Co-ordinated Optical and Radio Observations of Symbiotic Stars

AbstractWe present preliminary results from absolutely flux-calibrated optical spectroscopy, together with 5 GHz radio flux measures of 17 symbiotic stars. The data were obtained quasi-simultaneously using the Manchester Echelle Spectrograph on the Isaac Newton Telescope, La Palma between 1988 September 20 and 24, and the Broad Band Interferometer at Jodrell Bank during 1988 October. This represents the largest sample of these stars observed in this way to date. Distances are calculated using visual extinctions and are compared with other quoted values. In general, the agreement is surprisingly good. Plots of individual line luminosities vs. radio luminosity indicate that the D-type (dusty) symbiotics (both also proto-planetary nebulae) have far higher radio luminosities than S-types (stellar) for comparable recombination and forbidden line luminosities. This may however be due to underestimation of optical line luminosities for the D-types as the circumstellar extinction contribution is uncertain. The single D’-type (cool dust, yellow secondary) lies at the low luminosity end of the S-type region. ‘Very slow novae’ in our sample lie in both groups.

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The La Palma Data Archive

International Astronomical Union Colloquium ◽

10.1017/s0252921100003213 ◽

1989 ◽

Vol 110 ◽

pp. 139-140

Author(s):

Chris Benn

Keyword(s):

Data Archive ◽

Isaac Newton ◽

La Palma ◽

Data Archives ◽

International Ultraviolet Explorer ◽

Isaac Newton Telescope ◽

The Republic ◽

Volcanic Caldera ◽

The Uk ◽

William Herschel

The Observatorio del Roque de los Muchachos is perched atop a volcanic caldera on the island of La Palma in the Canary Islands, 400 km off the coast of North Africa. Three of the telescopes at the observatory are products of a collaboration between the UK, the Netherlands, Spain and the Republic of Ireland. They are the 1.0-m Jacobus Kapteyn Telescope, the 2.5-m Isaac Newton Telescope and the 4.2-m William Herschel Telescope (which saw first light in July 1987)1. The telescopes are computer controlled (running under ADAM software), and the observations are recorded primarily in electronic form. Recognising the success of astronomical-satellite data archives, such as that generated by the International Ultraviolet Explorer, a La Palma Data Archive has been established at the Royal Greenwich Observatory. The archive will be used by astronomers wishing to exploit data obtained by other observers, by engineers interested in the performance of telescope and instruments under varying conditions, and for monitoring the way in which the telescope is used.

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High Resolution Spectroscopy of Symbiotic Stars

International Astronomical Union Colloquium ◽

10.1017/s0252921100069062 ◽

1990 ◽

Vol 122 ◽

pp. 444-445

Author(s):

Hugo E. Schwarz ◽

Hilmar W. Duerbeck ◽

Waltraut C. Seitter

Keyword(s):

High Resolution ◽

Southern Hemisphere ◽

Northern Hemisphere ◽

High Resolution Spectroscopy ◽

Symbiotic Stars ◽

Current Interest ◽

Echelle Spectrograph ◽

La Palma ◽

Recurrent Nova ◽

The Uk

A high resolution spectroscopy survey of symbiotic stars is conducted in the southern hemisphere by the authors, using the Coudé Echelle Spectrograph (CES), equipped with a CCD at the ESO Coudé Auxiliary Telescope (CAT), and concurrently in the northern hemisphere by Bode, Evans, Meaburn and collaborators, using the UK facilities at La Palma. So far, more than 400 spectra of about 70 stars have been obtained, mostly during 1988 and 1989. The southern part of the work will be described below.The discussion of symbiotic stars in the context of novae is not far-fetched. A number of symbiotics are known to have nova-like outbursts, and several novae are not easily distinguished from symbiotic stars. A noteworthy example is the most recently recognized recurrent nova, V745 Sco, first observed by Liller on July 24, 1989. It is described here, both because in late decline it represents a link between novae and symbiotic stars, and because of its current interest.

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Low Resolution Spectroscopy of 13 Low Surface Brightness PN's

Symposium - International Astronomical Union ◽

10.1017/s0074180900138331 ◽

1989 ◽

Vol 131 ◽

pp. 220-220

Author(s):

A. Manchado ◽

S. R. Pottasch ◽

A. Mampaso

Keyword(s):

Surface Brightness ◽

Photon Counting ◽

Outer Part ◽

Low Resolution ◽

Counting System ◽

Isaac Newton ◽

La Palma ◽

Ionization Structure ◽

Low Surface Brightness ◽

Isaac Newton Telescope

We have obtained long-slit low resolution spectra (7.5 A resolution) of a sample of 13 low surface brightness planetary nebulae using the 2.5-m Isaac Newton Telescope (La Palma) with the Image Photon Counting System (IPCS) covering a spectral range from 3300 A to 7300 A. From those spectra we calculated the ionic and total abundances of 0, N, Ne and Ar. Variations in the ionization structure between the inner and the outer part are found in some nebulae although the total abundances appear not to change significantly along the nebulae.

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Multiband Photometry of NGC 7479 and NGC 7606

International Astronomical Union Colloquium ◽

10.1017/s0252921100049605 ◽

1996 ◽

Vol 157 ◽

pp. 123-125

Author(s):

A. M. Varela ◽

J. A. L. Aguerri ◽

M. Prieto ◽

C. Muñoz-Tuñón

Keyword(s):

Spiral Galaxies ◽

Three Dimensional ◽

Surface Photometry ◽

Dimensional Model ◽

Three Dimensional Model ◽

Isaac Newton ◽

La Palma ◽

Radial Profiles ◽

Isaac Newton Telescope ◽

Barred Spiral Galaxies

We present surface photometry in U BV RI passbands of the barred spiral galaxies NGC 7479 and NGC 7606, for which observations were obtained at the Cassegrain focus of the 2.5-m Isaac Newton Telescope at La Palma. Data are presented in the form of images and mean radial profiles from azimuthal fits of ellipses, giving the luminosity, ellipticities and position angles of the isophotes as functions of the galactocentric radii. Images in I-band are shown in Figure 1 of NGC 7479 (left) and NGC 7606 (right). These belong to a sample of galaxies with moderate circumnuclear starbursts. We are analyzing their structure to study the effects of departures from an axisymmetric potential for the dynamics of a galaxy. One objective of this study is to make a three-dimensional model of the bar and bulge using the method of photometric inversion. The sample consists of 27 spiral galaxies with and without a bar.

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The Halos of NGC 6543 and NGC 6826

Symposium - International Astronomical Union ◽

10.1017/s0074180900138057 ◽

1989 ◽

Vol 131 ◽

pp. 196-196

Author(s):

A. Manchado ◽

S. R. Pottasch ◽

A. Mampaso

Keyword(s):

Photon Counting ◽

Central Zone ◽

Planetary Nebulae ◽

Low Resolution ◽

Electronic Temperature ◽

Counting System ◽

Isaac Newton ◽

Physical Conditions ◽

La Palma ◽

Isaac Newton Telescope

Long slit low resolution (3.4 A) spectra of the planetary nebulae NGC 6543 and NGC 6826, obtained using the 2.5-m Isaac Newton Telescope (La Palma) with the Image Photon Counting System (IPCS), indicate different physical conditions in the outer halos than in the central zone, with an outward increase of electronic temperature. The estimated mass contained in these halos is considerably larger than the values of the inner nebulae.

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Shock Modelling of the Bipolar Outflow Source NGC 6537

Symposium - International Astronomical Union ◽

10.1017/s0074180900171748 ◽

1993 ◽

Vol 155 ◽

pp. 385-385

Author(s):

L. Cuesta ◽

J. P. Phillips

Keyword(s):

High Resolution ◽

Narrow Band ◽

Type I ◽

High Excitation ◽

Optical Telescope ◽

Isaac Newton ◽

Bipolar Outflow ◽

La Palma ◽

Large Shell ◽

Isaac Newton Telescope

NGC 6537 is an unusual high excitation bipolar outflow source, with anomalous abundances indicative of a type I nebula. We have recently obtained a range of high resolution spectrophotometry for this source using the 2.5 m Isaac Newton Telescope (Observatorio del Roque de Los Muchachos, La Palma), together with narrow band optical imaging using the 2.6 m Nordic Optical Telescope (Observatorio del Roque de los Muchachos, La Palma). As a consequence, it is apparent that the source optical morphology is suggestive of the presence of an hyperbolic shock outflow surface, similar to those observed in other BPN (e.g. NGC 6302, Hb 5). Line ratio maps also indicate the presence of extremely strong [Nii] emission at the periphery of the outflow, whilst expansion velocities are of order ∼ 400 km sec−1. These large shell expansion velocities may in turn be driven by an extremely high velocity wind, which in this case appears to extend over a range ΔV ≥ 3000 km sec−1.

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Visual Extinction and Physical Conditions in the Bipolar Nebula M2-9

Symposium - International Astronomical Union ◽

10.1017/s0074180900171347 ◽

1993 ◽

Vol 155 ◽

pp. 345-345

Author(s):

A. Riera

Keyword(s):

Detailed Analysis ◽

Spectral Range ◽

Spectral Resolution ◽

Optical Spectra ◽

Isaac Newton ◽

Physical Conditions ◽

La Palma ◽

Visual Extinction ◽

Isaac Newton Telescope

A detailed analysis of the visual extinction and physical conditions of the extreme bipolar nebula M2-9 has been made from optical spectra acquired with the Intermediate Dispersion Spectrograph of the 2.5m Isaac Newton Telescope (Observatorio del Roque de los Muchachos, La Palma) in combination with a 235mm camera and the IPCS detector covering the spectral range 3500-7500 Å with spectral resolution of 4 Å.

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Galaxy Number-Counts to B = 28M

Symposium - International Astronomical Union ◽

10.1017/s0074180900048270 ◽

1994 ◽

Vol 161 ◽

pp. 645-648

Author(s):

N. Metcalfe ◽

T. Shanks ◽

N. Roche ◽

R. Fong

Keyword(s):

Power Law Distribution ◽

Isaac Newton ◽

La Palma ◽

The Galaxy ◽

History Of ◽

Isaac Newton Telescope ◽

William Herschel ◽

Ccd Detectors ◽

Number Counts ◽

Evolving Models

Counting the number of galaxies as a function of their apparent brightness is one of the fundamental cosmological tests, providing an important probe of both the geometry and evolutionary history of the Universe. CCD detectors have in recent years enabled astronomers to explore magnitude limits undreamed of a decade or so ago, and where important constraints can be placed on the allowable combinations of q 0 and evolution. Recent work has shown that the B-band counts keep rising with a power-law distribution, with a fivefold excess in the number of galaxies at B = 26.5 over that expected from simple non-evolving models. Indeed, it has been suggested that the total numbers of galaxies already seen may be too high for a q 0 = 0.5 universe, assuming there is a redshift cut-off in the galaxy distribution caused either by galaxies having strong Lyman limit systems or a low redshift of formation. As q 0 = 0.5 is favoured by theoretical arguments, it is important to see if the behaviour of the counts at even fainter magnitudes can be reconciled with a high density universe. Most published counts are unreliable faintward of B ≈ 26, as the incompleteness corrections required become comparable in size to the data. We have now extended the counts to B ∼ 28, using a ∼ 24 hour CCD exposure taken on the 2.5 m Isaac Newton telescope (INT) on La Palma, together with a ∼ 10 hour exposure on a small part of this field taken using the 4.2 m William Herschel Telescope (WHT).

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The Local Group census: IC-10

Symposium - International Astronomical Union ◽

10.1017/s0074180900212953 ◽

2003 ◽

Vol 212 ◽

pp. 581-582 ◽

Cited By ~ 1

Author(s):

Shelley A. Wright ◽

Robert Greimel ◽

Daniel J. Lennon ◽

Romano L.M. Corradi ◽

Nicholas A. Walton

Keyword(s):

Local Group ◽

Wide Field ◽

Irregular Galaxy ◽

Isaac Newton ◽

Luminous Blue Variables ◽

La Palma ◽

Ic 10 ◽

Magnitude Diagram ◽

Isaac Newton Telescope

We have begun a census of various stellar groups in Local Group Galaxies, using the wide field camera on the Isaac Newton Telescope on La Palma. Here we present a preliminary color-magnitude diagram for the dwarf irregular galaxy IC-10. At present time, metallicity of IC-10 is measured to be Z = 0.005 (Garnett 1990). Comparison with recent literature values of reddening and distance suggest that IC-10's distance is ~ 1 Mpc. Our comprehensive wide-field survey encompasses both broad (g′, r′, i′) and narrow-band (O iii, He ii, Hα, S ii, Strömgren y) observations to look for emission-line objects, including Wolf-Rayet stars and Luminous Blue Variables. The analysis also yields the coordinates of massive stars to an accuracy sufficient for follow-up multi-object spectroscopic observations.

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