Статті в журналах: "Guide star"

1

WADA, Satoshi, and Norihito SAITO. "Laser Guide Star." Review of Laser Engineering 39, no. 1 (2011): 30–33. http://dx.doi.org/10.2184/lsj.39.30.

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2

Thompson, Laird A., Scott W. Teare, Yao-Heng Xiong, Richard M. Castle, Abhijit Chakraborty, Robert A. Gruendl, and Robert W. Leach. "UnISIS: Laser Guide Star and Natural Guide Star Adaptive Optics System." Publications of the Astronomical Society of the Pacific 121, no. 879 (May 2009): 498–511. http://dx.doi.org/10.1086/599574.

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3

Wu, Feng, Xifang Zhu, Ruxi Xiang, Qiuyang Yu, Tingting Huang, Qingquan Xu, and Hui Li. "Novel guide star optimal selection algorithm for star sensors based on star clustering." Modern Physics Letters B 32, no. 34n36 (December 30, 2018): 1840089. http://dx.doi.org/10.1142/s0217984918400894.

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Modern space vehicles face the challenges to obtain more and more accurate attitudes in order to complete the demanding tasks. Onboard star sensors which identify the observed stars in the field of view according to the loaded guide star catalog and output accurate attitude have attracted most interests. Guide stars are usually required to distribute uniformly on the celestial sphere to improve the performance of the star pattern identification. An optimal selection algorithm is proposed to achieve an even distribution of guide stars in this paper. Constellation features are discussed. The mean shift algorithm is analyzed. The idea that distributes stars in the local field of view to constellations is proposed by using the star pair angular separations according to the star positions in the inertial coordinate system. The optimal selection algorithm of guide stars based on star clustering is developed. Its detailed implement procedures are introduced completely. The guide star optimal selection experiment in visible band by using SAO star catalog as the original star data is implemented. It proves that the proposed algorithm has the virtue of simple calculation and easy realization. The obtained guide star distribution is superior to the regression selection algorithm and the magnitude weighted method.

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4

Wu, Feng, Xifang Zhu, Qingquan Xu, Ruxi Xiang, Qiuyang Yu, Jie Zhou, and Xiu Yang. "Optimization of guide star catalog for daytime star sensors." International Journal of Modern Physics B 34, no. 01n03 (December 26, 2019): 2040065. http://dx.doi.org/10.1142/s0217979220400652.

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Daytime star sensor provides accuracy navigation information to air vehicles near the ground in the daytime by observing stars. It has been an important development of modern star sensors. In order to achieve a high signal-to-noise ratio, daytime star sensors work in the infrared band to avoid interferences from sky background. Daytime star sensors output accurate attitudes by identifying the observed stars in the field of view (FOV) according to the loaded guide star catalog. Guide stars are usually required to be distributed uniformly on the celestial sphere to improve the performance of star pattern identification. The parameters including limiting magnitude and FOV are determined by processing the 2MASS star catalog as the original star data and performing star distribution statistics. After constellation features are discussed, the idea of distributing stars in the local FOV to constellations is put forward by using the star pair angular separations. An optimization algorithm to build the guide star catalog for daytime stars is proposed to achieve evenly distributed guide stars. The guide star catalog is established and analyzed, proving that the proposed algorithm has simple calculation and easy realization. The Boltzmann entropy of obtained guide star catalog drops two orders of magnitude. Guide stars are distributed more uniformly.

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5

Li, Jian, Gangyi Wang, and Xinguo Wei. "Generation of Guide Star Catalog for Star Trackers." IEEE Sensors Journal 18, no. 11 (June 1, 2018): 4592–601. http://dx.doi.org/10.1109/jsen.2018.2825355.

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6

Russell, Jane L. "The Guide Star Selection System and the Guide Star Catalog for Space Telescope." Symposium - International Astronomical Union 109 (1986): 721–27. http://dx.doi.org/10.1017/s007418090007724x.

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The Guide Star Selection System (GSSS) will provide relative positions of two guide stars and the target for each observation of the Space Telescope as well as photometry for the guide stars. Being developed at the Space Telescope Science Institute, the GSSS is a production system which is based on PDS measurements of Schmidt survey plates. The specified accuracy for the system is +/−0.33 arcsec for the separation of the guide stars and 0.4 mag in the bandpass of the Space Telescope's Fine Guidance Sensors. The GSSS will produce two catalogs which will be used in the operation of the system. The Guide Star Photometry catalog includes photoelectric measurements (+/−0.05 mag) in B and V for six stars over the guide star range, 9.0 to 14.5 visual magnitude, near the central part of each 6 by 6 deg survey plate. The Guide Star Catalog will include the list of all possible guide stars and brighter, positions (at least +/−1 arcsec) and magnitudes (at least +/−0.4 mag) for essentially the whole sky complete to visual magnitude 15.

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7

Wu, Liang, Qian Xu, Haojing Wang, Hongwu Lyu, and Kaipeng Li. "Guide Star Selection for the Three-FOV Daytime Star Sensor." Sensors 19, no. 6 (March 25, 2019): 1457. http://dx.doi.org/10.3390/s19061457.

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To realize the application of the star sensor in the all-day carrier platform, a three-field-of-view (three-FOV) star sensor in short-wave infrared (SWIR) band is considered. This new prototype employs new techniques that can improve the detection capability of the star sensor, when the huge size of star identification feature database becomes a big obstacle. Hence, a way to thin the guide star catalog for three-FOV daytime star sensor is studied. Firstly, an introduction of three-FOV star sensor and an example of three-FOV daytime star sensor with narrow FOV are presented. According to this model and the requirement of triangular star identification method, two constraints based on the number and the brightness of the stars in FOV are put forward for guide star selection. Then on the basis of these constraints, the improved spherical spiral method (ISSM) is proposed and the optimal number of reference points of ISSM is discussed. Finally, to demonstrate the performance of the ISSM, guide star catalogs are generated by ISSM, magnitude filter method (MFM), 1st order self-organizing guide star selection method (1st-SOPM) and the spherical spiral method (SSM), respectively. The results show that the guide star catalog generated by ISSM has the smallest size and the number and brightness characteristics of its guide stars are better than the other methods. ISSM is effective for the guide star selection in the three-FOV daytime star sensor.

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8

Yang, Xuezong, Ondrej Kitzler, David J. Spence, Zhenxu Bai, Yan Feng, and Richard P. Mildren. "Diamond sodium guide star laser." Optics Letters 45, no. 7 (March 20, 2020): 1898. http://dx.doi.org/10.1364/ol.387879.

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9

Lasker, Barry M., Conrad R. Sturch, Carlos Lopez, Anthony D. Mallamas, Steven F. McLaughlin, Jane L. Russell, Wieslaw Z. Wisniewski, et al. "The Guide Star Photometric Catalog." Astrophysical Journal Supplement Series 68 (September 1988): 1. http://dx.doi.org/10.1086/191282.

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10

McLean, B., G. Hawkins, A. Spagna, M. Lattanzi, B. Lasker, H. Jenkner, and R. White. "The Second Guide Star Catalogue." Symposium - International Astronomical Union 179 (1998): 431–32. http://dx.doi.org/10.1017/s0074180900129225.

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Although the HST GSC–I (Paper-I: Lasker et al. 1990, Paper-II: Russell et al. 1990, Paper-III: Jenkner et al. 1990) has been used with great success operationally, it was always known that it was possible to improve the scientific and operational usefulness by an increase in scope to include multi-color and multi-epoch data. Once the GSC-II concept was established, it was evident that, even beyond the original motivations in HST operations, it would address a number of other astronomical needs such as increasing demands for fainter catalogues to support remote or queue scheduling capabilities and adaptive optics on the next generation of large-aperture, new-technology telescopes. In addition, the all sky nature of the GSC–II makes it a natural data source for research in galactic structure.

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11

Norwood, Rick. "A Star to Guide Us." Mathematics Teacher 92, no. 2 (February 1999): 100–101. http://dx.doi.org/10.5951/mt.92.2.0100.

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12

Hartquist, T. W. "Star formation: a beginner's guide." Astronomy & Geophysics 52, no. 5 (September 29, 2011): 5.37. http://dx.doi.org/10.1111/j.1468-4004.2011.52537.x.

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13

Enderlein, Martin, and Wilhelm G. Kaenders. "Sodium Guide Star (R)Evolution." Optik & Photonik 11, no. 5 (December 2016): 31–35. http://dx.doi.org/10.1002/opph.201600038.

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14

WU Liang, 吴量, 王建立 WANG Jian-li, and 王昊京 WANG Hao-jing. "Guide star selection for star pattern recognition between three FOVs." Optics and Precision Engineering 23, no. 6 (2015): 1732–41. http://dx.doi.org/10.3788/ope.20152306.1732.

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15

Zhang, C., C. Chen, and X. Shen. "Boltzmann entropy-based guide star selection algorithm for star tracker." Electronics Letters 40, no. 2 (2004): 109. http://dx.doi.org/10.1049/el:20040072.

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16

Xu Zuyan, 许祖彦, 薄. 勇. Bo Yong, 彭钦军 Peng Qinjun, 张雨东 Zhang Yudong, 魏. 凯. Wei Kai, 薛随建 Xue Suijian, and 冯. 麓. Feng Lu. "Progress on sodium laser guide star." Infrared and Laser Engineering 45, no. 1 (2016): 0101001. http://dx.doi.org/10.3788/irla201645.0101001.

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17

Xu Zuyan, 许祖彦, 薄. 勇. Bo Yong, 彭钦军 Peng Qinjun, 张雨东 Zhang Yudong, 魏. 凯. Wei Kai, 薛随建 Xue Suijian, and 冯. 麓. Feng Lu. "Progress on sodium laser guide star." Infrared and Laser Engineering 45, no. 1 (2016): 101001. http://dx.doi.org/10.3788/m0001820164501.101001.

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18

Raloff, J. "Star Wars: Lasers Can Guide Electrons." Science News 127, no. 15 (April 13, 1985): 230. http://dx.doi.org/10.2307/3969696.

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19

Nichols, Joy S., Arne A. Henden, David P. Huenemoerder, Jennifer L. Lauer, Eric Martin, Douglas L. Morgan, and Beth A. Sundheim. "THE CHANDRA VARIABLE GUIDE STAR CATALOG." Astrophysical Journal Supplement Series 188, no. 2 (June 1, 2010): 473–87. http://dx.doi.org/10.1088/0067-0049/188/2/473.

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20

Li, Xinlu, Jinhua Yang, Liu Zhang, Shuang Li, and Guang Jin. "A New Simplified Selection Algorithm of the Guide Star Catalogue for a Star Sensor." Journal of Navigation 67, no. 6 (July 15, 2014): 984–94. http://dx.doi.org/10.1017/s0373463314000411.

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A guide star catalogue characterised by fewer guide stars, uniform distribution and high completeness is conducive to the improvement of star pattern identification and star tracking efficiency, and it has become an important study objective. A screening method, which takes “quasi-uniform distribution” of space solid angles as the principle and the size of the space solid angle corresponding to 4°×4° on the equator as the reference and divided the whole celestial sphere into 2,664 sub-blocks in sequence, is proposed in this paper. Based on this method, a “quasi-uniform” guide star catalogue with 2,937 guide stars was obtained. According to our ergodic statistical analysis of the whole celestial sphere, in a 12°×12° field of view, after the space solid angle method was used to divide the celestial sphere, the probability of emergence of three guide stars was 99·9% or above, while the number of guide stars decreased by 12·6% compared to the inscribed cube method. It can be concluded that when the completeness is equal, the space solid angle method is superior to the inscribed cube method in both capacity and distribution uniformity.

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21

Lu Yanhua, 鲁燕华, 黄园芳 Huang Yuanfang, 张雷 Zhang Lei, 张凯 Zhang Kai, 唐淳 Tang Chun, 王卫民 Wang Weimin, and 马毅 Ma Yi. "Research Progress of Sodium Guide Star Lasers." Laser & Optoelectronics Progress 48, no. 7 (2011): 071406. http://dx.doi.org/10.3788/lop48.071406.

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22

&NA;. "A STAR-SPANGLED GUIDE TO PROFESSIONAL MATERIALS." Nursing 18, no. 1 (January 1988): 108–10. http://dx.doi.org/10.1097/00152193-198801000-00026.

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23

Rosack, Jim. "STAR*D Findings May Guide Treatment Recommendations." Psychiatric News 41, no. 2 (January 20, 2006): 1–44. http://dx.doi.org/10.1176/pn.41.2.0001.

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24

Parenti, Ronald R., and Richard J. Sasiela. "Laser-guide-star systems for astronomical applications." Journal of the Optical Society of America A 11, no. 1 (January 1, 1994): 288. http://dx.doi.org/10.1364/josaa.11.000288.

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25

Avicola, K., J. M. Brase, J. R. Morris, H. D. Bissinger, J. M. Duff, H. W. Friedman, D. T. Gavel, et al. "Sodium-layer laser-guide-star experimental results." Journal of the Optical Society of America A 11, no. 2 (February 1, 1994): 825. http://dx.doi.org/10.1364/josaa.11.000825.

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26

Russell, J. L., and D. Egret. "Hipparcos – The Tycho Input Catalogue." Highlights of Astronomy 7 (1986): 713–17. http://dx.doi.org/10.1017/s1539299600007176.

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AbstractThe Tycho Input Catalogue will be used as a finding list to identify the stellar data within the stream of raw data received from the Hipparcos star mappers. It is based on an a priori list of stars, namely the Guide Star Catalogue being created for the Hubble Space Telescope at the Space Telescope Science Institute. The Guide Star Catalogue will contain positions and magnitudes for objects in the sky complete to at least 14 mag, and will contain about 20 million stars. The data for the sky complete to approximately 12.5 mag, extracted from the Guide Star Catalogue, along with some additional data from the SIMBAD data base of about 500 000 stars at the Strasbourg Stellar Data Centre, will form the Tycho Input Catalogue of approximately 2 million objects. As of the 1985 IAU General Assembly nearly 50 per cent of the plates for the Guide Star Catalogue had been measured, and 10 per cent of them were completely processed and catalogued.

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27

Li, Guangxi, Lingyun Wang, Ru Zheng, Xin Yu, Yue Ma, Xiao Liu, and Bo Liu. "Research on Partitioning Algorithm Based on Dynamic Star Simulator Guide Star Catalog." IEEE Access 9 (2021): 54663–70. http://dx.doi.org/10.1109/access.2021.3070408.

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28

Perrin, M. D. "Laser Guide Star Adaptive Optics Imaging Polarimetry of Herbig Ae/Be Stars." Science 303, no. 5662 (February 27, 2004): 1345–48. http://dx.doi.org/10.1126/science.1094602.

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29

Hart, Karen. "My Dad, the Star." Early Years Educator 22, no. 10 (May 2, 2021): S14—S15. http://dx.doi.org/10.12968/eyed.2021.22.10.s14.

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Children will enjoy celebrating their dad or special male person by a creating a a unique ‘Avocado Dad’ or a ‘My Dad, the Star’ card. There is also a guide to making a beauiful ‘Me and My Dad’ bookmark.

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30

Yang, Yuanyu, Dayi Yin, Quan Zhang, and Zhiming Li. "Construction of the Guide Star Catalog for Double Fine Guidance Sensors Based on SSBK Clustering." Sensors 22, no. 13 (July 2, 2022): 4996. http://dx.doi.org/10.3390/s22134996.

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In the Chinese Survey Space Telescope (CSST), the Fine Guidance Sensor (FGS) is required to provide high-precision attitude information of the space telescope. The fine star guide catalog is an essential part of the FGS. It is not only the basis for star identification and attitude determination but also the key to determining the absolute attitude of the space telescope. However, the capacity and uniformity of the fine guide star catalog will affect the performance of the FGS. To build a guide star catalog with uniform distribution of guide stars and catalog capacity that is as small as possible, and to effectively improve the speed of star identification and the accuracy of attitude determination, the spherical spiral binary K-means clustering algorithm (SSBK) is proposed. Based on the selection criteria, firstly, the spherical spiral reference point method is used for global uniform division, and then, the K-means clustering algorithm in machine learning is introduced to divide the stars into several disjoint subsets through the use of angular distance and dichotomy so that the guide stars are uniformly distributed. We assume that the field of view (FOV) is 0.2° × 0.2°, the magnitude range is 9∼15 mag, and the threshold for the number of stars (NOS) in the FOV is 9. The simulation shows that compared with the magnitude filtering method (MFM) and the spherical spiral reference point brightness optimization algorithm (SSRP), the guide star catalog based on the SSBK algorithm has the lowest standard deviation of the NOS in the FOV, and the probability of 5∼15 stars is the highest (over 99.4%), which can ensure a higher identification probability and attitude determination accuracy.

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31

Femenía, Bruno. "Tip–tilt reconstruction with a single dim natural guide star in multiconjugate adaptive optics with laser guide stars." Journal of the Optical Society of America A 22, no. 12 (December 1, 2005): 2719. http://dx.doi.org/10.1364/josaa.22.002719.

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32

Ott, T., R. Davies, and S. Rabien. "Adaptive Optics with a Laser Guide Star - The ALFA system." Symposium - International Astronomical Union 205 (2001): 453–54. http://dx.doi.org/10.1017/s0074180900221748.

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All 8-metre class telescopes will be equipped with adaptive optics systems in order to reach their highest angular resolutions. With the additional requirement for maximal sky coverage comes the mandatory use of a laser guide star. ALFA is an adaptive optics system using a sodium laser guide star, which is installed on the 3.5-m telescope at Calar Alto observatory. It has shown that it is possible to reach Strehl ratios better than 20% in the K-band. In this contribution we describe the design of the system, the observational trade-off necessary to use a laser guide star, and the performance that might be expected.

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33

Wang, Wenjie, Xinguo Wei, Jian Li, and Guangjun Zhang. "Guide star catalog generation for short-wave infrared (SWIR) All-Time star sensor." Review of Scientific Instruments 89, no. 7 (July 2018): 075003. http://dx.doi.org/10.1063/1.5023157.

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34

Olivier, S. S., and C. E. Max. "Laser Guide Star Adaptive Optics: Present and Future." Symposium - International Astronomical Union 158 (1994): 283–92. http://dx.doi.org/10.1017/s0074180900107739.

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Feasibility demonstrations using one to two meter telescopes have confirmed the utility of laser beacons as wavefront references for adaptive optics systems. Laser beacon architectures suitable for the new generation of eight and ten meter telescopes are presently under study. This paper reviews the concept of laser guide star adaptive optics and the progress that has been made by groups around the world in implementing such systems. A description of the laser guide star program at LLNL and some experimental results is also presented.

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35

GARDNER, Chester S. "Na Laser Guide Star Technologies for Adaptive Imaging." Review of Laser Engineering 28, no. 12 (2000): 792–95. http://dx.doi.org/10.2184/lsj.28.792.

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36

Holzlöhner, R., S. M. Rochester, D. Bonaccini Calia, D. Budker, J. M. Higbie, and W. Hackenberg. "Optimization of cw sodium laser guide star efficiency." Astronomy and Astrophysics 510 (February 2010): A20. http://dx.doi.org/10.1051/0004-6361/200913108.

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37

Yang, Xuezong, Lei Zhang, Shuzhen Cui, Tingwei Fan, Jinyan Dong, and Yan Feng. "Sodium guide star laser pulsed at Larmor frequency." Optics Letters 42, no. 21 (October 20, 2017): 4351. http://dx.doi.org/10.1364/ol.42.004351.

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38

Foy, Renaud, Michel Tallon, Isabelle Tallon-Bosc, Eric Thiébaut, Jérôme Vaillant, Françoise-Claude Foy, Daniel Robert, et al. "Photometric observations of a polychromatic laser guide star." Journal of the Optical Society of America A 17, no. 12 (December 1, 2000): 2236. http://dx.doi.org/10.1364/josaa.17.002236.

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39

Ragazzoni, R., and E. Marchetti. "Atmospheric characterization for laser guide star adaptive optics." New Astronomy Reviews 42, no. 6-8 (November 1998): 477–79. http://dx.doi.org/10.1016/s1387-6473(98)00056-6.

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40

Zhang, Ruochong, Fei Gao, Xiaohua Feng, Haoran Jin, Shaohua Zhang, Siyu Liu, Yunqi Luo, Bengang Xing, and Yuanjin Zheng. "“Guide Star” Assisted Noninvasive Photoacoustic Measurement of Glucose." ACS Sensors 3, no. 12 (November 28, 2018): 2550–57. http://dx.doi.org/10.1021/acssensors.8b00905.

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41

Jenkner, Helmut. "The Guide Star Catalog and related sky surveys." Astrophysics and Space Science 217, no. 1-2 (July 1994): 31–34. http://dx.doi.org/10.1007/bf00990019.

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42

Vogt, Frédéric P. A., José Luis Álvarez, Domenico Bonaccini Calia, Wolfgang Hackenberg, Pierre Bourget, Ivan Aranda, Callum Bellhouse, et al. "Raman-scattered laser guide-star photons to monitor the scatter of astronomical telescope mirrors." Astronomy & Astrophysics 618 (October 2018): L7. http://dx.doi.org/10.1051/0004-6361/201834135.

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The first observations of laser guide-star photons that are Raman-scattered by air molecules above the Very Large Telescope (VLT) were reported in June 2017. The initial detection came from the Multi-Unit Spectroscopic Explorer (MUSE) optical integral field spectrograph, following the installation of the 4 Laser Guide Star Facility (4LGSF) on Unit Telescope 4 (UT4) of the VLT. In this Letter, we delve further into the symbiotic relationship between the 4LGSF laser guide-star system, the UT4 telescope, and MUSE by monitoring the spectral contamination of MUSE observations by Raman photons over a 27-month period. This dataset reveals that dust particles deposited on the primary and tertiary mirrors of UT4, which are responsible for a reflectivity loss of ∼8% at 6000 Å, contribute (60 ± 5)% to the laser line fluxes detected by MUSE. The flux of Raman lines, which contaminates scientific observations that are acquired with optical spectrographs, thus provides a new, non-invasive means to monitor the evolving scatter properties of the mirrors of astronomical telescopes that are equipped with laser guide-star systems.

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43

Hutchings, J. B. "CFHT Adaptive Optics Imaging of Active Galaxies." Symposium - International Astronomical Union 186 (1999): 345–47. http://dx.doi.org/10.1017/s007418090011294x.

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The CFHT adaptive optics camera uses a visible light guide signal from a star to operate a bimorph mirror. The system is a unit that is operated by the observer and can be used with CCD or HgCdTe detectors. Pixel sizes are of order 0.04″. The amount of correction varies as the guide star brightness, the angular distance from it, and the natural seeing at the time. With good CFHT conditions, a guide star of 13 mag will give JHK images of FWHM near to the diffraction limit (0.1 to 0.15″) up to 20″ away. Correction is worse in the optical, but images of 0.2″ or better can be obtained in R and I-band. The camera performance is described by Rigaut et al (1998).

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44

Hellemeier, J., M. Enderlein, M. Hager, D. Bonaccini Calia, R. L. Johnson, F. Lison, M. O. Byrd, L. A. Kann, M. Centrone, and P. Hickson. "Laser guide star return-flux gain from frequency chirping." Monthly Notices of the Royal Astronomical Society 511, no. 3 (February 9, 2022): 4660–68. http://dx.doi.org/10.1093/mnras/stac343.

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ABSTRACT Spectral hole burning reduces sodium laser guide star efficiency. Due to photon recoil, atoms that are initially resonant with the single-frequency laser get Doppler shifted out of resonance, which reduces the return flux. Frequency-chirped (also known as frequency-swept) continuous-wave lasers have the potential to mitigate the effect of spectral hole burning and even increase the laser guide star efficiency beyond the theoretical limit of a single-frequency laser. We investigate the return flux of frequency-chirped laser guide stars and its dependence on environmental and chirping parameters. On-sky measurements of a frequency-chirped, single-frequency laser guide star are performed at the Roque de los Muchachos Observatory on La Palma. A fast photon-counting receiver system is employed to resolve the return-flux response during laser frequency sweeps gaining insights into the population dynamics of the sodium layer. At a launched laser power of 16.5 W, we find a maximum gain in return flux of 22 per cent compared to a fixed-frequency laser at a chirping amplitude of the order of 150 MHz and a chirping rate of 0.8 MHz µs−1. Time-resolved measurements during the chirping period confirm our understanding of the population dynamics in the sodium layer. These are the first measurements of return-flux enhancement for laser guide stars excited by a single-frequency-chirped continuous-wave laser. For higher laser powers, the effectiveness of chirping is expected to increase, which could be highly beneficial for telescopes equipped with high-power laser guide star adaptive optics systems.

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45

Russell, J. L., and C. A. Williams. "Testing Schmidt Plates for Astrometric Purposes." Symposium - International Astronomical Union 109 (1986): 259–70. http://dx.doi.org/10.1017/s0074180900076671.

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The Guide Star Selection System for the Space Telescope is being developed to find positions (± 0.25 arcsec) and magnitudes (± 0.4 mag) for guide star pairs for every possible ST target. The data available for the astrometric portion of this task are measurements (±1 μm) of plate surveys from the Palomar and UK schmidt telescopes and positional data from the AGK3 and the SAOC. Astrometric testing to date has concentrated on whole plate reductions in the area of the astrometric standard region in Praesepe. Described here are the test procedures derived to measure the effect of the astrometric accuracy of the guide star positions on ST pointing success. The most critical item in the pointing procedure is that the separations of the guide stars and the target over the ST field of view (28 arcmin diameter) be well-known. Any small zero-point shift or rotation of the field relative to the absolute system is tolerable.

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46

Curyto, Kim, Kyle Page, Karen Benson, Laura Wray, and Michele Karel. "Listening to Clinical Teams: Developing Strategies to Support Sustained STAR-VA Implementation." Innovation in Aging 5, Supplement_1 (December 1, 2021): 536. http://dx.doi.org/10.1093/geroni/igab046.2064.

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Abstract Feedback obtained from program evaluations and interviews with CLC team members who participated in STAR-VA helped to inform the development of sustained implementation strategies guided by the CFIR-ERIC Mapping Tool. A CLC readiness assessment was developed to guide selection of new champions and assess for local team readiness to implement STAR-VA. Virtual training materials were developed along with a champion training checklist to prepare additional champions and support team training. We identified key implementation steps and optional strategies to support sustained implementation, developed a sustained implementation guide, associated sustained implementation checklist, and sustainability toolkit. We are piloting a regional community of practice model, encouraging development of and building on relationship networks to promote use of program tools, collaborative problem-solving, feedback, and a shared vision for implementation. We will discuss the importance of tailored strategies for integrating new practices into usual care.

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47

Röser, S., U. Bastian, and A. V. Kuzmin. "Guide Star Catalog Revisited - The Determination of Proper Motions." International Astronomical Union Colloquium 148 (1995): 218–23. http://dx.doi.org/10.1017/s025292110002193x.

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AbstractWe are compiling a catalogue of positions and proper motions of 4 million stars, based on the Guide Star Catalogue (GSC) and the Astrographic Catalogue (AC). The GSC is re-reduced by a method described in this paper. The AC has been newly reduced recently by us for the determination of positions and proper motions of the PPM catalogue.The expected accuracy of the proper motions of the GSC-AC catalogue ranges between 5 and 6 mas/year. Having an average star density of 100 per square degree, this catalogue will be a useful tool for the reduction of CCD frames.

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48

Valtier, J. C., J. M. Le Contel, P. Antonelli, P. Michel, and J. P. Sareyan. "A Four Star Photometer." International Astronomical Union Colloquium 136 (1993): 179–86. http://dx.doi.org/10.1017/s0252921100007545.

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AbstractA new photometer is presently being developed at the O.C.A. Observatory. It consists of four arms and a CCD camera situated in the focal plane of the telescope. Each arm can move in both directions and support a diaphragm and a liquid optic guide that directs the light to a photomultiplier. The simultaneous acquisition of the four signals enables to obtain magnitude differences between the objects in real time. A typical use of this photometer is to observe at the same time one or two variables, comparison stars and the sky background.

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49

Crifo, F., M. Grenon, H. Jahreiß, and B. McLean. "Search of the latest non-astrometric Hipparcos stars in the HST guide-star catalogue." Advances in Space Research 11, no. 2 (January 1991): 137–40. http://dx.doi.org/10.1016/0273-1177(91)90483-z.

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50

Lasker, Barry M., Helmut Jenkner, and Jane L. Russell. "The Guide Star Catalog. I. Overview, History, And Prospective." Symposium - International Astronomical Union 133 (1988): 229–33. http://dx.doi.org/10.1017/s0074180900139634.

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