Nonthermal X-radiation of SNR RX J1713.7-3946: The Relations to a Nearby Molecular Cloud

The recent X-ray and CO observations of RX J1713.7-3946 show that a significant fraction of the nonthermal X-ray emission of this unique supernova remnant associates, in one way or another, with a molecular cloud interacting with the west part of the shell. This adds a new puzzle in the origin of X-ray emission which cannot be easily explained within the standard model in accordance of which X-rays are result of synchrotron radiation of multi-TeV electrons accelerated by supernova shock waves. We explore an alternative origin of the X-ray emission assuming that it is produced by secondary electrons resulting from high energy hadronic interactions in the molecular gas. Such a scenario could explain in a quite natural way the apparent correlation between the X-ray and CO morphologies. However, the TeV gamma-ray emission recently reported by H.E.S.S. significantly constrains the parameter space of this model. Namely, this mechanism cannot reproduce the bulk of the observed X-ray flux unless one postulates existence of a PeV cosmic-ray component penetrating with an unusually hard spectrum into the dense cloud.Comment: 6 pages, 3 figures, to appear in Proc. of Int. Symp. on High Energy Gamma-ray Astronomy, Heidelberg (July 2004

A definição dos idosos de qualidade de vida

OBJECTIVES: Senescence for some elderly people is a phase of with development and satisfaction, whereas for others is a negative stage of life. The determinants of a good quality of life in old age vary from person to person. The aims of this study were to identify: 1) the prevalence of octogenarian people who evaluate their current life as being mainly characterized by a positive quality and 2) which were the domains that they identified as being the determinants of this positive quality. A same parallel study was conducted with subjects who evaluated senescence as a preponderantly negative experience. METHODS: A random and representative sample of 35% of the octogenarian people, living residing in the community, was selected among the dwellers of the city of Veranópolis, state of Rio Grande do Sul. A semi-structured questionnaire on quality of life quality was applied as well as the scale of depressive symptoms Geriatric Depression Scale (GDS) and the index of general health Cumulative Illness Rating Scale (CIRS). RESULTS: Slightly more than half of the studied sample (57%) defined their current quality of life with positive evaluations, whereas 18% presented a negative evaluation of it. A group 0f 25% defined their current lives as neutral or having both values (positive and negative). Those who were dissatisfied presented more health problems according to the CIRS and more depressive symptoms when evaluated by the GDS. Satisfied subjects ones had different reasons to justify this state, however, the dissatisfied had mainly the lack of health as a reason for their suffering. The main source of reported daily well-being was the involvement with rural or domestic activities. Among the interviewed, lack of health was the main source for not presenting well-being, although there was interpersonal variability regarding what each subject considered as loss of health. CONCLUSION: Possibly, for the elderly subjects a negative quality of life is equivalent to loss of health and a positive life quality is equivalent to a greater range of categories such as activity, income, social life and relationship with the family, categories which differed from subject to subject. Therefore, health seems to be a good indicator of negative quality of life, though an insufficient indicator of successful elderliness.OBJETIVOS: A velhice para alguns é uma etapa de desenvolvimento e satisfação, enquanto para outros é uma fase negativa da vida. Os determinantes da boa qualidade de vida na velhice variam de sujeito para sujeito. O objetivo do presente estudo foi identificar: 1) a prevalência de octagenários que avaliavam sua vida atual na velhice como preponderantemente de uma qualidade positiva e 2) quais aspectos eles identificavam como os determinantes desta qualidade positiva. Igual estudo em paralelo foi feito com sujeitos que avaliavam a velhice como uma experiência preponderantemente negativa. MÉTODOS: Uma amostra randômica e representativa de 35% dos idosos com mais de 80 anos residentes na comunidade foi selecionada entre os residentes em Veranópolis, Rio Grande do Sul. Um questionário semi- estruturado de qualidade de vida foi aplicado, bem como a escala de sintomas depressivos Geriatric Depression Scale (GDS) e o Índice de Saúde Geral Cumulative Illness Rating Scale (CIRS). RESULTADO: Um pouco mais da metade dos idosos estudados (57%) definia sua qualidade de vida atual com avaliações positivas, sendo que 18% tinham uma avaliação negativa da vida atual. Um grupo de 25% definia sua vida atual de forma neutra ou de dois valores (aspectos positivos e aspectos negativos). Comparados com os satisfeitos, os insatisfeitos tinham mais problemas de saúde pela CIRS e mais sintomas depressivos quando avaliados pela GDS. Os satisfeitos tinham diferentes motivos para justificar este estado, porém os insatisfeitos tinham principalmente a falta de saúde física como motivo do sofrimento. A maior fonte de bem estar no dia-a-dia citada era o envolvimento com atividades rurais ou domésticas. Entre os entrevistados, a perda da saúde física era a principal fonte de mal estar, sendo que havia variabilidade interpessoal quanto ao que cada sujeito considerava como perda de saúde. CONCLUSÃO: É possível que para idosos, qualidade negativa de vida seja equivalente a perda de saúde e qualidade de vida positiva seja equivalente a uma pluralidade maior de categorias como atividade, renda, vida social e relação com a família, categorias diferentes de sujeito para sujeito. O aspecto saúde parece assim um bom indicador de qualidade de vida negativa, porém um indicador insuficiente de velhice bem sucedida.Catholic University of the state of Rio Grande do Sul Institute of Geriatrics and Gerontology Geriatric neuropsychiatric ambulatoryWHO PAHO Associated Chronic Degenerating DiseasesFederal University of São Paulo Paulista Medical School Department of PsychiatryPUCRS Medical School Department of PsychiatryUNIFESP, EPM, Department of PsychiatrySciEL

Nuclear structure of 30S and its implications for nucleosynthesis in classical novae

The uncertainty in the 29P(p,gamma)30S reaction rate over the temperature range of 0.1 - 1.3 GK was previously determined to span ~4 orders of magnitude due to the uncertain location of two previously unobserved 3+ and 2+ resonances in the 4.7 - 4.8 MeV excitation region in 30S. Therefore, the abundances of silicon isotopes synthesized in novae, which are relevant for the identification of presolar grains of putative nova origin, were uncertain by a factor of 3. To investigate the level structure of 30S above the proton threshold (4394.9(7) keV), a charged-particle spectroscopy and an in-beam gamma-ray spectroscopy experiments were performed. Differential cross sections of the 32S(p,t)30S reaction were measured at 34.5 MeV. Distorted wave Born approximation calculations were performed to constrain the spin-parity assignments of the observed levels. An energy level scheme was deduced from gamma-gamma coincidence measurements using the 28Si(3He,n-gamma)30S reaction. Spin-parity assignments based on measurements of gamma-ray angular distributions and gamma-gamma directional correlation from oriented nuclei were made for most of the observed levels of 30S. As a result, the resonance energies corresponding to the excited states in 4.5 MeV - 6 MeV region, including the two astrophysically important states predicted previously, are measured with significantly better precision than before. The uncertainty in the rate of the 29P(p,gamma)30S reaction is substantially reduced over the temperature range of interest. Finally, the influence of this rate on the abundance ratios of silicon isotopes synthesized in novae are obtained via 1D hydrodynamic nova simulations.Comment: 22 pages, 12 figure

Electronic structure of periodic curved surfaces -- topological band structure

Electronic band structure for electrons bound on periodic minimal surfaces is differential-geometrically formulated and numerically calculated. We focus on minimal surfaces because they are not only mathematically elegant (with the surface characterized completely in terms of "navels") but represent the topology of real systems such as zeolites and negative-curvature fullerene. The band structure turns out to be primarily determined by the topology of the surface, i.e., how the wavefunction interferes on a multiply-connected surface, so that the bands are little affected by the way in which we confine the electrons on the surface (thin-slab limit or zero thickness from the outset). Another curiosity is that different minimal surfaces connected by the Bonnet transformation (such as Schwarz's P- and D-surfaces) possess one-to-one correspondence in their band energies at Brillouin zone boundaries.Comment: 6 pages, 8 figures, eps files will be sent on request to [email protected]

Star Forming Dense Cloud Cores in the TeV {\gamma}-ray SNR RX J1713.7-3946

RX J1713.7-3946 is one of the TeV {\gamma}-ray supernova remnants (SNRs) emitting synchrotron X rays. The SNR is associated with molecular gas located at ~1 kpc. We made new molecular observations toward the dense cloud cores, peaks A, C and D, in the SNR in the 12CO(J=2-1) and 13CO(J=2-1) transitions at angular resolution of 90". The most intense core in 13CO, peak C, was also mapped in the 12CO(J=4-3) transition at angular resolution of 38". Peak C shows strong signs of active star formation including bipolar outflow and a far-infrared protostellar source and has a steep gradient with a r^{-2.2$\pm$0.4} variation in the average density within radius r. Peak C and the other dense cloud cores are rim-brightened in synchrotron X rays, suggesting that the dense cloud cores are embedded within or on the outer boundary of the SNR shell. This confirms the earlier suggestion that the X rays are physically associated with the molecular gas (Fukui et al. 2003). We present a scenario where the densest molecular core, peak C, survived against the blast wave and is now embedded within the SNR. Numerical simulations of the shock-cloud interaction indicate that a dense clump can indeed survive shock erosion, since shock propagation speed is stalled in the dense clump. Additionally, the shock-cloud interaction induces turbulence and magnetic field amplification around the dense clump that may facilitate particle acceleration in the lower-density inter-clump space leading to the enhanced synchrotron X rays around dense cores.Comment: 22 pages, 7 figures, to accepted in The Astrophysical Journal. A full color version with higher resolution figures is available at http://www.a.phys.nagoya-u.ac.jp/~sano/ApJ10/ms_sano.pd

Phases of one dimensional large N gauge theory in a 1/D expansion

We consider large N Yang Mills theory with D adjoint scalar fields in d dimensions for d=0 or 1. We show the existence of a non-trivial saddle point of the functional integral at large D which is characterized by a mass gap for the adjoint scalars. We integrate out the adjoint scalars in a 1/D expansion around the saddle point. In case of one dimension which is regarded as a circle, this procedure leads to an effective action for the Wilson line. We find an analogue of the confinement/deconfinement transition which consists of a second order phase transition from a uniform to a non-uniform eigenvalue distribution of the Wilson line, closely followed by a Gross-Witten-Wadia transition where a gap develops in the eigenvalue distribution. The phase transition can be regarded as a continuation of a Gregory-Laflamme transition. Our methods involve large values of the dimensionless 'tHooft coupling. The analysis in this paper is quantitatively supported by earlier numerical work for D=9.Comment: 27 pages + 21 pages of Appendix; 8 figures, v2:some comments are added in sec.4.3, minor corrections, one reference added, v3: minor corrections, one reference added, version to be published in JHE

Near- and Far-Infrared Counterparts of Millimeter Dust Cores in the Vela Molecular Ridge Cloud D

The aim of this paper is to identify the young protostellar counterparts associated to dust millimeter cores of the Vela Molecular Ridge Cloud D through new IR observations (H_2 narrow-band at 2.12 micron and N broad band at 10.4 micron) along with an investigation performed on the existing IR catalogues. The association of mm continuum emission with infrared sources from catalogues (IRAS, MSX, 2MASS), JHK data from the literature and new observations, has been established according to spatial coincidence, infrared colours and spectral energy distributions. Only 7 out of 29 resolved mm cores (and 16 out of the 26 unresolved ones) do not exhibit signposts of star formation activity. The other ones are clearly associated with: far-IR sources, H_2 jets or near-IR objects showing a high intrinsic colour excess. The distribution of the spectral indices pertaining to the associated sources is peaked at values typical of Class I objects, while three objects are signalled as candidates Class 0 sources. We remark the high detection rate (30%) of H_2 jets driven by sources located inside the mm-cores. They appear not driven by the most luminous objects in the field, but rather by less luminous objects in young clusters, testifying the co-existence of both low- and intermediate-mass star formation. The presented results reliably describe the young population of VMR-D. However, the statistical evaluation of activity vs inactivity of the investigated cores, even in good agreement with results found for other star forming regions, seems to reflect the limiting sensitivity of the available facilities rather than any property intrinsic to the mm-condensations.Comment: 38 pages. To be published to Astronomy & Astrophysic

Enhanced Ionic Conductivity of Monovalent Cation Halide (AgBr, AgI, LiI) in Mesoporous Alumina

Monovalent ionic conductors (AgI, AgBr and LiI) impregnated in mesoporous alumina were studied in the context of heterogeneous ionic conductors. The crystalline structure and local structure of the ionic conductors were investigated by XRD, DSC and NMR. Enhancement of ionic conductivity strongly depended on the ionic conductors, which was attributed to local structure as well as space charge layer.Nagasaki Symposium on Nano-Dynamics 2008 (NSND2008) 平成20年1月29日(火)於長崎大学 Poster Presentatio