Results 11 to 20 of about 241,534 (269)
Hard synchrotron BL Lacs: the case of 1ES 1101-232 [PDF]
, 2000 The bright X-ray selected BL Lac object 1ES1101--232 shows a flat X-ray spectrum, making it detectable with high statistics over the wide BeppoSAX energy range.
Caccianiga, Alessandro +4 more
core +3 more sources
Conceptual Design of the NISS onboard NEXTSat-1 [PDF]
Journal of Astronomy and Space Sciences, 2014 The NISS onboard NEXTSat-1 is being developed by Korea astronomy and space science institute (KASI). For the study of the cosmic star formation history, the NISS performs the imaging spectroscopic observation in the near-infrared range for nearby ...
Woong-Seob Jeong +17 more
doaj +1 more source
Light Curve Analysis of SAO23229 [PDF]
Journal of Astronomy and Space Sciences, 1993 We have made UBV light curves of a newly discovered eclipsing binary, SAO23229 at Sobaeksan Astronomy Observatory. We determined a minimum light time of HJD2448636.1170+/-0.0005 that is 3 minutes later than predicted time, and founda peculiar light ...
Ho-Il Kim +3 more
doaj
Close Binary System GO Cyg [PDF]
, 2011 In this study, we present long term photometric variations of the close binary system \astrobj{GO Cyg}. Modelling of the system shows that the primary is filling Roche lobe and the secondary of the system is almost filling its Roche lobe.
B. Kalomeni +48 more
core +2 more sources
Time variation of the fine structure constant in the early universe and the Bekenstein model [PDF]
, 2007 We calculate bounds on the variation of the fine structure constant at the time of primordial nucleosynthesis and at the time of neutral hydrogen formation. We use these bounds and other bounds from the late universe to test Bekenstein model.
Antoniadis +106 more
core +3 more sources
Roche Model and Absolute Dimensions of the Eclipsing Binary Y Cam with a Pulsating Component [PDF]
Journal of Astronomy and Space Sciences, 2002 We performed CCD photometric observations of the eclipsing binary Y Cam with a pulsating component, for 16 nights from November 2000 to May 2001 using a V filter attached to the 61-cm reflector at Sobaeksan Optical Astronomy Observatory.
J. W. Lee +4 more
doaj +1 more source
Report of combined meeting of Commissions 8 (Meridian Astronomy), 19 (Variation Of Latitude) and 31 (Time), August 21. 9.30 a.m [PDF]
Transactions of the International Astronomical Union, 1950 The President outlined the history of the Ross photographic zenith tube, saying that it was originally designed for measurement of the variation of latitude by Dr Ross, and later adapted to the determination of time by Dr Littel. The success of the instrument and its possible application to various problems in positional astronomy made it of interest ...
openaire +1 more source
The stability of the optical flux variation gradient for 3C120
, 2015 New $B$- and $V$-band monitoring in 2014 $-$ 2015 reveals that the Seyfert 1 Galaxy, 3C120, has brightened by a magnitude of $1.4$, compared to our campaign that took place in 2009 $-$ 2010.
Chini, Rolf +4 more
core +1 more source
An estimate of the time variation of the O/H radial gradient from planetary nebulae [PDF]
, 2002 Radial abundance gradients are a common feature of spiral galaxies, and in the case of the Galaxy both the magnitude of the gradients and their variations are among the most important constraints of chemical evolution models.
Alibés +47 more
core +2 more sources
Cepstrum Analysis of Terrestrial Impact Crater Records [PDF]
Journal of Astronomy and Space Sciences, 2008 Study of terrestrial impact craters is important not only in the field of the solar system formation and evolution but also of the Galactic astronomy. The terrestrial impact cratering record recently has been examined, providing short- and intermediate ...
Heon-Young Chang, Cheongho Han
doaj +1 more source