Zobrazeno 1 - 10
of 125
pro vyhledávání: '"Boboltz, D."'
Autor:
Malkin, Z., Jacobs, C. S., Arias, F., Boboltz, D., Boehm, J., Bolotin, S., Bourda, G., Charlot, P., De Witt, A., Fey, A., Gaume, R., Heinkelmann, R., Lambert, S., Ma, C., Nothnagel, A., Seitz, M., Gordon, D., Skurikhina, E., Souchay, J., Titov, O.
Publikováno v:
Proceedings of the Journees 2014 Systemes de Reference Spatio-temporels, St. Petersburg, Russia, 22-24 Sep 2014, Eds. Z. Malkin, N. Capitaine, 2015, pp.~3-8
The goal of this presentation is to report the latest progress in creation of the next generation of VLBI-based International Celestial Reference Frame, ICRF3. Two main directions of ICRF3 development are improvement of the S/X-band frame and extensi
Externí odkaz:
http://arxiv.org/abs/1511.08035
Despite their carbon-rich photospheres, silicate carbon stars show evidence of oxygen-rich circumstellar material, which is considered to exist in disks. Silicate carbon stars represent interesting cases that allow us to study the possible effects of
Externí odkaz:
http://arxiv.org/abs/1310.4516
We observed the AGB stars S Ori, GX Mon and R Cnc with the MIDI instrument at the VLTI. We compared the data to radiative transfer models of the dust shells, where the central stellar intensity profiles were described by dust-free dynamic model atmos
Externí odkaz:
http://arxiv.org/abs/1310.1924
Radio and infrared interferometry of SiO maser stars provide complementary information on the atmosphere and circumstellar environment at comparable spatial resolution. Here, we present the latest results on the atmospheric structure and the dust con
Externí odkaz:
http://arxiv.org/abs/1204.3546
We obtained 13 epochs of mid-infrared interferometry with the MIDI instrument at the VLTI between April 2004 and July 2007, covering pulsation phases 0.45-0.85 within four cycles. The data are modeled with a radiative transfer model of the dust shell
Externí odkaz:
http://arxiv.org/abs/1107.0909
Autor:
Wittkowski, M., Boboltz, D. A., Ireland, M., Karovicova, I., Ohnaka, K., Scholz, M., van Wyk, F., Whitelock, P., Wood, P. R., Zijlstra, A. A.
Publikováno v:
A&A, 532, L7 (2011)
We obtained K-band spectro-interferometric observations of the Miras R Cnc, X Hya, W Vel, and RW Vel with a spectral resolution of 1500 using the VLTI/AMBER instrument. We obtained concurrent JHKL photometry using the the Mk II instrument at the SAAO
Externí odkaz:
http://arxiv.org/abs/1107.0842
Autor:
Hungwe, F., Ojha, R., Booth, R. S., Bietenholz, M. F., Collioud, A., Charlot, P., Boboltz, D., Fey, A. L.
We present a detailed multi-epoch analysis of 31 potential southern hemisphere radio calibrators that were originally observed as part of a program to maintain the International Celestial Reference Frame (ICRF). At radio wavelengths, the primary cali
Externí odkaz:
http://arxiv.org/abs/1106.2669
Autor:
Wittkowski, M., Boboltz, D. A., Karovicova, I., Ohnaka, K., Ruiz-Velasco, A. E., Scholz, M., Zijlstra, A.
Publikováno v:
2011apn5.confE..66W
We present recent studies using the near-infrared instrument AMBER of the VLT Interferometer (VLTI) to investigate the structure and shaping processes within the extended atmosphere of AGB stars. Spectrally resolved near-infrared AMBER observations o
Externí odkaz:
http://arxiv.org/abs/1105.3392
Autor:
Wittkowski, M., Boboltz, D. A., de Breuck, C., Gray, M., Humphreys, E., Ireland, M., Karovicova, I., Ohnaka, K., Ruiz-Velasco, A. E., Scholz, M., Whitelock, P., Zijlstra, A.
We present an overview on our project to study the extended atmospheres and dust formation zones of Mira stars using coordinated observations with the Very Large Telescope Interferometer (VLTI), the Very Long Baseline Array (VLBA), and the Atacama Pa
Externí odkaz:
http://arxiv.org/abs/1105.3386
Autor:
Zavala, R. T., Hummel, C. A., Boboltz, D. A., Ojha, R., Shaffer, D. B., Tycner, C., Richards, M. T., Hutter, D. J.
Publikováno v:
Astrophysical Journal Letters 715, L44-48, 2010 May 20
Interacting binaries typically have separations in the milli-arcsecond regime and hence it has been challenging to resolve them at any wavelength. However, recent advances in optical interferometry have improved our ability to discern the components
Externí odkaz:
http://arxiv.org/abs/1005.0626