The production rate of Al 26 from target elements in the Bruderheim chondrite

Computer Science

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

4

Scientific paper

An 840-g specimen of the Bruderheim chondrite was subjected to magnetic and heavy-liquid mineral separation procedures, resulting in a number of chemically distinct samples. These samples were analyzed for cosmogenic Al 26 by non-destructive gamma-gamma coincidence counting. The observed Al 26 specific activities were correlated with the chemical composition of potential target elements by a weighted least-squares fitting technique. The calculated Al 26 production rates, in dpm per kilogram of target element, are: Al, 1130 ± 190; Si, 245 ± 31; S, 133 ± 11; Mg, 28 ± 30. Production rates from Ca and Ni + Fe were estimated to be 24 and 2.2 dpm/kg, respectively, from spallation systematics. Most meteorite classes show a distribution of ( Al 26 ) obs /( Al 26 ) clac , primarily between 0·80 and 1·10 (excluding short exposure age effects). The only exception is the eucrites. The five eucrites with the highest relative Al 26 activities have only 0·77 ± 0·03 of their respective calculated activities. Two Apollo 12 samples, from mean depths of 15-20 cm, have approximately 0·78 of the Al 26 activities calculated for their chemical compositions. A depletion in Al 26 in lunar samples shielded from solar radiation is in accord with a reduced cosmic-ray flux near the earth's orbit, relative to that experienced by most meteorites. The Al 26 depletion in the eucrites suggests that they spent a greater proportion of their orbital periods near 1 AU than have most meteorites. The similarity in relative Al 26 contents of the lunar samples and the eucrites may not be a coincidence.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The production rate of Al 26 from target elements in the Bruderheim chondrite does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The production rate of Al 26 from target elements in the Bruderheim chondrite, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The production rate of Al 26 from target elements in the Bruderheim chondrite will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1728315

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.