Observations of shocked [FeII] and H2 line profiles in orion bullet wakes     

Jonathan A. Tedds  Peter W. J. L. Brand  Michael G. Burton  Antonio Chrysostomou  Amadeu J. L. Fernandes 《Astrophysics and Space Science》1995,224(1-2):139-142

Recent near-IR imaging of the Orion molecular cloud has revealed a complex of dense bullets, visible as [FeII] emitting HH-objects at the tips of H₂ wakes, ejected explosively from the cloud core. Having resolved individual bow-shock structures for the first time in this bright source, we have observed [FeII] 1.644µm velocity profiles of selected bullets and H₂ 1-0 S(1), 2.122µm velocity profiles for a series of positions along and across the corresponding bow-shock wakes. We present observed profiles for the bullet M42 HH1 and its associated wake and compare with theoretical bow-shock models.  相似文献   

Molecular line mapping of the giant molecular cloud associated with RCW 106 – I. ¹³CO     

I. Bains  T. Wong  M. Cunningham  P. Sparks  D. Brisbin  P. Calisse  J. T. Dempsey  G. Deragopian  S. Ellingsen  B. Fulton  F. Herpin  P. Jones  Y. Kouba  C. Kramer  E. F. Ladd  S. N. Longmore  J. McEvoy  M. Maller  V. Minier  B. Mookerjea  C. Phillips  C. R. Purcell  A. Walsh  M. A. Voronkov  M. G. Burton 《Monthly notices of the Royal Astronomical Society》2006,367(4):1609-1628

  相似文献   

Shocked molecular hydrogen towards the Tornado nebula     

J. S. Lazendic  M. Wardle  M. G. Burton  F. Yusef-Zadeh  A. J. Green  J. B. Whiteoak 《Monthly notices of the Royal Astronomical Society》2004,354(2):393-400

  相似文献   

A catalogue of seismicity in Greece and adjacent areas   总被引：5，自引：0，他引：5  

Kostas C. Makropoullos  Paul W. Burton 《Geophysical Journal International》1981,65(3):741-762

Summary. A new earthquake catalogue for Greece has been formed to cover the instrumental period 1901–78, in particular 605 earthquakes for the period 1917–63 inclusive are relocated using first arrival data from the International Seismological Summary. These relocations incorporate macro-seismically and other well-controlled master events into an ensuing joint epicentre determination technique. The largest annual average shift is 165 km for 78 earthquakes during the decade after 1917, decreasing to 17 km for the later years 1957–63. Magnitudes are redetermined mainly using readings from the Swedish network and Uppsala since as early as 1908. Catalogue completeness exists for magnitudes around 5.5 for at least the last 60 years, but magnitudes of about 4.7 are completely reported only during the most recent 15 years.
The new epicentral positions lead to a better delineation of the seismic zones than has previously been achieved. The majority of shallow earthquakes are contained in a belt parallel to the Hellenic Arc which extends north into Albania, in the south-east the epicentral locations give a more diffuse extension of this zone into the west coast of Turkey. Depths of intermediate earthquakes along the Hellenic Arc tend to relocate to shallower depths, in the south-west part of Crete no earthquake focus deeper than 100 km is found, although in the south-eastern section of the arc a tendency to increased depths is observed. A second zone starts at Leukas Island in the west and extends through central Greece to near Volos on the east coast, where it divides into two branches, which are less well defined, but which eventually join the seismicity of western Turkey. A third zone follows the Saronikos and Corinth gulfs.  相似文献   

The mean lifetime of interstellar molecular clouds     

H.S. Liszt  W.B. Burton 《Chinese Astronomy and Astrophysics》1984,8(2):105-112

We describe the results of a study of the mean lifetime of molecular clouds based on actual observations. Using the model of growth from cloud-cloud collision and observations of ¹³CO along the galactic equator between longitudes 27°.85 and 40°, we derive a lower limit of 1 × 10⁹ yr for the lifetime of the interstellar molecular clouds  相似文献   

Seismotectonics and the earthquake frequency–magnitude distribution in the Aegean area     

Ian G. Main  Paul W. Burton 《Geophysical Journal International》1989,98(3):575-586

  相似文献   

Seismic risk in Turkey, the Aegean and the eastern Mediterranean: the occurrence of large magnitude earthquakes   总被引：1，自引：0，他引：1  

Paul W. Burton  Robert McGonigle  Kostas C. Makropoulos  S. Balamir Üçer 《Geophysical Journal International》1984,78(2):475-506

  相似文献   

The Source-Layering Function of Underground Explosions and Earthquakes-an Application of a 'Common Path' Method     

P. D. Marshall  P. W. Burton 《Geophysical Journal International》1971,24(5):533-537

  相似文献   

Extreme Earthquake and Earthquake Perceptibility Study in Greece and its Surrounding Area   总被引：3，自引：0，他引：3  

Burton  Paul W.  Qin  Changyuan  Tselentis  G.-Akis  Sokos  Ethimios 《Natural Hazards》2004,32(3):277-312

The sample interval for the selection of extreme magnitudes plays an important part in the quality of Gumbel model fitting. A short sample interval can produce many observations, which is helpful in obtaining a reliably fitting model. However a short sample interval can bring many dummy ``observations', a condition which adversely biases the fitting. The short sample interval also increases the chance to introduce non-independent observations as well, which violates a basic requirement of the Gumbel model. On the other hand, a large time interval not only reduces the number of observations, but also enlarges the observation error. Thus, for Greece, the most suitable parameters of the third Gumbel extreme model are obtained by using a sample interval which produces minimum error. In consideration of the reliability of the seismic data, earthquakes with magnitude M 5.5 in Greece and its surrounding region after 1900 are used mainly in the present paper. In order to obtain well resolved contour maps with smooth changes a 2°× 2° cell with half-degree overlap strategy was used to scan the region. The most expected largest earthquake for the next fifty, one hundred and two hundred years are estimated for each cell. Likewise, the events with magnitude at a probability of 90\% of non-exceedance over the next fifty, one hundred and two hundred years are estimated for each cell. In parallel to this procedure we also analyze the 67 shallow seismic zones outlined by Papazachos and his colleagues and detail individual zone results where these are obtained. The most perceptible earthquake magnitude for the range of intensities I = {VI}, VII and VIII are also calculated. All results show that the areas around the Hellenic Arc and the Cephalonia Transform Fault for Greece have comparatively high frequency of destructive earthquakes accompanied by a high occurrence probability of moderate earthquakes (M 5.5).  相似文献   

Coastal pollution hazards in southern California observed by SAR imagery: stormwater plumes, wastewater plumes, and natural hydrocarbon seeps     

Digiacomo PM  Washburn L  Holt B  Jones BH 《Marine pollution bulletin》2004,49(11-12):1013-1024

Stormwater runoff plumes, municipal wastewater plumes, and natural hydrocarbon seeps are important pollution hazards for the heavily populated Southern California Bight (SCB). Due to their small size, dynamic and episodic nature, these hazards are difficult to sample adequately using traditional in situ oceanographic methods. Complex coastal circulation and persistent cloud cover can further complicate detection and monitoring of these hazards. We use imagery from space-borne synthetic aperture radar (SAR), complemented by field measurements, to examine these hazards in the SCB. The hazards are detectable in SAR imagery because they deposit surfactants on the sea surface, smoothing capillary and small gravity waves to produce areas of reduced backscatter compared with the surrounding ocean. We suggest that high-resolution SAR, which obtains useful data regardless of darkness or cloud cover, could be an important observational tool for assessment and monitoring of coastal marine pollution hazards in the SCB and other urbanized coastal regions.  相似文献