Developments in spin-polarized internal targets for storage rings have permitted measurements of 197 MeV polarized protons scattering from vector polarized deuterons. This work presents measurements ...of the polarization observables A(y), iT11, and C(y,y) in proton-deuteron elastic scattering. When compared to calculations with and without three-nucleon forces, the measurements provide further evidence that three-nucleon forces make a contribution to the observables. This work indicates that three-body forces derived from static nuclear properties appear to be crucial to the description of dynamical properties.
The STAR endcap electromagnetic calorimeter Allgower, C.E.; Anderson, B.D.; Baldwin, A.R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2003, Letnik:
499, Številka:
2
Journal Article
Recenzirano
The STAR endcap electromagnetic calorimeter will provide full azimuthal coverage for high-
p
T photons, electrons and electromagnetically decaying mesons over the pseudorapidity range 1.086⩽
η⩽2.00. ...It includes a scintillating-strip shower-maximum detector to provide π
0/γ discrimination and preshower and postshower layers to aid in distinguishing between electrons and charged hadrons. The triggering capabilities and coverage it offers are crucial for much of the spin physics program to be carried out in polarized proton–proton collisions.
The first measurements of the d(gamma,p)n differential cross section at forward angles and photon energies above 4 GeV were performed at the Thomas Jefferson National Accelerator Facility (JLab). The ...results indicate evidence of an angular dependent scaling threshold. Results at straight theta(cm) = 37 degrees are consistent with the constituent counting rules for E(gamma) greater, similar 4 GeV, while those at 70 degrees are consistent with the constituent counting rules for E(gamma) greater, similar 1.5 GeV.
Azimuthal anisotropy (v(2)) and two-particle angular correlations of high p(T) charged hadrons have been measured in Au+Au collisions at sqrts(NN)=130 GeV for transverse momenta up to 6 GeV/c, where ...hard processes are expected to contribute significantly. The two-particle angular correlations exhibit elliptic flow and a structure suggestive of fragmentation of high p(T) partons. The monotonic rise of v(2)(p(T)) for p(T)<2 GeV/c is consistent with collective hydrodynamical flow calculations. At p(T)>3 GeV/c, a saturation of v(2) is observed which persists up to p(T)=6 GeV/c.
The STAR Collaboration reports the first observation of exclusive rho(0) photoproduction, AuAu-->AuAurho(0), and rho(0) production accompanied by mutual nuclear Coulomb excitation, ...AuAu-->Au*Au*rho(0), in ultraperipheral heavy-ion collisions. The rho(0) have low transverse momenta, consistent with coherent coupling to both nuclei. The cross sections at sqrts(NN)=130 GeV agree with theoretical predictions treating rho(0) production and Coulomb excitation as independent processes.
ABSTRACT
We report on the detailed characterization of the HD 77946 planetary system. HD 77946 is an F5 (M* = 1.17 M⊙, R* = 1.31 R⊙) star, which hosts a transiting planet recently discovered by ...NASA’s Transiting Exoplanet Survey Satellite (TESS), classified as TOI-1778 b. Using TESS photometry, high-resolution spectroscopic data from HARPS-N, and photometry from CHEOPS, we measure the radius and mass from the transit and radial velocity observations, and find that the planet, HD 77946 b, orbits with period Pb = $6.527282_{-0.000020}^{+0.000015}$ d, has a mass of Mb = 8.38 ± 1.32 M⊕, and a radius of $R_{\rm b} = 2.705_{-0.081}^{+0.086}$R⊕. From the combination of mass and radius measurements, and the stellar chemical composition, the planet properties suggest that HD 77946 b is a sub-Neptune with a ∼1 per cent H/He atmosphere. However, a degeneracy still exists between water-world and silicate/iron-hydrogen models, and even though interior structure modelling of this planet favours a sub-Neptune with a H/He layer that makes up a significant fraction of its radius, a water-world composition cannot be ruled out, as with $T_{\rm eq}~= 1248^{+40}_{-38}~$K, water may be in a supercritical state. The characterization of HD 77946 b, adding to the small sample of well-characterized sub-Neptunes, is an important step forwards on our journey to understanding planetary formation and evolution pathways. Furthermore, HD 77946 b has one of the highest transmission spectroscopic metrics for small planets orbiting hot stars, thus transmission spectroscopy of this key planet could prove vital for constraining the compositional confusion that currently surrounds small exoplanets.
Clinical visits (work experience opportunities) are a recommended part of admissions processes for many diagnostic and therapeutic radiography courses but not for operating department practice (ODP) ...where observational visits are challenging for applicants to obtain. The Covid-19 pandemic interrupted access to visits for all prospective students; this study presents a review of the value of clinical visits and alternatives.
This article reports the initial qualitative phase of a three-phase mixed methods study. Using a critical realist approach, focus groups explored first year student experiences of the ‘ideal’ pre-admission clinical visit and alternative resources. A structured review of Online Prospectus (OLP) entries was undertaken by two student researchers to ascertain the requirements for clinical visits for the three professions.
Four focus groups included 25 first year students interviewed prior to their first clinical placement (14 therapeutic radiography, 5 diagnostic radiography and 6 ODP students). Three themes were constructed, namely: informing career choices, the clinical visit experience, and the value of clinical visits. Clinical visits affirmed rather than inspired career choices. The best timing for a visit was before admission interviews and optimal duration was a full day. Interacting with current students was the most valued aspect. Videos and simulations provided in-depth information about the professional role and allowed replay, but some participants found the videos uninspiring. OLP entries present a confusing picture for applicants who may be researching several Universities and professions.
Clinical visits were deemed ‘vital’ to radiography student career choices, yet ODPs who could not access visits were comfortable with videos. Simulated visits are a safe option amidst the pandemic but must capture the dynamic and patient-centred nature of practice to accurately inform career choices.
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