Post-Outburst Spectroscopy of Classical Novae

1977 ◽  
Vol 42 ◽  
pp. 201-213
Author(s):  
S. Wyckoff ◽  
P.A. Wehinger
Keyword(s):  
Emission Line ◽  
Image Tube ◽  
Classical Novae ◽  
Binary Nature ◽  
Minimum Light

SIT Vidicon spectra (3500 - 5100 Å) with time resolutions of several minutes and spectral resolutions of 6 Å have been obtained of a sample of old novae at minimum light. For comparison, spectra of SCO X-1 (V818 Sco) are also presented. Velocity-resolved image-tube spectra of RR Pic 1925 indicate Doppler variations in the He II λ4686 emission line with a period ~ 3 hours, thus confirming the binary nature of RR Pic.

Spectropolarimetry of V854 Centauri at minimum light - Clues to the geometry of the dust and emission-line region

1992 ◽  
Vol 103 ◽  
pp. 1652 ◽  
Author(s):  
Barbara A. Whitney ◽  
Geoffrey C. Clayton ◽  
Regina E. Schulte-Ladbeck ◽  
Marilyn R. Meade
Keyword(s):  
Emission Line ◽  
Minimum Light ◽  
Line Region

scholarly journals Optical Observations of Recent Novae

1977 ◽  
Vol 42 ◽  
pp. 149-181
Author(s):  
B. Wolf
Keyword(s):  
Light Curve ◽  
Absolute Magnitude ◽  
Optical Observations ◽  
Variable Amplitude ◽  
Classical Novae ◽  
Binary Nature ◽  
M 10 ◽  
Speed Of Evolution

AbstractThe observations of two rather different classical novae, V 1500 Cyg (= Nova Cyg 1975) and NQ Vul (= Nova Vul 1976), are presented and compared. Nova Cyg 1975 is outstanding with respect to absolute magnitude (M = -10), range of brightening (Δm = 19), and speed of evolution (t3= 3.6 days). Its prenova object had to be fainter than about magnitude 9. The corresponding values for Nova Vul 1976 are rather conservative (M≈-7.5, Δm ≈ 12, t3=40 days, absolute magnitude of the prenova ≈4.5). The light curve of Nova Cyg 1975 is very smooth. Some superimposed photometric variations of a small and slightly variable amplitude of a period of 3.4 hours are most naturally ascribed to a binary nature of Nova Cyg 1975. Nova Vul 1976 has a completely different lighteurve with extremely strong rapid irregular variations of considerably amplitude. There is a remarkable second maximum about 14 days after discovery.

scholarly journals Neo-R1000: A Fast And Efficient Compact Spectrograph For Emission Line Objects Study At Bosscha Observatory

2016 ◽  
Vol 27 (1) ◽  
pp. 1-8
Author(s):  
Hakim L Malasan ◽  
Imanul Jihad ◽  
Robiatul Muztaba ◽  
Irham T Andika ◽  
Evaria Puspitaningrum ◽  
...  
Keyword(s):  
Emission Line ◽  
High Speed ◽  
Focal Length ◽  
Ccd Camera ◽  
Halogen Lamp ◽  
Be Stars ◽  
Classical Novae ◽  
Transmission Grating ◽  
Cathode Tube ◽  
High Flexibility

In 2015, the Institute Teknologi Bandung (ITB) signed a Memorandum of Understanding with Sangyou Kyoto University (KSU). One realization of collaboration between ITB and KSU is observational program of Novae using a compact spectrograph NEO-R1000 (Novae and Emission line Objects with Resolution of 1000). This spectrograph is mounted at the Celestron C-11 (F/10.0) reflector and supported by a Losmandy G-11 equatorial mounting inside the GAO-ITB sliding roof building, Bosscha observatory, Lembang. The unique configuration of this spectrograph is the employment of mirror collimator and camera lens with focal length ratio of 3:1. This makes it has high speed characteristics. A slit width of 6.5 μm (4.7” @ C-11 reflector ) is combined with a fixed transmission grating of 600 grooves/mm and equipped with a ST-8 XME CCD camera (9 μm per pixel, 1530 × 1024 pixels), resulting in a resolution of R≈ 1000 at a wavelength of 5800 Å with effective spectrum wavelength coverage Δl 4000-8000 Å. NEO-R1000 spectrograph has additional peripherals such as a Fe-Ne-Ar hollow cathode tube (HTC) which is used as a comparison source. We take flat-field spectrum by using an acrylic board and a halogen lamp. The main primary aim of this spectrograph is to observe the Classical Novae in the southern sky as part of Collaborative Spectroscopic Observations for the Detection of Molecules in Classical Novae. This spectrograph can also be used to observe other emission line objects such as Planetary Nebulae, Comets, P Cygni star type, WR stars and Be stars. In June 2015, this spectrograph was successfully used to observe Nova Sgr 2015 no 2. Further developments of this spectrograph includes constructing a rotator to be attached to the flange of telescope to ensure high flexibility in observation of extended objects. In the future, a fiber optic connecting output pupil with the entrance slit of the spectrograph will be deployed to improve observational effectivity while reducing the load of spectrograph on telescope.

scholarly journals Infrared Lines in Peculiar Emission-Line Stars

1976 ◽  
Vol 72 ◽  
pp. 155-156 ◽  
Author(s):  
Y. Andrillat ◽  
L. Houziaux
Keyword(s):  
Emission Line ◽  
Infrared Spectra ◽  
Emission Lines ◽  
Image Tube ◽  
Line Intensities ◽  
Critical Phase ◽  
Relative Abundances

An image-tube Cassegrain spectrograph, equipped with an S-1 photocathode enabled us to obtain infrared spectra of peculiar emission-line objects, as V 1016 Cyg, HBV 475, HD 51585, HD 45677, XX Oph and CI Cyg. Many of these objects display emission lines of H I, He I, He II, O I, N I, Ca II [S II] [S III], [Fe II]. The line intensities can be used together with data from other parts of the spectrum to determine relative abundances of these ions in the shells of these objects, which may be at a critical phase of their evolution.

scholarly journals Infrared Spectra of T Tau Stars and Related Objects

1975 ◽  
Vol 67 ◽  
pp. 117-122
Author(s):  
G. I. Shanin ◽  
V. S. Shevchenko ◽  
A. G. Shcherbakov
Keyword(s):  
Emission Line ◽  
Infrared Spectra ◽  
Single Stage ◽  
Atomic Line ◽  
Image Tube ◽  
Spectroscopic Observations ◽  
The Crimea ◽  
T Tau

Four T Tau stars and related objects (RY Tau, T Tau, AB Aur and V1057 Cyg) have been included in our spectroscopic programme since 1973. The present paper is concerned with the spectroscopic observations made at the Crimea with the single-stage image tube S1. Tentative atomic line identifications are given for programme stars. CaII and OI emission line equivalent widths and profiles are presented for RY Tau, T Tau and AB Aur. The λ10830 Å line of neutral helium has shown P Cyg-type features for T Tau and V 1057 Cyg.

scholarly journals Radial Velocities of SS Cygni

1979 ◽  
Vol 53 ◽  
pp. 489-493
Author(s):  
R. J. Stover
Keyword(s):  
Radial Velocity ◽  
Emission Line ◽  
Absorption Line ◽  
Orbital Period ◽  
Radial Velocities ◽  
Orbital Elements ◽  
Velocity Measurements ◽  
Light Spectrum ◽  
Minimum Light ◽  
Spectroscopic Binary

SS Cygni was found by Joy (1956) to be a spectroscopic binary with an orbital period of about 6-1/2 hours. At minimum light it has mv=12 and is the brightest member of the dwarf nova class of variables. The minimum light spectrum reveals faint, narrow absorption lines of a G- or K-type star along with strong, broad emission lines of hydrogen, helium, and calcium which are produced by an accretion disk surrounding a white dwarf star. Joy’s radial velocities were not very accurate. Nevertheless, he was able to estimate the orbital elements, finding 115 km/s for the absorption line K-velocity and 122 km/s for the emission line K-velocity. In addition, he derived an orbital period of 0276244. Later minimum light observations by Walker and Chincarini (1968) were too few to be able to improve the orbital elements. Kiplinger (1979) refined the emission line radial velocities but was not able to remeasure the faint absorption line spectrum. This paper presents new radial velocity measurements of both the emission and absorption line spectra of SS Cygni at minimum light, and is the first thorough investigation of this star’s radial velocity variations in more than 20 years. The accuracy of the radial velocity curves has been greatly improved. We also find that Joy’s orbital period is in error by nearly two minutes.

scholarly journals Possible Binary Nature of the Emission-Line Variable Object V 1329 Cygni (= HBV 475)

1977 ◽  
Vol 42 ◽  
pp. 383-385
Author(s):  
Jiři Grygar ◽  
Ladislav Hric ◽  
Drahomír Chochol
Keyword(s):  
Emission Line ◽  
Time Evolution ◽  
Emission Lines ◽  
Type Star ◽  
High Dispersion ◽  
Early Type ◽  
Composite Spectrum ◽  
Binary Nature ◽  
Objective Prism

The peculiar emission-line object V 1329 Cyg was discovered by Kohoutek (1969), who detected in his objective-prism spectrograms an increasing brightness and the presence of emission lines. High dispersion spectra revealed more than 200 emissions of hydrogen, helium, ionized metals and forbidden lines of oxygen, neon, etc. (Crampton et al., 1970; Andrillat, 1970). The object exhibits the composite spectrum of a hot early-type component and a cold M-type star. Its time evolution in a two-colour diagram is seen in Fig. 1.

FeXIV Line Emission Polarization of the July 11, 1991 Solar Corona

1994 ◽  
Vol 144 ◽  
pp. 541-547
Author(s):  
J. Sýkora ◽  
J. Rybák ◽  
P. Ambrož
Keyword(s):  
High Resolution ◽  
Solar Corona ◽  
Emission Line ◽  
Solar Eclipse ◽  
White Light ◽  
Preliminary Analysis ◽  
Line Emission ◽  
Total Solar Eclipse ◽  
Degree Of Polarization ◽  
High Resolution Images

AbstractHigh resolution images, obtained during July 11, 1991 total solar eclipse, allowed us to estimate the degree of solar corona polarization in the light of FeXIV 530.3 nm emission line and in the white light, as well. Very preliminary analysis reveals remarkable differences in the degree of polarization for both sets of data, particularly as for level of polarization and its distribution around the Sun’s limb.

Structuring, Motions and Shapes of Corona Emission Line Profiles

1994 ◽  
Vol 144 ◽  
pp. 421-426
Author(s):  
N. F. Tyagun
Keyword(s):  
Emission Line ◽  
Filling Factor ◽  
Direct Relationship ◽  
Coronal Plasma ◽  
Line Of Sight ◽  
Line Profiles ◽  
The Difference ◽  
Yellow Line ◽  
Red Line

AbstractThe interrelationship of half-widths and intensities for the red, green and yellow lines is considered. This is a direct relationship for the green and yellow line and an inverse one for the red line. The difference in the relationships of half-widths and intensities for different lines appears to be due to substantially dissimilar structuring and to a set of line-of-sight motions in ”hot“ and ”cold“ corona regions.When diagnosing the coronal plasma, one cannot neglect the filling factor - each line has such a factor of its own.

White-Light Coronal Structures: Streamers and CMEs

1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner
Keyword(s):  
Emission Line ◽  
Electron Density ◽  
White Light ◽  
Coronal Mass Ejections ◽  
X Rays ◽  
Solar Cycles ◽  
Temperature Function ◽  
X Ray ◽  
Eclipse Observations ◽  
Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

Sign in / Sign up

Export Citation Format

Share Document