Search Publications
The Source of a coronal mass ejection in a decayed solar active region
Gosain, Sanjay; Prasad Choudhary, Debi; Srivastava, Nandita
We have studied the source of a coronal mass ejection (CME), which occurred in a decayed active region NOAA 7978 on 19 October, 1996. The active region NOAA 7978 first appeared on the solar disk on 2 June, 1996 and made more than five disk passages before it decayed. The event analysed in this paper was observed during fifth disk passage. We have …
Kinematic analysis of spiral structures in the local disk
Chiba, M.; Gouda, N.; Yano, T.
We present a method, based on the kinematic analysis of the Galactic disk stars near the Sun, to clarify whether the internal motions of the stellar system in spiral arms follow those expected in the density wave theory. The method is based on the linear relation between the phases of spatial positions and those of epicyclic motions of stars, as p…
Nice Observatory CCD measurements of visual double stars (4th series)
Gili, R.; Salaman, M.; Morlet, G.
We present 176 measurements of 167 visual double stars, made in 2000 and 2001 with the 50 cm refractor of the Nice Observatory and attached CCD camera, using an algorithm based on the adjustment of a tridimensional mathematical surface (Table 1). Position angle, angular separation and magnitude difference are given. 33 new binaries (HDS and TDS) d…
Extending the limits of globule detection. ISOPHOT Serendipity Survey observations of interstellar clouds II
Juvela, M.; Lisenfeld, U.; Kiss, Cs. +3 more
Small isolated clouds were discovered by the ISOPHOT 170 mu m Serendipity Survey (ISOSS) as faint I170<13 MJy sr-1 FIR sources. One of them is ISOSS J20246+6540, a cold (Td~ 14.5 K) pointlike ISOSS source without an IRAS pointsource counterpart. In the Digitized Sky Survey B band it is seen as a 3 arcmin size bi…
Multi-wavelength observations of a flare spray and CME of 1 October 2001
Li, Hui; You, Jianqi; Yu, Xingfeng +1 more
Using the Multi-channel Infrared Solar Spectrograph (MISS) at the Purple Mountain Observatory (PMO), we obtained the Hα , Ca Ii 8542 Å, He I 10 830 Å spectra and slit-jaw Hα images of a large dramatic flare spray near the south-west solar limb on 1 October 2001. For this event, we also got Extreme-Ultraviolet (EUV) images at 171 Å from TRACE and 1…
Analysis of a delta Scuti spectroscopic binary: CQ Lyncis
Carrier, F.; Udry, S.; Ginestet, N. +2 more
CQ Lyn is a new double-lined spectroscopic binary, composed of an Am delta Scuti and a solar-like star, with an orbital period of 12.50736 d and a zero-eccentricity. Physical parameters of both stars are well constrained. The characteristics of the primary are the following: M=1.714 Msun, Teff=6760 K, log L/Lsun= 1…
A lopsided chemically distinct nucleus in NGC 5055
Sil'chenko, O. K.; Afanasiev, V. L.
Kinematics and stellar population properties in the center of nearby Sbc galaxy NGC 5055 are studied with the Multi-Pupil Spectrograph of the 6 m telescope of the Special Astrophysical Observatory of Russian Academy of Sciences (SAO RAS). We confirm the rotation and stellar velocity dispersion asymmetries along the major axis reported earlier by o…
Nature of OH maser and SiO thermal emission towards carbon star: IRAS 05373-0810 (V1187 Ori)
Omont, A.; Szczerba, R.; Szymczak, M. +1 more
We present observational evidence that IRAS 05373-0810 is a genuine carbon star with an ISO SWS spectrum closely resembling that of R Scl. Modelling of the spectral energy distribution of IRAS 05373-0810 suggests that the star has luminosity of order of 8000 Lsun and loses mass at a rate of about 2-3*E-7 Msun yr
A study of opacity in SOHO-SUMER and SOHO-CDS spectral observations. III. The validity of the escape probability model
Fischbacher, G. A.; Loch, S. D.; Summers, H. P.
The assumptions underpinning escape probability and absorption factor methods for describing spectral emission from optically thick plasmas, are addressed to test the range of validity of the associated expressions and to develop them for use within non-stratified atmospheres which include plasma flow and line blending. It is found that for modera…
Lasers without inversion (LWI) in Space: A possible explanation for intense, narrow-band, emissions that dominate the visible and/or far-UV (FUV) spectra of certain astronomical objects
Sorokin, P. P.; Glownia, J. H.
The optical or far-UV (FUV) spectra of certain objects in Space are completely dominated by one or two spectrally narrow emission lines, strongly suggesting that laser action of some kind occurs in these objects. However, the electronic level structures of the atoms/ions producing these emissions preclude the possibility of maintaining population …