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P.T. Timbie G.S. Tucker P.A.R. Ade S. Ali E. Bierman E.F. Bunn C. Calderon A.C. Gault P.O. Hyland B.G. Keating J. Kim A. Korotkov S.S. Malu P. Mauskopf J.A. Murphy C. OSullivan L. Piccirillo B.D. Wandelt 《New Astronomy Reviews》2006,50(11-12):999
We provide an overview of a mission concept study underway for the Einstein Inflation Probe (EIP). Our study investigates the advantages and tradeoffs of using an interferometer (EPIC) for the mission. We also report on the status of the millimeter-wave bolometric interferometer (MBI), a ground-based pathfinder optimized for degree-scale CMB polarization measurements at 90 GHz. 相似文献
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Eugene P. Gurov Christian Koeberl Anatoly Yamnichenko 《Meteoritics & planetary science》2007,42(3):307-319
Abstract— The 3.6 Myr old El'gygytgyn impact crater is located in central Chukotka, northeastern Russia. The crater is a well‐preserved impact structure with an inner basin about 15 km in diameter, surrounded by an uplifted rim about 18 km in diameter. The flat floor of the crater is in part occupied by Lake El'gygytgyn, 12 km in diameter, and surrounding terraces. The average profile of the rim is asymmetric, with a steep inner wall and a gentle outer flank. The rim height is about 180 m above the lake level and 140 m above the surrounding area. An outer ring feature, on average 14 m high, occurs at about 1.75 crater radii from the center of the structure. El'gygytgyn crater is surrounded by a complex network of faults. The density of the faults decreases from the bottom of the rim to the rim crest and outside the crater to a distance of about 2.7 crater radii. Lake El'gygytgyn is surrounded by a number of lacustrine terraces. Only minor remnants are preserved of the highest terraces, 80 and 60 m above the present‐day lake level. The widest of the terraces is 40 m above the current lake level and surrounds the lake on the west and northwest sides. The only outlet of the lake is the Enmivaam River, which cuts through the crater rim in the southeast. In terms of structure, El'gygytgyn is well preserved and displays some interesting, but not well understood, features (e.g., an outer ring), similar to those observed at a few other impact structures. 相似文献
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M. Bowden A. N. Taylor K. M. Ganga P. A. R. Ade J. J. Bock G. Cahill J. E. Carlstrom S. E. Church W. K. Gear J. R. Hinderks W. Hu B. G. Keating J. Kovac A. E. Lange E. M. Leitch B. Maffei O. E. Mallie S. J. Melhuish J. A. Murphy G. Pisano L. Piccirillo C. Pryke B. A. Rusholme C. O'Sullivan K. Thompson 《Monthly notices of the Royal Astronomical Society》2004,349(1):321-335
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John K. Webb Michael T. Murphy Victor V. Flambaum Stephen J. Curran 《Astrophysics and Space Science》2003,283(4):565-575
We report results from a third sample of quasar absorption line spectra from the Keck telescope which has been studied to
search for any possible variation of the fine structure constant, α. This third sample, which is larger than the sum of the
two previously published samples, shows the same effect, and also gives, as do the previous two samples, a significant result.
The combined sample yields a highly significant effect, Δα = (αz - α0 )/α0 = -0.57 ± 0.10 × 10-5, averaged over the redshift range 0.2 < z < 3.7. We include a brief discussion of small-scale kinematic structure in quasar
absorbing clouds. However, kinematics are unlikely to impact significantly on the averagednon-zeroΔα /α above, and we have
so far been unable to identify any systematic effect which can explain it. New measurements of quasar spectra obtained using
independent instrumentation and telescopes are required to properly check the Keck results.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献