Trigonometric Parallaxes of 6.7 GHz Methanol Masers (2009)
Rygl, K. L. J., Brunthaler, A., Reid, M. J., Menten, K. M., Van Langevelde, H. J., Xu, Y.
Emission from the 6.7 GHz methanol maser transition is very strong, relatively stable, has small internal motions and is observed toward numerous massive star forming regions in the Galaxy. Our goal...
The radio lightcurve of SN 2008iz in M82 revealed by Urumqi observations (2009)
Marchili, N., Marti-Vidal, I., Brunthaler, A., Krichbaum, T. P., Mueller, P., Liu, X., ...
We report on a set of 5 GHz Urumqi observations of the galaxy M82, made between August 2005 and May 2009. From the resulting flux densities, we detect a strong flare, starting in March or April and...
Sanna, A., Reid, M. J., Moscadelli, L., Dame, T. M., Menten, K. M., Brunthaler, A., ...
We report a trigonometric parallax of 12 GHz methanol masers associated with the massive star forming region G9.62+0.20, corresponding to a distance of 5.2+-0.6 kpc. With a local standard of rest...
Absolute positions of 6.7-GHz methanol masers (2009)
Xu, Y., Voronkov, M. A., Pandian, J. D., Li, J. J., Sobolev, A. M., Brunthaler, A., ...
The ATCA, MERLIN and VLA interferometers were used to measure the absolute positions of 35 6.7 GHz methanol masers to subarcsecond or higher accuracy. Our measurements represent essential preparatory...
A Trigonometric Parallax of Sgr B2 (2009)
Reid, M. J., Menten, K. M., Zheng, X. W., Brunthaler, A., Xu, Y.
We have measured the positions of water masers in Sgr B2, a massive star forming region in the Galactic center, relative to an extragalactic radio source with the Very Long Baseline Array. The...
Simultaneous Multi-Wavelength Observations of Sgr A* during 2007 April 1-11 (2009)
Yusef-Zadeh, F., Bushouse, H., Wardle, M., Heinke, C., Roberts, D. A., Dowell, C. D., ...
We report the detection of variable emission from Sgr A* in almost all wavelength bands (i.e. centimeter, millimeter, submillimeter, near-IR and X-rays) during a multi-wavelength observing campaign....
Discovery of a bright radio transient in M82: a new radio supernova? (2009)
Brunthaler, A., Menten, K. M., Reid, M. J., Henkel, C., Bower, G. C., Falcke, H.
In this Letter, we report the discovery of a new bright radio transient in M82. Using the Very Large Array, we observed the nuclear region of M82 at several epochs at 22 GHz and detected a new bright...
Reid, M. J., Menten, K. M., Zheng, X. W., Brunthaler, A., Moscadelli, L., Xu, Y., ...
We are using the NRAO Very Long Baseline Array (VLBA) and the Japanese VERA project to measure trigonometric parallaxes and proper motions of masers found in high-mass star-forming regions across the...
Structure and Dynamics of the Milky Way: an Astro2010 Science White Paper (2009)
Reid, M. J., Menten, K. M., Brunthaler, A., Moellenbrock, G. A.
Recent advances in radio astrometry with the VLBA have resulted in near micro-arcsecond accurate trigonometric parallax and proper motion measurements for masers in star forming regions. We are now...
Motions of Galaxies in the Local Group and Beyond: an Astro2010 Science White Paper (2009)
Reid, M. J., Brunthaler, A., Menten, K. M., Loinard, L., Wrobel, J.
Recent advances with the VLBA have resulted in ~10 micro-arcsec astrometry for compact sources in external galaxies, and measurement of the proper motion of Local Group galaxies has been...
Evidence of a pure starburst nature of the nuclear region of NGC 253 (2009)
Brunthaler, A., Castangia, P., Tarchi, A., Henkel, C., Reid, M. J., Falcke, H., ...
We present high-resolution spectral line and continuum VLBI and VLA observations of the nuclear region of NGC 253 at 22 GHz. While the water vapor masers in this region were detected on arcsecond and...
The distance to a star forming region in the Outer arm of the Galaxy (2009)
Hachisuka, K., Brunthaler, A., Menten, K. M., Reid, M. J., Hagiwara, Y., Mochizuki, N.
We performed astrometric observations with the VLBA of WB89-437, an H2O maser source in the Outer spiral arm of the Galaxy. We measure an annual parallax of 0.167 +/- 0.006 mas, corresponding to a...
A gravitationally lensed water maser in the early Universe (2009)
Impellizzeri, C. M. V., McKean, J. P., Castangia, P., Roy, A. L., Henkel, C., Brunthaler, A., ...
Water masers are found in dense molecular clouds closely associated with supermassive black holes in the centres of active galaxies. Based upon the understanding of the local water maser luminosity...
Distances to Galactic methanol masers (2008)
Rygl, K. L. J., Brunthaler, A., Menten, K. M., Reid, M. J., Van Langevelde, H. J.
We present the first EVN parallax measurements of 6.7 GHz methanol masers in star forming regions of the Galaxy. The 6.7 GHz methanol maser transition is a very valuable astrometric tool, for its...
Trigonometric Parallaxes of Massive Star Forming Regions: II. Cep A & NGC 7538 (2008)
Moscadelli, L., Reid, M. J., Menten, K. M., Brunthaler, A., Zheng, X. W., Xu, Y.
We report trigonometric parallaxes for the sources NGC 7538 and Cep A, corresponding to distances of 2.65 [+0.12/-0.11] kpc and 0.70 [+0.04/-0.04] kpc, respectively. The distance to NGC 7538 is...
Trigonometric Parallaxes of Massive Star Forming Regions: III. G59.7+0.1 and W 51 IRS2 (2008)
Xu, Y., Reid, M. J., Menten, K. M., Brunthaler, A., Zheng, X. W., Moscadelli, L.
We report trigonometric parallaxes for G59.7+0.1 and W 51 IRS2, corresponding to distances of 2.16^{+0.10}_{-0.09} kpc and 5.1^{+2.9}_{-1.4} kpc, respectively. The distance to G59.7+0.1 is smaller...
Trigonometric Parallaxes of Massive Star Forming Regions: IV. G35.20-0.74 and G35.20-1.74 (2008)
Zhang, B., Zheng, X. W., Reid, M. J., Menten, K. M., Xu, Y., Moscadelli, L., ...
We report trigonometric parallaxes for the high-mass star forming regions G35.20-0.74 and G35.20-1.74, corresponding to distances of 2.19 (+0.24 -0.20) kpc and 3.27 (+0.56 -0.42) kpc, respectively....
Trigonometric Parallaxes of Massive Star Forming Regions: V. G23.01-0.41 and G23.44-0.18 (2008)
Brunthaler, A., Reid, M. J., Menten, K. M., Zheng, X. W., Moscadelli, L., Xu, Y.
We report trigonometric parallaxes for the massive star-forming regions G23.01-0.41 and G23.44-0.18, corresponding to distances of 4.59 [+0.38/-0.33] kpc and 5.88 [+1.37/-0.93] kpc, respectively. The...
Trigonometric Parallaxes of Massive Star Forming Regions: I. S 252 & G232.6+1.0 (2008)
Reid, M. J., Menten, K. M., Brunthaler, A., Zheng, X. W., Moscadelli, L., Xu, Y.
We are conducting a large program with the NRAO Very Long Baseline Array (VLBA) to measure trigonometric parallaxes of massive star-forming regions across the Milky Way. Here we report measurement of...
The nature of the methanol maser ring G23.657-00.127 (2008)
Bartkiewicz, A., Brunthaler, A., Szymczak, M., Van Langevelde, H. J., Reid, M. J.
Methanol masers are associated with young high-mass stars and are an important tool for investigating the process of massive star formation. The recently discovered methanol maser ring in...
A. Brunthaler, H. Falcke, G. C. Bower, M. F. Aller, H. D. Aller, T. P. Krichbaum
A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are:
A. Brunthaler, H. Falcke, G. C. Bower, M. Aller, H. Aller
III Zw 2: superluminal motion and compact lobe expansion in a Seyfert galaxy
R. Schilizzi, A. Brunthaler, H. Falcke, G. C. Bower, M. Aller, H. Aller
Galaxies and their constituents at the highest angular resolutions
The innermost region of the water megamaser radio galaxy 3C403 (2007)
Tarchi, A., Brunthaler, A., Henkel, C., Menten, K. M., Braatz, J., Weiss, A.
The standard unified scheme of active galactic nuclei requires the presence of high column densities of gas and dust potentially obscuring the central engine. So far, few direct subarcsecond...
The distance to the Orion Nebula (2007)
Menten, K. M., Reid, M. J., Forbrich, J., Brunthaler, A.
We have used the Very Long Baseline Array to measure the trigonometric parallax of several member stars of the Orion Nebula Cluster showing non-thermal radio emission. We have determined the distance...
Proper Motions in the Andromeda Subgroup (2007)
Brunthaler, A., Reid, M. J., Falcke, H., Henkel, C., Menten, K. M.
This article presents results of VLBI observations of regions of H2O maser activity in the Local Group galaxies M33 and IC10. Since all position measurements were made relative to extragalactic...
Towards a kinematic model of the Local Group (2006)
Brunthaler, A., Reid, M. J., Falcke, H., Henkel, C., Menten, K. M.
Measuring the proper motions and geometric distances of galaxies within the Local Group is very important for our understanding of the history, present state and future of the Local Group. Currently,...
The Proper Motion of the Local Group Galaxy IC 10 (2006)
Brunthaler, A., Reid, M. J., Falcke, H., Henkel, C., Menten, K. M.
We have measured the proper motion of the Local Group galaxy IC 10 with the Very Long Baseline Array by measuring the position of an H2O maser relative to two background quasars over 4.3 years. After...
Water masers in the Local Group of galaxies (2006)
Brunthaler, A., Henkel, C., Reid, M. J., Greenhill, L. J., Falcke, H.
We compare the number of detected 22 GHz H2O masers in the Local Group galaxies M31, M33, NGC6822, IC10, IC1613, DDO187, GR8, NGC185, and the Magellanic Clouds with the water maser population of the...
Water maser motions in W3(OH) and a determination of its distance (2005)
Hachisuka, K., Brunthaler, A., Menten, K. M., Reid, M. J., Imai, H., Hagiwara, Y., ...
We report phase-referencing VLBA observations of H2O masers near the star-forming region W3(OH) to measure their parallax and absolute proper motions. The measured annual parallax is 0.489 +/- 0.017...
The Geometric Distance and Proper Motion of the Triangulum Galaxy (M33) (2005)
Brunthaler, A., Reid, M. J., Falcke, H., Greenhill, L. J., Henkel, C.
We measured the angular rotation and proper motion of the Triangulum Galaxy (M33) with the Very Long Baseline Array by observing two H2O masers on opposite sides of the galaxy. By comparing the...
The extreme flare in III Zw 2: Evolution of a radio jet in a Seyfert galaxy (2005)
Brunthaler, A., Falcke, H., Bower, G. C., Aller, M. F., Aller, H. D., Teraesranta, H.
A very detailed monitoring of a radio flare in the Seyfert I galaxy III Zw 2 with the VLA and the VLBA is presented. The relative astrometry in the VLBA observations was precise on a level of a few...
The extreme flare in III Zw 2: Evolution of a radio jet in a Seyfert galaxy (2005)
Brunthaler, A., Falcke, H., Bower, G. C., Aller, M. F., Aller, H. D., Terasranta, H.
The geometric distance and proper motion of the Triangulum Galaxy (M33) (2005)
Brunthaler, A., Reid, M. J., Falcke, H., Greenhill, L. J., Henkel, C.
Probing the obscuring medium around active nuclei using masers : The case of 3C 403 (2005)
Tarchi, A., Henkel, C., Chiaberge, M., Menten, K. M., Brunthaler, A., Moscadelli, L.
Distance of W3(OH) by VLBI annual parallax measurement (2004)
Hachisuka, K., Brunthaler, A., Hagiwara, Y., Menten, K. M., Imai, H., Miyoshi, M., ...
The most powerful tool for measuring distances within our Galaxy is the annual parallax. We carried out phase-referencing VLBI observations of H$_{2}$O masers in the star forming region W3(OH) with...
Probing the obscuring medium around active nuclei using masers: The case of 3C403 (2004)
Tarchi, A., Henkel, C., Chiaberge, M., Menten, K. M., Brunthaler, A., Moscadelli, L.
We report the first detection of a water megamaser in a radio-loud galaxy, 3C403, and present a follow-up study using the VLA. 3C403 has been observed as a part of a small sample of FRII galaxies...
The Proper Motion of Sgr A*: II. The Mass of Sgr A* (2004)
We report measurements with the VLBA of the position of Sgr A* with respect to two extragalactic radio sources over a period of eight years. The apparent proper motion of \sgrab relative to J1745-283...
Distance of W3(OH) by VLBI annual parallax measurement (2004)
Hachisuka, K., Brunthaler, A., Hagiwara, Y., Menten, K. M., Imai, H., Miyoshi, M., ...
Atmosphere-Corrected Phase-Referencing (2003)
Brunthaler, A., Reid, M. J., Falcke, H.
One major problem of phase-referencing VLBI observations are phase errors due to the unknown tropospheric zenith delay at each antenna. These errors degrade the quality of the phase-referenced image...
The Position, Motion, and Mass of Sgr A* (2003)
Reid, M. J., Menten, K. M., Genzel, R., Ott, T., Schoedel, R., Eckart, A., ...
We report progress on measuring the position of Sgr A* on infrared images, placing limits on the motion of the central star cluster relative to Sgr A*, and measuring the proper motionof Sgr A*...
The Flaring H2O Megamaser and Compact Radio Source in Mrk 348 (2003)
Peck, A. B., Henkel, C., Ulvestad, J. S., Brunthaler, A., Falcke, H., Elitzur, M., ...
We report on single-dish monitoring and extremely high angular resolution observations of the flaring H2O megamaser in the Seyfert 2 galaxy Mrk 348. The H2O line is redshifted by ~130 km/s with...
The position, motion, and mass of SgrA* (2003)
Reid, M. J., Menten, K. M., Genzel, R., Ott, T., Schödel, R., Brunthaler, A.
III Zw 2 : evolution of a radio galaxy in a nutshell (2003)
Brunthaler, A., Falcke, H., Bower, G. C., Aller, M. F., Aller, H. D., Terasranta, H., ...
IIIZw 2 shows dramatic radio outbursts roughly every five years. Here we present the light curves and VLBA observations of the latest flare with an excellent time sampling. We have detected...
The flaring H2O megamaser and compact radio source in Markarian 348 (2003)
Peck, A. B., Henkel, C., Ulvestad, J. S., Brunthaler, A., Falcke, H., Elitzur, M., ...
We report on single-dish monitoring and extremely high angular resolution observations of the flaring H2O megamaser in the Seyfert 2 galaxy Mrk 348. The H2O line is redshifted by similar to130 km...
Towards Proper Motions in the Local Group (2002)
Brunthaler, A., Reid, M., Falcke, H., Greenhill, L. J., Henkel, C.
Key and still largely missing parameters for measuring the mass content and distribution of the Local Group are the proper motion vectors of its member galaxies. The problem when trying to derive the...
III Zw 2 : evolution of a radio galaxy in a nutshell. (2002)
Brunthaler, A., Falcke, H., Bower, G. C., Aller, M. F., Aller, H. D., Teräsranta, H., ...
Towards proper motions in the local group (2002)
Brunthaler, A., Reid, M., Falcke, H., Greenhill, L., Henkel, C.
Proceedings of the 6th European VLBI Network Symposium (2002)
Ros Porcas Lobanov, A. Brunthaler, M. Reid, H. Falcke, L. J. Greenhill, C. Henkel
Key and still largely missing parameters for measuring the mass content and distribution of the Local Group are the proper motion vectors of its member galaxies. The problem when trying to derive the...
Towards Proper Motions in the Local Group (2002)
Porcas R. W, J. A. (eds, A. Brunthaler, M. Reid, H. Falcke, L.J. Greenhill, ...
Key and still largely missing parameters for measuring the mass content and distribution of the Local Group are the proper motion vectors of its member galaxies. The problem when trying to derive the...
III Zw 2: Evolution of a Radio Galaxy in a Nutshell (2002)
A. Brunthaler, H. Falcke, G. C. Bower, M. F. Aller, H. D. Aller, H. Terasranta, ...
III Zw 2 shows dramatic radio outbursts roughly every five years. Here we present the results of our VLA and VLBA monitoring of the latest flare with an excellent time and frequency sampling. We have...
Detection of Circular Polarization in M81* (2001)
Brunthaler, A., Bower, G. C., Falcke, H., Mellon, R. R.
We report the detection of circular polarization in the compact radio jet of the nearby spiral galaxy M81 (M81*). The observations were made with the Very Large Array at 4.8 and 8.4 GHz and circular...
Detection of Circular Polarization in M81* (2001)
A. Brunthaler, G.C. Bower, H. Falcke, R. R. Mellon
We report the detection of circular polarization in the compact radio jet of the nearby spiral galaxy M81 (M81*). The observations were made with the Very Large Array at 4.8 and 8.4 GHz and circular...
III Zw 2: superluminal expansion and compact lobe expansion in a Seyfert galaxy (2000)
Brunthaler, A., Falcke, H., Bower, G. C., Aller, M. F., Aller, H. D., Teraesranta, H.
So far, all relativistically boosted jets with superluminal motion have only been detected in typical radio galaxies with early type host galaxies. We have now discovered superluminal motion in the...
III Zw 2, the first superluminal jet in a Seyfert galaxy (2000)
A. Brunthaler, H. Falcke, G.C. Bower, M. F. Aller, H. D. Aller, T. P. Krichbaum
. So far all relativistically boosted jets with superluminal motion have only been detected in typical radio galaxies with early type host galaxies. We have now discovered superluminal motion in the...
Temperature dependence of persistent photo-conductivity due to DX centers in AlxGa1-xAs-Si. (1990)
Conductivity and Hall effect measurements were performed on molecular beam epitaxy grown Al sub x Ga sub 1-x As:Si samples, which show a large persistent photoconductivity effect. We observe one,...