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1.
This paper describes a real-time spectrum analyser with on-line definition of the confidence levels built at Trieste Observatory
for a research program on periodical components of unknown period in optical sources. The system is realized by a photon counting
photometer on-line to a computer that elaborates in real-time the data from the photometer and displays the spectrum of the
source measured. The spectrum is normalized to unity mean value and the display is calibrated by the confidence levels relative
to the
distribution of the spectrum displayed. Some experimental data show the performance of the machine that operates in real-time
at full efficiency up to 160 Hz.
Work supported by Consiglio Nazionale delle Ricerche, Gruppo Nazionale di Astronomia, Settore Tecnologie Astronomiche. Trieste
Observatory — Instruments and Data Processing Group (1/76). 相似文献
2.
The note shows how to estimate accurately the optimum measuring time in the measurement of a periodical optical source by
means of a synchronous photometer affected by phase-tracking error.
The procedure used can be easily generalized to sources or signal patterns not considered here.
The optimum number of scans to be averaged results to be typicallyN
opt≈0.5r/ɛ for an optical source of Lorentzian signal pattern, wherer is the duty cycle of the pulsed component and ɛ the relative truncation error of the local sync to the source period.
Work supported by Consiglio Nazionale delle Ricerche, Gruppo Nazionale di Astronomia, Settore Tecnologie Astronomiche. Trieste
Observatory — Instruments and Data Processing Group (4/76). 相似文献
3.
This note demonstrates the application of a rigorous procedure for estimating the limiting standard deviation in the absolute timing, of periodic sources of known period, to the problem of the evaluation of the effects of the main source and instrumental parameters. The procedure is used to examine the case of the optical pulsar NP 0532. The results are given in diagrammatic form.Work supported by Consiglio Nazionale delle Ricerche, Gruppo Nazionale di Astronomia, Settore Tecnologie Astronomiche. Trieste Observatory-Instruments and Data Processing group (2/76). 相似文献
4.
Yang Tinggao 《时间频率学报》1995,(1)
根据对鬼星团中Ｊｏｈｎｓｏｎ测光标准星的观测，我们研究了北京天文台６０ｃｍ望远镜直流光电光度计ＵＢＶ测光系统的转换方程．应用该方程推算了对三颗变星观测得到的ＵＢＶ星等，讨论了所得光变曲线的精度，并与较差方法所得结果进行了比较 相似文献
5.
Results of observations of 14 asteroids are reported; all of them, except 181 Eucharis, have been previously observed at least once. V photoelectric lightcurves were obtained from September 1982 to June 1983 at the Astronomical Observatory of Torino and at the Astrophysical Observatory of Catania. Part of this program aims to obtain complete lightcurves and, when possible, phasecurve information and to determine amplitudes and V magnitudes at different longitudes for a selected group of asteriods, in order to enlarge the set of known rotational axis directions. 相似文献
6.
Two events of outburst of Garnet Hale - Bopp occurred on Oct. 9,1996 and Nov. 13,1996 are observed by means of photoelectric integrating photometer mounted on the 60cm reflector of Purple Mountain Observatory. The results are shown in Tab. 3, Fig. 1 (Oct. 9, 1996) and in Tab.4,Fig.2(Nov.13,1996). 相似文献
7.
David S. McDougal 《Solar physics》1971,21(2):430-438
During the 7 March, 1970, total eclipse of the Sun, the NASA Langley Research Center's Satellite Photometric Observatory (SPO) was used to measure the solar corona from Miahuatlan, Mexico. The SPO is equipped with a 24-inch Cassegrainian telescope, a four-channel photoelectric photometer, a Wollaston prism, and a rotating half-wave plate. Simultaneous measurements were made of the two orthogonal components of coronal light in the B and R bands of the UBVRI system. A 1-minute arc aperture was scanned from the lunar disk center out to five solar radii in a series of spirals of gradually increasing radius. For the first time, simultaneous multicolor intensity, degree, and angle of polarization profiles are computed from photoelectric measurements. Comparison of the variations of the measurements for each spiral scan yield a detailed picture of the intensity and polarization features in the K corona. 相似文献
8.
We present the photoelectric observations of the asteroids 26 Proserpina, 194 Prokne, 287 Nephthys, and 554 Peraga, performed in the years 1977–1978 at the Astronomical Observatory of Torino. The resulting synodic rotation periods are, for Proserpina, 13h13; Prokne, 15h67; and Peraga, 13h63. The period of Nephthys is possibly ～7h or the double. A tentative value for the phase coefficient of Peraga was found: 0.043 mag/degree. 相似文献
9.
Krešimer Pavlovski 《Icarus》1976,29(4):509-512
Blue-violet photoelectric photometry of a reappearance of Io on 10 October 1974 is presented. Observations were made with a single-beam photometer on the Hvar Observatory 65-cm telescope. A brightness anomaly of about 0.15 and 0.25 mag in V and B, respectively, was detected, but owing to the relativity large estimated errors, 0.04 and 0.05 mag, respectively, detection is regarded astentative. The wavelength dependence, reported previously by some investigators, was confirmed. The urgent need of multicolor photometry is briefly stressed. 相似文献
10.
B. N. Ashoka Kumar V. C. Babu S. Seetha V. Girish S. K. Gupta Ram Sagar S. Joshi P. Narang 《Journal of Astrophysics and Astronomy》2001,22(1):131-144
The design and performance of a portable three channel photometer installed at the Uttar Pradesh State Observatory (UPSO),
Naini Tal is described. The photometer is modular and the whole unit can be disassembled as individual channels such that
the system can also be used as a single channel or two channel photometer. The system also has provision to monitor a guide
star. The instrument was put into operation since November 1999 on the 1m Sampurnanand telescope at UPSO, Naini Tal. Since
then, it is used extensively for the ‘Survey of rapidly oscillating Ap (roAp) stars in the northern sky’ from UPSO. Observational
results using this new photometer in its initial phase of operation are discussed. The advantage of having continuous sky
measurement is demonstrated. 相似文献
11.
Fiorella Castelli 《Astrophysics and Space Science》1977,49(1):179-197
The identification, the equivalent widths, the profiles and the radial velocities as deduced from 18 spectra of Aurigae are presented and discussed.The observations have been made at the Astronomical Observatory of Haute Provence (CNRS). This work has been partially supported by a contract of Consiglio Nazionale delle Ricerche (CNR). 相似文献
12.
本文介绍了北京天文台新研制的光电光度计。本光度计是带有微计算机星天交替式的。可通过计算机控制实现星天和滤光片自动转换。可以很方便地进行随机采集和连续采集,可以实时显示数据和处理观测结果。已经正规观测两年多,取得了一批观测成果,精度可达±0.003~m,能很好地归化到国际系统。 相似文献
13.
14.
Anna M. Nobili Gian Luca Comandi Suresh Doravari Donato Bramanti Rajeev Kumar Francesco Maccarrone Erseo Polacco Slava G. Turyshev Michael Shao John Lipa Hansjoerg Dittus Claus Laemmerzhal Achim Peters Jurgen Mueller C. S. Unnikrishnan Ian W. Roxburgh Alain Brillet Christian Marchal Jun Luo Jozef van der Ha Vadim Milyukov Valerio Iafolla David Lucchesi Paolo Tortora Paolo De Bernardis Federico Palmonari Sergio Focardi Dino Zanello Salvatore Monaco Giovanni Mengali Luciano Anselmo Lorenzo Iorio Zoran Knezevic 《Experimental Astronomy》2009,23(2):689-710
“Galileo Galilei” (GG) is a small satellite designed to fly in low Earth orbit with the goal of testing the Equivalence Principle—which
is at the basis of the General Theory of Relativity—to 1 part in 1017. If successful, it would improve current laboratory results by 4 orders of magnitude. A confirmation would strongly constrain
theories; proof of violation is believed to lead to a scientific revolution. The experiment design allows it to be carried
out at ambient temperature inside a small 1-axis stabilized satellite (250 kg total mass). GG is under investigation at Phase
A-2 level by ASI (Agenzia Spaziale Italiana) at Thales Alenia Space in Torino, while a laboratory prototype (known as GGG)
is operational at INFN laboratories in Pisa, supported by INFN (Istituto Nazionale di fisica Nucleare) and ASI. A final study
report will be published in 2009. 相似文献
15.
Photoelectric lightcurves of 21 asteroids are presented. The observations were carried out from 1978 to 1982 at the Astronomical Observatory of Torino (at the Astrophysical Observatory of Catania for 137 Meliboea). For 10 objects a reliable rotation period has been obtained, while for two others a rough estimate is given. In several cases the analysis of the observed amplitudes versus the ecliptic longitudes indicates the most favorable future oppositions for period and/or pole determination. For some asteroids transformations to UBV Standard System were performed. 相似文献
16.
对北京天文台新近改造成的三通道高速光度计的结构和性能进行介绍,并给出了在兴隆站85公分望远镜的一些实测结果. 相似文献
17.
The design, construction and use of a multi-purpose photometer is discussed. It is intended to work between 9000 Å to 3700 Å on the 25-inch Turner-Newall refractor of the Athens National Observatory and eventually on the Greek 48-inch reflector now under construction. 相似文献
18.
在1984年2—3月,用美国McDonald天文台91cm反射镜的UBV测光系统和云南天文台35厘米反射镜V色测光系统,对Archer 1959年在后发座用照相方法发现的24颗变(双)星中的17颗进行了观测研究,全部没有大于0~m.07的光变,其中12颗的连续观测时间长于半个周期以上,因而至少它们不是原定周期和变幅的那种变星。其他5颗或Archer未给周期,或观测复盖不够半个周期,未能肯定。最后给出这些星和比较星的星等和色指数。 相似文献
19.
Two topics of research, namely extragalactic and variable star studies represent the main attitudes of astronomical work at the Helwan Observatory.The 74 inch telescope at Kottamia (476 m, 2h.12, 29°.93 N) some 60 km to the east of Cairo is the main instrument. Some other auxiliary equipment (Cassegrain and echelle spectrographs, Westinghouse and Japanese cameras and photoelectric photometer) can be attached at both Cassegrain and Newtonian foci.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
20.
Adolfo L. Méndez Berhondo Ana K. Díaz Rodríguez P. Zlobec Lupe Cuendias Pérez 《Astrophysics and Space Science》2013,346(2):301-306
The dynamic characteristics of solar metric radio bursts with intermediate drifting patterns (fiber bursts) as they evolve at fixed frequency are examined. The data were recorded using the radio polarimeter of the Trieste Astronomical Observatory. The aim is to determine if the underlying process can be described as a deterministic chaos. Correlation dimensions and Hurst exponent are estimated showing deterministic chaotic system of low dimension. 相似文献