Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 114
Filtrar
1.
Phys Rev Lett ; 127(13): 139902, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34623869

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.114.082501.

2.
Phys Rev Lett ; 124(2): 022501, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-32004026

RESUMO

Spectroscopic factors of neutron-hole and proton-hole states in ^{131}Sn and ^{131}In, respectively, were measured using one-nucleon removal reactions from doubly magic ^{132}Sn at relativistic energies. For ^{131}In, a 2910(50)-keV γ ray was observed for the first time and tentatively assigned to a decay from a 5/2^{-} state at 3275(50) keV to the known 1/2^{-} level at 365 keV. The spectroscopic factors determined for this new excited state and three other single-hole states provide first evidence for a strong fragmentation of single-hole strength in ^{131}Sn and ^{131}In. The experimental results are compared to theoretical calculations based on the relativistic particle-vibration coupling model and to experimental information for single-hole states in the stable doubly magic nucleus ^{208}Pb.

3.
Phys Rev Lett ; 124(5): 052501, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32083900

RESUMO

The rare phenomenon of nuclear wobbling motion has been investigated in the nucleus ^{187}Au. A longitudinal wobbling-bands pair has been identified and clearly distinguished from the associated signature-partner band on the basis of angular distribution measurements. Theoretical calculations in the framework of the particle rotor model are found to agree well with the experimental observations. This is the first experimental evidence for longitudinal wobbling bands where the expected signature partner band has also been identified, and establishes this exotic collective mode as a general phenomenon over the nuclear chart.

4.
J Parasit Dis ; 42(1): 19-21, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29491553

RESUMO

A total of 445 faecal samples and 128 rumens of sheep collected from Slaughter house, Mhow (Madhya Pradesh) were examined for a period of 1 year from February 2011 to January 2012. Faecal sample examination based, incidence of amphistomes was found to be 23.37% from the study area. The incidence of amphistomes was significantly higher (p < 0.01) during summer (36.75%) than winter (27.74%) and monsoon (3.52%). Age-wise, non-significantly higher infection was observed in ≥1 year-old animals (23.61%) than <1 year-old animals (23.11%). Non-significantly higher rate of infection was recorded in case of females (25.63%) than that of males (19.64%). Out of 128, 49 (38.28%) rumens were found positive for amphistomes. The prevalence of Paramphistomum cervi (27.34%) was found to be significantly (p < 0.01) higher than Gastrothylax crumenifer (10.94%).

5.
Phys Rev Lett ; 118(17): 172501, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28498679

RESUMO

The (^{10}Be,^{10}B^{*}[1.74 MeV]) charge-exchange reaction at 100 AMeV is presented as a new probe for isolating the isovector (ΔT=1) nonspin-transfer (ΔS=0) response of nuclei, with ^{28}Si being the first nucleus studied. By using a secondary ^{10}Be beam produced by fast fragmentation of ^{18}O nuclei at the NSCL Coupled Cyclotron Facility, applying the dispersion-matching technique with the S800 magnetic spectrometer to determine the excitation energy in ^{28}Al, and performing high-resolution γ-ray tracking with the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) to identify the 1022-keV γ ray associated with the decay from the 1.74-MeV T=1 isobaric analog state in ^{10}B, a ΔS=0 excitation-energy spectrum in ^{28}Al was extracted. Monopole and dipole contributions were determined through a multipole-decomposition analysis, and the isovector giant dipole resonance and isovector giant monopole resonance (IVGMR) were identified. The results show that this probe is a powerful tool for studying the elusive IVGMR, which is of interest for performing stringent tests of modern density functional theories at high excitation energies and for constraining the bulk properties of nuclei and nuclear matter. The extracted distributions were compared with theoretical calculations based on the normal-modes formalism and the proton-neutron relativistic time-blocking approximation. Calculated cross sections based on these strengths underestimate the data by about a factor of 2, which likely indicates deficiencies in the reaction calculations based on the distorted wave Born approximation.

6.
West Indian Med J ; 64(4): 456-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26624607
7.
Phys Rev Lett ; 114(8): 082501, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25768759

RESUMO

A pair of transverse wobbling bands is observed in the nucleus ^{135}Pr. The wobbling is characterized by ΔI=1, E2 transitions between the bands, and a decrease in the wobbling energy confirms its transverse nature. Additionally, a transition from transverse wobbling to a three-quasiparticle band comprised of strong magnetic dipole transitions is observed. These observations conform well to results from calculations with the tilted axis cranking model and the quasiparticle rotor model.

8.
Phys Rev Lett ; 113(3): 032504, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25083638

RESUMO

The isoscalar monopole response has been measured in the unstable nucleus (68)Ni using inelastic alpha scattering at 50A MeV in inverse kinematics with the active target MAYA at GANIL. The isoscalar giant monopole resonance (ISGMR) centroid was determined to be 21.1 ± 1.9 MeV and indications for a soft monopole mode are provided for the first time at 12.9 ± 1.0 MeV. Analysis of the corresponding angular distributions using distorted-wave-born approximation with random-phase approximation transition densities indicates that the L = 0 multipolarity dominates the cross section for the ISGMR and significantly contributes to the low-energy mode. The L=0 part of this low-energy mode, the soft monopole mode, is dominated by neutron excitations. This demonstrates the relevance of inelastic alpha scattering in inverse kinematics in order to probe both the ISGMR and isoscalar soft modes in neutron-rich nuclei.

9.
Mens Sana Monogr ; 12(1): 71-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24891798

RESUMO

We live in a world that is increasingly complex, intense, and stressful. Most people, at some time or other in their lives, can make good use of psychiatry as they map their course and steer their way through it. While this holds true, there also exists a very disturbing trend. No other branch of medicine suffers a similar, constant criticism, scrutiny and quite often downright vehement protest. Even the service users, who have been greatly benefitted, choose to stay mum for fear of stigmatization that may follow if they admit to have undergone therapy. The onus lies on both, the service users and providers alike, to take the positive contributions of psychiatry to the masses at large. All of us, especially medical professionals, need to consider our own attitudes and awareness. The recognition that anyone will break down if mental stress is high enough should help free us from a 'them and us' attitude. Reading about people's own experience of mental illness can promote understanding: Examples include a successful actress and a prize-winning author. For mental health practitioners, enabling service users to influence service development is another strong anti-stigma move. A cognitive behavior therapy approach can help individuals overcome the stigma felt and also cope better with discrimination. Also, we need to stand up against mental health discrimination wherever it is encountered.

10.
Phys Rev Lett ; 112(11): 112503, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24702356

RESUMO

Excited states in the neutron-rich N = 38, 36 nuclei (60)Ti and (58)Ti were populated in nucleon-removal reactions from (61)V projectiles at 90 MeV/nucleon. The γ-ray transitions from such states in these Ti isotopes were detected with the advanced γ-ray tracking array GRETINA and were corrected event by event for large Doppler shifts (v/c ∼ 0.4) using the γ-ray interaction points deduced from online signal decomposition. The new data indicate that a steep decrease in quadrupole collectivity occurs when moving from neutron-rich N = 36, 38 Fe and Cr toward the Ti and Ca isotones. In fact, (58,60)Ti provide some of the most neutron-rich benchmarks accessible today for calculations attempting to determine the structure of the potentially doubly magic nucleus (60)Ca.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA