1. |
- Keller, H., et al.
(författare)
-
Search for Forbidden Beta-Decays of the Drip-Line Nucleus Be-12
- 1994
-
Ingår i: Zeitschrift fur Physik A Hadrons and Nuclei. - 1431-5831 .- 0939-7922. ; 348:1, s. 61-62
-
Tidskriftsartikel (refereegranskat)abstract
- Beta-coincident gamma-rays have been measured from implanted pure samples of Be-12 separated at the LISE3 spectrometer at GANIL. An intensity of 0.040(26)% can be estimated for the branching ratio of the isospin forbidden pure-Fermi transition to the 0+ excited state of B-12 and of 0.008(6) % of the transition to the 1- excited state. Both are taken to represent upper limits. The halflife has been re-measured to be 26.1(2.4) ms.
|
|
2. |
- Anne, R., et al.
(författare)
-
Dissociation Reactions of the Be-11 One-Neutron Halo - the Interplay between Structure and Reaction-Mechanism
- 1993
-
Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 304:1-2, s. 55-59
-
Tidskriftsartikel (refereegranskat)abstract
- The angular distributions of the forward neutrons in the exclusive (Be-10 + n) channel have been measured. They can be accounted for quantitatively and without free parameters in terms of Coulomb and diffraction dissociation. The results show that the transverse momentum distributions result from an interplay between the tail of the wave function (the halo) and the reaction mechanism.
|
|
3. |
- Anne, R., et al.
(författare)
-
Exclusive and Restricted-Inclusive Reactions Involving the Be-11 One-Neutron Halo
- 1994
-
Ingår i: Nuclear Physics A. - : Elsevier BV. - 0375-9474. ; 575:1, s. 125-154
-
Tidskriftsartikel (refereegranskat)abstract
- Reactions of a 41 MeV/u beam of the radioactive halo nucleus Be-11 have been studied with a counter telescope coupled to an array of neutron detectors covering angles up to 97-degrees. The technique allows to determine single-neutron inclusive and exclusive angular distributions. The targets (Be, Ti and Au) were chosen to illustrate the relative roles played by nuclear and Coulomb mechanisms. The channels leading to Be-10, the dissociation channels, correspond to impact parameters larger than the sum of the radii of the target and the Be-10 core. It is shown that for the dissociation process it is possible to account almost quantitatively for the integral, single- and double-differential cross sections from models without free parameters including the Coulomb, Serber and Glauber (diffraction-dissociation) mechanisms. The neutron distributions from the nondissociative reaction channels show little individuality and it is convenient to group them together as the channel ''neutron plus anything different from Be-10''. We refer to these as ''restricted-inclusive'' reactions. These seem to be a promising tool for obtaining accurate information on the halo wave function in momentum coordinates.
|
|
4. |
- Christensson, A, et al.
(författare)
-
Serum prostate specific antigen complexed to alpha 1-antichymotrypsin as an indicator of prostate cancer
- 1993
-
Ingår i: Journal of Urology. - 1527-3792. ; 150:1, s. 100-105
-
Tidskriftsartikel (refereegranskat)abstract
- Prostate specific antigen (PSA) in serum has recently been shown to occur in complex with alpha 1-antichymotrypsin and as an approximately 30 kDa. noncomplexed molecular form. We characterized PSA by 3 different assays in samples from 144 patients with benign prostatic hyperplasia (BPH) and 121 with carcinoma of the prostate. One of these noncompetitive assays measured total PSA by detecting PSA complexed to serine proteinase inhibitors and the noncomplexed molecular form, a second measured only PSA in complex with alpha 1-antichymotrypsin, whereas a third detected the noncomplexed form. PSA in complex with alpha 1-antichymotrypsin was the predominant form in all patient sera. Noncomplexed PSA constituted a minor fraction that was significantly smaller in patients with untreated prostate cancer than in those with BPH (p < 0.0001). The proportion of noncomplexed PSA does not correlate to the serum concentration of PSA or that of alpha 1-antichymotrypsin. In men with a serum PSA concentration of less than 10 micrograms./l. the combination of assays measuring total PSA immunoreactivity, the noncomplexed molecular form and PSA in complex with alpha 1-antichymotrypsin may facilitate discrimination between prostate cancer and BPH.
|
|
5. |
- Tengblad, O., et al.
(författare)
-
Study of Neutron Rich Neon Isotopes
- 1992
-
Ingår i: Zeitschrift fur Physik A Hadrons and Nuclei. - 1431-5831 .- 0939-7922. ; 342:3, s. 303-307
-
Tidskriftsartikel (refereegranskat)abstract
- The half-lives and P(n)-values of the neutron rich isotopes Ne-26-29 have been determined. The results are compared to shell-model calculations and good agreement is found except for Ne-29, where the half-life exceeds the predictions by more than an order of magnitude. This unexpectedly long half-life can be explained as due to a fp intruder configuration.
|
|
6. |
|
|
7. |
- Bergqvist, D, et al.
(författare)
-
Thromboprophylaxis in emergency surgery
- 1993
-
Ingår i: Haemostasis. - 0301-0147. ; 23:Suppl. 1, s. 51-56
-
Tidskriftsartikel (refereegranskat)abstract
- Except for hip fracture surgery, emergency surgery has been only exceptionally studied concerning thromboprophylaxis. There are, however, several reasons to believe the frequency to be fairly high and that the patient group would be in need of prophylaxis. This paper discusses various emergency situations and also gives the design for an ongoing controlled study on the effect of postoperative start of thromboprophylaxis with low molecular weight heparin in emergency abdominal surgery.
|
|
8. |
- Borge, M. J. G., et al.
(författare)
-
Super-Allowed Beta-Decay of Nuclei at the Drip-Line
- 1991
-
Ingår i: Zeitschrift fur Physik A Hadrons and Nuclei. - 1431-5831 .- 0939-7922. ; 340:3, s. 255-261
-
Tidskriftsartikel (refereegranskat)abstract
- We have investigated the continuous particle spectra following the beta decay of the neutron-rich nuclei that terminate the mass 6, 8, 9 and 11 isobaric chains. Strong beta transitions feeding the very top of the spectrum are found systematically. The favoured states are within a few MeV of the energy of the initial state. This phenomenon seems to be linked to the occurrence of a di-neutron structure or neutron halo in the drip-line nuclei.
|
|
9. |
- Cronqvist, M., et al.
(författare)
-
Experimental-Determination of Cross-Talk between Neutron Detectors
- 1992
-
Ingår i: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - 0168-9002. ; 317:1-2, s. 273-280
-
Tidskriftsartikel (refereegranskat)abstract
- Neutron cross-talk measurements have been performed with 14.1 MeV neutrons for organic scintillator detectors with n-gamma discrimination capability. The probability for cross-talk between two 156 mm thick neutron detectors with a hexagonal cross section (effective diameter 167 mm) placed 0.33 m apart was found to be (2.5+/-1.1) 10(-4). A similar measurement between two 100 mm thick, cylindrically shaped detectors with 50 mm diameter and at 75 mm distance from each other yielded a cross-talk probability of (2.5+/-0.4) 10(-3). The measured cross-talk probabilities are in agreement with values from a Monte Carlo calculation.
|
|