancesco; Buttinger, William; Buzatu, Adrian; Byszewski, Marcin; Cabrera Urbán, Susana; Caforio, Davide; Cakir, Orhan; Calafiura, Paolo; Calandri, Alessandro; Calderini, Giovanni; Calfayan, Philippe; Calkins, Robert; Caloba, Luiz; Calvet, David; Calvet, Samuel; Camacho Toro, Reina; Camarda, Stefano; Cameron, David; Caminada, Lea Michaela; Caminal Armadans, Roger; Campana, Simone; Campanelli, Mario; Campoverde, Angel; Canale, Vincenzo; Canepa, Anadi; Cantero, Josu; Cantrill, Robert; Cao, Tingting; Capeans Garrido, Maria Del Mar; Caprini, Irinel; Caprini, Mihai; Capua, Marcella; Caputo, Regina; Cardarelli, Roberto; Carli, Tancredi; Carlino, Gianpaolo; Carminati, Leonardo; Caron, Sascha; Carquin, Edson; Carrillo-Montoya, German D; Carter, Antony; Carter, Janet; Carvalho, João; Casadei, Diego; Casado, Maria Pilar; Castaneda-Miranda, Elizabeth; Castelli, Angelantonio; Castillo Gimenez, Victoria; Castro, Nuno Filipe; Catastini, Pierluigi; Catinaccio, Andrea; Catmore, James; Cattai, Ariella; Cattani, Giordano; Caughron, Seth; Cavaliere, Viviana; Cavalli, Donatella; Cavalli-Sforza, Matteo; Cavasinni, Vincenzo; Ceradini, Filippo; Cerio, Benjamin; Cerny, Karel; Cerqueira, Augusto Santiago; Cerri, Alessandro; Cerrito, Lucio; Cerutti, Fabio; Cerv, Matevz; Cervelli, Alberto; Cetin, Serkant Ali; Chafaq, Aziz; Chakraborty, Dhiman; Chalupkova, Ina; Chan, Kevin; Chang, Philip; Chapleau, Bertrand; Chapman, John Derek; Charfeddine, Driss; Charlton, Dave; Chau, Chav Chhiv; Chavez Barajas, Carlos Alberto; Cheatham, Susan; Chegwidden, Andrew; Chekanov, Sergei; Chekulaev, Sergey; Chelkov, Gueorgui; Chelstowska, Magda Anna; Chen, Chunhui; Chen, Hucheng; Chen, Karen; Chen, Liming; Chen, Shenjian; Chen, Xin; Chen, Yujiao; Cheng, Hok Chuen; Cheng, Yangyang; Cheplakov, Alexander; Cherkaoui El Moursli, Rajaa; Chernyatin, Valeriy; Cheu, Elliott; Chevalier, Laurent; Chiarella, Vitaliano; Chiefari, Giovanni; Childers, John Taylor; Chilingarov, Alexandre; Chiodini, Gabriele; Chisholm, Andrew; Chislett, Rebecca Thalatta; Chitan, Adrian; Chizhov, Mihail; Chouridou, Sofia; Chow, Bonnie Kar Bo; Christidi, Ilektra-Athanasia; Chromek-Burckhart, Doris; Chu, Ming-Lee; Chudoba, Jiri; Chwastowski, Janusz; Chytka, Ladislav; Ciapetti, Guido; Ciftci, Abbas Kenan; Ciftci, Rena; Cinca, Diane; Cindro, Vladimir; Ciocio, Alessandra; Cirkovic, Predrag; Citron, Zvi Hirsh; Citterio, Mauro; Ciubancan, Mihai; Clark, Allan G; Clark, Philip James; Clarke, Robert; Cleland, Bill; Clemens, Jean-Claude; Clement, Christophe; Coadou, Yann; Cobal, Marina; Coccaro, Andrea; Cochran, James H; Coffey, Laurel; Cogan, Joshua Godfrey; Coggeshall, James; Cole, Brian; Cole, Stephen; Colijn, Auke-Pieter; Collins-Tooth, Christopher; Collot, Johann; Colombo, Tommaso; Colon, German; Compostella, Gabriele; Conde Muiño, Patricia; Coniavitis, Elias; Conidi, Maria Chiara; Connell, Simon Henry; Connelly, Ian; Consonni, Sofia Maria; Consorti, Valerio; Constantinescu, Serban; Conta, Claudio; Conti, Geraldine; Conventi, Francesco; Cooke, Mark; Cooper, Ben; Cooper-Sarkar, Amanda; Cooper-Smith, Neil; Copic, Katherine; Cornelissen, Thijs; Corradi, Massimo; Corriveau, Francois; Corso-Radu, Alina; Cortes-Gonzalez, Arely; Cortiana, Giorgio; Costa, Giuseppe; Costa, María José; Costanzo, Davide; Côté, David; Cottin, Giovanna; Cowan, Glen; Cox, Brian; Cranmer, Kyle; Cree, Graham; Crépé-Renaudin, Sabine; Crescioli, Francesco; Crispin Ortuzar, Mireia; Cristinziani, Markus; Croft, Vince; Crosetti, Giovanni; Cuciuc, Constantin-Mihai; Cuenca Almenar, Cristóbal; Cuhadar Donszelmann, Tulay; Cummings, Jane; Curatolo, Maria; Cuthbert, Cameron; Czirr, Hendrik; Czodrowski, Patrick; Czyczula, Zofia; D'Auria, Saverio; D'Onofrio, Monica; Da Cunha Sargedas De Sousa, Mario Jose; Da Via, Cinzia; Dabrowski, Wladyslaw; Dafinca, Alexandru; Dai, Tiesheng; Dale, Orjan; Dallaire, Frederick; Dallapiccola, Carlo; Dam, Mogens; Daniells, Andrew Christopher; Dano Hoffmann, Maria; Dao, Valerio; Darbo, Giovanni; Darlea, Georgiana Lavinia; Darmora, Smita; Dassoulas, James; Dattagupta, Aparajita; Davey, Will; David, Claire; Davidek, Tomas; Davies, Eleanor; Davies, Merlin; Davignon, Olivier; Davison, Adam; Davison, Peter; Davygora, Yuriy; Dawe, Edmund; Dawson, Ian; Daya-Ishmukhametova, Rozmin; De, Kaushik; de Asmundis, Riccardo; De Castro, Stefano; De Cecco, Sandro; de Graat, Julien; De Groot, Nicolo; de Jong, Paul; De la Torre, Hector; De Lorenzi, Francesco; De Nooij, Lucie; De Pedis, Daniele; De Salvo, Alessandro; De Sanctis, Umberto; De Santo, Antonella; De Vivie De Regie, Jean-Baptiste; De Zorzi, Guido; Dearnaley, William James; Debbe, Ramiro; Debenedetti, Chiara; Dechenaux, Benjamin; Dedovich, Dmitri; Degenhardt, James; Deigaard, Ingrid; Del Peso, Jose; Del Prete, Tarcisio; Deliot, Frederic; Delitzsch, Chris Malena; Deliyergiyev, Maksym; Dell'Acqua, Andrea; Dell'Asta, Lidia; Dell'Orso, Mauro; Della Pietra, Massimo; della Volpe, Domenico; Delmastro, Marco; Delsart, Pierre-Antoine; Deluca, Carolina; Demers, Sarah; Demichev, Mikhail; Demilly, Aurelien; Denisov, Sergey; Derendarz, Dominik; Derkaoui, Jamal Eddine; Derue, Frederic; Dervan, Paul; Desch, Klaus Kurt; Deterre, Cecile; Deviveiros, Pier-Olivier; Dewhurst, Alastair; Dhaliwal, Saminder; Di Ciaccio, Anna; Di Ciaccio, Lucia; Di Domenico, Antonio; Di Donato, Camilla; Di Girolamo, Alessandro; Di Girolamo, Beniamino; Di Mattia, Alessandro; Di Micco, Biagio; Di Nardo, Roberto; Di Simone, Andrea; Di Sipio, Riccardo; Di Valentino, David; Diaz, Marco Aurelio; Diehl, Edward; Dietrich, Janet; Dietzsch, Thorsten; Diglio, Sara; Dimitrievska, Aleksandra; Dingfelder, Jochen; Dionisi, Carlo; Dita, Petre; Dita, Sanda; Dittus, Fridolin; Djama, Fares; Djobava, Tamar; do Vale, Maria Aline Barros; Do Valle Wemans, André; Doan, Thi Kieu Oanh; Dobos, Daniel; Dobson, Ellie; Doglioni, Caterina; Doherty, Tom; Dohmae, Takeshi; Dolejsi, Jiri; Dolezal, Zdenek; Dolgoshein, Boris; Donadelli, Marisilvia; Donati, Simone; Dondero, Paolo; Donini, Julien; Dopke, Jens; Doria, Alessandra; Dos Anjos, Andre; Dova, Maria-Teresa; Doyle, Tony; Dris, Manolis; Dubbert, Jörg; Dube, Sourabh; Dubreuil, Emmanuelle; Duchovni, Ehud; Duckeck, Guenter; Ducu, Otilia Anamaria; Duda, Dominik; Dudarev, Alexey; Dudziak, Fanny; Duflot, Laurent; Duguid, Liam; Dührssen, Michael; Dunford, Monica; Duran Yildiz, Hatice; Düren, Michael; Durglishvili, Archil; Dwuznik, Michal; Dyndal, Mateusz; Ebke, Johannes; Edson, William; Edwards, Nicholas Charles; Ehrenfeld, Wolfgang; Eifert, Till; Eigen, Gerald; Einsweiler, Kevin; Ekelof, Tord; El Kacimi, Mohamed; Ellert, Mattias; Elles, Sabine; Ellinghaus, Frank; Ellis, Nicolas; Elmsheuser, Johannes; Elsing, Markus; Emeliyanov, Dmitry; Enari, Yuji; Endner, Oliver Chris; Endo, Masaki; Engelmann, Roderich; Erdmann, Johannes; Ereditato, Antonio; Eriksson, Daniel; Ernis, Gunar; Ernst, Jesse; Ernst, Michael; Ernwein, Jean; Errede, Deborah; Errede, Steven; Ertel, Eugen; Escalier, Marc; Esch, Hendrik; Escobar, Carlos; Esposito, Bellisario; Etienvre, Anne-Isabelle; Etzion, Erez; Evans, Hal; Fabbri, Laura; Facini, Gabriel; Fakhrutdinov, Rinat; Falciano, Speranza; Faltova, Jana; Fang, Yaquan; Fanti, Marcello; Farbin, Amir; Farilla, Addolorata; Farooque, Trisha; Farrell, Steven; Farrington, Sinead; Farthouat, Philippe; Fassi, Farida; Fassnacht, Patrick; Fassouliotis, Dimitrios; Favareto, Andrea; Fayard, Louis; Federic, Pavol; Fedin, Oleg; Fedorko, Wojciech; Fehling-Kaschek, Mirjam; Feigl, Simon; Feligioni, Lorenzo; Feng, Cunfeng; Feng, Eric; Feng, Haolu; Fenyuk, Alexander; Fernandez Perez, Sonia; Ferrag, Samir; Ferrando, James; Ferrari, Arnaud; Ferrari, Pamela; Ferrari, Roberto; Ferreira de Lima, Danilo Enoque; Ferrer, Antonio; Ferrere, Didier; Ferretti, Claudio; Ferretto Parodi, Andrea; Fiascaris, Maria; Fiedler, Frank; Filipčič, Andrej; Filipuzzi, Marco; Filthaut, Frank; Fincke-Keeler, Margret; Finelli, Kevin Daniel; Fiolhais, Miguel; Fiorini, Luca; Firan, Ana; Fischer, Julia; Fisher, Wade Cameron; Fitzgerald, Eric Andrew; Flechl, Martin; Fleck, Ivor; Fleischmann, Philipp; Fleischmann, Sebastian; Fletcher, Gareth Thomas; Fletcher, Gregory; Flick, Tobias; Floderus, Anders; Flores Castillo, Luis; Florez Bustos, Andres Carlos; Flowerdew, Michael; Formica, Andrea; Forti, Alessandra; Fortin, Dominique; Fournier, Daniel; Fox, Harald; Fracchia, Silvia; Francavilla, Paolo; Franchini, Matteo; Franchino, Silvia; Francis, David; Franklin, Melissa; Franz, Sebastien; Fraternali, Marco; French, Sky; Friedrich, Conrad; Friedrich, Felix; Froidevaux, Daniel; Frost, James; Fukunaga, Chikara; Fullana Torregrosa, Esteban; Fulsom, Bryan Gregory; Fuster, Juan; Gabaldon, Carolina; Gabizon, Ofir; Gabrielli, Alessandro; Gabrielli, Andrea; Gadatsch, Stefan; Gadomski, Szymon; Gagliardi, Guido; Gagnon, Pauline; Galea, Cristina; Galhardo, Bruno; Gallas, Elizabeth; Gallo, Valentina Santina; Gallop, Bruce; Gallus, Petr; Galster, Gorm Aske Gram Krohn; Gan, KK; Gandrajula, Reddy Pratap; Gao, Jun; Gao, Yongsheng; Garay Walls, Francisca; Garberson, Ford; García, Carmen; Garcia Argos, Carlos; García Navarro, José Enrique; Garcia-Sciveres, Maurice; Gardner, Robert; Garelli, Nicoletta; Garonne, Vincent; Gatti, Claudio; Gaudio, Gabriella; Gaur, Bakul; Gauthier, Lea; Gauzzi, Paolo; Gavrilenko, Igor; Gay, Colin; Gaycken, Goetz; Gazis, Evangelos; Ge, Peng; Gecse, Zoltan; Gee, Norman; Geerts, Daniël Alphonsus Adrianus; Geich-Gimbel, Christoph; Gellerstedt, Karl; Gemme, Claudia; Gemmell, Alistair; Genest, Marie-Hélène; Gentile, Simonetta; George, Matthias; George, Simon; Gerbaudo, Davide; Gershon, Avi; Ghazlane, Hamid; Ghodbane, Nabil; Giacobbe, Benedetto; Giagu, Stefano; Giangiobbe, Vincent; Giannetti, Paola; Gianotti, Fabiola; Gibbard, Bruce; Gibson, Stephen; Gilchriese, Murdock; Gillam, Thomas; Gillberg, Dag; Gilles, Geoffrey; Gingrich, Douglas; Giokaris, Nikos; Giordani, MarioPaolo; Giordano, Raffaele; Giorgi, Francesco Michelangelo; Giraud, Pierre-Francois; Giugni, Danilo; Giuliani, Claudia; Giulini, Maddalena; Gjelsten, Børge Kile; Gkialas, Ioannis; Gladilin, Leonid; Glasman, Claudia; Glatzer, Julian; Glaysher, Paul; Glazov, Alexandre; Glonti, George; Goblirsch-Kolb, Maximilian; Goddard, Jack Robert; Godfrey, Jennifer; Godlewski, Jan; Goeringer, Christian; Goldfarb, Steven; Golling, Tobias; Golubkov, Dmitry; Gomes, Agostinho; Gomez Fajardo, Luz Stella; Gonçalo, Ricardo; Goncalves Pinto Firmino Da Costa, Joao; Gonella, Laura; González de la Hoz, Santiago; Gonzalez Parra, Garoe; Gonzalez Silva, Laura; Gonzalez-Sevilla, Sergio; Goodrick, Maurice; Goossens, Luc; Gorbounov, Petr Andreevich; Gordon, Howard; Gorelov, Igor; Gorfine, Grant; Gorini, Benedetto; Gorini, Edoardo; Gorišek, Andrej; Gornicki, Edward; Goshaw, Alfred; Gössling, Claus; Gostkin, Mikhail Ivanovitch; Gouighri, Mohamed; Goujdami, Driss; Goulette, Marc Phillippe; Goussiou, Anna; Goy, Corinne; Gozpinar, Serdar; Grabas, Herve Marie Xavier; Graber, Lars; Grabowska-Bold, Iwona; Grafström, Per; Grahn, Karl-Johan; Gramling, Johanna; Gramstad, Eirik; Grancagnolo, Sergio; Grassi, Valerio; Gratchev, Vadim; Gray, Heather; Graziani, Enrico; Grebenyuk, Oleg; Greenwood, Zeno Dixon; Gregersen, Kristian; Gregor, Ingrid-Maria; Grenier, Philippe; Griffiths, Justin; Grigalashvili, Nugzar; Grillo, Alexander; Grimm, Kathryn; Grinstein, Sebastian; Gris, Philippe Luc Yves; Grishkevich, Yaroslav; Grivaz, Jean-Francois; Grohs, Johannes Philipp; Grohsjean, Alexander; Gross, Eilam; Grosse-Knetter, Joern; Grossi, Giulio Cornelio; Groth-Jensen, Jacob; Grout, Zara Jane; Grybel, Kai; Guan, Liang; Guescini, Francesco; Guest, Daniel; Gueta, Orel; Guicheney, Christophe; Guido, Elisa; Guillemin, Thibault; Guindon, Stefan; Gul, Umar; Gumpert, Christian; Gunther, Jaroslav; Guo, Jun; Gupta, Shaun; Gutierrez, Phillip; Gutierrez Ortiz, Nicolas Gilberto; Gutschow, Christian; Guttman, Nir; Guyot, Claude; Gwenlan, Claire; Gwilliam, Carl; Haas, Andy; Haber, Carl; Hadavand, Haleh Khani; Haddad, Nacim; Haefner, Petra; Hageboeck, Stephan; Hajduk, Zbigniew; Hakobyan, Hrachya; Haleem, Mahsana; Hall, David; Halladjian, Garabed; Hamacher, Klaus; Hamal, Petr; Hamano, Kenji; Hamer, Matthias; Hamilton, Andrew; Hamilton, Samuel; Hamnett, Phillip George; Han, Liang; Hanagaki, Kazunori; Hanawa, Keita; Hance, Michael; Hanke, Paul; Hansen, Jørgen Beck; Hansen, Jorn Dines; Hansen, Peter Henrik; Hara, Kazuhiko; Hard, Andrew; Harenberg, Torsten; Harkusha, Siarhei; Harper, Devin; Harrington, Robert; Harris, Orin; Harrison, Paul Fraser; Hartjes, Fred; Hasegawa, Satoshi; Hasegawa, Yoji; Hasib, A; Hassani, Samira; Haug, Sigve; Hauschild, Michael; Hauser, Reiner; Havranek, Miroslav; Hawkes, Christopher; Hawkings, Richard John; Hawkins, Anthony David; Hayashi, Takayasu; Hayden, Daniel; Hays, Chris; Hayward, Helen; Haywood, Stephen; Head, Simon; Heck, Tobias; Hedberg, Vincent; Heelan, Louise; Heim, Sarah; Heim, Timon; Heinemann, Beate; Heinrich, Lukas; Heisterkamp, Simon; Hejbal, Jiri; Helary, Louis; Heller, Claudio; Heller, Matthieu; Hellman, Sten; Hellmich, Dennis; Helsens, Clement; Henderson, James; Henderson, Robert; Hengler, Christopher; Henrichs, Anna; Henriques Correia, Ana Maria; Henrot-Versille, Sophie; Hensel, Carsten; Herbert, Geoffrey Henry; Hernández Jiménez, Yesenia; Herrberg-Schubert, Ruth; Herten, Gregor; Hertenberger, Ralf; Hervas, Luis; Hesketh, Gavin Grant; Hessey, Nigel; Hickling, Robert; Higón-Rodriguez, Emilio; Hill, Ewan; Hill, John; Hiller, Karl Heinz; Hillert, Sonja; Hillier, Stephen; Hinchliffe, Ian; Hines, Elizabeth; Hirose, Minoru; Hirschbuehl, Dominic; Hobbs, John; Hod, Noam; Hodgkinson, Mark; Hodgson, Paul; Hoecker, Andreas; Hoeferkamp, Martin; Hoffman, Julia; Hoffmann, Dirk; Hofmann, Julia Isabell; Hohlfeld, Marc; Holmes, Tova Ray; Hong, Tae Min; Hooft van Huysduynen, Loek; Hostachy, Jean-Yves; Hou, Suen; Hoummada, Abdeslam; Howard, Jacob; Howarth, James; Hrabovsky, Miroslav; Hristova, Ivana; Hrivnac, Julius; Hryn'ova, Tetiana; Hsu, Pai-hsien Jennifer; Hsu, Shih-Chieh; Hu, Diedi; Hu, Xueye; Huang, Yanping; Hubacek, Zdenek; Hubaut, Fabrice; Huegging, Fabian; Huffman, Todd Brian; Hughes, Emlyn; Hughes, Gareth; Huhtinen, Mika; Hülsing, Tobias Alexander; Hurwitz, Martina; Huseynov, Nazim; Huston, Joey; Huth, John; Iacobucci, Giuseppe; Iakovidis, Georgios; Ibragimov, Iskander; Iconomidou-Fayard, Lydia; Idarraga, John; Ideal, Emma; Iengo, Paolo; Igonkina, Olga; Iizawa, Tomoya; Ikegami, Yoichi; Ikematsu, Katsumasa; Ikeno, Masahiro; Iliadis, Dimitrios; Ilic, Nikolina; Inamaru, Yuki; Ince, Tayfun; Ioannou, Pavlos; Iodice, Mauro; Iordanidou, Kalliopi; Ippolito, Valerio; Irles Quiles, Adrian; Isaksson, Charlie; Ishino, Masaya; Ishitsuka, Masaki; Ishmukhametov, Renat; Issever, Cigdem; Istin, Serhat; Iturbe Ponce, Julia Mariana; Ivarsson, Jenny; Ivashin, Anton; Iwanski, Wieslaw; Iwasaki, Hiroyuki; Izen, Joseph; Izzo, Vincenzo; Jackson, Brett; Jackson, John; Jackson, Matthew; Jackson, Paul; Jaekel, Martin; Jain, Vivek; Jakobs, Karl; Jakobsen, Sune; Jakoubek, Tomas; Jakubek, Jan; Jamin, David Olivier; Jana, Dilip; Jansen, Eric; Jansen, Hendrik; Janssen, Jens; Janus, Michel; Jarlskog, Göran; Javadov, Namig; Javůrek, Tomáš; Jeanty, Laura; Jeng, Geng-yuan; Jennens, David; Jenni, Peter; Jentzsch, Jennifer; Jeske, Carl; Jézéquel, Stéphane; Ji, Haoshuang; Ji, Weina; Jia, Jiangyong; Jiang, Yi; Jimenez Belenguer, Marcos; Jin, Shan; Jinaru, Adam; Jinnouchi, Osamu; Joergensen, Morten Dam; Johansson, Erik; Johansson, Per; Johns, Kenneth; Jon-And, Kerstin; Jones, Graham; Jones, Roger; Jones, Tim; Jongmanns, Jan; Jorge, Pedro; Joseph, John; Joshi, Kiran Daniel; Jovicevic, Jelena; Ju, Xiangyang; Jung, Christian; Jungst, Ralph Markus; Jussel, Patrick; Juste Rozas, Aurelio; Kaci, Mohammed; Kaczmarska, Anna; Kado, Marumi; Kagan, Harris; Kagan, Michael; Kajomovitz, Enrique; Kama, Sami; Kanaya, Naoko; Kaneda, Michiru; Kaneti, Steven; Kanno, Takayuki; Kantserov, Vadim; Kanzaki, Junichi; Kaplan, Benjamin; Kapliy, Anton; Kar, Deepak; Karakostas, Konstantinos; Karastathis, Nikolaos; Karnevskiy, Mikhail; Karpov, Sergey; Karthik, Krishnaiyengar; Kartvelishvili, Vakhtang; Karyukhin, Andrey; Kashif, Lashkar; Kasieczka, Gregor; Kass, Richard; Kastanas, Alex; Kataoka, Yousuke; Katre, Akshay; Katzy, Judith; Kaushik, Venkatesh; Kawagoe, Kiyotomo; Kawamoto, Tatsuo; Kawamura, Gen; Kazama, Shingo; Kazanin, Vassili; Kazarinov, Makhail; Keeler, Richard; Keener, Paul; Kehoe, Robert; Keil, Markus; Keller, John; Keoshkerian, Houry; Kepka, Oldrich; Kerševan, Borut Paul; Kersten, Susanne; Kessoku, Kohei; Keung, Justin; Khalil-zada, Farkhad; Khandanyan, Hovhannes; Khanov, Alexander; Khodinov, Alexander; Khomich, Andrei; Khoo, Teng Jian; Khoriauli, Gia; Khoroshilov, Andrey; Khovanskiy, Valery; Khramov, Evgeniy; Khubua, Jemal; Kim, Hee Yeun; Kim, Hyeon Jin; Kim, Shinhong; Kimura, Naoki; Kind, Oliver; King, Barry; King, Matthew; King, Robert Steven Beaufoy; King, Samuel Burton; Kirk, Julie; Kiryunin, Andrey; Kishimoto, Tomoe; Kisielewska, Danuta; Kiss, Florian; Kitamura, Takumi; Kittelmann, Thomas; Kiuchi, Kenji; Kladiva, Eduard; Klein, Max; Klein, Uta; Kleinknecht, Konrad; Klimek, Pawel; Klimentov, Alexei; Klingenberg, Reiner; Klinger, Joel Alexander; Klioutchnikova, Tatiana; Klok, Peter; Kluge, Eike-Erik; Kluit, Peter; Kluth, Stefan; Kneringer, Emmerich; Knoops, Edith; Knue, Andrea; Kobayashi, Tomio; Kobel, Michael; Kocian, Martin; Kodys, Peter; Koevesarki, Peter; Koffas, Thomas; Koffeman, Els; Kogan, Lucy Anne; Kohlmann, Simon; Kohout, Zdenek; Kohriki, Takashi; Koi, Tatsumi; Kolanoski, Hermann; Koletsou, Iro; Koll, James; Komar, Aston; Komori, Yuto; Kondo, Takahiko; Kondrashova, Nataliia; Köneke, Karsten; König, Adriaan; König, Sebastian; Kono, Takanori; Konoplich, Rostislav; Konstantinidis, Nikolaos; Kopeliansky, Revital; Koperny, Stefan; Köpke, Lutz; Kopp, Anna Katharina; Korcyl, Krzysztof; Kordas, Kostantinos; Korn, Andreas; Korol, Aleksandr; Korolkov, Ilya; Korolkova, Elena; Korotkov, Vladislav; Kortner, Oliver; Kortner, Sandra; Kostyukhin, Vadim; Kotov, Sergey; Kotov, Vladislav; Kotwal, Ashutosh; Kourkoumelis, Christine; Kouskoura, Vasiliki; Koutsman, Alex; Kowalewski, Robert Victor; Kowalski, Tadeusz; Kozanecki, Witold; Kozhin, Anatoly; Kral, Vlastimil; Kramarenko, Viktor; Kramberger, Gregor; Krasnopevtsev, Dimitriy; Krasny, Mieczyslaw Witold; Krasznahorkay, Attila; Kraus, Jana; Kravchenko, Anton; Kreiss, Sven; Kretz, Moritz; Kretzschmar, Jan; Kreutzfeldt, Kristof; Krieger, Peter; Kroeninger, Kevin; Kroha, Hubert; Kroll, Joe; Kroseberg, Juergen; Krstic, Jelena; Kruchonak, Uladzimir; Krüger, Hans; Kruker, Tobias; Krumnack, Nils; Krumshteyn, Zinovii; Kruse, Amanda; Kruse, Mark; Kruskal, Michael; Kubik, Petr; Kubota, Takashi; Kuday, Sinan; Kuehn, Susanne; Kugel, Andreas; Kuhl, Andrew; Kuhl, Thorsten; Kukhtin, Victor; Kulchitsky, Yuri; Kuleshov, Sergey; Kuna, Marine; Kunkle, Joshua; Kupco, Alexander; Kurashige, Hisaya; Kurochkin, Yurii; Kurumida, Rie; Kus, Vlastimil; Kuwertz, Emma Sian; Kuze, Masahiro; Kvita, Jiri; La Rosa, Alessandro; La Rotonda, Laura; Lacasta, Carlos; Lacava, Francesco; Lacey, James; Lacker, Heiko; Lacour, Didier; Lacuesta, Vicente Ramón; Ladygin, Evgueni; Lafaye, Remi; Laforge, Bertrand; Lagouri, Theodota; Lai, Stanley; Laier, Heiko; Lambourne, Luke; Lammers, Sabine; Lampen, Caleb; Lampl, Walter; Lançon, Eric; Landgraf, Ulrich; Landon, Murrough; Lang, Valerie Susanne; Lange, Clemens; Lankford, Andrew; Lanni, Francesco; Lantzsch, Kerstin; Laplace, Sandrine; Lapoire, Cecile; Laporte, Jean-Francois; Lari, Tommaso; Lassnig, Mario; Laurelli, Paolo; Lavrijsen, Wim; Law, Alexander; Laycock, Paul; Le, Bao Tran; Le Dortz, Olivier; Le Guirriec, Emmanuel; Le Menedeu, Eve; LeCompte, Thomas; Ledroit-Guillon, Fabienne Agnes Marie; Lee, Claire, Alexandra; Lee, Hurng-Chun; Lee, Jason; Lee, Shih-Chang; Lee, Lawrence; Lefebvre, Guillaume; Lefebvre, Michel; Legger, Federica; Leggett, Charles; Lehan, Allan; Lehmacher, Marc; Lehmann Miotto, Giovanna; Lei, Xiaowen; Leister, Andrew Gerard; Leite, Marco Aurelio Lisboa; Leitner, Rupert; Lellouch, Daniel; Lemmer, Boris; Leney, Katharine; Lenz, Tatjana; Lenzen, Georg; Lenzi, Bruno; Leone, Robert; Leonhardt, Kathrin; Leontsinis, Stefanos; Leroy, Claude; Lester, Christopher; Lester, Christopher Michael; Levchenko, Mikhail; Levêque, Jessica; Levin, Daniel; Levinson, Lorne; Levy, Mark; Lewis, Adrian; Lewis, George; Leyko, Agnieszka; Leyton, Michael; Li, Bing; Li, Bo; Li, Haifeng; Li, Ho Ling; Li, Liang; Li, Shu; Li, Yichen; Liang, Zhijun; Liao, Hongbo; Liberti, Barbara; Lichard, Peter; Lie, Ki; Liebal, Jessica; Liebig, Wolfgang; Limbach, Christian; Limosani, Antonio; Limper, Maaike; Lin, Simon; Linde, Frank; Lindquist, Brian Edward; Linnemann, James; Lipeles, Elliot; Lipniacka, Anna; Lisovyi, Mykhailo; Liss, Tony; Lissauer, David; Lister, Alison; Litke, Alan; Liu, Bo; Liu, Dong; Liu, Jianbei; Liu, Kun; Liu, Lulu; Liu, Miaoyuan; Liu, Minghui; Liu, Yanwen; Livan, Michele; Livermore, Sarah; Lleres, Annick; Llorente Merino, Javier; Lloyd, Stephen; Lo Sterzo, Francesco; Lobodzinska, Ewelina; Loch, Peter; Lockman, William; Loddenkoetter, Thomas; Loebinger, Fred; Loevschall-Jensen, Ask Emil; Loginov, Andrey; Loh, Chang Wei; Lohse, Thomas; Lohwasser, Kristin; Lokajicek, Milos; Lombardo, Vincenzo Paolo; Long, Brian Alexander; Long, Jonathan; Long, Robin Eamonn; Lopes, Lourenco; Lopez Mateos, David; Lopez Paredes, Brais; Lorenz, Jeanette; Lorenzo Martinez, Narei; Losada, Marta; Loscutoff, Peter; Lou, XinChou; Lounis, Abdenour; Love, Jeremy; Love, Peter; Lowe, Andrew; Lu, Feng; Lubatti, Henry; Luci, Claudio; Lucotte, Arnaud; Luehring, Frederick; Lukas, Wolfgang; Luminari, Lamberto; Lundberg, Olof; Lund-Jensen, Bengt; Lungwitz, Matthias; Lynn, David; Lysak, Roman; Lytken, Else; Ma, Hong; Ma, Lian Liang; Maccarrone, Giovanni; Macchiolo, Anna; Machado Miguens, Joana; Macina, Daniela; Madaffari, Daniele; Madar, Romain; Maddocks, Harvey Jonathan; Mader, Wolfgang; Madsen, Alexander; Maeno, Mayuko; Maeno, Tadashi; Magradze, Erekle; Mahboubi, Kambiz; Mahlstedt, Joern; Mahmoud, Sara; Maiani, Camilla; Maidantchik, Carmen; Maio, Amélia; Majewski, Stephanie; Makida, Yasuhiro; Makovec, Nikola; Mal, Prolay; Malaescu, Bogdan; Malecki, Pawel; Maleev, Victor; Malek, Fairouz; Mallik, Usha; Malon, David; Malone, Caitlin; Maltezos, Stavros; Malyshev, Vladimir; Malyukov, Sergei; Mamuzic, Judita; Mandelli, Beatrice; Mandelli, Luciano; Mandić, Igor; Mandrysch, Rocco; Maneira, José; Manfredini, Alessandro; Manhaes de Andrade Filho, Luciano; Manjarres Ramos, Joany Andreina; Mann, Alexander; Manning, Peter; Manousakis-Katsikakis, Arkadios; Mansoulie, Bruno; Mantifel, Rodger; Mapelli, Livio; March, Luis; Marchand, Jean-Francois; Marchiori, Giovanni; Marcisovsky, Michal; Marino, Christopher; Marques, Carlos; Marroquim, Fernando; Marsden, Stephen Philip; Marshall, Zach; Marti, Lukas Fritz; Marti-Garcia, Salvador; Martin, Brian; Martin, Brian; Martin, Jean-Pierre; Martin, Tim; Martin, Victoria Jane; Martin dit Latour, Bertrand; Martinez, Homero; Martinez, Mario; Martin-Haugh, Stewart; Martyniuk, Alex; Marx, Marilyn; Marzano, Francesco; Marzin, Antoine; Masetti, Lucia; Mashimo, Tetsuro; Mashinistov, Ruslan; Masik, Jiri; Maslennikov, Alexey; Massa, Ignazio; Massol, Nicolas; Mastrandrea, Paolo; Mastroberardino, Anna; Masubuchi, Tatsuya; Matricon, Pierre; Matsunaga, Hiroyuki; Matsushita, Takashi; Mättig, Peter; Mättig, Stefan; Mattmann, Johannes; Maurer, Julien; Maxfield, Stephen; Maximov, Dmitriy; Mazini, Rachid; Mazzaferro, Luca; Mc Goldrick, Garrin; Mc Kee, Shawn Patrick; McCarn, Allison; McCarthy, Robert; McCarthy, Tom; McCubbin, Norman; McFarlane, Kenneth; Mcfayden, Josh; Mchedlidze, Gvantsa; Mclaughlan, Tom; McMahon, Steve; McPherson, Robert; Meade, Andrew; Mechnich, Joerg; Medinnis, Michael; Meehan, Samuel; Mehlhase, Sascha; Mehta, Andrew; Meier, Karlheinz; Meineck, Christian; Meirose, Bernhard; Melachrinos, Constantinos; Mellado Garcia, Bruce Rafael; Meloni, Federico; Mengarelli, Alberto; Menke, Sven; Meoni, Evelin; Mercurio, Kevin Michael; Mergelmeyer, Sebastian; Meric, Nicolas; Mermod, Philippe; Merola, Leonardo; Meroni, Chiara; Merritt, Frank; Merritt, Hayes; Messina, Andrea; Metcalfe, Jessica; Mete, Alaettin Serhan; Meyer, Carsten; Meyer, Christopher; Meyer, Jean-Pierre; Meyer, Jochen; Middleton, Robin; Migas, Sylwia; Mijović, Liza; Mikenberg, Giora; Mikestikova, Marcela; Mikuž, Marko; Miller, David; Mills, Corrinne; Milov, Alexander; Milstead, David; Milstein, Dmitry; Minaenko, Andrey; Miñano Moya, Mercedes; Minashvili, Irakli; Mincer, Allen; Mindur, Bartosz; Mineev, Mikhail; Ming, Yao; Mir, Lluisa-Maria; Mirabelli, Giovanni; Mitani, Takashi; Mitrevski, Jovan; Mitsou, Vasiliki A; Mitsui, Shingo; Miucci, Antonio; Miyagawa, Paul; Mjörnmark, Jan-Ulf; Moa, Torbjoern; Mochizuki, Kazuya; Moeller, Victoria; Mohapatra, Soumya; Mohr, Wolfgang; Molander, Simon; Moles-Valls, Regina; Mönig, Klaus; Monini, Caterina; Monk, James; Monnier, Emmanuel; Montejo Berlingen, Javier; Monticelli, Fernando; Monzani, Simone; Moore, Roger; Moraes, Arthur; Morange, Nicolas; Morel, Julien; Moreno, Deywis; Moreno Llácer, María; Morettini, Paolo; Morgenstern, Marcus; Morii, Masahiro; Moritz, Sebastian; Morley, Anthony Keith; Mornacchi, Giuseppe; Morris, John; Morvaj, Ljiljana; Moser, Hans-Guenther; Mosidze, Maia; Moss, Josh; Mount, Richard; Mountricha, Eleni; Mouraviev, Sergei; Moyse, Edward; Muanza, Steve; Mudd, Richard; Mueller, Felix; Mueller, James; Mueller, Klemens; Mueller, Thibaut; Mueller, Timo; Muenstermann, Daniel; Munwes, Yonathan; Murillo Quijada, Javier Alberto; Murray, Bill; Musheghyan, Haykuhi; Musto, Elisa; Myagkov, Alexey; Myska, Miroslav; Nackenhorst, Olaf; Nadal, Jordi; Nagai, Koichi; Nagai, Ryo; Nagai, Yoshikazu; Nagano, Kunihiro; Nagarkar, Advait; Nagasaka, Yasushi; Nagel, Martin; Nairz, Armin Michael; Nakahama, Yu; Nakamura, Koji; Nakamura, Tomoaki; Nakano, Itsuo; Namasivayam, Harisankar; Nanava, Gizo; Narayan, Rohin; Nattermann, Till; Naumann, Thomas; Navarro, Gabriela; Nayyar, Ruchika; Neal, Homer; Nechaeva, Polina; Neep, Thomas James; Negri, Andrea; Negri, Guido; Negrini, Matteo; Nektarijevic, Snezana; Nelson, Andrew; Nelson, Timothy Knight; Nemecek, Stanislav; Nemethy, Peter; Nepomuceno, Andre Asevedo; Nessi, Marzio; Neubauer, Mark; Neumann, Manuel; Neves, Ricardo; Nevski, Pavel; Newcomer, Mitchel; Newman, Paul; Nguyen, Duong Hai; Nickerson, Richard; Nicolaidou, Rosy; Nicquevert, Bertrand; Nielsen, Jason; Nikiforou, Nikiforos; Nikiforov, Andriy; Nikolaenko, Vladimir; Nikolic-Audit, Irena; Nikolics, Katalin; Nikolopoulos, Konstantinos; Nilsson, Paul; Ninomiya, Yoichi; Nisati, Aleandro; Nisius, Richard; Nobe, Takuya; Nodulman, Lawrence; Nomachi, Masaharu; Nomidis, Ioannis; Norberg, Scarlet; Nordberg, Markus; Nowak, Sebastian; Nozaki, Mitsuaki; Nozka, Libor; Ntekas, Konstantinos; Nunes Hanninger, Guilherme; Nunnemann, Thomas; Nurse, Emily; Nuti, Francesco; O'Brien, Brendan Joseph; O'grady, Fionnbarr; O'Neil, Dugan; O'Shea, Val; Oakham, Gerald; Oberlack, Horst; Obermann, Theresa; Ocariz, Jose; Ochi, Atsuhiko; Ochoa, Ines; Oda, Susumu; Odaka, Shigeru; Ogren, Harold; Oh, Alexander; Oh, Seog; Ohm, Christian; Ohman, Henrik; Ohshima, Takayoshi; Okamura, Wataru; Okawa, Hideki; Okumura, Yasuyuki; Okuyama, Toyonobu; Olariu, Albert; Olchevski, Alexander; Olivares Pino, Sebastian Andres; Oliveira Damazio, Denis; Oliver Garcia, Elena; Olszewski, Andrzej; Olszowska, Jolanta; Onofre, António; Onyisi, Peter; Oram, Christopher; Oreglia, Mark; Oren, Yona; Orestano, Domizia; Orlando, Nicola; Oropeza Barrera, Cristina; Orr, Robert; Osculati, Bianca; Ospanov, Rustem; Otero y Garzon, Gustavo; Otono, Hidetoshi; Ouchrif, Mohamed; Ouellette, Eric; Ould-Saada, Farid; Ouraou, Ahmimed; Oussoren, Koen Pieter; Ouyang, Qun; Ovcharova, Ana; Owen, Mark; Ozcan, Veysi Erkcan; Ozturk, Nurcan; Pachal, Katherine; Pacheco Pages, Andres; Padilla Aranda, Cristobal; Pagáčová, Martina; Pagan Griso, Simone; Paganis, Efstathios; Pahl, Christoph; Paige, Frank; Pais, Preema; Pajchel, Katarina; Palacino, Gabriel; Palestini, Sandro; Pallin, Dominique; Palma, Alberto; Palmer, Jody; Pan, Yibin; Panagiotopoulou, Evgenia; Panduro Vazquez, William; Pani, Priscilla; Panikashvili, Natalia; Panitkin, Sergey; Pantea, Dan; Paolozzi, Lorenzo; Papadopoulou, Theodora; Papageorgiou, Konstantinos; Paramonov, Alexander; Paredes Hernandez, Daniela; Parker, Michael Andrew; Parodi, Fabrizio; Parsons, John; Parzefall, Ulrich; Pasqualucci, Enrico; Passaggio, Stefano; Passeri, Antonio; Pastore, Fernanda; Pastore, Francesca; Pásztor, Gabriella; Pataraia, Sophio; Patel, Nikhul; Pater, Joleen; Patricelli, Sergio; Pauly, Thilo; Pearce, James; Pedersen, Maiken; Pedraza Lopez, Sebastian; Pedro, Rute; Peleganchuk, Sergey; Pelikan, Daniel; Peng, Haiping; Penning, Bjoern; Penwell, John; Perepelitsa, Dennis; Perez Codina, Estel; Pérez García-Estañ, María Teresa; Perez Reale, Valeria; Perini, Laura; Pernegger, Heinz; Perrino, Roberto; Peschke, Richard; Peshekhonov, Vladimir; Peters, Krisztian; Peters, Yvonne; Petersen, Brian; Petersen, Jorgen; Petersen, Troels; Petit, Elisabeth; Petridis, Andreas; Petridou, Chariclia; Petrolo, Emilio; Petrucci, Fabrizio; Petteni, Michele; Pettersson, Nora Emilia; Pezoa, Raquel; Phillips, Peter William; Piacquadio, Giacinto; Pianori, Elisabetta; Picazio, Attilio; Piccaro, Elisa; Piccinini, Maurizio; Piegaia, Ricardo; Pieron, Jacek Piotr; Pignotti, David; Pilcher, James; Pilkington, Andrew; Pina, João Antonio; Pinamonti, Michele; Pinder, Alex; Pinfold, James; Pingel, Almut; Pinto, Belmiro; Pires, Sylvestre; Pitt, Michael; Pizio, Caterina; Pleier, Marc-Andre; Pleskot, Vojtech; Plotnikova, Elena; Plucinski, Pawel; Poddar, Sahill; Podlyski, Fabrice; Poettgen, Ruth; Poggioli, Luc; Pohl, David-leon; Pohl, Martin; Polesello, Giacomo; Policicchio, Antonio; Polifka, Richard; Polini, Alessandro; Pollard, Christopher Samuel; Polychronakos, Venetios; Pommès, Kathy; Pontecorvo, Ludovico; Pope, Bernard; Popeneciu, Gabriel Alexandru; Popovic, Dragan; Poppleton, Alan; Portell Bueso, Xavier; Pospelov, Guennady; Pospisil, Stanislav; Potamianos, Karolos; Potrap, Igor; Potter, Christina; Potter, Christopher; Poulard, Gilbert; Poveda, Joaquin; Pozdnyakov, Valery; Pralavorio, Pascal; Pranko, Aliaksandr; Prasad, Srivas; Pravahan, Rishiraj; Prell, Soeren; Price, Darren; Price, Joe; Price, Lawrence; Prieur, Damien; Primavera, Margherita; Proissl, Manuel; Prokofiev, Kirill; Prokoshin, Fedor; Protopapadaki, Eftychia-sofia; Protopopescu, Serban; Proudfoot, James; Przybycien, Mariusz; Przysiezniak, Helenka; Ptacek, Elizabeth; Pueschel, Elisa; Puldon, David; Purohit, Milind; Puzo, Patrick; Qian, Jianming; Qin, Gang; Qin, Yang; Quadt, Arnulf; Quarrie, David; Quayle, William; Quilty, Donnchadha; Qureshi, Anum; Radeka, Veljko; Radescu, Voica; Radhakrishnan, Sooraj Krishnan; Radloff, Peter; Rados, Pere; Ragusa, Francesco; Rahal, Ghita; Rajagopalan, Srinivasan; Rammensee, Michael; Randle-Conde, Aidan Sean; Rangel-Smith, Camila; Rao, Kanury; Rauscher, Felix; Rave, Tobias Christian; Ravenscroft, Thomas; Raymond, Michel; Read, Alexander Lincoln; Rebuzzi, Daniela; Redelbach, Andreas; Redlinger, George; Reece, Ryan; Reeves, Kendall; Rehnisch, Laura; Reinsch, Andreas; Reisin, Hernan; Relich, Matthew; Rembser, Christoph; Ren, Zhongliang; Renaud, Adrien; Rescigno, Marco; Resconi, Silvia; Resende, Bernardo; Rezanova, Olga; Reznicek, Pavel; Rezvani, Reyhaneh; Richter, Robert; Ridel, Melissa; Rieck, Patrick; Rijssenbeek, Michael; Rimoldi, Adele; Rinaldi, Lorenzo; Ritsch, Elmar; Riu, Imma; Rizatdinova, Flera; Rizvi, Eram; Robertson, Steven; Robichaud-Veronneau, Andree; Robinson, Dave; Robinson, James; Robson, Aidan; Roda, Chiara; Rodrigues, Luis; Roe, Shaun; Røhne, Ole; Rolli, Simona; Romaniouk, Anatoli; Romano, Marino; Romeo, Gaston; Romero Adam, Elena; Rompotis, Nikolaos; Roos, Lydia; Ros, Eduardo; Rosati, Stefano; Rosbach, Kilian; Rose, Matthew; Rosendahl, Peter Lundgaard; Rosenthal, Oliver; Rossetti, Valerio; Rossi, Elvira; Rossi, Leonardo Paolo; Rosten, Rachel; Rotaru, Marina; Roth, Itamar; Rothberg, Joseph; Rousseau, David; Royon, Christophe; Rozanov, Alexandre; Rozen, Yoram; Ruan, Xifeng; Rubbo, Francesco; Rubinskiy, Igor; Rud, Viacheslav; Rudolph, Christian; Rudolph, Matthew Scott; Rühr, Frederik; Ruiz-Martinez, Aranzazu; Rurikova, Zuzana; Rusakovich, Nikolai; Ruschke, Alexander; Rutherfoord, John; Ruthmann, Nils; Ryabov, Yury; Rybar, Martin; Rybkin, Grigori; Ryder, Nick; Saavedra, Aldo; Sacerdoti, Sabrina; Saddique, Asif; Sadeh, Iftach; Sadrozinski, Hartmut; Sadykov, Renat; Safai Tehrani, Francesco; Sakamoto, Hiroshi; Sakurai, Yuki; Salamanna, Giuseppe; Salamon, Andrea; Saleem, Muhammad; Salek, David; Sales De Bruin, Pedro Henrique; Salihagic, Denis; Salnikov, Andrei; Salt, José; Salvachua Ferrando, Belén; Salvatore, Daniela; Salvatore, Pasquale Fabrizio; Salvucci, Antonio; Salzburger, Andreas; Sampsonidis, Dimitrios; Sanchez, Arturo; Sánchez, Javier; Sanchez Martinez, Victoria; Sandaker, Heidi; Sandbach, Ruth Laura; Sander, Heinz Georg; Sanders, Michiel; Sandhoff, Marisa; Sandoval, Tanya; Sandoval, Carlos; Sandstroem, Rikard; Sankey, Dave; Sansoni, Andrea; Santoni, Claudio; Santonico, Rinaldo; Santos, Helena; Santoyo Castillo, Itzebelt; Sapp, Kevin; Sapronov, Andrey; Saraiva, João; Sarrazin, Bjorn; Sartisohn, Georg; Sasaki, Osamu; Sasaki, Yuichi; Satsounkevitch, Igor; Sauvage, Gilles; Sauvan, Emmanuel; Savard, Pierre; Savu, Dan Octavian; Sawyer, Craig; Sawyer, Lee; Saxon, James; Sbarra, Carla; Sbrizzi, Antonio; Scanlon, Tim; Scannicchio, Diana; Scarcella, Mark; Schaarschmidt, Jana; Schacht, Peter; Schaefer, Douglas; Schaefer, Ralph; Schaepe, Steffen; Schaetzel, Sebastian; Schäfer, Uli; Schaffer, Arthur; Schaile, Dorothee; Schamberger, R. Dean; Scharf, Veit; Schegelsky, Valery; Scheirich, Daniel; Schernau, Michael; Scherzer, Max; Schiavi, Carlo; Schieck, Jochen; Schillo, Christian; Schioppa, Marco; Schlenker, Stefan; Schmidt, Evelyn; Schmieden, Kristof; Schmitt, Christian; Schmitt, Christopher; Schmitt, Sebastian; Schneider, Basil; Schnellbach, Yan Jie; Schnoor, Ulrike; Schoeffel, Laurent; Schoening, Andre; Schoenrock, Bradley Daniel; Schorlemmer, Andre Lukas; Schott, Matthias; Schouten, Doug; Schovancova, Jaroslava; Schram, Malachi; Schramm, Steven; Schreyer, Manuel; Schroeder, Christian; Schuh, Natascha; Schultens, Martin Johannes; Schultz-Coulon, Hans-Christian; Schulz, Holger; Schumacher, Markus; Schumm, Bruce; Schune, Philippe; Schwartzman, Ariel; Schwegler, Philipp; Schwemling, Philippe; Schwienhorst, Reinhard; Schwindling, Jerome; Schwindt, Thomas; Schwoerer, Maud; Sciacca, Gianfranco; Scifo, Estelle; Sciolla, Gabriella; Scott, Bill; Scuri, Fabrizio; Scutti, Federico; Searcy, Jacob; Sedov, George; Sedykh, Evgeny; Seidel, Sally; Seiden, Abraham; Seifert, Frank; Seixas, José; Sekhniaidze, Givi; Sekula, Stephen; Selbach, Karoline Elfriede; Seliverstov, Dmitry; Sellers, Graham; Semprini-Cesari, Nicola; Serfon, Cedric; Serin, Laurent; Serkin, Leonid; Serre, Thomas; Seuster, Rolf; Severini, Horst; Sforza, Federico; Sfyrla, Anna; Shabalina, Elizaveta; Shamim, Mansoora; Shan, Lianyou; Shank, James; Shao, Qi Tao; Shapiro, Marjorie; Shatalov, Pavel; Shaw, Kate; Shaw, Rick; Sherwood, Peter; Shimizu, Shima; Shimmin, Chase Owen; Shimojima, Makoto; Shiyakova, Mariya; Shmeleva, Alevtina; Shochet, Mel; Short, Daniel; Shrestha, Suyog; Shulga, Evgeny; Shupe, Michael; Shushkevich, Stanislav; Sicho, Petr; Sidorov, Dmitri; Sidoti, Antonio; Siegert, Frank; Sijacki, Djordje; Silbert, Ohad; Silva, José; Silver, Yiftah; Silverstein, Daniel; Silverstein, Samuel; Simak, Vladislav; Simard, Olivier; Simic, Ljiljana; Simion, Stefan; Simioni, Eduard; Simmons, Brinick; Simoniello, Rosa; Simonyan, Margar; Sinervo, Pekka; Sinev, Nikolai; Sipica, Valentin; Siragusa, Giovanni; Sircar, Anirvan; Sisakyan, Alexei; Sivoklokov, Serguei; Sjölin, Jörgen; Sjursen, Therese; Skottowe, Hugh Philip; Skovpen, Kirill; Skubic, Patrick; Slater, Mark; Slavicek, Tomas; Sliwa, Krzysztof; Smakhtin, Vladimir; Smart, Ben; Smestad, Lillian; Smirnov, Sergei; Smirnov, Yury; Smirnova, Lidia; Smirnova, Oxana; Smizanska, Maria; Smolek, Karel; Snesarev, Andrei; Snidero, Giacomo; Snow, Joel; Snyder, Scott; Sobie, Randall; Socher, Felix; Sodomka, Jaromir; Soffer, Abner; Soh, Dart-yin; Solans, Carlos; Solar, Michael; Solc, Jaroslav; Soldatov, Evgeny; Soldevila, Urmila; Solfaroli Camillocci, Elena; Solodkov, Alexander; Solovyanov, Oleg; Solovyev, Victor; Sommer, Philip; Song, Hong Ye; Soni, Nitesh; Sood, Alexander; Sopczak, Andre; Sopko, Vit; Sopko, Bruno; Sorin, Veronica; Sosebee, Mark; Soualah, Rachik; Soueid, Paul; Soukharev, Andrey; South, David; Spagnolo, Stefania; Spanò, Francesco; Spearman, William Robert; Spighi, Roberto; Spigo, Giancarlo; Spousta, Martin; Spreitzer, Teresa; Spurlock, Barry; St Denis, Richard Dante; Staerz, Steffen; Stahlman, Jonathan; Stamen, Rainer; Stanecka, Ewa; Stanek, Robert; Stanescu, Cristian; Stanescu-Bellu, Madalina; Stanitzki, Marcel Michael; Stapnes, Steinar; Starchenko, Evgeny; Stark, Jan; Staroba, Pavel; Starovoitov, Pavel; Staszewski, Rafal; Stavina, Pavel; Steele, Genevieve; Steinberg, Peter; Stekl, Ivan; Stelzer, Bernd; Stelzer, Harald Joerg; Stelzer-Chilton, Oliver; Stenzel, Hasko; Stern, Sebastian; Stewart, Graeme; Stillings, Jan Andre; Stockton, Mark; Stoebe, Michael; Stoicea, Gabriel; Stolte, Philipp; Stonjek, Stefan; Stradling, Alden; Straessner, Arno; Stramaglia, Maria Elena; Strandberg, Jonas; Strandberg, Sara; Strandlie, Are; Strauss, Emanuel; Strauss, Michael; Strizenec, Pavol; Ströhmer, Raimund; Strom, David; Stroynowski, Ryszard; Stucci, Stefania Antonia; Stugu, Bjarne; Styles, Nicholas Adam; Su, Dong; Su, Jun; Subramania, Halasya Siva; Subramaniam, Rajivalochan; Succurro, Antonella; Sugaya, Yorihito; Suhr, Chad; Suk, Michal; Sulin, Vladimir; Sultansoy, Saleh; Sumida, Toshi; Sun, Xiaohu; Sundermann, Jan Erik; Suruliz, Kerim; Susinno, Giancarlo; Sutton, Mark; Suzuki, Yu; Svatos, Michal; Swedish, Stephen; Swiatlowski, Maximilian; Sykora, Ivan; Sykora, Tomas; Ta, Duc; Tackmann, Kerstin; Taenzer, Joe; Taffard, Anyes; Tafirout, Reda; Taiblum, Nimrod; Takahashi, Yuta; Takai, Helio; Takashima, Ryuichi; Takeda, Hiroshi; Takeshita, Tohru; Takubo, Yosuke; Talby, Mossadek; Talyshev, Alexey; Tam, Jason; Tamsett, Matthew; Tan, Kong Guan; Tanaka, Junichi; Tanaka, Reisaburo; Tanaka, Satoshi; Tanaka, Shuji; Tanasijczuk, Andres Jorge; Tani, Kazutoshi; Tannoury, Nancy; Tapprogge, Stefan; Tarem, Shlomit; Tarrade, Fabien; Tartarelli, Giuseppe Francesco; Tas, Petr; Tasevsky, Marek; Tashiro, Takuya; Tassi, Enrico; Tavares Delgado, Ademar; Tayalati, Yahya; Taylor, Frank; Taylor, Geoffrey; Taylor, Wendy; Teischinger, Florian Alfred; Teixeira Dias Castanheira, Matilde; Teixeira-Dias, Pedro; Temming, Kim Katrin; Ten Kate, Herman; Teng, Ping-Kun; Terada, Susumu; Terashi, Koji; Terron, Juan; Terzo, Stefano; Testa, Marianna; Teuscher, Richard; Therhaag, Jan; Theveneaux-Pelzer, Timothée; Thoma, Sascha; Thomas, Juergen; Thomas-Wilsker, Joshuha; Thompson, Emily; Thompson, Paul; Thompson, Peter; Thompson, Stan; Thomsen, Lotte Ansgaard; Thomson, Evelyn; Thomson, Mark; Thong, Wai Meng; Thun, Rudolf; Tian, Feng; Tibbetts, Mark James; Tikhomirov, Vladimir; Tikhonov, Yury; Timoshenko, Sergey; Tiouchichine, Elodie; Tipton, Paul; Tisserant, Sylvain; Todorov, Theodore; Todorova-Nova, Sharka; Toggerson, Brokk; Tojo, Junji; Tokár, Stanislav; Tokushuku, Katsuo; Tollefson, Kirsten; Tomlinson, Lee; Tomoto, Makoto; Tompkins, Lauren; Toms, Konstantin; Topilin, Nikolai; Torrence, Eric; Torres, Heberth; Torró Pastor, Emma; Toth, Jozsef; Touchard, Francois; Tovey, Daniel; Tran, Huong Lan; Trefzger, Thomas; Tremblet, Louis; Tricoli, Alessandro; Trigger, Isabel Marian; Trincaz-Duvoid, Sophie; Tripiana, Martin; Triplett, Nathan; Trischuk, William; Trocmé, Benjamin; Troncon, Clara; Trottier-McDonald, Michel; Trovatelli, Monica; True, Patrick; Trzebinski, Maciej; Trzupek, Adam; Tsarouchas, Charilaos; Tseng, Jeffrey; Tsiareshka, Pavel; Tsionou, Dimitra; Tsipolitis, Georgios; Tsirintanis, Nikolaos; Tsiskaridze, Shota; Tsiskaridze, Vakhtang; Tskhadadze, Edisher; Tsukerman, Ilya; Tsulaia, Vakhtang; Tsuno, Soshi; Tsybychev, Dmitri; Tudorache, Alexandra; Tudorache, Valentina; Tuna, Alexander Naip; Tupputi, Salvatore; Turchikhin, Semen; Turecek, Daniel; Turk Cakir, Ilkay; Turra, Ruggero; Tuts, Michael; Tykhonov, Andrii; Tylmad, Maja; Tyndel, Mike; Uchida, Kirika; Ueda, Ikuo; Ueno, Ryuichi; Ughetto, Michael; Ugland, Maren; Uhlenbrock, Mathias; Ukegawa, Fumihiko; Unal, Guillaume; Undrus, Alexander; Unel, Gokhan; Ungaro, Francesca; Unno, Yoshinobu; Urbaniec, Dustin; Urquijo, Phillip; Usai, Giulio; Usanova, Anna; Vacavant, Laurent; Vacek, Vaclav; Vachon, Brigitte; Valencic, Nika; Valentinetti, Sara; Valero, Alberto; Valery, Loic; Valkar, Stefan; Valladolid Gallego, Eva; Vallecorsa, Sofia; Valls Ferrer, Juan Antonio; Van Berg, Richard; Van Der Deijl, Pieter; van der Geer, Rogier; van der Graaf, Harry; Van Der Leeuw, Robin; van der Ster, Daniel; van Eldik, Niels; van Gemmeren, Peter; Van Nieuwkoop, Jacobus; van Vulpen, Ivo; van Woerden, Marius Cornelis; Vanadia, Marco; Vandelli, Wainer; Vanguri, Rami; Vaniachine, Alexandre; Vankov, Peter; Vannucci, Francois; Vardanyan, Gagik; Vari, Riccardo; Varnes, Erich; Varol, Tulin; Varouchas, Dimitris; Vartapetian, Armen; Varvell, Kevin; Vazeille, Francois; Vazquez Schroeder, Tamara; Veatch, Jason; Veloso, Filipe; Veneziano, Stefano; Ventura, Andrea; Ventura, Daniel; Venturi, Manuela; Venturi, Nicola; Venturini, Alessio; Vercesi, Valerio; Verducci, Monica; Verkerke, Wouter; Vermeulen, Jos; Vest, Anja; Vetterli, Michel; Viazlo, Oleksandr; Vichou, Irene; Vickey, Trevor; Vickey Boeriu, Oana Elena; Viehhauser, Georg; Viel, Simon; Vigne, Ralph; Villa, Mauro; Villaplana Perez, Miguel; Vilucchi, Elisabetta; Vincter, Manuella; Vinogradov, Vladimir; Virzi, Joseph; Vivarelli, Iacopo; Vives Vaque, Francesc; Vlachos, Sotirios; Vladoiu, Dan; Vlasak, Michal; Vogel, Adrian; Vokac, Petr; Volpi, Guido; Volpi, Matteo; von der Schmitt, Hans; von Radziewski, Holger; von Toerne, Eckhard; Vorobel, Vit; Vorobev, Konstantin; Vos, Marcel; Voss, Rudiger; Vossebeld, Joost; Vranjes, Nenad; Vranjes Milosavljevic, Marija; Vrba, Vaclav; Vreeswijk, Marcel; Vu Anh, Tuan; Vuillermet, Raphael; Vukotic, Ilija; Vykydal, Zdenek; Wagner, Wolfgang; Wagner, Peter; Wahrmund, Sebastian; Wakabayashi, Jun; Walder, James; Walker, Rodney; Walkowiak, Wolfgang; Wall, Richard; Waller, Peter; Walsh, Brian; Wang, Chao; Wang, Chiho; Wang, Fuquan; Wang, Haichen; Wang, Hulin; Wang, Jike; Wang, Jin; Wang, Kuhan; Wang, Rui; Wang, Song-Ming; Wang, Tan; Wang, Xiaoxiao; Wanotayaroj, Chaowaroj; Warburton, Andreas; Ward, Patricia; Wardrope, David Robert; Warren, Matthew; Warsinsky, Markus; Washbrook, Andrew; Wasicki, Christoph; Watanabe, Ippei; Watkins, Peter; Watson, Alan; Watson, Ian; Watson, Miriam; Watts, Gordon; Watts, Stephen; Waugh, Ben; Webb, Samuel; Weber, Michele; Weber, Stefan Wolf; Webster, Jordan S; Weidberg, Anthony; Weigell, Philipp; Weinert, Benjamin; Weingarten, Jens; Weiser, Christian; Weits, Hartger; Wells, Phillippa; Wenaus, Torre; Wendland, Dennis; Weng, Zhili; Wengler, Thorsten; Wenig, Siegfried; Wermes, Norbert; Werner, Matthias; Werner, Per; Wessels, Martin; Wetter, Jeffrey; Whalen, Kathleen; White, Andrew; White, Martin; White, Ryan; White, Sebastian; Whiteson, Daniel; Wicke, Daniel; Wickens, Fred; Wiedenmann, Werner; Wielers, Monika; Wienemann, Peter; Wiglesworth, Craig; Wiik-Fuchs, Liv Antje Mari; Wijeratne, Peter Alexander; Wildauer, Andreas; Wildt, Martin Andre; Wilkens, Henric George; Will, Jonas Zacharias; Williams, Hugh; Williams, Sarah; Willis, Christopher; Willocq, Stephane; Wilson, John; Wilson, Alan; Wingerter-Seez, Isabelle; Winklmeier, Frank; Wittgen, Matthias; Wittig, Tobias; Wittkowski, Josephine; Wollstadt, Simon Jakob; Wolter, Marcin Wladyslaw; Wolters, Helmut; Wosiek, Barbara; Wotschack, Jorg; Woudstra, Martin; Wozniak, Krzysztof; Wright, Michael; Wu, Mengqing; Wu, Sau Lan; Wu, Xin; Wu, Yusheng; Wulf, Evan; Wyatt, Terry Richard; Wynne, Benjamin; Xella, Stefania; Xiao, Meng; Xu, Da; Xu, Lailin; Yabsley, Bruce; Yacoob, Sahal; Yamada, Miho; Yamaguchi, Hiroshi; Yamaguchi, Yohei; Yamamoto, Akira; Yamamoto, Kyoko; Yamamoto, Shimpei; Yamamura, Taiki; Yamanaka, Takashi; Yamauchi, Katsuya; Yamazaki, Yuji; Yan, Zhen; Yang, Haijun; Yang, Hongtao; Yang, Un-Ki; Yang, Yi; Yanush, Serguei; Yao, Liwen; Yao, Weiming; Yasu, Yoshiji; Yatsenko, Elena; Yau Wong, Kaven Henry; Ye, Jingbo; Ye, Shuwei; Yen, Andy L; Yildirim, Eda; Yilmaz, Metin; Yoosoofmiya, Reza; Yorita, Kohei; Yoshida, Rikutaro; Yoshihara, Keisuke; Young, Charles; Young, Christopher John; Youssef, Saul; Yu, David Ren-Hwa; Yu, Jaehoon; Yu, Jiaming; Yu, Jie; Yuan, Li; Yurkewicz, Adam; Zabinski, Bartlomiej; Zaidan, Remi; Zaitsev, Alexander; Zaman, Aungshuman; Zambito, Stefano; Zanello, Lucia; Zanzi, Daniele; Zaytsev, Alexander; Zeitnitz, Christian; Zeman, Martin; Zemla, Andrzej; Zengel, Keith; Zenin, Oleg; Ženiš, Tibor; Zerwas, Dirk; Zevi della Porta, Giovanni; Zhang, Dongliang; Zhang, Fangzhou; Zhang, Huaqiao; Zhang, Jinlong; Zhang, Lei; Zhang, Xueyao; Zhang, Zhiqing; Zhao, Zhengguo; Zhemchugov, Alexey; Zhong, Jiahang; Zhou, Bing; Zhou, Lei; Zhou, Ning; Zhu, Cheng Guang; Zhu, Hongbo; Zhu, Junjie; Zhu, Yingchun; Zhuang, Xuai; Zibell, Andre; Zieminska, Daria; Zimine, Nikolai; Zimmermann, Christoph; Zimmermann, Robert; Zimmermann, Simone; Zimmermann, Stephanie; Zinonos, Zinonas; Ziolkowski, Michael; Zobernig, Georg; Zoccoli, Antonio; zur Nedden, Martin; Zurzolo, Giovanni; Zutshi, Vishnu; Zwalinski, Lukasz

    2014-01-01

    The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74 +/- 0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, delta-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations.

  14. Commissioning and Performance of the LHCb Silicon Tracker

    CERN Multimedia

    van Tilburg, J; Buechler, A; Bursche , A; Chiapolini, N; Elsaesser, C; Hangartner, V; Salzmann, C; Steiner, S; Steinkamp, O; Staumann, U; Tobin, M; Vollhardt, A; Bay, A; Bettler, M O; Blanc, F; Bressieux, J; Conti, G; Fave, V; Frei, R; Gauvin, N; Gonzalez, R; Haefeli, G; Hicheur, A; Keune, A; Luisier, J; Muresan, R; Nakada, T; Needham, M; Nicolas, L; Knecht, M; Perrin, A; Potterat, C; Schneider, O; Tran, M; Aquines Gutierrez, O; Bauer, C; Britsch, M; Hofmann, W; Maciuc, F; Schmelling, M; Voss, H; Adeva, B; Esperante, D; Fungueiriño Pazos, J; Gallas, A; Pazos-Alvarez, A; Pérez-Trigo, E; Pló Casasús, M; Rogríguez Pérez, P; Saborido, J; Vázquez, P; Iakovenko, V; Okhrimenko, O; Pugatch, V

    2010-01-01

    The LHCb Silicon Tracker is a silicon micro-strip detector with a sensitive area of 12 m$^2$ and a total of 272k readout channels. The Silicon Tracker consists of two parts that use different detector modules. The detector installation was completed by early summer 2008 and the commissioning without beam has reached its finals stage, successfully overcoming most of the encountered problems. Currently, the detector has more than 99% of the channels fully functioning. Commissioning with particles has started using beam-induced events from the LHC injection tests in 2008 and 2009. These events allowed initial studies of the detector performance. Especially, the detector modules could be aligned with an accuracy of about 20 $\\mu$m. Furthermore, with the first beam collisions that took place end of 2009 we could further study the performance and improve the alignment of the detector.

  15. CMS Silicon Tracker Module Assembly and Testing at FNAL

    CERN Document Server

    Coppage, Don; Gerber, Cecilia Elena; Kahl, William E; Medel, E; Ronzhin, Anatoly; Sogut, Kenan; Shabalina, Elizaveta; Spiegel, Leonard; Ten, Timour Borisovich

    2005-01-01

    This note is intended to provide details on a recent activity at FNAL in which CMS Tracker Outer Barrel modules were assembled and tested as part of a qualification of some of the sensor fabrication lines. At the same time the note serves to document the assembly and testing operations at FNAL for CMS silicon tracker modules. Of the 88 modules produced fo the qualification study at FNAL, one module was outside the mechanical alignment specification. For module bonding an introduced failure rate of 4.0x10^-4 faults per channel was observed. Eighty-five of the modules passed the full set of electrical tests. Two of the failures could be attributed to the sensors and one to a problem with the front-end hybrid. Additionally, a couple of the passed modules drew unusually high leakage currents. The high current modules are discussed in some detail.

  16. Simultaneous alignment of the CMS silicon tracker using Millepede II

    Energy Technology Data Exchange (ETDEWEB)

    Stefaniuk, Nazar; Mankel, Rainer; Schroeder, Matthias; Kleinwort, Claus; Gizhko, Andrii [Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, Hamburg (Germany)

    2015-07-01

    The CMS tracker is the world's largest silicon detector, consisting of more than 25 000 sensors. A precise knowledge of their positions and orientations is crucial for the physics performance of the whole experiment. Track-based alignment procedure uses minimization of the residuals between the measured and expected hit position in the detector. An accuracy of 10 μm and 10 μrad for the module position and orientation, respectively, is achieved. Both tracks from pp-collision and cosmic-ray data are taken into account. In this way, more than 200 000 alignment parameters, describing the position, rotation and curvature of the sensors are determined simultaneously using the Millepede II program. In the presentation, results of the CMS-tracker alignment with the data collected in 2012 are presented. The sensitivity of the procedure to a certain misalignment scenario is investigated, and foreseen improvements for the upcoming LHC Run-2 are discussed.

  17. Operation and Performance of the CMS Silicon Tracker

    CERN Document Server

    Krammer, Manfred

    2011-01-01

    The presentation describes the operation of this detector in 2010 and 2011 at the LHC during proton-proton as well as heavy ion collisions. Reconstructed photon conversions and nuclear interactions are used to evaluate the material description of the tracker. The resolution and efficiency of the track and vertex reconstruction are measured with data and compared to the results from simulation. Finally, an outlook is given to the considerations towards an upgrade of the CMS silicon strip tracker for the operation at the high luminosity upgrade of the LHC. Beside the challenges to develop sensors withstanding the high radiation field, CMS is exploring options and developing solutions that would allow to include tracking information into the Level-1 trigger of CMS.

  18. Bonding of the Inner Tracker Silicon Microstrip Modules

    CERN Document Server

    Bosi, Filippo; Brianzi, Mirko; Cariola, P; Costa, Salvatore; Demaria, Natale; Dumitrache, Floarea; Farano, R; Fiore, Luigi; Galet, G; Giudice, Nunzio; Kaminski, A; Mammini, Paolo; Manolescu, Florentina; Pantano, Devis; Profeti, Alessandro; Raimondo, F S; Saizu, Mirela Angela; Scarlini, Enrico; Tempesta, Paolo; Tessaro, Mario

    2008-01-01

    Microbonding of the CMS Tracker Inner Barrel (TIB) and Tracker Inner Disks (TID) modules was shared among six different Italian Institutes. The organization devised and the infrastructure deployed to handle this task is illustrated. Microbonding specifications and procedures for the different types of TIB and TID modules are given. The tooling specially designed and developed for these types of modules is described. Experience of production is presented. Attained production rates are given. An analysis of the microbonding quality achieved is presented, based on bond strengths measured in sample bond pull tests as well as on rates of bonding failures. Italian Bonding Centers routinely performed well above minimum specifications and a very low global introduced failure rate, at the strip level, of only $\\sim$0.015 \\% is observed.

  19. Using Tracker as a pedagogical tool for understanding projectile motion

    Science.gov (United States)

    Wee, Loo Kang; Chew, Charles; Hwee Goh, Giam; Tan, Samuel; Lee, Tat Leong

    2012-07-01

    This article reports on the use of Tracker as a pedagogical tool in the effective learning and teaching of projectile motion in physics. When a computer model building learning process is supported and driven by video analysis data, this free Open Source Physics tool can provide opportunities for students to engage in active enquiry-based learning. We discuss the pedagogical use of Tracker to address some common misconceptions concerning projectile motion by allowing students to test their hypothesis by juxtaposing their mental models against the analysis of real-life videos. Initial research findings suggest that allowing learners to relate abstract physics concepts to real life through coupling computer modelling with traditional video analysis could be an innovative and effective way to learn projectile motion.

  20. LHCb: Installation and operation of the LHCb Silicon Tracker detector

    CERN Multimedia

    Esperante Pereira, D

    2009-01-01

    The LHCb experiment has been designed to perform high-precision measurements of CP violation and rare decays of B hadrons. The construction and installation phases of the Silicon Tracker (ST) of the experiment were completed by early summer 2008. The LHCb Silicon Tracker sums up to a total sensitive area of about 12 m^2 using silicon micro-strip technology and withstands charged particle fluxes of up to 5 x 10^5cm^−2s^−1. We will report on the preparation of the detectors for the first LHC beams. Selected results from the commissioning in LHCb are shown, including the first beam-related events accumulated during LHC injection tests in September 2008. Lessons are drawn from the experience gathered during the installation and commissioning.

  1. Tracker: Image-Processing and Object-Tracking System Developed

    Science.gov (United States)

    Klimek, Robert B.; Wright, Theodore W.

    1999-01-01

    Tracker is an object-tracking and image-processing program designed and developed at the NASA Lewis Research Center to help with the analysis of images generated by microgravity combustion and fluid physics experiments. Experiments are often recorded on film or videotape for analysis later. Tracker automates the process of examining each frame of the recorded experiment, performing image-processing operations to bring out the desired detail, and recording the positions of the objects of interest. It can load sequences of images from disk files or acquire images (via a frame grabber) from film transports, videotape, laser disks, or a live camera. Tracker controls the image source to automatically advance to the next frame. It can employ a large array of image-processing operations to enhance the detail of the acquired images and can analyze an arbitrarily large number of objects simultaneously. Several different tracking algorithms are available, including conventional threshold and correlation-based techniques, and more esoteric procedures such as "snake" tracking and automated recognition of character data in the image. The Tracker software was written to be operated by researchers, thus every attempt was made to make the software as user friendly and self-explanatory as possible. Tracker is used by most of the microgravity combustion and fluid physics experiments performed by Lewis, and by visiting researchers. This includes experiments performed on the space shuttles, Mir, sounding rockets, zero-g research airplanes, drop towers, and ground-based laboratories. This software automates the analysis of the flame or liquid s physical parameters such as position, velocity, acceleration, size, shape, intensity characteristics, color, and centroid, as well as a number of other measurements. It can perform these operations on multiple objects simultaneously. Another key feature of Tracker is that it performs optical character recognition (OCR). This feature is useful in

  2. The reconstruction software for the MICE scintillating fibre trackers

    CERN Document Server

    Dobbs, A; Long, K; Santos, E; Uchida, M A; Kyberd, P; Heidt, C; Blot, S; Overton, E

    2016-01-01

    The Muon Ionization Cooling Experiment (MICE) will demonstrate the principle of muon beam phase-space reduction via ionization cooling. Muon beam cooling will be required for the proposed Neutrino Factory or Muon Collider. The phase-space before and after the cooling cell must be measured precisely. This is achieved using two scintillating-fibre trackers, each placed in a solenoidal magnetic field. This paper describes the software reconstruction for the fibre trackers: the GEANT4 based simulation; the implementation of the geometry; digitisation; space-point reconstruction; pattern recognition; and the final track fit based on a Kalman filter. The performance of the software is evaluated by means of Monte Carlo studies and the precision of the final track reconstruction is evaluated.

  3. Radiation Hard Sensor Materials for the CMS Tracker Upgrade

    CERN Document Server

    Bergholz, Matthias

    2011-01-01

    The upgrade of the LHC machine to deliver a significantly higher luminosity of about 5x10$^{34}$ cm$^{-2}$s$^{-1}$ is planned to be operational after 2020. This will significantly increase the radiation dose of the inner detector systems, requiring new radiation hard sensor materials for the CMS Tracker. To identify the appropriate materials, which are able to withstand the radiation environment in the middle to outer layers of the CMS Tracker during the full lifetime of the high luminosity LHC, a large irradiation and measurement campaign has been started. Several test structures and sensors have been designed and manufactured on 18 different combinations of wafer materials, thicknesses and production technologies. The structures will be electrically characterized before and after irradiation with different doses of neutrons and protons.

  4. Measurement uncertainty analysis on laser tracker combined with articulated CMM

    Science.gov (United States)

    Zhao, Hui-ning; Yu, Lian-dong; Du, Yun; Zhang, Hai-yan

    2013-10-01

    The combined measurement technology plays an increasingly important role in the digitalized assembly. This paper introduces a combined measurement system consists of a Laser tracker and a FACMM,with the applications in the inspection of the position of the inner parts in a large-scale device. When these measurement instruments are combined, the resulting coordinate data set contains uncertainties that are a function of the base data sets and complex interactions between the measurement sets. Combined with the characteristics of Laser Tracker and Flexible Articulated Coordinate Measuring Machine (FACMM),Monte-Claro simulation mothed is employed in the uncertainty evaluation of combined measurement systems. A case study is given to demonstrate the practical applications of this research.

  5. A Novel Solar Tracker Based on Omnidirectional Computer Vision

    OpenAIRE

    Zakaria El Kadmiri; Omar El Kadmiri; Lhoussaine Masmoudi; Mohammed Najib Bargach

    2015-01-01

    This paper presents a novel solar tracker system based on omnidirectional vision technology. The analysis of acquired images with a catadioptric camera allows extracting accurate information about the sun position toward both elevation and azimuth. The main advantages of this system are its wide field of tracking of 360° horizontally and 200° vertically. The system has the ability to track the sun in real time independently of the spatiotemporal coordinates of the site. The extracted informat...

  6. A prototype for the LHCb silicon tracker data readout system

    CERN Document Server

    Vollhardt, A

    2003-01-01

    This note reports the development of the digital optical readout system for the LHCb Silicon Tracker. We describe the migration from the first functional prototype to a full prototype with all of the used components planned for use in the final detector system. We also present cable studies done for the analogue copper transmission line needed between the front-end amplifiers and the digitizing stage. Price estimates for full production quantities are given.

  7. ATLAS Inner Detector (Pixel Detector and Silicon Tracker)

    CERN Multimedia

    ATLAS Outreach

    2006-01-01

    To raise awareness of the basic functions of the Pixel Detector and Silicon Tracker in the ATLAS detector on the LHC at CERN. This colorful 3D animation is an excerpt from the film "ATLAS-Episode II, The Particles Strike Back." Shot with a bug's eye view of the inside of the detector. The viewer is taken on a tour of the inner workings of the detector, seeing critical pieces of the detector and hearing short explanations of how each works.

  8. Development of the inner tracker detector electronics for LHCb

    CERN Document Server

    Vollhardt, A

    2002-01-01

    This paper describes the development and testing of the Inner Tracker detector modules including the silicon sensors and the electronic readout hybrid with the Beetle frontend chip. Testbeam measurements on the sensor performance including signal-to-noise and efficiency are discussed. We also present preformance studies on the digital optical transmission line. Talk presented at 8th workshop on Electronics for LHCb Experiments, Colmar, September 9-13, 2002

  9. A new silicon tracker for proton imaging and dosimetry

    Science.gov (United States)

    Taylor, J. T.; Waltham, C.; Price, T.; Allinson, N. M.; Allport, P. P.; Casse, G. L.; Kacperek, A.; Manger, S.; Smith, N. A.; Tsurin, I.

    2016-09-01

    For many years, silicon micro-strip detectors have been successfully used as tracking detectors for particle and nuclear physics experiments. A new application of this technology is to the field of particle therapy where radiotherapy is carried out by use of charged particles such as protons or carbon ions. Such a treatment has been shown to have advantages over standard x-ray radiotherapy and as a result of this, many new centres offering particle therapy are currently under construction around the world today. The Proton Radiotherapy, Verification and Dosimetry Applications (PRaVDA) consortium are developing instrumentation for particle therapy based upon technology from high-energy physics. The characteristics of a new silicon micro-strip tracker for particle therapy will be presented. The array uses specifically designed, large area sensors with technology choices that follow closely those taken for the ATLAS experiment at the HL-LHC. These detectors will be arranged into four units each with three layers in an x-u-v configuration to be suitable for fast proton tracking with minimal ambiguities. The sensors will form a tracker capable of tracing the path of ~200 MeV protons entering and exiting a patient allowing a new mode of imaging known as proton computed tomography (pCT). This will aid the accurate delivery of treatment doses and in addition, the tracker will also be used to monitor the beam profile and total dose delivered during the high fluences used for treatment. We present here details of the design, construction and assembly of one of the four units that will make up the complete tracker along with its characterisation using radiation tests carried out using a 90Sr source in the laboratory and a 60 MeV proton beam at the Clatterbridge Cancer Centre.

  10. Resonance interaction in LBNE fine-grained-tracker near detector

    Energy Technology Data Exchange (ETDEWEB)

    Duyang, Hongyue; Tian, Xinchun; Mishra, Sanjib R. [Department of Physics and Astronomy, University of South Carolina, 712 Main St, Columbia, SC 29208 (United States)

    2015-10-15

    This talk is devoted to resonance interaction (RES) in the proposed fine-grained tracker detector (FGT) for LBNE experiment. We use fast MC to study the sensitivity of FGT to RES, and use this measurement as a handle to constrain nuclear effects. Similar analysis is performed on NOMAD data for validation and better understanding. Preliminary RES measurement result using NOMAD data will be reported.

  11. Resonance interaction in LBNE fine-grained-tracker near detector

    Science.gov (United States)

    Duyang, Hongyue; Tian, Xinchun; Mishra, Sanjib R.

    2015-10-01

    This talk is devoted to resonance interaction (RES) in the proposed fine-grained tracker detector (FGT) for LBNE experiment. We use fast MC to study the sensitivity of FGT to RES, and use this measurement as a handle to constrain nuclear effects. Similar analysis is performed on NOMAD data for validation and better understanding. Preliminary RES measurement result using NOMAD data will be reported.

  12. LHCb Silicon Tracker DAQ and DCS Online Systems

    CERN Multimedia

    Buechler, A; Rodriguez, P

    2009-01-01

    The LHCb experiment at the Large Hadron Collider (LHC) at CERN in Geneva Switzerland is specialized on precision measurements of b quark decays. The Silicon Tracker (ST) contributes a crucial part in tracking the particle trajectories and consists of two silicon micro-strip detectors, the Tracker Turicensis upstream of the LHCb magnet and the Inner Tracker downstream. The radiation and the magnetic field represent new challenges for the implementation of a Detector Control System (DCS) and the data acquisition (DAQ). The DAQ has to deal with more than 270K analog readout channels, 2K readout chips and real time DAQ at a rate of 1.1 MHz with data processing at TELL1 level. The TELL1 real time algorithms for clustering thresholds and other computations run on dedicated FPGAs that implement 13K configurable parameters per board, in total 1.17 K parameters for the ST. After data processing the total throughput amounts to about 6.4 Gbytes from an input data rate of around ~337 Gbytes per second. A finite state ma...

  13. i-Tracker: For quantitative proteomics using iTRAQ™

    Directory of Open Access Journals (Sweden)

    Lilley Kathryn S

    2005-10-01

    Full Text Available Abstract Background iTRAQ™ technology for protein quantitation using mass spectrometry is a recent, powerful means of determining relative protein levels in up to four samples simultaneously. Although protein identification of samples generated using iTRAQ may be carried out using any current identification software, the quantitation calculations have been restricted to the ProQuant software supplied by Applied Biosciences. i-Tracker software has been developed to extract reporter ion peak ratios from non-centroided tandem MS peak lists in a format easily linked to the results of protein identification tools such as Mascot and Sequest. Such functionality is currently not provided by ProQuant, which is restricted to matching quantitative information to the peptide identifications from Applied Biosciences' Interrogator™ software. Results i-Tracker is shown to generate results that are consistent with those produced by ProQuant, thus validating both systems. Conclusion i-Tracker allows quantitative information gained using the iTRAQ protocol to be linked with peptide identifications from popular tandem MS identification tools and hence is both a timely and useful tool for the proteomics community.

  14. Nemesis Autonomous Test System

    Science.gov (United States)

    Barltrop, Kevin J.; Lee, Cin-Young; Horvath, Gregory A,; Clement, Bradley J.

    2012-01-01

    A generalized framework has been developed for systems validation that can be applied to both traditional and autonomous systems. The framework consists of an automated test case generation and execution system called Nemesis that rapidly and thoroughly identifies flaws or vulnerabilities within a system. By applying genetic optimization and goal-seeking algorithms on the test equipment side, a "war game" is conducted between a system and its complementary nemesis. The end result of the war games is a collection of scenarios that reveals any undesirable behaviors of the system under test. The software provides a reusable framework to evolve test scenarios using genetic algorithms using an operation model of the system under test. It can automatically generate and execute test cases that reveal flaws in behaviorally complex systems. Genetic algorithms focus the exploration of tests on the set of test cases that most effectively reveals the flaws and vulnerabilities of the system under test. It leverages advances in state- and model-based engineering, which are essential in defining the behavior of autonomous systems. It also uses goal networks to describe test scenarios.

  15. Towards autonomous vehicular clouds

    Directory of Open Access Journals (Sweden)

    Stephan Olariu

    2011-09-01

    Full Text Available The dawn of the 21st century has seen a growing interest in vehicular networking and its myriad potential applications. The initial view of practitioners and researchers was that radio-equipped vehicles could keep the drivers informed about potential safety risks and increase their awareness of road conditions. The view then expanded to include access to the Internet and associated services. This position paper proposes and promotes a novel and more comprehensive vision namely, that advances in vehicular networks, embedded devices and cloud computing will enable the formation of autonomous clouds of vehicular computing, communication, sensing, power and physical resources. Hence, we coin the term, autonomous vehicular clouds (AVCs. A key feature distinguishing AVCs from conventional cloud computing is that mobile AVC resources can be pooled dynamically to serve authorized users and to enable autonomy in real-time service sharing and management on terrestrial, aerial, or aquatic pathways or theaters of operations. In addition to general-purpose AVCs, we also envision the emergence of specialized AVCs such as mobile analytics laboratories. Furthermore, we envision that the integration of AVCs with ubiquitous smart infrastructures including intelligent transportation systems, smart cities and smart electric power grids will have an enormous societal impact enabling ubiquitous utility cyber-physical services at the right place, right time and with right-sized resources.

  16. Learning for Autonomous Navigation

    Science.gov (United States)

    Angelova, Anelia; Howard, Andrew; Matthies, Larry; Tang, Benyang; Turmon, Michael; Mjolsness, Eric

    2005-01-01

    Robotic ground vehicles for outdoor applications have achieved some remarkable successes, notably in autonomous highway following (Dickmanns, 1987), planetary exploration (1), and off-road navigation on Earth (1). Nevertheless, major challenges remain to enable reliable, high-speed, autonomous navigation in a wide variety of complex, off-road terrain. 3-D perception of terrain geometry with imaging range sensors is the mainstay of off-road driving systems. However, the stopping distance at high speed exceeds the effective lookahead distance of existing range sensors. Prospects for extending the range of 3-D sensors is strongly limited by sensor physics, eye safety of lasers, and related issues. Range sensor limitations also allow vehicles to enter large cul-de-sacs even at low speed, leading to long detours. Moreover, sensing only terrain geometry fails to reveal mechanical properties of terrain that are critical to assessing its traversability, such as potential for slippage, sinkage, and the degree of compliance of potential obstacles. Rovers in the Mars Exploration Rover (MER) mission have got stuck in sand dunes and experienced significant downhill slippage in the vicinity of large rock hazards. Earth-based off-road robots today have very limited ability to discriminate traversable vegetation from non-traversable vegetation or rough ground. It is impossible today to preprogram a system with knowledge of these properties for all types of terrain and weather conditions that might be encountered.

  17. On-the Fly Merging of Attitude Solutions

    DEFF Research Database (Denmark)

    Jørgensen, Peter Siegbjørn; Jørgensen, John Leif; Denver, Troelz

    2008-01-01

    Recent advances in autonomous attitude determination instrumentation enable even small satellites flying fully autonomous multi head star trackers providing full accurate and robust attitude information. Each sensor provides the full attitude information but for robustness and optimal usage...

  18. Expanded Perspectives on Autonomous Learners

    Science.gov (United States)

    Oxford, Rebecca L.

    2015-01-01

    This paper explores two general perspectives on autonomous learners: psychological and sociocultural. These perspectives introduce a range of theoretically grounded facets of autonomous learners, facets such as the self-regulated learner, the emotionally intelligent learner, the self-determined learner, the mediated learner, the socioculturally…

  19. Shooting stars

    Energy Technology Data Exchange (ETDEWEB)

    Maurette, M.; Hammer, C.

    A shooting star passage -even a star shower- can be sometimes easily seen during moonless black night. They represent the partial volatilization in earth atmosphere of meteorites or micrometeorites reduced in cosmic dusts. Everywhere on earth, these star dusts are searched to be gathered. This research made one year ago on the Greenland ice-cap is the object of this article; orbit gathering projects are also presented.

  20. Evolutionary Autonomous Health Monitoring System (EAHMS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — For supporting NASA's Robotics, Tele-Robotics and Autonomous Systems Roadmap, we are proposing the "Evolutionary Autonomous Health Monitoring System" (EAHMS) for...