Browsing Faculty of Arts and Sciences by Author "Honma, Mareki"

Now showing items 1-6 of 6

    • 1.3 mm Wavelength VLBI of Sagittarius A*: Detection of Time-Variable Emission on Event Horizon Scales 

      Fish, Vincent L.; Doeleman, Sheperd Samuel; Beaudoin, Christopher; Blundell, Raymond; Bolin, David E.; Bower, Geoffrey C.; Chamberlin, Richard; Freund, Robert; Friberg, Per; Gurwell, Mark Andrew; Honma, Mareki; Inoue, Makoto; Krichbaum, Thomas P.; Lamb, James; Marrone, Daniel P.; Moran, James M.; Oyama, Tomoaki; Plambeck, Richard; Primiani, Rurik A.; Rogers, Alan E. E.; Smythe, Daniel L.; SooHoo, Jason; Strittmatter, Peter; Tilanus, Remo P. J.; Titus, Michael; Weintroub, Jonathan; Wright, Melvyn; Woody, David; Young, Ken Harbour; Ziurys, Lucy M. (IOP Publishing, 2011)
      Sagittarius A*, the ~4 × 106 M ☉ black hole candidate at the Galactic center, can be studied on Schwarzschild radius scales with (sub)millimeter wavelength very long baseline interferometry (VLBI). We report on 1.3 mm ...

    • 230 GHz VLBI observations of M87: event-horizon-scale structure at the enhanced very-high-energy γ-ray state in 2012 

      Akiyama, Kazunori; Lu, Ru-Sen; Fish, Vincent; Doeleman, Sheperd S.; Broderick, Avery; Dexter, Jason; Hada, Kazuhiro; Kino, Motoki; Nagai, Hiroshi; Honma, Mareki; Johnson, Michael D.; Algaba, Juan; Asada, Keiichi; Brinkerink, Christiaan; Blundell, Raymond; Bower, Geoffrey; Cappallo, Roger; Crew, Geoffrey; Dexter, Matt; Dzib, Sergio; Freund, Robert; Friberg, Per; Gurwell, Mark Andrew; Ho, Paul; Inoue, Makoto; Krichbaum, Thomas; Loinard, Laurent; MacMahon, David; Marrone, Daniel; Moran, James M.; Nakamura, Masanori; Nagar, Neil; Ortiz-Leon, Gisela; Plambeck, Richard; Pradel, Nicolas; Primiani, Rurik A.; Rogers, Alan; Roy, Alan; SooHoo, Jason; Tavares, Jonathan-León; Tilanus, Remo; Titus, Michael; Wagner, Jan; Weintroub, Jonathan; Yamaguchi, Paul Isami; Young, Ken Harbour; Zensus, Anton; Ziurys, Lucy (IOP Publishing, 2015)
      We report on 230 GHz (1.3 mm) VLBI observations of M87 with the Event Horizon Telescope using antennas on Mauna Kea in Hawaii, Mt. Graham in Arizona and Cedar Flat in California. For the first time, we have acquired 230 ...

    • Fine-Scale Structure of the Quasar 3C 279 Measured with 1.3 mm Very Long Baseline Interferometry 

      Lu, Ru-Sen; Fish, Vincent L.; Akiyama, Kazunori; Doeleman, Sheperd S.; Algaba, Juan C.; Bower, Geoffrey C.; Brinkerink, Christiaan; Chamberlin, Richard; Crew, Geoffrey; Cappallo, Roger J.; Dexter, Matt; Freund, Robert; Friberg, Per; Gurwell, Mark Andrew; Ho, Paul T. P.; Honma, Mareki; Inoue, Makoto; Jorstad, Svetlana G.; Krichbaum, Thomas P.; Loinard, Laurent; MacMahon, David; Marrone, Daniel P.; Marscher, Alan P.; Moran, James M.; Plambeck, Richard; Pradel, Nicolas; Primiani, Rurik A.; Tilanus, Remo P. J.; Titus, Michael; Weintroub, Jonathan; Wright, Melvyn; Young, Ken Harbour; Ziurys, Lucy M. (American Astronomical Society, 2013)
      We report results from five day very long baseline interferometry observations of the well-known quasar 3C 279 at 1.3mm (230 GHz) in 2011. The measured nonzero closure phases on triangles including stations in Arizona, ...

    • Limits on the Position Wander of Sgr A* 

      Reid, Mark J.; Broderick, Avery E.; Loeb, Abraham; Honma, Mareki; Brunthaler, Andreas (American Astronomical Society, 2008)
      We present measurements with the Very Long Baseline Array of the variability in the centroid position of Sgr A* relative to a background quasar at 7 mm wavelength. We find an average centroid wander of 71 +/- 45 mu as for ...

    • Persistent Asymmetric Structure of Sagittarius A* on Event Horizon Scales 

      Fish, Vincent; Johnson, Michael D.; Doeleman, Sheperd S.; Broderick, Avery; Psaltis, Dimitrios; Lu, Ru-Sen; Akiyama, Kazunori; Alef, Walter; Algaba, Juan; Asada, Keiichi; Beaudoin, Christopher; Bertarini, Alessandra; Blackburn, Lindy; Blundell, Raymond; Bower, Geoffrey; Brinkerink, Christiaan; Cappallo, Roger; Chael, Andrew Alan; Chamberlin, Richard; Chan, Chi-Kwan; Crew, Geoffrey; Dexter, Jason; Dexter, Matt; Dzib, Sergio; Falcke, Heino; Freund, Robert; Friberg, Per; Greer, Christopher; Gurwell, Mark Andrew; Ho, Paul; Honma, Mareki; Inoue, Makoto; Johannsen, Tim; Kim, Junhan; Krichbaum, Thomas; Lamb, James; León-Tavares, Jonathan; Loeb, Abraham; Loinard, Laurent; MacMahon, David; Marrone, Daniel; Moran, James M.; Mościbrodzka, Monika; Ortiz-León, Gisela; Oyama, Tomoaki; Özel, Feryal (American Astronomical Society, 2016)
      The Galactic Center black hole Sagittarius A* (Sgr A*) is a prime observing target for the Event Horizon Telescope (EHT), which can resolve the 1.3 mm emission from this source on angular scales comparable to that of the ...

    • Resolving the Inner Jet Structure of 1924-292 with the Event Horizon Telescope 

      Lu, Ru-Sen; Fish, Vincent L.; Weintroub, Jonathan; Doeleman, Sheperd S.; Bower, Geoffrey C.; Freund, Robert; Friberg, Per; Ho, Paul T. P.; Honma, Mareki; Inoue, Makoto; Krichbaum, Thomas P.; Marrone, Daniel P.; Moran, James M.; Oyama, Tomoaki; Plambeck, Richard; Primiani, Rurik; Shen, Zhi-Qiang; Tilanus, Remo P. J.; Wright, Melvyn; Young, Ken H.; Ziurys, Lucy M.; Zensus, J. Anton (American Astronomical Society, 2012)
      We present the first 1.3 mm (230 GHz) very long baseline interferometry model image of an active galactic nucleus (AGN) jet using closure phase techniques with a four-element array. The model image of the quasar 1924-292 ...