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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

J. L. Scali, B. W. Reinisch, M. C. Kelley, Clark A. Miller, Wesley E. Swartz, Qihou Zhou, S. M. Radicella,

... World Day Campaign with three separate instruments: the Arecibo incoherent scatter radar, the Ramey Digisonde (located 50 km west of Arecibo), and the Puerto Madryn, Argentina, Digisonde (located 400 km from the magnetic conjugate point of Arecibo). F layer peak heights from Ramey agree well with those from Arecibo throughout the entire 10‐day period, with a ... the electron density that is commonly observed at Arecibo in the winter months. However, this periodic temporal ... a higher geographic latitude. Only occasionally do the Arecibo incoherent scatter radar and the Ramey Digisonde velocity ...

Tópico(s): Earthquake Detection and Analysis

1997 - American Geophysical Union | Journal of Geophysical Research Atmospheres

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Revisado por pares

D. B. Campbell, N.J.S. Stacy, A. A. Hine,

Arecibo high resolution radar data covering approximately 23% of the surface of Venus was analyzed for circular ... used to verity crater diameters measured from the Arecibo data. A comparison of the diameter‐frequency distribution of the possible impact features in the Arecibo data for northern latitudes south of 40°N ... but a deficiency of smaller craters in the Arecibo data. The average crater density measured for all ... 106 ×l0 6 km 2 covered by the Arecibo data was 0.95 per 10 6 km ... km 2 for the average of the two Arecibo data regions. All circular features in the Arecibo ...

Tópico(s): Space Exploration and Technology

1990 - American Geophysical Union | Geophysical Research Letters

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

Yanlin Li, Qihou Zhou, Julio Urbina, Tai‐Yin Huang,

... of sporadic meteor radiant density distribution using the Arecibo 430 MHz incoherent scatter radar (ISR) located in ... meteor studies have been carried out using the Arecibo ISR, meteoroid radiant density distribution has remained a mystery as the Arecibo radar cannot measure vector velocity. A numerical orbital ... corresponding speed distributions of the meteors observed at Arecibo. The data set for the algorithm comprises over 250 000 meteors from Arecibo observations between 2009 and 2017. Five of the ...

Tópico(s): Ionosphere and magnetosphere dynamics

2022 - Oxford University Press | Monthly Notices of the Royal Astronomical Society

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

T. M. Bania, L. D. Anderson, Dana S. Balser,

... of radio recombination line (RRL) emission using the Arecibo Observatory at X band (9 GHz, 3 cm) ... zone 66° ⩾ ℓ ⩾ 31° and | b | ⩽ 1°. This Arecibo H ii Region Discovery Survey (Arecibo HRDS) is a continuation of the Green Bank Telescope (GBT) HRDS. The targets for the Arecibo HRDS have spatially coincident 24 μm and 20 ... angular morphology and extent. To take advantage of Arecibo's sensitivity and small beam size, sources in ... compared to those of the GBT HRDS. These Arecibo nebulae are some of the faintest H ii ... We derive kinematic distances to 23 of the Arecibo HRDS detections. Four nebulae have negative local standard ...

Tópico(s): Astrophysics and Cosmic Phenomena

2012 - IOP Publishing | The Astrophysical Journal

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

Jiuhou Lei, R. G. Roble, Wenbin Wang, B. A. Emery, Shun‐Rong Zhang,

... Hill (42.6°N, 71.5°W) and Arecibo (18.3°N, 66.7°W) are compared ... is characterized by morning and evening peaks at Arecibo and by a morning peak at Millstone Hill. The occurrence and strength of the peaks at Arecibo are significantly different from those at Millstone Hill. ... with solar activity in equinox and summer at Arecibo, whereas it does so only in summer at ... peak is weaker than that from observations at Arecibo. The simulations show that the daytime bulge of ... significant morning peak at low solar activity over Arecibo is associated with the equatorial anomaly. Moreover, an ...

Tópico(s): Earthquake Detection and Analysis

2007 - American Geophysical Union | Journal of Geophysical Research Atmospheres

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Revisado por pares

S. J. Ostro, Lance A. M. Benner, C. Magri, Jon D. Giorgini, Randy Rose, R. F. Jurgens, D. K. Yeomans, A. A. Hine, M. C. Nolan, Daniel J. Scheeres, Stephen B. Broschart, M. Kaasalainen, Jean‐Luc Margot,

... by this authorAlice A. Hine, Alice A. Hine Arecibo Observatory, HC3 Box 53995, Arecibo, Puerto Rico 00612, USASearch for more papers by this authorMichael C. Nolan, Michael C. Nolan Arecibo Observatory, HC3 Box 53995, Arecibo, Puerto Rico 00612, USASearch for more papers by ... by this authorAlice A. Hine, Alice A. Hine Arecibo Observatory, HC3 Box 53995, Arecibo, Puerto Rico 00612, USASearch for more papers by this authorMichael C. Nolan, Michael C. Nolan Arecibo Observatory, HC3 Box 53995, Arecibo, Puerto Rico 00612, ...

Tópico(s): Astro and Planetary Science

2005 - Wiley | Meteoritics and Planetary Science

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

F. T. Djuth, L. D. Zhang, Dorey J. Livneh, Ilgın Şeker, S. M. Smith, M. P. Sulzer, J. D. Mathews, R. L. Walterscheid,

... e have been observed in the thermosphere above Arecibo Observatory, Puerto Rico throughout its 45 year history. ... that these waves are continuously present in the Arecibo thermosphere. The wave characteristics are fairly constant between ... internal acoustic‐gravity waves (AGWs) propagating through the Arecibo thermosphere. The AGWs appear to be broadbanded in ... do not appear to be consistent with the Arecibo observations of a continuous flux of background AGWs. ... that is roughly 2100 km east northeast of Arecibo. Internal ocean waves generated in response to the ...

Tópico(s): Ocean Waves and Remote Sensing

2010 - American Geophysical Union | Journal of Geophysical Research Atmospheres

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

Bengt Eliasson, G. M. Milikh, T. C. Liu, Xi Shao, K. Papadopoulos,

... was reported during the HF heating experiment at Arecibo (Bernhardt et al., 2017, https://ies2017.bc.edu/ ). This result was unexpected since Arecibo has the effective radiated power 4–5 times ... Auroral Research Program, and since the experiment at Arecibo also has an unfavorable geometry, where the HF ... from the Sun at the low latitude of Arecibo could magnify the flux of hot electrons. A model of artificial plasma layers created by the Arecibo HF facility is presented. It shows that Langmuir ...

Tópico(s): Astro and Planetary Science

2018 - Wiley | Journal of Geophysical Research Space Physics

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

Jonathan S. Friedman, Xinzhao Chu,

... the mesopause region (80–105 km) above the Arecibo Observatory, Puerto Rico (18.35°N, 66.75° ... in the nocturnal means are much weaker at Arecibo. Seasonally large inversions occur in summer but are ... existent during the rest of the year. The Arecibo climatology shows a three‐level mesopause: a high ... K. The lower thermosphere around 100 km at Arecibo shows a decreasing temperature from spring to summer ... through most of the MLT altitude range at Arecibo. These observed seasonal variations appear to be associated ...

Tópico(s): Solar and Space Plasma Dynamics

2007 - American Geophysical Union | Journal of Geophysical Research Atmospheres

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

Riccardo Giovanelli, Martha P. Haynes, Brian R. Kent, Philip Perillat, Barbara Catinella, G. L. Hoffman, Emmanuel Momjian, Jessica L. Rosenberg, A. Saintonge, Kristine Spekkens, Sabrina Stierwalt, N. Brosch, Karen L. Masters, Christopher M. Springob, И. Д. Караченцев, V. E. Karachentseva, Rebecca A. Koopmann, Erik Muller, W. van Driel, Liese van Zee,

In preparation for the full Arecibo Legacy Fast ALFA (ALFALFA) extragalactic H I survey, precursor observations were carried out in 2004 August–September with the seven-beam Arecibo L-band Feed Array (ALFA) receiver system and the Wideband Arecibo Pulsar Processor spectral processors. While these observations were ... the single-beam L-band wide system at Arecibo in 2005 January–February. Of those, 41% were ... time. Because of the higher sensitivity of the Arecibo system, fewer than 10% of the 166 H ...

Tópico(s): Astrophysics and Cosmic Phenomena

2005 - Institute of Physics | The Astronomical Journal

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

Aeree Chung, J. H. van Gorkom, K. O’Neil, G. D. Bothun,

... strongly deviate from the TF relation based on Arecibo single-dish observations. We do not detect three ... LSBs have bright galaxies which have contaminated the Arecibo signal. A further examination of the Arecibo sample shows that five out of the six ... not detected by us. A new observation by Arecibo did not confirm the earlier detection. The integrated ... of the bright galaxies are consistent with the Arecibo results both in velocity range and amplitude, which ... recent determination of the sidelobe structure of the Arecibo beam supports our conclusion and shows that the ...

Tópico(s): Stellar, planetary, and galactic studies

2002 - Institute of Physics | The Astronomical Journal

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Revisado por pares

D. D. Meisel, Diego Janches, J. D. Mathews,

Size histograms of all Arecibo ultra-high-frequency radar micrometeors detected in 1997-1998 whose radii were measured by atmospheric drag are presented. Most can ... deemed to be true interstellar particles (ISPs). The Arecibo IDP power-law results are shown to agree ... only once. A small sample of previously undetected Arecibo postperihelion ISPs coming from the direction of the ... and solar system dynamical properties similar to other Arecibo ISPs and therefore can be combined with previous ... robust sample. Derived mass flux points for the Arecibo ISPs agree well (over 5 orders of magnitude ...

Tópico(s): Astrophysics and Star Formation Studies

2002 - IOP Publishing | The Astrophysical Journal

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Revisado por pares

F. T. Djuth, C. A. Gonzales, H. M. Ierkic,

... high‐power high‐frequency (HF) facility located near Arecibo, Puerto Rico. Observations were made with the Arecibo 430‐MHz radar. In the current work, attention ... cycles. Under a variety of observing conditions, the Arecibo HFPLs are found to develop dominant decay line ... for the 430‐MHz HFPLs observed in the Arecibo F region. However, the formation of solitons may ... and temporal development of strongly excited HFPLs at Arecibo.

Tópico(s): GNSS positioning and interference

1986 - American Geophysical Union | Journal of Geophysical Research Atmospheres

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Acesso aberto Revisado por pares

Joseph K. Swiggum, D. R. Lorimer, M. A. McLaughlin, S. D. Bates, D. J. Champion, S. M. Ransom, P. Lazarus, Adam Brazier, J. W. T. Hessels, D. J. Nice, Justin A. Ellis, T. R. Senty, B. Allen, N. D. R. Bhat, Slavko Bogdanov, F. Camilo, Shami Chatterjee, J. M. Cordes, F. Crawford, J. S. Deneva, P. C. C. Freire, F. A. Jenet, C. Karako-Argaman, V. M. Kaspi, Benjamin Knispel, K. J. Lee, J. van Leeuwen, Ryan S. Lynch, A. G. Lyne, Paul Scholz, Xavier Siemens, I. H. Stairs, B. W. Stappers, K. Stovall, A. Venkataraman, Weiwei Zhu,

The Pulsar Arecibo L-band Feed Array (PALFA) Survey uses the ALFA 7-beam receiver to search both inner and outer Galactic sectors visible from Arecibo (32° ≲ ℓ ≲ 77° and 168° ≲ ℓ ≲ 214°) close ... distant than have previously been seen because of Arecibo's unrivaled sensitivity. In this paper we detail ... predominantly to the radio frequency interference environment at Arecibo and perhaps also scintillation—both effects that are ...

Tópico(s): Gamma-ray bursts and supernovae

2014 - IOP Publishing | The Astrophysical Journal

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Arecibo(pt.)

0000 - Gale Group | SASII

Artigo Revisado por pares

F. T. Djuth, M. P. Sulzer, Sergi Gonzales, J. D. Mathews, J. H. Elder, R. L. Walterscheid,

Previous incoherent radar studies at Arecibo Observatory, Puerto Rico have demonstrated that ∼1–3% electron density “imprints” of internal gravity waves are routinely present in the Arecibo thermosphere (∼118–500 km). A special radar technique ... that gravity waves are continually propagating through the Arecibo thermosphere, and that “sets” of waves separated by ... radar tests, it may be possible to unlock Arecibo power profiles recorded over the past 30 years ...

Tópico(s): Geophysics and Gravity Measurements

2004 - American Geophysical Union | Geophysical Research Letters