Journal articles: 'Telescopic cover'

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Khanna, Rohit, and Lisa Ferrara. "Dynamic telescopic craniotomy: a cadaveric study of a novel device and technique." Journal of Neurosurgery 125, no. 3 (September 2016): 674–82. http://dx.doi.org/10.3171/2015.6.jns15706.

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OBJECT The authors assessed the feasibility of the dynamic decompressive craniotomy technique using a novel cranial fixation plate with a telescopic component. Following a craniotomy in human cadaver skulls, the telescopic plates were placed to cover the bur holes. The plates allow constrained outward movement of the bone flap upon an increase in intracranial pressure (ICP) and also prevent the bone flap from sinking once the ICP normalizes. The authors compared the extent of postcraniotomy ICP control after an abrupt increase in intracranial volume using the dynamic craniotomy technique versus the standard craniotomy or hinge craniotomy techniques. METHODS Fixation of the bone flap after craniotomy was performed in 5 cadaver skulls using 3 techniques: 1) dynamic telescopic craniotomy, 2) hinge craniotomy, and 3) standard craniotomy with fixed plates. The ability of each technique to allow for expansion during intracranial hypertension was evaluated by progressively increasing intracranial volume. Biomechanical evaluation of the telescopic plates with load-bearing tests was also undertaken. RESULTS Both the dynamic craniotomy and the hinge craniotomy techniques provided significant control of ICP during increases in intracranial volume as compared with the standard craniotomy technique. With the standard craniotomy, ICP increased from a mean of 11.4 to 100.1 mm Hg with the addition of 120 ml of intracranial volume. However, with the dynamic craniotomy, the addition of 120 ml of intracranial volume increased the ICP from a mean of 2.8 to 13.4 mm Hg, maintaining ICP within the normal range as compared with the standard craniotomy (p = 0.04). The dynamic craniotomy was also superior in controlling ICP as compared with the hinge craniotomy, providing expansion for an additional 40 ml of intracranial volume while maintaining ICP within a normal range (p = 0.008). Biomechanical load-bearing tests for the dynamic telescopic plates revealed rigid restriction of bone-flap sinking as compared with standard fixation plates and clamps. CONCLUSIONS The dynamic telescopic craniotomy technique with the novel cranial fixation plate provides superior control of ICP after an abrupt increase in intracranial volume as compared with the standard craniotomy and hinge craniotomy techniques.

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Amenábar, Jesús M. "Editorial acerca de “Fístula pancreática posduodenopancreatectomía. Pancreatogastrostomía vs. pancreatoyeyunostomía”." Revista Argentina de Cirugía 111, no. 2 (June 1, 2019): 57–60. http://dx.doi.org/10.25132/raac.v111.n2.edame.esin.

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Pancreatic fistula is the most dreaded complication after pancreaticoduodenectomy due to its morbidity and mortality. Multiple procedures to reduce the incidence of this complication have been described: a- Systematic inhibition of pancreatic enzyme secretion using octapeptide in the postoperative period; bUse of biological fibrin-based adhesive to cover and reinforce the anastomosis; c- Use of omentum flap to wrap the pancreatic anastomosis with the jejunum; dAnastomosis with Wirsung duct stenting; e- Telescopic anastomosis; f- Duct-to-mucosa anastomosis (the most commonly used technique today); g- Use of magnification, etc

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Shukla, Chinmay A., and Amol A. Kulkarni. "Automating multistep flow synthesis: approach and challenges in integrating chemistry, machines and logic." Beilstein Journal of Organic Chemistry 13 (May 19, 2017): 960–87. http://dx.doi.org/10.3762/bjoc.13.97.

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The implementation of automation in the multistep flow synthesis is essential for transforming laboratory-scale chemistry into a reliable industrial process. In this review, we briefly introduce the role of automation based on its application in synthesis viz. auto sampling and inline monitoring, optimization and process control. Subsequently, we have critically reviewed a few multistep flow synthesis and suggested a possible control strategy to be implemented so that it helps to reliably transfer the laboratory-scale synthesis strategy to a pilot scale at its optimum conditions. Due to the vast literature in multistep synthesis, we have classified the literature and have identified the case studies based on few criteria viz. type of reaction, heating methods, processes involving in-line separation units, telescopic synthesis, processes involving in-line quenching and process with the smallest time scale of operation. This classification will cover the broader range in the multistep synthesis literature.

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Li, X., X. Yuan, B. Gu, S. Yang, Z. Li, and F. Du. "CHINESE ANTARCTIC ASTRONOMICAL OPTICAL TELESCOPES." Revista Mexicana de Astronomía y Astrofísica Serie de Conferencias 51 (April 13, 2019): 135–38. http://dx.doi.org/10.22201/ia.14052059p.2019.51.23.

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Due to its superb seeing conditions, the Antarctica plateau is widely considered to be an excellent astronomical site. The long periods of uninterrupted darkness at polar sites such as Dome A provide a possibility of continuous observation for more than three months, which is quite suitable for time-domain astronomy. Since 2008, several wide-field optical photometric telescopes, including Chinese Small Telescope ARray (CSTAR), two of the Three Antarctic Survey Telescopes (AST3), have been deployed on Dome A. Science with these telescopes covers variable stars, supernovas, exoplanets, etc. For the remoteness of the Antarctic plateau, these telescopes are designed to observe autonomously and operate remotely via satellite communication. As for future plan, Kunlun Dark Universe Survey Telescope (KDUST), a 2.5-meter optic/infrared telescope, is being proposed as one of the two major facilities of Chinese Antarctic Observatory.

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Amram, Philippe. "3D Spectroscopic Surveys of Late-Type Nearby Galaxies in the Optical." Proceedings of the International Astronomical Union 6, S277 (December 2010): 89–95. http://dx.doi.org/10.1017/s1743921311022538.

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AbstractTwo classes of spectro-imagers are available, the first one, usually based on grisms, allows to cover intermediate fields of view and wide spectral ranges (decreasing when the spectral resolution increases) while the second one, usually based on tunable filters (like Fabry-Perot), is generally able to cover larger fields of view but on narrow spectral ranges (also depending on the spectral resolution). Both families of instrument have access to low or high spectral resolution and are used in seeing limited conditions for observing nearby galaxies. Spectro-imagers provide data cubes consisting of a spectrum for each spatial sample on the sky. From these spectra, using both emission and absorption lines, combined with the continuum emission, the history of the stars and the interstellar medium in nearby galaxies, encoded in different physical quantities, such as chemical abundances, kinematics properties, is deciphered. Only a few surveys of galaxies using spectro-imagers have been led up to now and mainly using 4-m class or smaller telescopes. This includes the case of nearby late-type galaxies surveyed in the optical. Two large surveys of some 600 galaxies each have just been launched, one on the Magellan 6m telescope (CGS) and the other one on the William Herschel 4.2m telescope (CALIFA). Surveys containing a smaller number of galaxies have been conducted elsewhere, for instance on the WIYN and Calar Alto 3.5m telescopes (the DiskMass survey, 146 galaxies); on the ESO and CFHT 3.6m telescopes (CIGALE, 269 galaxies); on the OHP 1.92m telescope (GHASP, 203 galaxies); on the mont Mégantic 1.6m telescope (107 galaxies) and on the San Pedro Mártir 2.1m telescope (79 galaxies). Other programs surveying less then 50 galaxies have been also led, like VENGA, SAURON, PINGS or GHaFaS. The scientific drivers of these surveys are broad, they span from the study of the structural properties, star formation histories, AGN content, to mass profiles and uncertainties in rotation-curve decompositions, nature and formation of bulges and disks components.

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Cedazo, Raquel, Alberto Brunete, Hugo R. Albarracin, and Esteban Gonzalez. "Open-Design for a Smart Cover of a Night-Time Telescope for Day-Time Use." Sensors 21, no. 4 (February 6, 2021): 1138. http://dx.doi.org/10.3390/s21041138.

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Robotic observatories are ideal infrastructures that can be remotely accessed by scientists, amateurs, and general public for research and education in Astronomy. Its robotization is a complex process for ensuring autonomy, safety, and coordination among all subsystems. Some observatories, such as Francisco Sanchez’s, are equipped with two types of telescopes: one for the night and one for the day. The night-time telescope must be protected from exposure to sunlight in order to use them in an automated way. For this purpose, this article proposes the design and construction of a smart cover that opens and closes according to the time of day. The mechatronic design covers the electronic, mechanical, and software programming, and it has been devised taking while taking the principles of open design, ease of reproduction, low-cost, and smart behaviour into account. The design has been parameterized, so that it can be adapted to telescopes of any size. The final prototype is lightweight, cost-effective, and can be built while using common 3D printing and PCB milling machines. The complete design is licensed under the GNU General Public License v3.0 and all the documentation, schematics, and software are available in public repositories, like Zenodo, GitHub, and Instructables.

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Yang, Guang Pu, Liang Dong, Le Sheng He, Fa Xin Shen, Bin Tian, and Sheng Yang Li. "A New Platform for Radio Astronomy Science Education." Advances in Science and Technology 105 (April 2021): 179–83. http://dx.doi.org/10.4028/www.scientific.net/ast.105.179.

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Radio astronomy telescope can get information from invisible universe by receiving electromagnetic waves. Difference from optical telescopes, there exists many difficulties for making the public understanding the radio astronomy phenomenon. In this paper, we will introduce a new platform for radio astronomy science popularization education in order to help public know radio telescope and radio astronomy. The platform consists of a 0.8meter parabolic antenna, a wide bandwidth low noise amplifier (LNA) and a Software Defined Radio (SDR) terminal. Based on SDR terminal which covers the band from 70MHz to 6GHz, we can get some strong emissions such as the Neutral hydrogen, solar radio bursts and so on in this band. People can carry out many radio astronomy experiments focusing on science popularization by this platform. This new science education tool can interest high school students in science and technology, also students can understand how radio telescopes works.

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Yamagata, Tomohiko, Kimiaki Kawara, Tsutomu Aoki, and Yoshiaki Sofue. "Multicolor Survey For High Redshift Quasars By Kiso Schmidt Telescope." Highlights of Astronomy 11, no. 1 (1998): 482–86. http://dx.doi.org/10.1017/s1539299600021821.

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Several groups have been successful in the survey of high-redshift (z > 4) quasars. For example, Schneider et al. (1994) and Schmidt et al. (1995) were successful in detecting 90 quasars with 2.75 < z < 4.75, R < 21 for 62deg2 using Palomar Transit Grism. Among them, there are 9 quasars with z > 4.0. Storrie-Lombardi et al. (1996) were detected 31 quasars with z > 4.0, mT < 19 for 2500deg2 by APM photographic multicolor survey using UK Schmidt telescope. Survey observations of quasars up to now have to select one of the following conditions; wide field surveys using photographic Schmidt plate which cover large areas but do not go faint enough, or deep surveys using large telescopes which go faint magnitude but which cover relatively small areas.

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CHE, X., L. STURMANN, J. D. MONNIER, T. A. TEN BRUMMELAAR, J. STURMANN, S. T. RIDGWAY, M. J. IRELAND, N. H. TURNER, and H. A. MCALISTER. "OPTICAL AND MECHANICAL DESIGN OF THE CHARA ARRAY ADAPTIVE OPTICS." Journal of Astronomical Instrumentation 02, no. 02 (December 2013): 1340007. http://dx.doi.org/10.1142/s2251171713400072.

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The CHARA array is an optical/near infrared interferometer consisting of six 1-meter diameter telescopes with the longest baseline of 331 m. With high angular resolution, the CHARA array provides a unique and powerful way of studying nearby stellar systems. In 2011, the CHARA array was funded by NSF-ATI for an upgrade of adaptive optics systems to all six telescopes to improve the sensitivity by several magnitudes. The initial grant covers Phase I of the adaptive optics system, which includes an on-telescope Wavefront Sensor and fast tip/tilt correction. We are currently seeking funding for Phase II which will add fast deformable mirrors at the telescopes to close the loop. This paper will describe the design of the project, and show simulations of how much improvement the array will gain after the upgrade.

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Schilbach, E., R. D. Scholz, and S. Hirte. "Wide-Field Stellar Statistics from Tautenburg Schmidt Plates." Symposium - International Astronomical Union 161 (1994): 441–43. http://dx.doi.org/10.1017/s007418090004780x.

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For a detailed investigation of the kinematics of our Galaxy we need accurate proper motions and photometric data of stars over a wide range of magnitudes. The proper motions have to be obtained with respect to an extragalactic, i.e. nonrotating reference system. The best way to determine absolute proper motions of a great number of stars for further statistical analysis is to use the enormous amount of information stored on photographic plates taken with large Schmidt telescopes within the last decades. Since automated measuring machines have become available it is no longer a problem to extract this information from a Schmidt plate. Large Schmidt plates cover a sky area of more than 30 square degrees with usually thousands of stars and hundreds of galaxies per square degree outside the galactic plane. With the Tautenburg Schmidt telescope (134/200/400) more than 8000 plates have been taken in selected Northern sky areas since it was mounted in 1960. A 24 cm × 24 cm Tautenburg plate covers a field of about 10 square degrees, and a 20 minute exposure of a B plate has a limiting magnitude of 19 to 21. In comparison to other large Schmidt telescopes the plate bending is reduced to a minimum due to the four metre focal length and the use of relatively small plates. Therefore irregular positional shifts of the emulsion caused by the rebending after the exposure are of less influence. The large focal length leads to a plate scale of 51 arcsec/mm providing a relatively high positional accuracy.

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Lutz, Julie H. "Distances to Planetary Nebulae." Symposium - International Astronomical Union 131 (1989): 65–72. http://dx.doi.org/10.1017/s0074180900137659.

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Finding distances to planetary nebulae remains a frustrating undertaking, but significant progress has been made over the past several years. This review covers primarily work done on distances since 1980, with some references to earlier papers. Some interesting new methods have been tried recently and some methods that have been used for years have been refined. Missions such as the Hubble Space Telescope and Hipparcos may provide new data on distances. Advances in ground-based telescopes and instruments will make possible new studies of distances.

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Kataza, Hirokazu, Itsuki Sakon, Takehiko Wada, Yuki Sarugaku, Naofumi Fujishiro, Yuji Ikeda, Shinji Mitani, Youichi Ohyama, and Naoto Kobayashi. "Performance Estimation of the Mid-Infrared Camera and Spectrometer Aboard SPICA." Journal of Astronomical Instrumentation 04, no. 01n02 (June 2015): 1550001. http://dx.doi.org/10.1142/s2251171715500014.

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The Space Infrared Telescope for Cosmology and Astrophysics (SPICA) is an astronomical mission optimized for mid- and far-infrared astronomy, envisioned for launch in the 2020s. The Mid-infrared Camera and Spectrometer (MCS) is a model instrument that covers the 5–38[Formula: see text][Formula: see text]m wavelength range and enables imaging and spectroscopic observations via four modules named WFC-S, WFC-L, HRS, and MRS. Both of the wide field camera (WFC) modules have a 5-arcmin square field of view (FOV) but cover different wavelength ranges; WFC for the short wavelength region (WFC-S) covers 5 to 24[Formula: see text][Formula: see text]m, whereas WFC for the long wavelength region (WFC-L) covers 18 to 38[Formula: see text][Formula: see text]m. The High Resolution Spectrometer (HRS) covers the 12–18[Formula: see text][Formula: see text]m range with a resolving power of 22,000–30,000, and the Mid Resolution Spectrometer (MRS) performs integral filed units spectroscopy with a 12[Formula: see text] by 8[Formula: see text] FOV. MRS simultaneously covers the 12–38[Formula: see text][Formula: see text]m range with a moderate resolving power of 720–2000. Here, we report sensitivity estimates from a detailed modeling process involving the instrument itself, the telescope, environmental conditions, and the system error budgets. We show that the WFC-S and HRS modules require an adaptive system to correct for telescope pointing error. In particular, band pass filters (BPFs) longer than 26[Formula: see text][Formula: see text]m should be developed.

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Arranz Martínez, Fernando, Raúl Martín Ferrer, Guillermo Palacios-Navarro, and Pedro Ramos Lorente. "Study on the Vibration Characteristics of the Telescope T80 in the Javalambre Astrophysical Observatory (JAO) Aimed at Detecting Invalid Images." Sensors 20, no. 22 (November 15, 2020): 6523. http://dx.doi.org/10.3390/s20226523.

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The location of large telescopes, generally far from the data processing centers, represents a logistical problem for the supervision of the capture of images. In this work, we carried out a preliminary study of the vibration signature of the T80 telescope at the Javalambre Astrophysical Observatory (JAO). The study analyzed the process of calculating the displacement that occurs because of the vibration in each of the frequencies in the range of interest. We analyzed the problems associated with very low frequencies by means of simulation, finding the most critical vibrations below 20 Hz, since they are the ones that generate greater displacements. The work also relates previous studies based on simulation with the real measurements of the vibration of the telescope taken remotely when it is subjected to different positioning movements (right ascension and/or declination) or when it performs movement actions such as those related to filter trays or mirror cover. The obtained results allow us to design a remote alarm system to detect invalid images (taken with excess vibration).

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Shikhovtsev, A. Yu, L. A. Bolbasova, P. G. Kovadlo, and A. V. Kiselev. "Atmospheric parameters at the 6-m Big Telescope Alt-azimuthal site." Monthly Notices of the Royal Astronomical Society 493, no. 1 (February 19, 2020): 723–29. http://dx.doi.org/10.1093/mnras/staa156.

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ABSTRACT In this paper, we introduce the results of the statistical analysis of atmospheric characteristics at the site of the Big Telescope Alt-azimuthal (BTA) of the Special Astrophysical Observatory (SAO) of the Russian Academy of Science (RAS). The BTA is the largest optical telescope in Eurasia and is located near Mt Pastukhova in the northern part of the Caucasus Mountains, at an altitude of 2070 m above sea level. The atmosphere of the Earth is a major challenge for observing and it limits the quality of astronomical images obtained by ground-based telescopes. The study of the atmosphere above astronomical observatories is important for the planning of observing time, for the optimization of instrument performance and for the development of adaptive optics systems. We discuss the results of a study of the meteorological conditions at the BTA site: total cloud cover, wind speed at the pressure level of 200 hPa, vertical motions, vertical profiles of the wind speed employing data from the ERA-Interim and National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) re-analysis data bases.

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Stobie, R. S., D. Kilkenny, D. O’Donoghue, and A. Chen. "The Edinburgh-Cape Blue Object Survey." International Astronomical Union Colloquium 148 (1995): 280–91. http://dx.doi.org/10.1017/s0252921100022041.

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AbstractThe Edinburgh-Cape Blue Object Survey is a major survey to discover blue stellar objects brighter than B ∼ 18 in the southern sky. It covers an area of sky of 10,000 square degrees with |b| > 30° and δ < 0°. The blue stellar objects are selected by automatic techniques from U and B pairs of UK Schmidt Telescope plates scanned with the COSMOS measuring machine. Follow-up photometry and spectroscopy are being obtained with the SAAO telescopes to classify objects brighter than B = 16.5. This paper describes the survey, the techniques used to extract the blue stellar objects, the photometric accuracy, and the completeness of the survey.

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Phillips, Andre, and Michael C. B. Ashley. "Cloud Imaging from Meteorological Satellites and its Application to Robotic Observing." Publications of the Astronomical Society of Australia 22, no. 4 (2005): 306–10. http://dx.doi.org/10.1071/as05024.

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AbstractSatellite cloud imagery is a standard tool of meteorology, and also of ground-based observational astronomy. Fast access to cloud imagery through the Internet now permits more accurate prediction of local cloud cover than was formerly the case. This is particularly useful for automatic and remotely operated telescopes, where an observer may be at a considerable distance from the telescope itself. Since satellite imagery can now be accessed through the Internet with such ease, direct reception of radio transmissions from weather satellites may seem unnecessary. However, advances in computing power and radio receiver technology permit simple automated receipt of satellite transmissions, particularly from the NOAA series of low Earth orbit satellites. This has the advantage of more up-to-date, and higher resolution, cloud imagery than can be obtained from the Internet. We have operated such a satellite receiving station since 2003 April, and have found it particularly useful when remotely operating our telescopes at Siding Spring Observatory (SSO). By automatically publishing our cloud imagery onto the World Wide Web we have established a resource that is widely used by other local observatories and by the general public.

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Perfetti, L., F. Fassi, and C. Rossi. "FISHEYE PHOTOGRAMMETRY TO GENERATE LOW-COST DTMS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W17 (November 29, 2019): 257–63. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w17-257-2019.

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Abstract. In the archaeological practice, Digital Terrain Models (DTMs) and Digital Surface Models (DSMs) may be used to represent spatial information about the site by conveying information such as differences in levels, morphology of the terrain and movements of volumes during the excavation. Nowadays DTMs and DSMs can be easily obtained by image-based matching using low altitude aerial dataset acquired from a digital camera by means of a lifting device. In recent years, the spread of commercial multi-rotor unmanned aerial vehicles and their decreasing cost made low-altitude aerial photography even easier than before, where balloons, kites and telescopic masts would have been used instead. However, the use of drones is often forbidden by law, especially in the archaeological areas, and therefore a more traditional approach must to be adopted instead.This paper presents two different approaches adopted on the field to acquire the DTM of an archaeological excavation: the use of a pole held by a chest harness to lift a camera up to 3.5 m height fitted with a 20 mm wide angle lens; and a second solution that exploits ground-based fisheye photogrammetry. In general, an image network acquired from ground level is challenging due to: i) the poor coverage that can be obtained on the ground, ii) the large number of images that are required to cover large areas and consequently iii) the longer elaboration time that is required to process the data. The fisheye approach, however, proved to be more effective thanks to the more robust image network resulting both from the wider field of view and from the possibility to handle large datasets by downsampling the images and still retrieving strong key points. The main difference with the first system is that the monotonous images acquired by the 20 mm lens, very plain in texture, require working at full resolution in order to distinguish valid features in the sand.The final product of the tests carried out along this line in 2019 at Saqqara (Egypt) is a comprehensive DSM of the entire archaeological site with an accuracy of ~3 cm.

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Harris, Alan W., Helen J. Walker, and Timothy J. Sumner. "The Potential of the Wide Field Camera on ROSAT for Investigations of the XUV Background." Symposium - International Astronomical Union 139 (1990): 463–64. http://dx.doi.org/10.1017/s0074180900241302.

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The ROSAT X-ray astronomy satellite, due to be launched in early 1990, will carry two separate and complementary grazing-incidence telescopes with co-aligned axes. The German X-ray telescope (XRT) will cover the soft X-ray region in the range 0.15–2 keV (6–80 Å), while the U.K. XUV Wide Field Camera (WFC) will extend coverage to beyond 200 Å. The WFC is a joint project of Leicester and Birmingham Universities, the Mullard Space Science Laboratory, and the authors' institutes. The primary objective of ROSAT is to perform an all-sky survey over a period of six months. This will be followed by a guest-observer, “pointed” phase. We briefly discuss the sensitivity of the WFC to the soft X-ray/XUV background (SXRB) and the problems and techniques associated with distinguishing the astronomical background from other sources of background.

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Richichi, A. "The VLT Interferometer." Proceedings of the International Astronomical Union 3, S248 (October 2007): 44–47. http://dx.doi.org/10.1017/s1743921308018607.

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AbstractThe ESO Very Large Telescope Interferometer (VLTI) is arguably the most powerful optical interferometric facility available at present. In addition to the wide choice of baselines and the light collecting power of its 8.2 m and 1.8 m telescopes, the VLTI also offers a smooth and user-friendly operation which makes interferometry accessible to any astronomer and covers a wide range of scientific applications. Behind the routine scientific operations, however, the VLTI is in constant evolution. I will present some of the technological and instrumental improvements which are planned for the near and mid-term future, and discuss their implications for astrometry in particular. Among them, the PRIMA facility and the proposed GRAVITY instrument are designed to reach the level of 10 microarcseconds in the near-infrared.

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Savage, A., R. D. Cannon, R. S. Stobie, D. Kilkenny, D. O'Donoghue, and An-Le Chen. "Preliminary Results from the Edinburgh-Cape Bright QSO Survey (ECBQS)." Publications of the Astronomical Society of Australia 10, no. 3 (1993): 265–67. http://dx.doi.org/10.1017/s1323358000025820.

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AbstractThe Edinburgh-Cape Bright QSO Survey is a very small sub-set of the Edinburgh Cape Blue Object Survey, which is a major survey to discover blue stellar objects brighter than B~18 in the southern sky. It will cover an area of sky of 10,000 square degrees with |b|>30 and dec <0. The blue stellar objects are selected by automatic techniques from U and B pairs of UK Schmidt Telescope plates scanned with the COSMOS measuring machine. Follow-up photometry and spectroscopy is being obtained with the SAAO telescopes to classify the types of objects brighter than B=16.5, with some of the more stubborn objects being subjected to AAO service spectroscopy. Some preliminary results for the 6% QSO minority are presented in this paper and comparison is made with the Palomar-Green QSO Survey in the north, which we find to be at least a factor of two incomplete.

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Escudero Sanz, Isabel, Astrid Heske, and Jeffrey C. Livas. "A telescope for LISA – the Laser Interferometer Space Antenna." Advanced Optical Technologies 7, no. 6 (December 19, 2018): 395–400. http://dx.doi.org/10.1515/aot-2018-0044.

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Abstract Gravitational waves are a prediction of Einstein’s general relativity theory. In autumn 2017, the Laser Interferometer Gravitational-Wave Observatory (LIGO; https://www.ligo.caltech.edu/) experiment reported the first detection of gravitational waves in addition to electromagnetic radiation from the collision of two neutron stars. This marks the first time that a cosmic event has been viewed in both gravitational waves and light and opens the door to a new type of astronomical observatory based on gravitational waves. The gravitational wave spectrum covers a broad span of frequencies and requires both space- and ground-based observatories to cover the full range. Space-based gravitational wave observatories, such as the proposed Laser Interferometer Space Antenna (LISA), operate at frequencies between 0.1 mHz and 1 Hz and complement the frequency range of 30–1000 Hz accessible by ground-based gravitational wave observatories, such as LIGO. A rich array of high-energy astrophysical sources is expected in the LISA measurement band. LISA was selected in 2017 as the third large mission of the Cosmic Vision program of the European Space Agency. The National Aeronautics and Space Administration will collaborate on both the scientific and technical aspects of this mission. This paper addresses the design of the optical telescope as an essential component of LISA’s long-distance interferometric measurement system.

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Chen, Jian-Sheng. "Schmidt CCD Astronomy at BAO." International Astronomical Union Colloquium 148 (1995): 30–32. http://dx.doi.org/10.1017/s0252921100021631.

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AbstractCurrent users only use CCDs to cover a small fraction of the Schmidt fields. We discuss what kind of Schmidt astronomy is more efficient and the advantages of Schmidt telescopes over reflecting telescopes. The BAO CCD multi-object light curve survey system and the BATC 15 colour survey are introduced.

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Hofmann, Werner. "Perspectives from CTA in relativistic astrophysics." International Journal of Modern Physics D 26, no. 03 (February 3, 2017): 1730005. http://dx.doi.org/10.1142/s0218271817300051.

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The Cherenkov telescope array (CTA) is a next-generation observatory for very high energy (VHE) gamma-ray astronomy. With one array of imaging atmospheric Cherenkov telescopes each in the Northern and Southern Hemispheres, CTA will provide full-sky coverage, enhance flux sensitivity by one order of magnitude compared to current instruments, cover gamma-ray energies from 20 GeV to 300 GeV, and provide a wide field of view with angular resolution of a few arc-minutes. Science themes to be addressed by the CTA observatory include (i) understanding the origin of relativistic cosmic particles, and the role these play in the evolution of star forming systems and galaxies, (ii) probing extreme environments such as neutron stars and black holes, but also the cosmic voids, and (iii) exploring frontiers in physics such as the nature of dark matter. With its superior performance, the prospects for CTA combine guaranteed science — the in-depth understanding of known objects and mechanisms — with anticipated detection of new classes of gamma-ray emitters and new phenomena, and a very significant potential for fundamentally new discoveries.

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Hearnshaw, J. B. "Access to Telescopes in Developing Countries." Highlights of Astronomy 11, no. 2 (1998): 920–22. http://dx.doi.org/10.1017/s153929960001916x.

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The ambiguity in this paper’s title is deliberate. Are we talking about astronomers or telescopes in developing countries? And are the countries concerned developing economically or astronomically? In practice I will cover both options in each case.The list below summarizes six possible routes for the acquisition of astronomical observational data that may be available to astronomers in countries developing economically, astronomically or in both ways. Not all these options will be available in any one case; indeed most of them will probably not be available. However, examples of all of them can readily be found.

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Shlyapnikov, Aleksei, Maksim Gorbunov, Mark Gоrbachev, and Ruslan Akmetdinov. "Archives of CrAO spectral observations. Catalogues of objects and images." Acta Astrophysica Taurica 1, no. 1 (April 15, 2020): 23–29. http://dx.doi.org/10.31059/aat.vol1.iss1.pp23-29.

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The work described in this article is a continuation of the previously initiated research on archival spectral observations carried out in Crimea. It covers a time interval of about 90 years and contains information about spectroscopy using various facilities: from the wide-angle astrographs with an objective prism to the main CrAO telescope - ZTSh. A brief history of telescopes and their equipment is presented. The article is illustrated with possibilities of a network access to the catalogues of observations taken with various instruments in the interactive Aladin Sky Atlas with the redirection to original spectrograms. To this aim, the linear coordinates of scanned negatives were converted into a scale that corresponds to the wavelengths. The possibilities of taking into account the spectral sensitivity of the recorded images by the absolute energy distribution are shown. A feature of this work is the connection of digitized original observations and results of their independent processing with data published for objects in the Izvestiya Krymskoi Astrofizicheskoi Observatorii

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Bouton, Ellen, and Sarah Stevens-Rayburn. "Preprint Databases at NRAO and STScI." International Astronomical Union Colloquium 110 (1989): 113–16. http://dx.doi.org/10.1017/s0252921100003110.

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A couple of different facts coalesced in the mid-70s that forced us to try to come up with a manageable scheme for handling preprints. First, as librarians at the National Radio Astronomy Observatory, we were charged with tracking papers by NRAO staff and by visitors using Nrao telescopes to provide an annual listing of staff and visitor publications and to aid in compiling statistics on telescope use.Second, staff and visitors kept asking for preprints — by series and/or by author, subject, or cover color — and the number of preprint series being received had increased to the point where we could no longer always pull that information off the tops of our heads. So, after consulting with colleagues who had similar concerns, we put together a database in 1978, modestly based on the highly successful Preprint/Antipreprint lists produced by the Stanford Linear Accelerator Center. We decided to produce a biweekly list of new papers received and an as-needed list of recently published papers. The scientific staff were very enthusiastic from the beginning, seeing that our efforts would make their efforts to keep up with the literature that much easier.

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Jedicke, Robert, E. A. Magnier, N. Kaiser, and K. C. Chambers. "The next decade of Solar System discovery with Pan-STARRS." Proceedings of the International Astronomical Union 2, S236 (August 2006): 341–52. http://dx.doi.org/10.1017/s1743921307003419.

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AbstractThe Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) at the University of Hawaii's Institute for Astronomy is a funded project to repeatedly survey the entire visible sky to faint limiting magnitudes (mR ~ 24). It will be composed of four 1.8m diameter apertures each outfitted with fast readout orthogonal transfer Giga-pixel CCD cameras. A single aperture prototype telescopes has achieved first-light in the second half of 2006 with the full system becoming available a few years later. Roughly 60% of the surveying will be suitable for discovery of new solar system objects and it will cover the ecliptic, opposition and low solar-elongation regions. In a single lunation Pan-STARRS will detect about five times more solar system objects than the entire currently known sample. Within its first year Pan-STARRS will have detected 20,000 Kuiper Belt Objects and by the end of its ten year operational lifetime we expect to have found 107 Main Belt objects and achieve ~90% observational completeness for all NEOs larger than ~300m diameter. With these data in hand Pan-STARRS will revolutionize our knowledge of the contents and dynamical structure of the solar system.

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SASAKI, MOKOTO. "VERY HIGH ENERGY PARTICLE ASTRONOMY WITH ALL-SKY SURVER HIGH RESOLUTION AIR-SHOWER DETECTOR." Modern Physics Letters A 19, no. 13n16 (May 30, 2004): 1107–15. http://dx.doi.org/10.1142/s0217732304014446.

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The Ashra detector consists of 3 observational stations installed on the grid of 30-40km distance on the mountains on the Hawaii Big Island, which ensures a large target mass for neutrinos and a large effective aperture for UHECR. An observational station is composed of 12 wide-angle high-precision telescopes, which can completely cover allsky view. In realizing the telescope design, we newly apply the following techniques matured in the other fields: 1) Baker-Nunn optics optimized to keep better than 1 arcmin. resolution in 50° field of view, 2) Electro-static lens image-intensifier tube (IIT) with the resolution matched with that of the above optics, 3) Gated IIT with a fast image shutter, and 4) CMOS image sensor which reads triggered images out of the above IIT. These novel techniques allow us an excellent opportunity for simultaneous observation of air fluorescence and Cerenkov lights with 1 arcmin. resolution in entirely all sky. This will open an interesting field, "Observational Particle Astronomy" by continuously observing TeV gamma-rays, VHE-neutrinos, Knee-CR, and EHECR with the energies from TeV to ZeV in all sky.

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Cruzalèbes, P., R. G. Petrov, S. Robbe-Dubois, J. Varga, L. Burtscher, F. Allouche, P. Berio, et al. "A catalogue of stellar diameters and fluxes for mid-infrared interferometry★." Monthly Notices of the Royal Astronomical Society 490, no. 3 (October 7, 2019): 3158–76. http://dx.doi.org/10.1093/mnras/stz2803.

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Abstract We present the Mid-infrared stellar Diameters and Fluxes compilation Catalogue (MDFC) dedicated to long-baseline interferometry at mid-infrared wavelengths (3–13 $\mu$m). It gathers data for half a million stars, i.e. nearly all the stars of the Hipparcos-Tycho catalogue whose spectral type is reported in the SIMBAD data base. We cross-match 26 data bases to provide basic information, binarity elements, angular diameter, magnitude and flux in the near and mid-infrared, as well as flags that allow us to identify the potential calibrators. The catalogue covers the entire sky with 465 857 stars, mainly dwarfs and giants from B to M spectral types closer than 18 kpc. The smallest reported values reach 0.16 $\mu$Jy in L and 0.1 $\mu$Jy in N for the flux, and 2 microarcsec for the angular diameter. We build four lists of calibrator candidates for the L and Nbands suitable with the Very Large Telescope Interferometer (VLTI) sub- and main arrays using the MATISSE instrument. We identify 1621 candidates for L and 44 candidates for N with the Auxiliary Telescopes (ATs), 375 candidates for both bands with the ATs, and 259 candidates for both bands with the Unit Telescopes (UTs). Predominantly cool giants, these sources are small and bright enough to belong to the primary lists of calibrator candidates. In the near future, we plan to measure their angular diameter with 1 per cent accuracy.

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Frisk, U. O. "First – Far Infrared and Submillimetre Space Telescope." International Astronomical Union Colloquium 123 (1990): 223–30. http://dx.doi.org/10.1017/s025292110007706x.

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AbstractFirst is an element of the ESA long term science program. Currently in a detailed study phase it is foreseen as a large (4.5–8 m) diameter passively cooled telescope equipped with a combination of photometer/camera and very high resolution spectrometers. The spectrometers will utilize both direct detection and heterodyne techniques to cover the wavelength band 85–600 micron. The photometers will have both bolometer and photoconductor detector arrays. FIRST is foreseen to be launched shortly after the year 2000 and will be operated as a facility open to the wide scientific community.

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Melis, A., R. Concu, A. Trois, A. Possenti, A. Bocchinu, P. Bolli, M. Burgay, et al. "SArdinia Roach2-based Digital Architecture for Radio Astronomy (SARDARA)." Journal of Astronomical Instrumentation 07, no. 01 (March 2018): 1850004. http://dx.doi.org/10.1142/s2251171718500046.

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The Sardinia Radio Telescope (SRT) is a 64-m, fully-steerable single-dish radio telescope that was recently commissioned both technically and scientifically with regard to the basic observing modes. In order to improve the scientific capability and cover all the requirements for an advanced single-dish radio telescope, we developed the SArdinia Roach2-based Digital Architecture for Radio Astronomy (SARDARA), a wide-band, multi-feed, general-purpose, and reconfigurable digital platform, whose preliminary setup was used in the early science program of the SRT in 2016. In this paper, we describe the backend both in terms of its scientific motivation and technical design, how it has been interfaced with the telescope environment during its development and, finally, its scientific commissioning in different observing modes with single-feed receivers.

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Ungerechts, H., C. Kramer, B. Lefloch, S. Leon, F. Masset, R. Moreno, G. Paubert, D. Reynaud, A. Sievers, and W. Wild. "Millimeter Continuum Monitoring of Extragalactic Radio Sources with the IRAM 30M Telescope." International Astronomical Union Colloquium 164 (1998): 149–50. http://dx.doi.org/10.1017/s0252921100044948.

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Morgan, D. H. "The UKST Survey of Planetary Nebulae in the Small Magellanic Cloud." International Astronomical Union Colloquium 148 (1995): 415–18. http://dx.doi.org/10.1017/s0252921100022296.

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AbstractThis paper describes the results of searches for planetary nebulae on seven objective prism plates which were taken with the UK 1.2m Schmidt Telescope and cover the entire Small Magellanic Cloud. A total of 62 objects were detected; their spatial distribution is discussed.

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Green, A. J. "The MOST Galactic Plane Survey." Publications of the Astronomical Society of Australia 14, no. 1 (1997): 73–76. http://dx.doi.org/10.1071/as97073.

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AbstractThe Molonglo Observatory Synthesis Telescope (MOST) has been upgraded to increase the diameter of the field of view from 70′ to 2·7°. A survey of the Galactic Plane is proposed to completely cover the region 240° ≤ l ≤ 365°, ∣ b ∣ ≤ 10° with a (1σ) sensitivity of 1–2 mJy. The results will provide a major resource for the investigation of supernova remnants, HII regions and transient radio sources. They will also be correlated with the galaxy search from the HI multibeam survey to be conducted at the Parkes telescope.

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Solanki, S. K., J. C. del Toro Iniesta, J. Woch, A. Gandorfer, J. Hirzberger, A. Alvarez-Herrero, T. Appourchaux, et al. "The Polarimetric and Helioseismic Imager on Solar Orbiter." Astronomy & Astrophysics 642 (September 30, 2020): A11. http://dx.doi.org/10.1051/0004-6361/201935325.

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Aims. This paper describes the Polarimetric and Helioseismic Imager on the Solar Orbiter mission (SO/PHI), the first magnetograph and helioseismology instrument to observe the Sun from outside the Sun-Earth line. It is the key instrument meant to address the top-level science question: How does the solar dynamo work and drive connections between the Sun and the heliosphere? SO/PHI will also play an important role in answering the other top-level science questions of Solar Orbiter, while hosting the potential of a rich return in further science. Methods. SO/PHI measures the Zeeman effect and the Doppler shift in the Fe I 617.3 nm spectral line. To this end, the instrument carries out narrow-band imaging spectro-polarimetry using a tunable LiNbO3 Fabry-Perot etalon, while the polarisation modulation is done with liquid crystal variable retarders. The line and the nearby continuum are sampled at six wavelength points and the data are recorded by a 2k × 2k CMOS detector. To save valuable telemetry, the raw data are reduced on board, including being inverted under the assumption of a Milne-Eddington atmosphere, although simpler reduction methods are also available on board. SO/PHI is composed of two telescopes; one, the Full Disc Telescope, covers the full solar disc at all phases of the orbit, while the other, the High Resolution Telescope, can resolve structures as small as 200 km on the Sun at closest perihelion. The high heat load generated through proximity to the Sun is greatly reduced by the multilayer-coated entrance windows to the two telescopes that allow less than 4% of the total sunlight to enter the instrument, most of it in a narrow wavelength band around the chosen spectral line. Results. SO/PHI was designed and built by a consortium having partners in Germany, Spain, and France. The flight model was delivered to Airbus Defence and Space, Stevenage, and successfully integrated into the Solar Orbiter spacecraft. A number of innovations were introduced compared with earlier space-based spectropolarimeters, thus allowing SO/PHI to fit into the tight mass, volume, power and telemetry budgets provided by the Solar Orbiter spacecraft and to meet the (e.g. thermal) challenges posed by the mission’s highly elliptical orbit.

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Perrodin, D., M. Burgay, A. Corongiu, M. Pilia, A. Possenti, M. N. Iacolina, E. Egron, et al. "Pulsar science at the Sardinia Radio Telescope." Proceedings of the International Astronomical Union 13, S337 (September 2017): 392–93. http://dx.doi.org/10.1017/s1743921317009097.

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AbstractThe Sardinia Radio Telescope (SRT) is a modern, fully-steerable 64-m dish located in San Basilio, Sardinia (Italy). It is characterized by an active surface that allows it to cover a wide range of radio frequencies (300 MHz to 100 GHz). During SRT’s commissioning phase, we installed the hardware and software needed for pulsar observations. Since then, SRT has taken part in Large European Array for Pulsars and European Pulsar Timing Array observations for the purpose of gravitational wave detection. We have installed a new S-band receiver that will allow us to search for pulsars in the Galactic Center. We also plan to combine our efforts to search for Extraterrestrial Intelligence (SETI) with the search for pulsars and Fast Radio Bursts.

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Reid, I. N. "The Second Palomar Sky Survey." Symposium - International Astronomical Union 161 (1994): 29. http://dx.doi.org/10.1017/s0074180900046969.

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The 48-inch Oschin Schmidt telescope at Palomar Observatory was used to obtain the first deep, optical, wide-field survey, covering almost two-thirds of the sky between November 1949 and December 1958 (with plates for the Whiteoak extension, to δ c = −42°, taken in 1964/5). The original survey was taken in two passbands — wide blue and narrow red — on 103a emulsion, and covers one hemisphere in 643 fields with a spacing of 6 degrees between centres. In 1987, plate-taking started for the second Palomar Sky Survey, POSS II, which is intended to cover the northern hemisphere in three passbands, blue (IIIa-J + GG385 filter), red (IIIa-F + RG610) and near-infrared (IVN + RG9). Given the extremely restricted overlap between fields in the old survey, we have followed the example of the UK Schmidt ESO/SERC surveys and have adopted a 5-degree spacing between fields. To date (31.7.93), we have acquired plates of acceptable quality for 597 fields (67%) of the IIIa-J survey, 668 fields (75%) of the IIIa-F and 253 fields (28%) of the IVN.

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Beuzit, J. L., A. Vigan, D. Mouillet, K. Dohlen, R. Gratton, A. Boccaletti, J. F. Sauvage, et al. "SPHERE: the exoplanet imager for the Very Large Telescope." Astronomy & Astrophysics 631 (November 2019): A155. http://dx.doi.org/10.1051/0004-6361/201935251.

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Observations of circumstellar environments that look for the direct signal of exoplanets and the scattered light from disks have significant instrumental implications. In the past 15 years, major developments in adaptive optics, coronagraphy, optical manufacturing, wavefront sensing, and data processing, together with a consistent global system analysis have brought about a new generation of high-contrast imagers and spectrographs on large ground-based telescopes with much better performance. One of the most productive imagers is the Spectro-Polarimetic High contrast imager for Exoplanets REsearch (SPHERE), which was designed and built for the ESO Very Large Telescope (VLT) in Chile. SPHERE includes an extreme adaptive optics system, a highly stable common path interface, several types of coronagraphs, and three science instruments. Two of them, the Integral Field Spectrograph (IFS) and the Infra-Red Dual-band Imager and Spectrograph (IRDIS), were designed to efficiently cover the near-infrared range in a single observation for an efficient search of young planets. The third instrument, ZIMPOL, was designed for visible polarimetric observation to look for the reflected light of exoplanets and the light scattered by debris disks. These three scientific instruments enable the study of circumstellar environments at unprecedented angular resolution, both in the visible and the near-infrared. In this work, we thoroughly present SPHERE and its on-sky performance after four years of operations at the VLT.

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Diercke, Andrea, and Carsten Denker. "Synoptic maps in three wavelengths of the Chromospheric Telescope." Proceedings of the International Astronomical Union 14, A30 (August 2018): 339–41. http://dx.doi.org/10.1017/s1743921319004551.

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Abstracthe Chromospheric Telescope (ChroTel) observes the entire solar disk since 2011 in three different chromospheric wavelengths: Hα, Ca ii K, and He i. The instrument records full-disk images of the Sun every three minutes in these different spectral ranges. The ChroTel observations cover the rising and decaying phase of solar cycle 24. We started analyzing the ChroTel time-series and created synoptic maps of the entire observational period in all three wavelength bands. The maps will be used to analyze the poleward migration of quiet-Sun filaments in solar cycle 24.

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Matsumoto, Toshio. "IRTS: Infrared Telescope in Space." International Astronomical Union Colloquium 123 (1990): 215–22. http://dx.doi.org/10.1017/s0252921100077058.

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AbstractIRTS is a small cryogenically cooled telescope onboard the small space platform SFU (Space Flyer Unit). SFU will be launched with the new Japanese HII rocket on January 1994 and retrieved by the space shuttle.The IRTS telescope has an aperture of only 15 cm diameter, but is optimized to observe diffuse extended infrared sources. Four focal plane instruments are being developed under collaboration between Japan and the U.S.A. IRTS covers a wide wavelength range from near-infrared to submillimeter region, and has a capability for the spectroscopic measurement. Due to newly developed detectors, the sky will be surveyed with very high sensitivities. IRTS will provide valuable data on cosmology, galactic structure, cosmic dust, etc.

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41

Hoag, A. "QSO search by slitless spectroscopy." Symposium - International Astronomical Union 119 (1986): 47–48. http://dx.doi.org/10.1017/s0074180900152210.

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Sandage and I have obtained “grism” plates that redundantly cover one square degree fields centered on ten Selected Areas. We used a grating-prism in the converging beam of the Mayall 4-meter telescope prime focus to photograph 1580 A·mm−1 slitless spectra to a limit of about B = 21.5 (cf. Hoag and Smith 1977).

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Robitaille, Thomas P., and Barbara A. Whitney. "The Galactic star formation rate as seen by the Spitzer Space Telescope." Proceedings of the International Astronomical Union 5, H15 (November 2009): 799. http://dx.doi.org/10.1017/s1743921310011774.

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AbstractWe present preliminary results of a study to determine the star formation rate of the Galaxy using a census of young stellar objects (YSOs) in the Spitzer/GLIMPSE and MIPSGAL surveys, which cover nearly 300 square degrees of the Galactic mid-plane. We find a value of 1.7 M⊙/yr, consistent with independent estimates.

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Suleimanov, V. F., V. V. Neustroev, N. V. Borisov, and I. S. Fioktistova. "Time-Resolved Spectroscopy and Doppler Tomography of UX UMa." International Astronomical Union Colloquium 194 (July 2004): 270. http://dx.doi.org/10.1017/s025292110015314x.

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Medium resolution spectroscopy of nova-like cataclysmic variable UX UMA was performed using the 6-m telescope SAO RAS in April 1999. Obtained spectra cover the total orbital period including eclipse phases and allow us to reproduce the radial velocity curve. The radial-velocity variations of the Hβ emission line are found to have semi-amplitude of about 100 km/s.

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Tan, G. H. "The multi frequency front end: a new type of front end for the Westerbork Synthesis Radio Telescope." International Astronomical Union Colloquium 131 (1991): 42–46. http://dx.doi.org/10.1017/s0252921100013038.

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AbstractThe Westerbork Synthesis Radio Telescope will be equipped with new front ends. These front ends will cover 8 frequency bands in the range from 250 MHz to 8.6 GHz. For the frequency bands above 1.2 GHz the sensitivity of the instrument will be drastically improved. Two independent local oscillator systems make it possible to observe in two frequency bands simultaneously.

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Liu, K., R. E. Skelton, and J. P. Sharkey. "Modeling Hubble Space Telescope flight data by Q-Markov cover identification." Journal of Guidance, Control, and Dynamics 17, no. 2 (March 1994): 250–56. http://dx.doi.org/10.2514/3.21190.

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Legrand, Michel. "Studying “Luna Incognita”: The Region Near the South Pole." International Astronomical Union Colloquium 98 (1988): 146. http://dx.doi.org/10.1017/s025292110009254x.

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AbstractA region of approximately 270 000 km2 near the south pole of the Moon has not been mapped by spacecraft and Dr John Westfall of ALPO proposed the “Luna Incognita” programme in 1972 to try to cover this area. A brief summary of the problems of observing this limb region was given, together with the author’s experience using the T60 and 1-m telescopes at Pic du Midi.

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Hajjar, Roger, François R. Querci, and Monique Querci. "The NORT: Network of Oriental Robotic Telescopes." International Astronomical Union Colloquium 183 (2001): 33–38. http://dx.doi.org/10.1017/s025292110007857x.

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AbstractIn this paper, we present the NORT, a network of oriental robotic telescopes originally proposed in 1993 by Querci & Querci to study stellar variability. The NORT project covers all of northern Africa and Asia near the tropic of Cancer. The interest generated among a number of astronomers in countries from the Arab World and Asia offers a solid basis for the rebirth of astronomy and astrophysics and space sciences in developing countries. The number of national projects for telescopes in different countries makes the NORT a framework of choice to coordinate and stimulate these separate efforts by the creation of a NORT steering committee.

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Teräsranta, H., M. Tornikoski, and E. Valtaoja. "Long Term Monitoring of AGN with the Metsähovi and SEST Telescopes." Symposium - International Astronomical Union 159 (1994): 410. http://dx.doi.org/10.1017/s0074180900175989.

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The monitoring of extragalactic sources with the Metsähovi radio telescope started in 1980. Since then we have made more than 21000 observations at 12, 22, 37, 77 and 87 GHz. Currently we have 84 sources in our sample which should be observed once a month at 22 and 37 GHz. The sample is limited to declinations above −10 degrees. In most cases our sampling is dense enough to cover all the outbursts at these two frequencies, because our earlier observations have shown the timescales of a typical outburst at 22 and 37 GHz to be from 0.3 to several years.

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Morgan, D. H., Q. A. Parker, and S. Phillipps. "Deep Wide-field Hα Images of the Magellanic Clouds." Symposium - International Astronomical Union 190 (1999): 95–96. http://dx.doi.org/10.1017/s0074180900117450.

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A new Hα survey of the Magellanic Clouds which is being carried out on fine-grained Tech-Pan emulsion with the UK 1.2m Schmidt Telescope will have the best combination of depth and resolution of any that cover such a wide area in and around the Magellanic Clouds. Preliminary results show that the films will provide identifications of new emission-line stars and nebulae.

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Ueno, Munetaka, Fumiaki Tsumuraya, and Yoshihiro Chikada. "PtSi IR Array in Mosaic Configuration." Symposium - International Astronomical Union 167 (1995): 117–21. http://dx.doi.org/10.1017/s0074180900056357.

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The rapid progress in the focal plane technology enables us to use large format infrared sensors, such as 256 × 256 InSb/HgCdTe and 1040 × 1040 PtSi arrays. Infrared two-dimensional sensors make possible not only the imaging observations but a deep detection limit. The development of a large format infrared array is one of the most important breakthroughs in observational astronomy.We propose to build a mosaic infrared camera for the SUBARU 8-m telescope. The SUBARU telescope is designed to reach a diffraction limited image at infrared wavelengths with a wide field of view (six arcsec at the Cassegrain focus). The camera is designed to cover the entire field of view with PtSi infrared sensors and to employ a weighted shift-and-add operation and a real-time image processing. The efficiency of the mosaic infrared camera and power of the 8-m telescope have a strong potential to meet challenging problems. Most of the regions of the near infrared sky are not covered with enough sensitivity. It is essential to conduct infrared deep and wide surveys.

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Journal articles on the topic 'Telescopic cover'

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