Peru’s Experience in Sovereign Debt Management and Litigation: Some Lessons for the Legal Approach to Sovereign Indebtedness

The paper sheds light upon a specific issue: carbon leakage. Leakage can be understood as an unanticipated net carbon loss or gain, attributable to a climate policy, or reduction activities. Benign leakage effects are harmless. Unsettling are the ones that pose a threat to project’s environmental integrity. The Clean Development Mechanism (CDM) is no exception to such risk. In order to investigate leakage and the corresponding leakage calculation methods addressed in the CDM projects, a qualitative content analysis is conducted on 203 methodologies. Methodology documents serve as ideal textual data for examining CDM related leakage because the development of any new project must be based on methodologies. In relation to the research question, the content analysis synthesizes 11 types of leakage sources. Excluding the case where no leakage is considered, 10 type of leakage sources are then broadly classified as Activity Shift, Market Effects and Life Cycle Leakage. Their corresponding leakage calculation methods are described and reviewed in terms of their geographic reach, and leakage characteristics. A percentage pattern is presented in relation to each sector. The findings are that the vast majority of the CDM leakage calculation methods address primary leakage specific to each individual project at a localized scale, among which, methods addressing Life Cycle Leakage are in the predominant majority. Market Effects as secondary sources are acknowledged as a potential threat to the overall benefit, but the CDM methodologies offer no quantitative method

On the signature of z∼0.6z\sim 0.6 superclusters and voids in the Integrated Sachs-Wolfe effect

Through a large ensemble of Gaussian realisations and a suite of large-volume N-body simulations, we show that in a standard LCDM scenario, supervoids and superclusters in the redshift range $z\in[0.4,0.7]$ should leave a {\em small} signature on the ISW effect of the order $\sim 2 \mu$K. We perform aperture photometry on WMAP data, centred on such superstructures identified from SDSS LRGs, and find amplitudes at the level of 8 -- 11$\mu$K -- thus confirming the earlier work of Granett et al 2008. If we focus on apertures of the size \sim3.6\degr, then our realisations indicate that LCDM is discrepant at the level of $\sim4 \sigma$. If we combine all aperture scales considered, ranging from 1\degr--20\degr, then the discrepancy becomes $\sim2\sigma$, and it further lowers to $\sim 0.6 \sigma$ if only 30 superstructures are considered in the analysis (being compatible with no ISW signatures at $1.3\sigma$ in this case). Full-sky ISW maps generated from our N-body simulations show that this discrepancy cannot be alleviated by appealing to Rees-Sciama mechanisms, since their impact on the scales probed by our filters is negligible. We perform a series of tests on the WMAP data for systematics. We check for foreground contaminants and show that the signal does not display the correct dependence on the aperture size expected for a residual foreground tracing the density field. The signal also proves robust against rotation tests of the CMB maps, and seems to be spatially associated to the angular positions of the supervoids and superclusters. We explore whether the signal can be explained by the presence of primordial non-Gaussianities of the local type. We show that for models with \FNL=\pm100, whilst there is a change in the pattern of temperature anisotropies, all amplitude shifts are well below $<1\mu$K.Comment: 14 pages, 9 figures, matches accepted version in MNRA

The clustering of merging star-forming haloes: dust emission as high frequency arcminute CMB foreground

Future observations of CMB anisotropies will be able to probe high multipole regions of the angular power spectrum, corresponding to a resolution of a few arcminutes. Dust emission from merging haloes is one of the foregrounds that will affect such very small scales. We estimate the contribution to CMB angular fluctuations from objects that are bright in the sub-millimeter band due to intense star formation bursts following merging episodes. We base our approach on the Lacey-Cole merger model and on the Kennicutt relation which connects the star formation rate in galaxies with their infrared luminosity. We set the free parameters of the model in order to not exceed the SCUBA source counts, the Madau plot of star formation rate in the universe and COBE/FIRAS data on the intensity of the sub-millimeter cosmic background radiation. We show that the angular power spectrum arising from the distribution of such star-forming haloes will be one of the most significant foregrounds in the high frequency channels of future CMB experiments, such as PLANCK, ACT and SPT. The correlation term, due to the clustering of multiple haloes at redshift z~2-6, is dominant in the broad range of angular scales 200<l<3000. Poisson fluctuations due to bright sub-millimeter sources are more important at higher l, but since they are generated from the bright sources, such contribution could be strongly reduced if bright sources are excised from the sky maps. The contribution of the correlation term to the angular power spectrum depends strongly on the redshift evolution of the escape fraction of UV photons and the resulting temperature of the dust. The measurement of this signal will therefore give important information about galaxies in the early stage of their evolution.Comment: 18 pages, 16 figures. Accepted by Astronomy & Astrophysic

Implementation of a Fourier Matched Filter in CMB Analyses. Application to ISW Studies

Aims: Implement a matched filter (MF) cross-correlation algorithm in multipole space and compare it to the standard Angular Cross Power Spectrum (ACPS) method. Apply both methods on a Integrated Sachs Wolfe (ISW) - Large Scale Structure (LSS) cross correlation scenario and study how sky masks influence the multipole range where signal arises and its comparison to theoretical predictions. Methods: The MF requires the inversion of a multipole covariance matrix that if $f_{sky} \lt 1$ is generally non-diagonal and singular. We use a SVD approach that focuses on those modes carrying most of the information. We compare the MF to the ACPS in ISW-LSS Monte Carlo simulations, paying attention on the effect that a limited sky coverage has on the cross-correlation results. Results: Within the linear data model for which the MF is defined, the MF performs comparatively better than the ACPS for smaller values of $f_{sky}$ and scale dependent (non-Poissonian) noise fields. In the context of ISW studies both methods are comparable, although the MF performs slightly more sensitively under more restrictive masks. A preliminary study predicts that most of the ISW--LSS cross correlation S/N ratio should be found in the very large scales (50% of the S/N at $l\lt 10$, 90% at $l\lt 40-50$), and this is confirmed by Monte Carlo simulations. The statistical significance of our cross-correlation statistics reaches its maximum when considering $l\in [2,l_{max}]$, with $l_{max} \in[5,40]$ for all values of $f_{sky}$ observed, despite of the smoothing and power aliasing that aggressive masks introduce in Fourier space. This $l$-confinement of the ISW-LSS cross correlation should enable a safe distinction from other secondary effects arising at smaller angular scales.Comment: 9 pages, 5 figures, submitted to A&

On the Presence of Thermal SZ Induced Signal in the First Year WMAP Temperature Maps

Using available optical and X-ray catalogues of clusters and superclusters of galaxies, we build templates of tSZ emission as they should be detected by the WMAP experiment. We compute the cross-correlation of our templates with WMAP temperature maps, and interpret our results separately for clusters and for superclusters of galaxies. For clusters of galaxies, we claim 2-5 $\sigma$ detections in our templates built from BCS Ebeling et al. (1998), NORAS (Boehringer et al. 2000) and de Grandi et al. (1999) catalogues. In these templates, the typical cluster temperature decrements in WMAP maps are around 15-35 $\mu$K in the RJ range (no beam deconvolution applied). Several tests probing the possible influence of foregrounds in our analyses demonstrate that our results are robust against galactic contamination. On supercluster scales, we detect a diffuse component in the V & W WMAP bands which cannot be generated by superclusters in our catalogues (Einasto et al. 1994, 1997), and which is not present in the clean map of Tegmark, de Oliveira-Costa & Hamilton (2003). Using this clean map, our analyses yield, for Einasto's supercluster catalogues, the following upper limit for the comptonization parameter associated to supercluster scales: y_{SC} < 2.18 \time s 10^{-8} at the 95% confidence limit.Comment: MNRAS accepted. New section and minor changes include

Determining cosmic microwave background structure from its peak distribution

We present a new method for time-efficient and accurate extraction of the power spectrum from future cosmic microwave background (CMB) maps based on properties of peaks and troughs of the Gaussian CMB sky. We construct a statistic describing their angular clustering - analogously to galaxies, the 2-point angular correlation function, $\xi_\nu(\theta)$. We show that for increasing peak threshold, $\nu$, the $\xi_\nu(\theta)$ is strongly amplified and becomes measurable for $\nu\geq$1 on angular scales $\leq 10^\circ$. Its amplitude at every scale depends uniquely on the CMB temperature correlation function, $C(\theta)$, and thus the measured $\xi_\nu$ can be uniquely inverted to obtain $C(\theta)$ and its Legendre transform, the power spectrum of the CMB field. Because in this method the CMB power spectrum is deduced from high peaks/troughs of the CMB field, the procedure takes only $[f(\nu)]^2N^2$ operations where $f(\nu)$ is the fraction of pixels with $|\delta T|\geq\nu$ standard deviations in the map of $N$ pixels and is e.g. 0.045 and 0.01 for $\nu$=2 and 2.5 respectively. We develop theoretical formalism for the method and show with detailed simulations, using MAP mission parameters, that this method allows to determine very accurately the CMB power spectrum from the upcoming CMB maps in only $\sim(10^{-4}-10^{-3})\times N^2$ operations.Comment: To be published in Ap.J. Letters. Minor changes to match the journal versio