Search Results - "Greenhill, L. J"

TOWARD A NEW GEOMETRIC DISTANCE TO THE ACTIVE GALAXY NGC 4258. III. FINAL RESULTS AND THE HUBBLE CONSTANT by Humphreys, E M L, Reid, M J, Moran, J M, Greenhill, L J, Argon, A L

“…We report a new geometric maser distance estimate to the active galaxy NGC 4258. The data for the new model are maser line-of-sight (LOS) velocities and sky…”
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Bayesian constraints on the global 21-cm signal from the Cosmic Dawn by Bernardi, G., Zwart, J. T. L., Price, D., Greenhill, L. J., Mesinger, A., Dowell, J., Eftekhari, T., Ellingson, S. W., Kocz, J., Schinzel, F.

“…The birth of the first luminous sources and the ensuing epoch of reionization are best studied via the redshifted 21-cm emission line, the signature of the…”
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FIRST SEASON MWA EOR POWER SPECTRUM RESULTS AT REDSHIFT 7 by Beardsley, A. P., Hazelton, B. J., Sullivan, I. S., Carroll, P., Barry, N., Rahimi, M., Pindor, B., Trott, C. M., Line, J., Jacobs, Daniel C., Morales, M. F., Pober, J. C., Bernardi, G., Bowman, Judd D., Busch, M. P., Briggs, F., Cappallo, R. J., Corey, B. E., Oliveira-Costa, A. de, Dillon, Joshua S., Emrich, D., Ewall-Wice, A., Feng, L., Gaensler, B. M., Goeke, R., Greenhill, L. J., Hewitt, J. N., Hurley-Walker, N., Johnston-Hollitt, M., Kaplan, D. L., Kasper, J. C., Kim, H. S., Kratzenberg, E., Lenc, E., Loeb, A., Lonsdale, C. J., Lynch, M. J., McKinley, B., McWhirter, S. R., Mitchell, D. A., Morgan, E., Neben, A. R., Thyagarajan, Nithyanandan, Oberoi, D., Offringa, A. R., Ord, S. M., Paul, S., Prabu, T., Procopio, P., Riding, J., Rogers, A. E. E., Roshi, A., Shankar, N. Udaya, Sethi, Shiv K., Srivani, K. S., Subrahmanyan, R., Tegmark, M., Tingay, S. J., Waterson, M., Wayth, R. B., Webster, R. L., Whitney, A. R., Williams, A., Williams, C. L., Wu, C., Wyithe, J. S. B.

“…ABSTRACT The Murchison Widefield Array (MWA) has collected hundreds of hours of Epoch of Reionization (EoR) data and now faces the challenge of overcoming…”
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First limits on the 21 cm power spectrum during the Epoch of X-ray heating by Ewall-Wice, A., Dillon, Joshua S., Hewitt, J. N., Loeb, A., Mesinger, A., Neben, A. R., Offringa, A. R., Tegmark, M., Barry, N., Beardsley, A. P., Bernardi, G., Bowman, Judd D., Briggs, F., Cappallo, R. J., Carroll, P., Corey, B. E., de Oliveira-Costa, A., Emrich, D., Feng, L., Gaensler, B. M., Goeke, R., Greenhill, L. J., Hazelton, B. J., Hurley-Walker, N., Johnston-Hollitt, M., Jacobs, Daniel C., Kaplan, D. L., Kasper, J. C., Kim, HS, Kratzenberg, E., Lenc, E., Line, J., Lonsdale, C. J., Lynch, M. J., McKinley, B., McWhirter, S. R., Mitchell, D. A., Morales, M. F., Morgan, E., Thyagarajan, Nithyanandan, Oberoi, D., Ord, S. M., Paul, S., Pindor, B., Pober, J. C., Prabu, T., Procopio, P., Riding, J., Rogers, A. E. E., Roshi, A., Shankar, N. Udaya, Sethi, Shiv K., Srivani, K. S., Subrahmanyan, R., Sullivan, I. S., Tingay, S. J., Trott, C. M., Waterson, M., Wayth, R. B., Webster, R. L., Whitney, A. R., Williams, A., Williams, C. L., Wu, C., Wyithe, J. S. B.

“…We present first results from radio observations with the Murchison Widefield Array seeking to constrain the power spectrum of 21 cm brightness temperature…”
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The Megamaser Cosmology Project. I. Very Long Baseline Interferometric Observations of UGC 3789 by Reid, M. J, Braatz, J. A, Condon, J. J, Greenhill, L. J, Henkel, C, Lo, K. Y

“…The Megamaser Cosmology Project (MCP) seeks to measure the Hubble Constant (H 0) in order to improve the extragalactic distance scale and constrain the nature…”
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A New Cepheid Distance to the Maser-Host Galaxy NGC 4258 and Its Implications for the Hubble Constant by Macri, L. M, Stanek, K. Z, Bersier, D, Greenhill, L. J, Reid, M. J

“…We present initial results from a time series BVI survey of two fields in NGC 4258 using the HST ACS. This galaxy was selected because of its accurate…”
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LOW-FREQUENCY OBSERVATIONS OF LINEARLY POLARIZED STRUCTURES IN THE INTERSTELLAR MEDIUM NEAR THE SOUTH GALACTIC POLE by Lenc, E., Gaensler, B. M., Sun, X. H., Sadler, E. M., Willis, A. G., Barry, N., Beardsley, A. P., Bell, M. E., Bernardi, G., Bowman, J. D., Briggs, F., Callingham, J. R., Cappallo, R. J., Carroll, P., Corey, B. E., Oliveira-Costa, A. de, Deshpande, A. A., Dillon, J. S., Dwarkanath, K. S., Emrich, D., Ewall-Wice, A., Feng, L., For, B.-Q., Goeke, R., Greenhill, L. J., Hancock, P., Hazelton, B. J., Hewitt, J. N., Hindson, L., Hurley-Walker, N., Johnston-Hollitt, M., Jacobs, D. C., Kapi ska, A. D., Kaplan, D. L., Kasper, J. C., Kim, H.-S., Kratzenberg, E., Line, J., Loeb, A., Lonsdale, C. J., Lynch, M. J., McKinley, B., McWhirter, S. R., Mitchell, D. A., Morales, M. F., Morgan, E., Morgan, J., Murphy, T., Neben, A. R., Oberoi, D., Offringa, A. R., Ord, S. M., Paul, S., Pindor, B., Pober, J. C., Prabu, T., Procopio, P., Riding, J., Rogers, A. E. E., Roshi, A., Shankar, N. Udaya, Sethi, S. K., Srivani, K. S., Staveley-Smith, L., Subrahmanyan, R., Sullivan, I. S., Tegmark, M., Thyagarajan, Nithyanandan, Tingay, S. J., Trott, C., Waterson, M., Wayth, R. B., Webster, R. L., Whitney, A. R., Williams, A., Williams, C. L., Wu, C., Wyithe, J. S. B., Zheng, Q.

“…ABSTRACT We present deep polarimetric observations at 154 MHz with the Murchison Widefield Array (MWA), covering 625 deg2 centered on = 0hand δ = −27°. The…”
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Limits on Fast Radio Bursts and other transient sources at 182 MHz using the Murchison Widefield Array by Rowlinson, A., Bell, M. E., Murphy, T., Trott, C. M., Hurley-Walker, N., Johnston, S., Tingay, S. J., Kaplan, D. L., Carbone, D., Hancock, P. J., Feng, L., Offringa, A. R., Bernardi, G., Bowman, J. D., Briggs, F., Cappallo, R. J., Deshpande, A. A., Gaensler, B. M., Greenhill, L. J., Hazelton, B. J., Johnston-Hollitt, M., Lonsdale, C. J., McWhirter, S. R., Mitchell, D. A., Morales, M. F., Morgan, E., Oberoi, D., Ord, S. M., Prabu, T., Udaya Shankar, N., Srivani, K. S., Subrahmanyan, R., Wayth, R. B., Webster, R. L., Williams, A., Williams, C. L.

“…We present a survey for transient and variable sources, on time-scales from 28 s to ∼1 yr, using the Murchison Widefield Array (MWA) at 182 MHz. Down to a…”
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The Geometry of and Mass Accretion Rate through the Maser Accretion Disk in NGC 4258 by Herrnstein, J. R, Moran, J. M, Greenhill, L. J, Trotter, Adam S

“…A maximum likelihood analysis of the NGC 4258 maser positions and velocities reveals a 62 s deviation from Keplerian motion in the projected rotation curve of…”
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A multifrequency radio continuum study of the Magellanic Clouds – I. Overall structure and star formation rates by For, B-Q, Staveley-Smith, L, Hurley-Walker, N, Franzen, T, Kapińska, A D, Filipović, M D, Collier, J D, Wu, C, Grieve, K, Callingham, J R, Bell, M E, Bernardi, G, Bowman, J D, Briggs, F, Cappallo, R J, Deshpande, A A, Dwarakanath, K S, Gaensler, B M, Greenhill, L J, Hancock, P, Hazelton, B J, Hindson, L, Johnston-Hollitt, M, Kaplan, D L, Lenc, E, Lonsdale, C J, McKinley, B, McWhirter, S R, Mitchell, D A, Morales, M F, Morgan, E, Morgan, J, Oberoi, D, Offringa, A, Ord, S M, Prabu, T, Procopio, P, Shankar, N Udaya, Srivani, K S, Subrahmanyan, R, Tingay, S J, Wayth, R B, Webster, R L, Williams, A, Williams, C L, Zheng, Q

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Accelerating radio astronomy cross-correlation with graphics processing units by Clark, M.A., Plante, PC La, Greenhill, L.J.

“…We present a highly parallel implementation of the cross-correlation of time-series data using graphics processing units (GPUs), which is scalable to hundreds…”
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A Warped Accretion Disk and Wide-Angle Outflow in the Inner Parsec of the Circinus Galaxy by Greenhill, L. J, Booth, R. S, Ellingsen, S. P, Herrnstein, J. R, Jauncey, D. L, McCulloch, P. M, Moran, J. M, Norris, R. P, Reynolds, J. E, Tzioumis, A. K

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Imaging the Ionized Disk of the High-Mass Protostar Orion I by Reid, M. J, Menten, K. M, Greenhill, L. J, Chandler, C. J

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A geometric distance to the galaxy NGC4258 from orbital motions in a nuclear gas disk by Herrnstein, J. R, Moran, J. M, Greenhill, L. J, Diamond, P. J, Inoue, M, Nakai, N, Miyoshi, M, Henkel, C, Riess, A

“…The accurate measurement of extragalactic distances is a central challenge of modern astronomy, being required for any realistic description of the age,…”
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Toward a New Geometric Distance to the Active Galaxy NGC 4258. II. Centripetal Accelerations and Investigation of Spiral Structure by Humphreys, E. M. L, Reid, M. J, Greenhill, L. J, Moran, J. M, Argon, A. L

“…We report measurements of centripetal accelerations of maser spectral components of NGC 4258 for 51 epochs spanning 1994 to 2004. This is the second paper of a…”
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Maser Emission from SiO Isotopologues Traces the Innermost 100 AU Around Radio Source I in Orion Becklin–Neugebauer/Kleinmann-Low by Goddi, C, Greenhill, L. J, Chandler, C. J, Humphreys, E. M. L, Matthews, L. D, Gray, M. D

“…We have used the Very Large Array at 7 mm wavelength to image five rotational transitions (J = 1-0) from three SiO isotopologues toward Orion…”
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Subtraction of point sources from interferometric radio images through an algebraic forward modelling scheme by Bernardi, G., Mitchell, D. A., Ord, S. M., Greenhill, L. J., Pindor, B., Wayth, R. B., Wyithe, J. S. B.

“…We present a method for subtracting point sources from interferometric radio images via forward modelling of the instrument response and involving an algebraic…”
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Suzaku Observations of the Circinus Galaxy by Yang, Y, Wilson, A. S, Matt, G, Terashima, Y, Greenhill, L. J

“…We report Suzaku observations of the active, Compton-thick Circinus galaxy. Observations were obtained with both the X-ray imaging spectrometer (XIS) and the…”
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A Feature Movie of SiO Emission 20-100 AU from the Massive Young Stellar Object Orion Source I by Matthews, L. D, Greenhill, L. J, Goddi, C, Chandler, C. J, Humphreys, E. M. L, Kunz, M. W

“…We present multi-epoch Very Long Baseline Array imaging of the 28SiO v = 1 and v = 2, J = 1-0 maser emission toward the massive young stellar object (YSO)…”
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Toward a New Geometric Distance to the Active Galaxy NGC 4258. I. VLBI Monitoring of Water Maser Emission by Argon, A. L, Greenhill, L. J, Reid, M. J, Moran, J. M, Humphreys, E. M. L

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