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1. The Angular Diameter and Fundamental Parameters of Sirius A

Author

Davis, J., Ireland, M. J., North, J. R., Robertson, J. G., Tango, W. J., and Tuthill, P. G.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

The Sydney University Stellar Interferometer (SUSI) has been used to make a new determination of the angular diameter of Sirius A. The observations were made at an effective wavelength of 694.1 nm and the new value for the limb-darkened angular diameter is 6.048 +/- 0.040mas (+/-0.66%). This new result is compared with previous measurements and is found to be in excellent agreement with a conventionally calibrated measurement made with the European Southern Observatory's Very Large Telescope Interferometer (VLTI) at 2.176 microns (but not with a second globally calibrated VLTI measurement). A weighted mean of the SUSI and first VLTI results gives the limb-darkened angular diameter of Sirius A as 6.041 +/- 0.017mas (+/-0.28%). Combination with the Hipparcos parallax gives the radius equal to 1.713 +/- 0.009R_sun. The bolometric flux has been determined from published photometry and spectrophotometry and, combined with the angular diameter, yields the emergent flux at the stellar surface equal to (5.32+/- 0.14)x10^8 Wm^-2 and the effective temperature equal to 9845 +/- 64 K. The luminosity is 24.7 +/- 0.7 L_sun., Comment: Accepted for publication in PASA

Published
2010
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2. Interferometric Studies of Hot Stars at Sydney University

Author

Robertson, J. G., Davis, J., Ireland, M. J., Tuthill, P. G., Tango, W. J., Jacob, A. P., North, J. R., and Brummelaar, T. A. ten

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

The University of Sydney has a long history in optical stellar interferometry. The first project, in the 1960s, was the Narrabri Stellar Intensity Interferometer, which measured the angular diameters of 32 hot stars and established the temperature scale for spectral classes O - F. That instrument was followed by the Sydney University Stellar Interferometer (SUSI), which is now undergoing a third-generation upgrade, to use the multi-wavelength PAVO beam combiner. SUSI operates at visible rather than IR wavelengths and has baselines up to 160 m, so it is well suited to the study of hot stars. A number of studies have been carried out, and more are planned when commissioning of the PAVO system is complete. Conversion of the system to allow remote operation will allow larger scientific projects to be undertaken., Comment: 2 pages. To appear in RevMexAA(SC) 'The Interferometric View on Hot Stars' (Conference held at Vina del Mar, March 2-6, 2009)

Published
2009

3. Observations of the pulsation of the Cepheid l Car with the Sydney University Stellar Interferometer

Author

Davis, J., Jacob, A. P., Robertson, J. G., Ireland, M. J., North, J. R., Tango, W. J., and Tuthill, P. G.

Subjects
Astrophysics
Abstract

Observations of the southern Cepheid l Car to yield the mean angular diameter and angular pulsation amplitude have been made with the Sydney University Stellar Interferometer (SUSI) at a wavelength of 696 nm. The resulting mean limb-darkened angular diameter is 2.990+-0.017 mas (i.e. +-0.6 per cent) with a maximum-to-minimum amplitude of 0.560+-0.018 mas corresponding to 18.7+-0.6 per cent in the mean stellar diameter. Careful attention has been paid to uncertainties, including those in measurements, in the adopted calibrator angular diameters, in the projected values of visibility squared at zero baseline, and to systematic effects. No evidence was found for a circumstellar envelope at 696 nm. The interferometric results have been combined with radial displacements of the stellar atmosphere derived from selected radial velocity data taken from the literature to determine the distance and mean diameter of l Car. The distance is determined to be 525+-26 pc and the mean radius 169+-8R{solar). Comparison with published values for the distance and mean radius show excellent agreement, particularly when a common scaling factor from observed radial velocity to pulsation velocity of the stellar atmosphere (the p-factor) is used., Comment: 12 pages, 5 figures, accepted by MNRAS

Published
2008
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4. A new determination of the orbit and masses of the Be binary system delta Scorpii

Author

Tango, W. J., Davis, J., Jacob, A. P., Mendez, A., North, J. R., O'Byrne, J. W., Seneta, E. B., and Tuthill, P. G.

Subjects
Astrophysics
Abstract

The binary star delta Sco (HD143275) underwent remarkable brightening in the visible in 2000, and continues to be irregularly variable. The system was observed with the Sydney University Stellar Interferometer (SUSI) in 1999, 2000, 2001, 2006 and 2007. The 1999 observations were consistent with predictions based on the previously published orbital elements. The subsequent observations can only be explained by assuming that an optically bright emission region with an angular size of > 2 +/- 1 mas formed around the primary in 2000. By 2006/2007 the size of this region grew to an estimated > 4 mas. We have determined a consistent set of orbital elements by simultaneously fitting all the published interferometric and spectroscopic data as well as the SUSI data reported here. The resulting elements and the brightness ratio for the system measured prior to the outburst in 2000 have been used to estimate the masses of the components. We find Ma = 15 +/- 7 Msun and Mb = 8.0 +/- 3.6 Msun. The dynamical parallax is estimated to be 7.03 +/- 0.15 mas, which is in good agreement with the revised HIPPARCOS parallax., Comment: 8 pages, 4 figs. Accepted for publication in MNRAS

Published
2008
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5. The radius and other fundamental parameters of the F9 V star beta Virginis

Author

North, J. R., Davis, J., Robertson, J. G., Bedding, T. R., Bruntt, H., Ireland, M. J., Jacob, A. P., Lacour, S., O'Byrne, J. W., Owens, S. M., Stello, D., Tango, W. J., and Tuthill, P. G.

Subjects
Astrophysics
Abstract

We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of the F9 V star beta Virginis. After correcting for limb darkening and combining with the revised Hipparcos parallax, we derive a radius of 1.703 +/- 0.022 R_sun (1.3%). We have also calculated the bolometric flux from published measurements which, combined with the angular diameter, implies an effective temperature of 6059 +/- 49 K (0.8%). We also derived the luminosity of beta Vir to be L = 3.51 +/- 0.08 L_sun (2.1%). Solar-like oscillations were measured in this star by Carrier et al. (2005) and using their value for the large frequency separation yields the mean stellar density with an uncertainty of about 2%. Our constraints on the fundamental parameters of beta Vir will be important to test theoretical models of this star and its oscillations., Comment: accepted for publication in MNRAS. Updated references

Published
2008
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6. The fundamental parameters of the roAp star alpha Circini

Author

Bruntt, H., North, J. R., Cunha, M., Brandao, I. M., Elkin, V. G., Kurtz, D. W., Davis, J., Bedding, T. R., Jacob, A. P., Owens, S. M., Robertson, J. G., Tango, W. J., Gameiro, J. F., Ireland, M. J., and Tuthill, P. G.

Subjects
Astrophysics
Abstract

We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of alpha Cir. This is the first detailed interferometric study of a rapidly oscillating A (roAp) star, alpha Cir being the brightest member of its class. We used the new and more accurate Hipparcos parallax to determine the radius to be 1.967+-0.066 Rs. We have constrained the bolometric flux from calibrated spectra to determine an effective temperature of 7420+-170 K. This is the first direct determination of the temperature of an roAp star. Our temperature is at the low end of previous estimates, which span over 1000 K and were based on either photometric indices or spectroscopic methods. In addition, we have analysed two high-quality spectra of alpha Cir, obtained at different rotational phases and we find evidence for the presence of spots. In both spectra we find nearly solar abundances of C, O, Si, Ca and Fe, high abundance of Cr and Mn, while Co, Y, Nd and Eu are overabundant by about 1 dex. The results reported here provide important observational constraints for future studies of the atmospheric structure and pulsation of alpha Cir., Comment: Accepted by MNRAS (9 pages, 3 figures, 6 tables)

Published
2008
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7. The Emergent Flux and Effective Temperature of Delta Canis Majoris

Author

Davis, J., Booth, A. J., Ireland, M. J., Jacob, A. P., North, J. R., Owens, S. M., Robertson, J. G., Tango, W. J., and Tuthill, P. G.

Subjects
Astrophysics
Abstract

New angular diameter determinations for the bright southern F8 supergiant Delta CMa enable the bolometric emergent flux and effective temperature of the star to be determined with improved accuracy. The spectral flux distribution and bolometric flux have been determined from published photometry and spectrophotometry and combined with the angular diameter to derive the bolometric emergent flux F = (6.50 plus/minus 0.24) x 10^7 W/m^2 and the effective temperature Teff = 5818 plus/minus 53 K. The new value for the effective temperature is compared with previous interferometric and infrared flux method determinations. The accuracy of the effective temperature is now limited by the uncertainty in the bolometric flux rather than by the uncertainty in the angular diameter., Comment: 8 pages, 4 figures

Published
2007
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8. The Sydney University Stellar Interferometer: A Major Upgrade to Spectral Coverage and Performance

Author

Davis, J., Ireland, M. J., Chow, J., Jacob, A. P., Lucas, R. E., North, J. R., O'Byrne, J. W., Owens, S. M., Robertson, J. G., Seneta, E., Tango, W. J., and Tuthill, P. G.

Subjects
Astrophysics
Abstract

A new beam-combination and detection system has been installed in the Sydney University Stellar Interferometer working at the red end of the visual spectrum (wavelength range 500-950 nm) to complement the existing blue-sensitive system (wavelength range 430-520 nm) and to provide an increase in sensitivity. Dichroic beam-splitters have been introduced to allow simultaneous observations with both spectral system, albeit with some restriction on the spectral range of the longer wavelength system (wavelength range 550-760 nm). The blue system has been upgraded to allow remote selection of wavelength and spectral bandpass, and to enable simultaneous operation with the red system with the latter providing fringe-envelope tracking. The new system and upgrades are described and examples of commissioning tests presented. As an illustration of the improvement in performance the measurement of the angular diameter of the southern F supergiant delta CMa is described and compared with previous determinations., Comment: 13 pages, 14 figures

Published
2007
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9. Orbital Solution & Fundamental Parameters of sigma Scorpii

Author

North, J. R., Davis, J., Tuthill, P. G., Tango, W. J., and Robertson, J. G.

Subjects
Astrophysics
Abstract

The first orbital solution for the spectroscopic pair in the multiple star system sigma Scorpii, determined from measurements with the Sydney University Stellar Interferometer (SUSI), is presented. The primary component is of beta Cephei variable type and has been one of the most intensively studied examples of its class. The orbital solution, when combined with radial velocity results found in the literature, yields a distance of 174(+23,-18) pc, which is consistent with, but more accurate than the Hipparcos value. For the primary component we determine 18.4+/-5.4 M_sun, -4.12+/-0.34 mag and 12.7+/-1.8 R_sun for the mass, absolute visual magnitude and radius respectively. A B1 dwarf spectral type and luminosity class for the secondary is proposed from the mass determination of 11.9+/-3.1 M_sun and the estimated system age of 10 Myr., Comment: 4 figures, 5 tables, to appear in MNRAS

Published
2007
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10. The radius and mass of the subgiant star bet Hyi from interferometry and asteroseismology

Author

North, J. R., Davis, J., Bedding, T. R., Ireland, M. J., Jacob, A. P., O'Byrne, J., Owens, S. M., Robertson, J. G., Tango, W. J., and Tuthill, P. G.

Subjects
Astrophysics
Abstract

We have used the Sydney University Stellar Interferometer (SUSI) to measure the angular diameter of beta Hydri. This star is a nearby G2 subgiant whose mean density was recently measured with high precision using asteroseismology. We determine the radius and effective temperature of the star to be 1.814+/-0.017 R_sun (0.9%) and 5872+/-44 K (0.7%) respectively. By combining this value with the mean density, as estimated from asteroseismology, we make a direct estimate of the stellar mass. We find a value of 1.07+/-0.03 M_sun (2.8%), which agrees with published estimates based on fitting in the H-R diagram, but has much higher precision. These results place valuable constraints on theoretical models of beta Hyi and its oscillation frequencies., Comment: 3 figures, 3 tables, to appear in MNRAS Letters

Published
2007
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11. \gamma^2 Velorum: Orbital Solution and Fundamental Parameter Determination with SUSI

Author

North, J. R., Tuthill, P. G., Tango, W. J., and Davis, J.

Subjects
Astrophysics
Abstract

The first complete orbital solution for the double-lined spectroscopic binary system \gamma^2 Velorum, obtained from measurements with the Sydney University Stellar Interferometer (SUSI), is presented. This system contains the closest example of a Wolf-Rayet star and the promise of full characterisation of the basic properties of this exotic high-mass system has subjected it to intense study as an archetype for its class. In combination with the latest radial-velocity results, our orbital solution produces a distance of 336^{+8}_{-7} pc, significantly more distant than the Hipparcos estimation (Schaerer et al. 1997; van der Hucht 1997). The ability to fully specify the orbital parameters has enabled us to significantly reduce uncertainties and our result is consistent with the VLTI observational point (Millour et al. 2006), but not with their derived distance. Our new distance, which is an order of magnitude more precise than prior work, demands critical reassessment of all distance-dependent fundamental parameters of this important system. In particular, membership of the Vela OB2 association has been reestablished, and the age and distance are also in good accord with the population of young stars reported by Pozzo et al. (2000). We determine the O-star primary component parameters to be M_V(O) = -5.63 \pm 0.10 mag, R(O) = 17 \pm 2 R_{\sun} and {\cal M}(O) = 28.5 \pm 1.1 M_{\sun}. These values are consistent with calibrations found in the literature if a luminosity class of II--III is adopted. The parameters of the Wolf-Rayet component are M_v(WR) = -4.33 \pm 0.17 mag and {\cal M}(WR) = 9.0 \pm 0.6 M_{\sun}., Comment: 3 figures, accepted for publication in MNRAS

Published
2007
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12. Orbital elements, masses and distance of lambda Scorpii A and B determined with the Sydney University Stellar Interferometer and high resolution spectroscopy

Author

Tango, W. J., Davis, J., Ireland, M. J., Aerts, C., Uytterhoeven, K., Jacob, A. P., Mendez, A., North, J. R., Seneta, E. B., and Tuthill, P. G.

Subjects
Astrophysics
Abstract

The triple system HD158926 (lambda Sco) has been observed interferometrically with the Sydney University Stellar Interferometer and the elements of the wide orbit have been determined. These are significantly more accurate than the previous elements found spectroscopically. The inclination of the wide orbit is consistent with the inclination previously found for the orbit of the close companion. The wide orbit also has low eccentricity, suggesting that the three stars were formed at the same time. The brightness ratio between the two B stars was also measured at lambda = 442nm and 700nm. The brightness ratio and colour index are consistent with the previous classification of lambda Sco A as B1.5 and lambda Sco B as B2. Evolutionary models show that the two stars lie on the main sequence. Since they have have the same age and luminosity class (IV) the mass-luminosity relation can be used to determine the mass ratio of the two stars: M_B/M_A = 0.76+/-0.04. The spectroscopic data have been reanalyzed using the interferometric values for P, T, e and omega, leading to revised values for a_1sin i and the mass function. The individual masses can be found from the mass ratio, the mass function, spectrum synthesis and the requirement that the age of both components must be the same: M_A = 10.4+/-1.3 Msun and M_B = 8.1+/-1.0 Msun. The masses, angular semimajor axis and the period of the system can be used to determine the dynamical parallax. We find the distance to lambda Sco to be 112+/-5 pc, which is approximately a factor of two closer than the HIPPARCOS value of 216+/-42 pc., Comment: 8 pages, 4 figures. Accepted for publication by Monthly Notices of the Royal Astronomical Society

Published
2006
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15. ��^2 Velorum: Orbital Solution and Fundamental Parameter Determination with SUSI

Author

North, J. R., Tuthill, P. G., Tango, W. J., and Davis, J.

Subjects
Astrophysics (astro-ph), FOS: Physical sciences
Abstract

The first complete orbital solution for the double-lined spectroscopic binary system ��^2 Velorum, obtained from measurements with the Sydney University Stellar Interferometer (SUSI), is presented. This system contains the closest example of a Wolf-Rayet star and the promise of full characterisation of the basic properties of this exotic high-mass system has subjected it to intense study as an archetype for its class. In combination with the latest radial-velocity results, our orbital solution produces a distance of 336^{+8}_{-7} pc, significantly more distant than the Hipparcos estimation (Schaerer et al. 1997; van der Hucht 1997). The ability to fully specify the orbital parameters has enabled us to significantly reduce uncertainties and our result is consistent with the VLTI observational point (Millour et al. 2006), but not with their derived distance. Our new distance, which is an order of magnitude more precise than prior work, demands critical reassessment of all distance-dependent fundamental parameters of this important system. In particular, membership of the Vela OB2 association has been reestablished, and the age and distance are also in good accord with the population of young stars reported by Pozzo et al. (2000). We determine the O-star primary component parameters to be M_V(O) = -5.63 \pm 0.10 mag, R(O) = 17 \pm 2 R_{\sun} and {\cal M}(O) = 28.5 \pm 1.1 M_{\sun}. These values are consistent with calibrations found in the literature if a luminosity class of II--III is adopted. The parameters of the Wolf-Rayet component are M_v(WR) = -4.33 \pm 0.17 mag and {\cal M}(WR) = 9.0 \pm 0.6 M_{\sun}., 3 figures, accepted for publication in MNRAS

Published
2007
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17. The angular diameter and fundamental parameters of Sirius A

Author

Davis, J, North, J R, Robertson, James G, Tango, W J, Tuthill, Peter G, Ireland, Michael, Davis, J, North, J R, Robertson, James G, Tango, W J, Tuthill, Peter G, and Ireland, Michael

Abstract

The Sydney University Stellar Interferometer (SUSI) has been used to make a new determination of the angular diameter of Sirius A. The observations were made at an effective wavelength of 694.1nm and the new value for the limb-darkened angular diameter is 6.048 ± 0.040 mas (±0.66%). This new result is compared with previous measurements and is found to be in excellent agreement with a conventionally calibrated measurement made with the European Southern Observatory's Very Large Telescope Interferometer (VLTI) at 2.176m (but not with a second globally calibrated VLTI measurement). A weighted mean of the SUSI and first VLTI results gives the limb-darkened angular diameter of Sirius A as 6.041±0.017mas (±0.28%). Combination with the Hipparcos parallax gives the radius equal to 1.7130.009R⊙. The bolometric flux has been determined from published photometry and spectrophotometry and, combined with the angular diameter, yields the emergent flux at the stellar surface equal to (5.32±0.14) × 108Wm-2 and the effective temperature equal to 9845±64K. The luminosity is 24.7±0.7L⊙.

Published
2011

18. Observations of the pulsation of the Cepheid l Car with the Sydney University Stellar Interferometer

Author

Davis, J, Jacob, A P, Robertson, James G, North, J R, Tango, W J, Tuthill, Peter G, Ireland, Michael, Davis, J, Jacob, A P, Robertson, James G, North, J R, Tango, W J, Tuthill, Peter G, and Ireland, Michael

Abstract

Observations of the southern Cepheid ℓ Car to yield the mean angular diameter and angular pulsation amplitude have been made with the Sydney University Stellar Interferometer at a wavelength of 696 nm. The resulting mean limb-darkened angular diameter i

Published
2009

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Author

Bruntt, H., North, J. R., Cunha, M., Brandão, I. M., Elkin, V. G., Kurtz, D. W., Davis, J., Bedding, T. R., Jacob, A. P., Owens, S. M., Robertson, J. G., Tango, W. J., Gameiro, J. F., Ireland, M. J., Tuthill, P. G., Bruntt, H., North, J. R., Cunha, M., Brandão, I. M., Elkin, V. G., Kurtz, D. W., Davis, J., Bedding, T. R., Jacob, A. P., Owens, S. M., Robertson, J. G., Tango, W. J., Gameiro, J. F., Ireland, M. J., and Tuthill, P. G.

Published
2008

20. This title is unavailable for guests, please login to see more information.

Author

Bruntt, H., North, J. R., Cunha, M., Brandão, I. M., Elkin, V. G., Kurtz, D. W., Davis, J., Bedding, T. R., Jacob, A. P., Owens, S. M., Robertson, J. G., Tango, W. J., Gameiro, J. F., Ireland, M. J., Tuthill, P. G., Bruntt, H., North, J. R., Cunha, M., Brandão, I. M., Elkin, V. G., Kurtz, D. W., Davis, J., Bedding, T. R., Jacob, A. P., Owens, S. M., Robertson, J. G., Tango, W. J., Gameiro, J. F., Ireland, M. J., and Tuthill, P. G.

Published
2008

24. The radius and other fundamental parameters of the F9 V star β Virginis

Author

North, J. R., primary, Davis, J., additional, Robertson, J. G., additional, Bedding, T. R., additional, Bruntt, H., additional, Ireland, M. J., additional, Jacob, A. P., additional, Lacour, S., additional, O'Byrne, J. W., additional, Owens, S. M., additional, Stello, D., additional, Tango, W. J., additional, and Tuthill, P. G., additional

Published
2009
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25. The fundamental parameters of the roAp star α Circini

Author

Bruntt, H., primary, North, J. R., additional, Cunha, M., additional, Brandão, I. M., additional, Elkin, V. G., additional, Kurtz, D. W., additional, Davis, J., additional, Bedding, T. R., additional, Jacob, A. P., additional, Owens, S. M., additional, Robertson, J. G., additional, Tango, W. J., additional, Gameiro, J. F., additional, Ireland, M. J., additional, and Tuthill, P. G., additional

Published
2008
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32. Poster Abstracts

Author

Littger, Ralf, primary, Alke, Alexandra, additional, Tewes, Bernhard, additional, Gropp, Felix, additional, Asai, T., additional, Watanabe, K., additional, Kuromi, K., additional, Kurohane, K., additional, Ogino, K., additional, Taki, T., additional, Tsukada, H., additional, Nakayama, J., additional, Oku, N., additional, Babai, I., additional, Matyas, G., additional, Baranji, L., additional, Milosevits, J., additional, Alving, C. R., additional, Bendas, G., additional, Rothe, U., additional, Scherphof, G. L., additional, Kamps, J. A. A. M., additional, Kessner, S., additional, Carafa, M., additional, Di Stefano, A., additional, Sozio, P., additional, Cacciatore, I., additional, Mosciatti, B., additional, Santucci, E., additional, Choice, E., additional, Harvie, P., additional, Galbraith, T., additional, Zunder, E., additional, Dutzar, B., additional, Anklesaria, P., additional, Paul, R., additional, Cocquyt, J., additional, De Cuyper, M., additional, Van der Meeren, P., additional, Cruz, M. E. M., additional, Gaspar, M. M., additional, Silva, M. T., additional, Dathe, M., additional, Nikolenko, H., additional, Wessolowski, A., additional, Schmieder, P., additional, Beyermann, M., additional, Bienert, M., additional, Santos, N. Dos, additional, Cox, K. A., additional, Allen, C., additional, Gallagher, R. C., additional, Ickenstein, L., additional, Mayer, L. D., additional, Bally, M. B., additional, Fischer, S., additional, Margalit, R., additional, Freisleben, H.-J., additional, Garidel, P., additional, Chen, H. C., additional, Moore, D., additional, Mendelsohn, R., additional, Keller, M., additional, Hildebrand, A., additional, Blume, A., additional, Girão da Cruz, M. T., additional, Simões, S., additional, Pedroso de Lima, M. C., additional, Graser, A., additional, Nahde, T., additional, Fahr, A., additional, Müller, R., additional, Müller-Brüsselbach, S., additional, Cudmore, S., additional, O'Mahony, D., additional, Hoving, S., additional, van Tiel, S. T., additional, Seynhaeve, A. L. B., additional, Ambagtsheer, G., additional, Eggermont, A. M. M., additional, ten Hagen, T. L. M., additional, Høyrup, P., additional, Jensen, S. S., additional, Jørgensen, K., additional, Iden, D., additional, Kuang, H., additional, Mullen, P., additional, Jacobs, C., additional, Roben, P., additional, Stevens, T., additional, Lollo, C., additional, Ishida, T., additional, Maeda, R., additional, Masuda, K., additional, Ichihara, M., additional, Kiwada, H., additional, Jung, K., additional, Reszka, R., additional, Kaiser, N., additional, Ohloff, I., additional, Linser-Haar, S., additional, Massing, U., additional, Schubert, R., additional, Kan, P., additional, Tsao, C. W., additional, Chen, W. K., additional, Wang, A. J., additional, Kimpfler, A., additional, Gerber, C., additional, Wieschollek, A., additional, Bruchelt, G., additional, Kobayashi, T., additional, Okada, Y., additional, Sone, S., additional, Harashima, H., additional, Maruyama, K., additional, Kondo, Masayo, additional, Lee, Chun Man, additional, Tanaka, Toshiyuki, additional, Su, Wei, additional, Kitagawa, Toru, additional, Ito, Toshinori, additional, Matsuda, Hikaru, additional, Murai, Toshiyuki, additional, Miyasaka, Masayuki, additional, Junji, Kimura, additional, Kondo, Masami, additional, Asai, Tomohiro, additional, Ogino, Koichi, additional, Taki, Takao, additional, Tsukada, Hideo, additional, Baba, Kazuhiko, additional, Oku, Naoto, additional, Koning, G. A., additional, Wauben, M. H. M., additional, Vestweber, D., additional, Everts, M., additional, Kok, R. J., additional, Schraa, A. J., additional, Molema, G., additional, Schiffelers, R. M., additional, Storm, G., additional, Kristl, J., additional, Šentjurc, M., additional, Abramović, Z., additional, Landry, S., additional, Perron, S., additional, Bestman-Smith, J., additional, Désormeaux, A., additional, Tremblay, M. J., additional, Bergeron, M. G., additional, Madeira, C., additional, Loura, L. M. S., additional, Fedorov, A., additional, Prieto, M., additional, Aires-Barros, M. R., additional, Marques, C. M., additional, Simões, S. I., additional, Cruz, M. E., additional, Cevc, G., additional, Martins, M. B., additional, Moreira, J. N., additional, Gaspar, R., additional, Allen, T. M., additional, Esposito, C., additional, Ortaggi, G., additional, Bianco, A., additional, Bonadies, F., additional, Malizia, D., additional, Napolitano, R., additional, Cametti, C., additional, Mossa, G., additional, Endert, Gerold, additional, Essler, Frank, additional, Lutz, Silke, additional, Panzner, Steffen, additional, Pastorino, F., additional, Brignole, C., additional, Pagnan, G., additional, Moase, E. H., additional, Ponzoni, M., additional, Pavelic, Z., additional, Škalko-Basnet, N., additional, Jalšenjak, I., additional, Penacho, N., additional, Pisano, C., additional, Bucci, F., additional, Serafini, S., additional, Martinelli, R., additional, Cupelli, A., additional, Marconi, A., additional, Ferrara, F. F., additional, Santaniello, M., additional, Critelli, L., additional, Tinti, O., additional, Luisi, P., additional, Carminati, P., additional, Galletti, B., additional, Sauer, I., additional, Schleef, M., additional, Voß, C., additional, Schmidt, T., additional, Flaschel, E., additional, König, S., additional, Wenger, T., additional, Dumond, J., additional, Bogetto, N., additional, Reboud-Ravaux, M., additional, Schramm, H. J., additional, Schramm, W., additional, Sheynis, T., additional, Rozner, S., additional, Kolusheva, S., additional, Satchell, D., additional, Jelnik, R., additional, Shigeta, Y., additional, Imanaka, H., additional, Ando, H., additional, Makino, T., additional, Baba, N., additional, Shimizu, K., additional, Takada, M., additional, Baba, K., additional, Namba, Y., additional, Simberg, Dmitri, additional, Danino, Dganit, additional, Talmon, Yeshayahu, additional, Minsky, Abraham, additional, Ferrari, Marilyn E., additional, Wheeler, Carl J., additional, Barenholz, Yechezkel, additional, Takada, Miki, additional, Shimizu, Kosuke, additional, Kuromi, Koici, additional, Takeuchi, Y., additional, North, J. R., additional, Nango, M., additional, Tewes, B., additional, Köchling, T., additional, Deissler, M., additional, Kühl, C., additional, Marx, U., additional, Strote, G., additional, Gropp, F., additional, Qualls, Marquita M., additional, Kim, Jong-Mok, additional, Thompson, David H., additional, Zhang, Zhi-Yi, additional, Shum, Pochi, additional, Collier, Joel H., additional, Hu, Bi-Huang, additional, Ruberti, Jeffrey W., additional, Messersmith, Phillip B., additional, Tsuruda, T., additional, Nakade, A., additional, Sadzuka, Y., additional, Hirota, S., additional, Sonobe, T., additional, Vorauer-Uhl, K., additional, Wagner, A., additional, Katinger, H., additional, Weeke-Klimp, A. H., additional, Bartsch, M., additional, Meijer, D. K. F., additional, Zeisig, R., additional, Walther, W., additional, Reß, A., additional, Fichtner, I., additional, Zschörnig, O., additional, Schiller, J., additional, Süß, M., additional, Bergmeier, C., additional, Arnold, K., additional, Nchinda, Godwin, additional, Überla, Klaus, additional, and Zschörnig, Olaf, additional

Published
2003
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33. Cepheid Observations with the Sydney University Stellar Interferometer: ℓCarinae and βDoradus.

Author

Leibundgut, Bruno, Richichi, A., Delplancke, F., Paresce, F., Chelli, A., Davis, J., Ireland, M. J., Jacob, A. P., North, J. R., Owens, S. M., Robertson, J. G., Tango, W. J., and Tuthill, P. G.

Abstract

Observations of the southern Cepheids ℓCar and β Dor to yield the mean angular diameters and angular pulsation amplitudes have been made with the Sydney University Stellar Interferometer (SUSI)at a wavelength of 700 nm. The results of a preliminary analysis are compared with those obtained with the VLTI at 2.2 μm and excellent agreement between the results from the two instruments is found for ℓCar but there are significant differences for βDor. [ABSTRACT FROM AUTHOR]

Published
2008
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34. γ2 Velorum: orbital solution and fundamental parameter determination with SUSI.

Author

North, J. R., Tuthill, P. G., Tango, W. J., and Davis, J.

Subjects
BINARY stars, SPECTROSCOPIC imaging, DIAGNOSTIC imaging, WOLF-Rayet stars, EARLY stars
Abstract

The first complete orbital solution for the double-lined spectroscopic binary system γ2 Velorum, obtained from measurements with the Sydney University Stellar Interferometer (SUSI), is presented. This system contains the closest example of a Wolf–Rayet star and the promise of full characterization of the basic properties of this exotic high-mass system has subjected it to intense study as an archetype for its class. In combination with the latest radial-velocity results, our orbital solution produces a distance of , significantly more distant than the Hipparcos estimation. The ability to fully specify the orbital parameters has enabled us to significantly reduce uncertainties and our result is consistent with the Very Large Telescope Interferometer (VLTI) observational point, but not with their derived distance. Our new distance, which is an order of magnitude more precise than prior work, demands critical reassessment of all distance-dependent fundamental parameters of this important system. In particular, membership of the Vela OB2 association has been re-established, and the age and distance are also in good accord with the population of young stars reported by Pozzo et al. We determine the O-star primary component parameters to be and . These values are consistent with calibrations found in the literature if a luminosity class of II–III is adopted. The parameters of the Wolf–Rayet (WR) component are M v(WR) =−4.33 ± 0.17 mag and . [ABSTRACT FROM AUTHOR]

Published
2007
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35. Orbital elements, masses and distance of λ Scorpii A and B determined with the Sydney University Stellar Interferometer and high-resolution spectroscopy.

Author

Tango, W. J., Davis, J., Ireland, M. J., Aerts, C., Uytterhoeven, K., Jacob, A. P., Mendez, A., North, J. R., Seneta, E. B., and Tuthill, P. G.

Subjects
ORBITS (Astronomy), SPECTRUM analysis, ASTRONOMICAL photometry, STELLAR mass, PARALLAX, ASTROPHYSICS
Abstract

The triple system HD 158926 (λ Sco) has been observed interferometrically with the Sydney University Stellar Interferometer, and the elements of the wide orbit have been determined. These are significantly more accurate than the previous elements found spectroscopically. The inclination of the wide orbit is consistent with the inclination previously found for the orbit of the close companion. The wide orbit also has low eccentricity, suggesting that the three stars were formed at the same time. The brightness ratio between the two B stars was also measured at and 700 nm. The brightness ratio and colour index are consistent with the previous classification of λ Sco A as B1.5 and λ Sco B as B2. Evolutionary models show that the two stars lie on the main sequence. Since they have the same age and luminosity class (IV), the mass–luminosity relation can be used to determine the mass ratio of the two stars: . The spectroscopic data have been reanalyzed using the interferometric values for P, T, e and ω, leading to revised values for and the mass function. The individual masses can be found from the mass ratio, the mass function, spectrum synthesis and the requirement that the age of both components must be the same: and . The masses, angular semimajor axis and the period of the system can be used to determine the dynamical parallax. We find the distance to λ Sco to be , which is approximately a factor of 2 closer than the Hipparcos value of . [ABSTRACT FROM AUTHOR]

Published
2006
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48. Purified Epstein-Barr virus Mr 340,000 glycoprotein induces potent virus-neutralizing antibodies when incorporated in liposomes.

Author

North, J R, Morgan, A J, Thompson, J L, and Epstein, M A

Abstract

The purified Mr 340,000 glycoprotein component of Epstein-Barr (EB) virus-induced membrane antigen complex incorporated into liposomes was shown to be a potent immunogen in mice. High-titer antisera were induced that (i) are specific for membrane antigen components without absorption, (ii) bind the antigens induced by three different EB virus isolates, and (iii) neutralize the ability of the virus to transform fetal cord blood lymphocytes in vitro. The development of this immunogenic form of purified antigen provides an important step towards a potential subunit vaccine against Epstein-Barr virus infection.

Published
1982
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49. Poster Abstracts

Author

Littger, Ralf, Alke, Alexandra, Tewes, Bernhard, Gropp, Felix, Asai, T., Watanabe, K., Kuromi, K., Kurohane, K., Ogino, K., Taki, T., Tsukada, H., Nakayama, J., Oku, N., Babai, I., Matyas, G., Baranji, L., Milosevits, J., Alving, C. R., Bendas, G., Rothe, U., Scherphof, G. L., Kamps, J. A. A. M., Kessner, S., Rothe, U., Bendas, G., Carafa, M., Di Stefano, A., Sozio, P., Cacciatore, I., Mosciatti, B., Santucci, E., Choice, E., Harvie, P., Galbraith, T., Zunder, E., Dutzar, B., Anklesaria, P., Paul, R., Cocquyt, J., De Cuyper, M., Van der Meeren, P., Cruz, M. E. M., Gaspar, M. M., Silva, M. T., Dathe, M., Nikolenko, H., Wessolowski, A., Schmieder, P., Beyermann, M., Bienert, M., Santos, N. Dos, Cox, K. A., Allen, C., Gallagher, R. C., Ickenstein, L., Mayer, L. D., Bally, M. B., Fischer, S., Margalit, R., Freisleben, H.-J., Garidel, P., Chen, H. C., Moore, D., Mendelsohn, R., Garidel, P., Keller, M., Hildebrand, A., Blume, A., Girão da Cruz, M. T., Simões, S., Pedroso de Lima, M. C., Graser, A., Nahde, T., Fahr, A., Müller, R., Müller-Brüsselbach, S., Harvie, P., Dutzar, B., Choice, E., Cudmore, S., O'Mahony, D., Anklesaria, P., Paul, R., Hoving, S., van Tiel, S. T., Seynhaeve, A. L. B., Ambagtsheer, G., Eggermont, A. M. M., ten Hagen, T. L. M., Høyrup, P., Jensen, S. S., Jørgensen, K., Iden, D., Kuang, H., Mullen, P., Jacobs, C., Roben, P., Stevens, T., Lollo, C., Ishida, T., Maeda, R., Masuda, K., Ichihara, M., Kiwada, H., Jung, K., Reszka, R., Kaiser, N., Ohloff, I., Linser-Haar, S., Massing, U., Schubert, R., Kan, P., Tsao, C. W., Chen, W. K., Wang, A. J., Kimpfler, A., Gerber, C., Wieschollek, A., Bruchelt, G., Schubert, R., Kobayashi, T., Okada, Y., Ishida, T., Sone, S., Harashima, H., Maruyama, K., Kiwada, H., Kondo, Masayo, Lee, Chun Man, Tanaka, Toshiyuki, Su, Wei, Kitagawa, Toru, Ito, Toshinori, Matsuda, Hikaru, Murai, Toshiyuki, Miyasaka, Masayuki, Junji, Kimura, Kondo, Masami, Asai, Tomohiro, Ogino, Koichi, Taki, Takao, Tsukada, Hideo, Baba, Kazuhiko, Oku, Naoto, Koning, G. A., Wauben, M. H. M., ten Hagen, T. L. M., Vestweber, D., Everts, M., Kok, R. J., Schraa, A. J., Molema, G., Schiffelers, R. M., Storm, G., Kristl, J., Šentjurc, M., Abramovi, Z., Landry, S., Perron, S., Bestman-Smith, J., Désormeaux, A., Tremblay, M. J., Bergeron, M. G., Madeira, C., Loura, L. M. S., Fedorov, A., Prieto, M., Aires-Barros, M. R., Marques, C. M., Simões, S. I., Cruz, M. E., Cevc, G., Martins, M. B., Moreira, J. N., Gaspar, R., Allen, T. M., Esposito, C., Ortaggi, G., Bianco, A., Bonadies, F., Malizia, D., Napolitano, R., Cametti, C., Mossa, G., Endert, Gerold, Essler, Frank, Lutz, Silke, Panzner, Steffen, Pastorino, F., Brignole, C., Pagnan, G., Moase, E. H., Allen, T. M., Ponzoni, M., Pavelic, Z., Škalko-Basnet, N., Jalšenjak, I., Penacho, N., Simões, S., Pedroso de Lima, M. C., Pisano, C., Bucci, F., Serafini, S., Martinelli, R., Cupelli, A., Marconi, A., Ferrara, F. F., Santaniello, M., Critelli, L., Tinti, O., Luisi, P., Carminati, P., Santaniello, M., Bucci, F., Tinti, O., Pisano, C., Critelli, L., Galletti, B., Luisi, P., Carminati, P., Sauer, I., Nikolenko, H., Dathe, M., Schleef, M., Voß, C., Schmidt, T., Flaschel, E., König, S., Wenger, T., Dumond, J., Bogetto, N., Reboud-Ravaux, M., Schramm, H. J., Schramm, W., Sheynis, T., Rozner, S., Kolusheva, S., Satchell, D., Jelnik, R., Shigeta, Y., Imanaka, H., Ando, H., Makino, T., Kurohane, K., Oku, N., Baba, N., Shimizu, K., Asai, T., Takada, M., Baba, K., Namba, Y., Oku, N., Simberg, Dmitri, Danino, Dganit, Talmon, Yeshayahu, Minsky, Abraham, Ferrari, Marilyn E., Wheeler, Carl J., Barenholz, Yechezkel, Takada, Miki, Shimizu, Kosuke, Kuromi, Koici, Asai, Tomohiro, Baba, Kazuhiko, Oku, Naoto, Takeuchi, Y., Kurohane, K., North, J. R., Namba, Y., Nango, M., Oku, N., Tewes, B., Köchling, T., Deissler, M., Kühl, C., Marx, U., Strote, G., Gropp, F., Qualls, Marquita M., Kim, Jong-Mok, Thompson, David H., Zhang, Zhi-Yi, Shum, Pochi, Collier, Joel H., Hu, Bi-Huang, Ruberti, Jeffrey W., Messersmith, Phillip B., Thompson, David H., Tsuruda, T., Nakade, A., Sadzuka, Y., Hirota, S., Sonobe, T., Vorauer-Uhl, K., Wagner, A., Katinger, H., Wagner, A., Vorauer-Uhl, K., Katinger, H., Weeke-Klimp, A. H., Bartsch, M., Meijer, D. K. F., Scherphof, G. L., Kamps, J. A. A. M., Zeisig, R., Walther, W., Reß, A., Fichtner, I., Zschörnig, O., Schiller, J., Süß, M., Bergmeier, C., Arnold, K., Nchinda, Godwin, Überla, Klaus, and Zschörnig, Olaf

Abstract

DOCSPER—A Synthetic Lipid Fit for In Vivo ApplicationDOCSPER [1,3-Dioleoyloxy-2-(N5-carbamoyl-spermine)-propane] is a cationic amphiphile consisting of a hydrophobic 1,3 dioleylglycerol moiety and threefold positively charged spermine head group (1). We optimised the 5-step-synthesis of the lipospermine and after up-scaling we have obtained sufficient amounts to initiate preclinical investigations. DOCSPER was tested for its ability to transfect eukaryotic cells in vitro. It has proven to possess high transfection efficiency in comparison to commercially available liposomal transfection agents. Furthermore, DOCSPER was extensively tested in several in vivo studies (23). These studies revealed a high transfection efficiency, whereas very low toxicity levels were detected. Thus, the results clearly indicate that the cationic lipid DOCSPER is a reliable, low-risk system for broad applications in gene therapy.Groth D. et al. Int J Pharm 1998; 162:143–157.Nikol S. et al. Int J Angiol 2000; 9:87–95.Armeanu S. et al. Mol Ther 2000; 1(4):366–375.

Published
1982
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50. The immunoglobulin class of anti-hapten antibody secreted during secondary responses in vitro and in vivo

Author

North, J R and Dresser, D W

Subjects
Nitrophenols, Mice, Time Factors, Immunoglobulin G, Immunization, Passive, Animals, Immunoglobulins, chemical and pharmacologic phenomena, Haptens, Immunologic Memory, Antibodies, Cells, Cultured, Research Article
Abstract

A comparison has been made of the in vitro and in vivo response of primed mouse spleen cells to the hapten DNP. The responses were analysed in terms of six classes (sub-classes) of humoral antibody directed against the cross-reacting hapten TNP. By comparison with the response in intact mice the adoptive secondary response is delayed by 3 days in addition to being somewhat lesser in magnitude. The timing of the response in vitro is similar to that observed in intact mice. The preponderant class in all three responses was gammaG1 with gammaA and gammaG3 secreting cells consistently comprising the smallest proportion of the total of antibody-secreting cells.

Published
1977

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