Properties of the energetic particle distributions during the October 28, 2003 solar flare from INTEGRAL/SPI observations

Analysis of spectra obtained with the gamma-ray spectrometer SPI onboard INTEGRAL of the GOES X17-class flare on October 28, 2003 is presented. In the energy range 600 keV - 8 MeV three prominent narrow lines at 2.223, 4.4 and 6.1 MeV, resulting from nuclear interactions of accelerated ions within the solar atmosphere could be observed. Time profiles of the three lines and the underlying continuum indicate distinct phases with several emission peaks and varying continuum-to-line ratio for several minutes before a smoother decay phase sets in. Due to the high-resolution Ge detectors of SPI and the exceptional intensity of the flare, detailed studies of the 4.4 and 6.1 MeV line shapes was possible for the first time. Comparison with calculated line shapes using a thick target interaction model and several energetic particle angular distributions indicates that the nuclear interactions were induced by downward-directed particle beams with alpha-to-proton ratios of the order of 0.1. There are also indications that the 4.4 MeV to 6.1 MeV line fluence ratio changed between the beginning and the decay phase of the flare, possibly due to a temporal evolution of the energetic particle alpha-to-proton ratio.Comment: 24 pages, 10 figures, accepted for publication by A&

Caught in a ‘spiral’. Barriers to healthy eating and dietary health promotion needs from the perspective of unemployed young people and their service providers

NoThe number of young people in Europe who are not in education, employment or training (NEET) is increasing. Given that young people from disadvantaged backgrounds tend to have diets of poor nutritional quality, this exploratory study sought to understand barriers and facilitators to healthy eating and dietary health promotion needs of unemployed young people aged 16–20 years. Three focus group discussions were held with young people (n = 14). Six individual interviews and one paired interview with service providers (n = 7). Data were recorded, transcribed verbatim and thematically content analysed. Themes were then fitted to social cognitive theory (SCT). Despite understanding of the principles of healthy eating, a ‘spiral’ of interrelated social, economic and associated psychological problems was perceived to render food and health of little value and low priority for the young people. The story related by the young people and corroborated by the service providers was of a lack of personal and vicarious experience with food. The proliferation and proximity of fast food outlets and the high perceived cost of ‘healthy’ compared to ‘junk’ food rendered the young people low in self-efficacy and perceived control to make healthier food choices. Agency was instead expressed through consumption of junk food and drugs. Both the young people and service providers agreed that for dietary health promotion efforts to succeed, social problems needed to be addressed and agency encouraged through (individual and collective) active engagement of the young people themselves

Capabilities of GRO/OSSE for observing solar flares

The launch of the Gamma Ray Observatory (GRO) near solar maximum makes solar flare studies early in the mission particularly advantageous. The Oriented Scintillation Spectrometer Experiment (OSSE) on GRO, covering the energy range 0.05 to 150 MeV, has some significant advantages over the previous generation of satellite-borne gamma-ray detectors for solar observations. The OSSE detectors will have about 10 times the effective area of the Gamma-Ray Spectrometer (GRS) on Solar Maximum Mission (SMM) for both photons and high-energy neutrons. The OSSE also has the added capability of distinguishing between high-energy neutrons and photons directly. The OSSE spectral accumulation time (approx. 4s) is four times faster than that of the SMM/GRS; much better time resolution is available in selected energy ranges. These characteristics will allow the investigation of particle acceleration in flares based on the evolution of the continuum and nuclear line components of flare spectra, nuclear emission in small flares, the anisotropy of continuum emission in small flares, and the relative intensities of different nuclear lines. The OSSE observational program will be devoted primarily to non-solar sources. Therefore, solar observations require planning and special configurations. The instrumental and operational characteristics of OSSE are discussed in the context of undertaking solar observations. The opportunities for guest investigators to participate in solar flare studies with OSSE is also presented

Correlates of food choice in unemployed young people: The role of demographic factors, self-efficacy, food involvement, food poverty and physical activity.

yesAssociations between socio-demographic and psychological factors and food choice patterns were explored in unemployed young people who constitute a vulnerable group at risk of poor dietary health. Volunteers (N = 168), male (n = 97) and female (n = 71), aged 15–25 years were recruited through United Kingdom (UK) community-based organisations serving young people not in education training or employment (NEET). Survey questionnaire enquired on food poverty, physical activity and measured responses to the Food Involvement Scale (FIS), Food Self-Efficacy Scale (FSS) and a 19-item Food Frequency Questionnaire (FFQ). A path analysis was undertaken to explore associations between age, gender, food poverty, age at leaving school, food self-efficacy (FS-E), food involvement (FI) (kitchen; uninvolved; enjoyment), physical activity and the four food choice patterns (junk food; healthy; fast food; high fat). FS-E was strong in the model and increased with age. FS-E was positively associated with more frequent choice of healthy food and less frequent junk or high fat food (having controlled for age, gender and age at leaving school). FI (kitchen and enjoyment) increased with age. Higher FI (kitchen) was associated with less frequent junk food and fast food choice. Being uninvolved with food was associated with more frequent fast food choice. Those who left school after the age of 16 years reported more frequent physical activity. Of the indirect effects, younger individuals had lower FI (kitchen) which led to frequent junk and fast food choice. Females who were older had higher FI (enjoyment) which led to less frequent fast food choice. Those who had left school before the age of 16 had low food involvement (uninvolved) which led to frequent junk food choice. Multiple indices implied that data were a good fit to the model which indicated a need to enhance food self-efficacy and encourage food involvement in order to improve dietary health among these disadvantaged young people

Search for Gamma-Ray Transients using the SMM Spectrometer

Observations for transient radiation made by the Gamma Ray Spectrometer on the SMM satellite are summarized. Spectra were obtained from 215 solar flares and 177 gamma-ray bursts. No narrow or moderately broadened lines were observed in any of the bursts. The rate of bursts is consistent with a constant over the mission but is weakly correlated with solar activity. No evidence was found for bursts of 511 keV line emission, unaccompanied by a strong continuum, at levels not less than 0.05 gamma/sq cm s for bursts lasting not more than 16 s. No evidence was found for broad features near 1 MeV from Cyg X-1, the Galactic center, or the Crab in 12-d integrations at levels not less than 0.006 gamma/sq cm s. No evidence was found for transient celestial narrow-line emission from 300 keV to 7 MeV on min-to-hrs-long time scales from 1984 to 1989

SMM Observations of Gamma-Ray Transients. I. A Search for Variable Emission at MeV Energies from Five Galactic and Extragalactic Sources

Transient emission at energies near 1 MeV has been reported by previous experiments on time scales of weeks to months from the Galactic center, the Crab Nebula, and Cyg X-1, and on shorter time-scales from NGC 4151 and Cen A. The spectra of these events fall into two broad classes: a broad line-like feature centered near 1 MeV, and continuum emission (or a very broad feature) extending from ˜600 keV up to several MeV. These features have been interpreted theoretically in terms of emission from hot pair-dominated plasmas, which may be the necessary positron source implied by reports of narrow e- e+ annihilation lines from Cyg X- 1 and the Galactic center. In this paper, data accumulated by the Solar Maximum Mission Gamma Ray Spectrometer (GRS) between 1980 and 1989 have been searched for evidence of these two types of features. We find no compelling evidence for transient 1 MeV broad-line emission on time scales of order 12 d or longer when any of the sources are in the GRS field of view; upper limits on the transient line flux during any 12 d period are typically ˜4.5 × 10-3gamma (cm2 s)-1. The same is true of variability of the continuum between 0.6-7 MeV, for which the upper limits are characteristically ˜2 times the nominal flux from the Crab for any 12 d period. Our analysis was not sensitive enough either to confirm or to reject several reports from other experiments of transient emission in the 0.6-7 MeV continuum during 1980-1989. We withdraw the statement in Share et al. (1993) that our upper limit for one such event, a transient from the Crab Nebula in 1980 Spring, is inconsistent with the measurement of Ling & Dermer (1991). We did not detect any transient emission in the 1 MeV feature preceding or coinciding with reported emission of the 0.511 MeV annihilation line from the Galactic center in 1988-1989. We discuss briefly the implications of this result for models of the annihilation of positrons produced in the Galactic center source 1E 1740.7-2942

Operation and performance of the OSSE instrument

The Oriented Scintillation Spectrometer Experiment (OSSE) on the Arthur Holly Compton Gamma Ray Observatory is described. An overview of the operation and control of the instrument is given, together with a discussion of typical observing strategies used with OSSE and basic data types produced by the instrument. Some performance measures for the instrument are presented that were obtained from pre-launch and in-flight data. These include observing statistics, continuum and line sensitivity, and detector effective area and gain stability

Orthographic facilitation in oral vocabulary acquisition

An experiment investigated whether exposure to orthography facilitates oral vocabulary learning. A total of 58 typically developing children aged 8-9 years were taught 12 nonwords. Children were trained to associate novel phonological forms with pictures of novel objects. Pictures were used as referents to represent novel word meanings. For half of the nonwords children were additionally exposed to orthography, although they were not alerted to its presence, nor were they instructed to use it. After this training phase a nonword-picture matching posttest was used to assess learning of nonword meaning, and a spelling posttest was used to assess learning of nonword orthography. Children showed robust learning for novel spelling patterns after incidental exposure to orthography. Further, we observed stronger learning for nonword-referent pairings trained with orthography. The degree of orthographic facilitation observed in posttests was related to children's reading levels, with more advanced readers showing more benefit from the presence of orthography

Measurement of the 0.3-8.5 MeV Galactic Gamma-Ray Spectrum from the Galactic Center Direction

The low-energy gamma-ray spectrum from the direction of the Galactic center is determined using data obtained with the SMM Gamma-Ray Spectrometer. It is found that the diffuse gamma-ray spectrum from the Galactic center region can be interpreted in a straightforward way as the sum of five components of a presented equation. The components include a hard power law dominating the continuum at high energies caused principally by cosmic ray electron bremsstrahlung radiation, two narrow lines due to Al-26 decay and positron annihilation, an excess continuum component below 0.511 MeV consistent with the annihilation of positrons by formation of Ps, and a soft power law at low energies which is consistent with an extrapolation upward in energy of known hard X-ray sources in the Galactic center region