Gamma ray emission from the region of the galactic center

A combination nuclear emulsion-spark chamber gamma ray (E=100 MeV) telescope was used to study the region of sky that includes the Galactic Center. 95% confidence upper limits on the flux from the reported sources G gamma 2 - 3 and Sgr gamma-1 were placed at 4.4 and 8.8 x 10 to the minus 5th power protons/sq cm-sec, and a similar limit on the emission from the Galactic Center as a point source (plus or minus .75 degrees) was placed at 3.3 x 10 to the minus 5th power protons/sq cm-sec. No enhanced emission was observed from the Galactic Plane (plus or minus 6 degrees) and an upper limit of 2 x 10 to the minus 4th power protons/sq cm-sec rad/ was obtained

NICMOS Imaging of the Dusty Microjansky Radio Source VLA J123642+621331 at z = 4.424

We present the discovery of a radio galaxy at a likely redshift of z = 4.424 in one of the flanking fields of the Hubble Deep Field. Radio observations with the VLA and MERLIN centered on the HDF yielded a complete sample of microjansky radio sources, of which about 20% have no optical counterpart to I < 25 mag. In this Letter, we address the possible nature of one of these sources, through deep HST NICMOS images in the F110W (J) and F160W (H) filters. VLA J123642+621331 has a single emission line at 6595-A, which we identify with Lyman-alpha at z = 4.424. We argue that this faint (H = 23.9 mag), compact (r = 0.2 arcsec), red (I - K = 2.0) object is most likely a dusty, star-forming galaxy with an embedded active nucleus.Comment: Accepted for publication in Astrophysical Journal Letters. 11 pages, 4 figures, uses aastex v5.0 and psfi

Community-driven development: does it build social cohesion or infrastructure? A mixed-method evidence synthesis

This paper synthesises evidence on 23 communitydriven development programmes. It combines narrative synthesis and meta-analysis to examine the impact of these programmes along their causal chain. It summarises the main findings of a longer technical report available on the 3ie website. The content of this paper is the sole responsibility of the authors and does not represent the opinions of 3ie, its donors or its board of commissioners. Any errors and omissions are also the sole responsibility of the authors. Please direct any comments or queries to the corresponding author, Howard White, [email protected]. 3ie receives funding for the working paper series from 3ie’s donors, which include UK aid, the Bill & Melinda Gates Foundation and the William and Flora Hewlett Foundation. A complete listing of 3ie’s donors is on the 3ie website

Restoration of peatlands and greenhouse gas balances

In this chapter the impact of peatland restoration on greenhouse gas fluxes is discussed based on a literature review. Casestudies are presented covering different peatland types, different regions and different starting conditions

The effect of row spacing on the harvestable yield and dry matter production of Russian wild ryegrass

Non-Peer Reviewe

Weathering the storm: developments in the acoustic sensing of wind and rain

An Acoustic Rain Gauge (ARG) analyses the underwater sound levels across a wide frequency range, classifies the observed spectrum according to likely source and then determines the local wind speed or rain rate as appropriate. Thispaper covers a trial on the Scotian Shelf off Canada, comparing the geophysical information derived from the acoustic signals with those obtained from other sources

Old high-redshift galaxies and primordial density fluctuation spectra

We have discovered a population of extremely red galaxies at $z\simeq 1.5$ which have apparent stellar ages of \gs 3 Gyr, based on detailed spectroscopy in the rest-frame ultraviolet. In order for galaxies to have existed at the high collapse redshifts indicated by these ages, there must be a minimum level of power in the density fluctuation spectrum on galaxy scales. This paper compares the required power with that inferred from other high-redshift populations. If the collapse redshifts for the old red galaxies are in the range $z_c\simeq 6$ -- 8, there is general agreement between the various tracers on the required inhomogeneity on 1-Mpc scales. This level of small-scale power requires the Lyman-limit galaxies to be approximately $\nu\simeq 3.0$ fluctuations, implying a very large bias parameter $b\simeq 6$. The high collapse redshifts of the red galaxies as deduced from gravitational collapse provides independent support for the ages estimated from their stellar populations. Such early-forming galaxies are rare, and their contribution to the cosmological stellar density is consistent with an extrapolation to higher redshifts of the star-formation rate measured at $z<5$; there is no evidence for a general era of spheroid formation at extreme redshifts.Comment: 9 Pages MNRAS in press. Uses MNRAS Plain TeX macro

Using logic models in research and evaluation of Health EDRM interventions

This chapter outlines how logic models can be used to conceptualize how interventions are intended to work, and their relationship with the broader context in which they take place – focusing on Health EDRM settings. Logic models are tools used to outline assumptions about the chains of processes, activities or events expected to occur during the implementation of an intervention, and the way in which these lead to changes in outcomes. They provide an initial set of assumptions about how different components of an intervention are expected to change outcomes, and can be used to develop further sub-research questions to investigate the validity of these assumptions. Logic models can also be used to communicate findings from research and evaluation activities, and can serve as useful tools in planning an intervention, including for the identification of relevant outcomes and monitoring of its delivery. However, this chapter will focus primarily on the use of logic models for research and evaluation purposes