Aled Jones

Cross-Correlation of Tenerife Data with Galactic Templates-Evidence for Spinning Dust?

The recent discovery of dust-correlated diffuse microwave emission has prompted two rival explanations: free-free emission and spinning dust grains. We present new detections of this component at 10 and 15 GHz by the switched-beam Tenerife experiment. The data show a turnover in the spectrum and thereby support the spinning dust hypothesis. We also present a significant detection of synchrotron radiation at 10 GHz, which is useful for normalizing foreground contamination of cosmic microwave background experiments at high galactic latitudes.

A NEW SPIN ON GALACTIC DUST

We present a new puzzle involving Galactic microwave emission and attempt to resolve it. On one hand, a cross-correlation analysis of the Wisconsin Hα Mapper map with the Tenerife 10 and 15 GHz maps shows that the well-known DIRBE correlated microwave emission cannot be dominated by free-free emission. On the other hand, recent high-resolution observations in the 8-10 GHz range with the Green Bank 140 foot telescope by Finkbeiner et al. failed to find the corresponding 8 σ signal that would be expected in the simplest spinning-dust models. So what physical mechanism is causing this ubiquitous dust-correlated emission? We argue for a model predicting that spinning dust is the culprit after all, but that the corresponding small grains are well correlated with the larger grains seen at 100 μm only on large angular scales. In support of this grain-segregation model, we find that the best spinning-dust template involves higher frequency maps in the range 12-60 μm, in which emission from transiently heated small grains is important. Upcoming cosmic microwave background experiments such as ground-based interferometers, the Microwave Anisotropy Probe, and the Planck low-frequency interferometer with high resolution at low frequencies should allow a definitive test of this model.

Wavelet analysis and the detection of non‐Gaussianity in the cosmic microwave background

We investigate the use of wavelet transforms in detecting and characterizing non-Gaussian structure in maps of the cosmic microwave background (CMB). We apply the method to simulated maps of the Kaiser–Stebbins effect resulting from cosmic strings, on to which Gaussian signals of varying amplitudes are superposed. We find that the method significantly outperforms standard techniques based on measuring the moments of the pixel temperature distribution. We also compare the results with those obtained using techniques based on Minkowski functionals, and we again find the wavelet method to be superior. In particular, using the wavelet technique, we find that it is possible to detect non-Gaussianity even in the presence of a superposed Gaussian signal with 3 times the rms amplitude of the original cosmic string map. We also find that the wavelet technique is useful in characterizing the angular scales at which the non-Gaussian signal occurs.

The effect of point sources on satellite observations of the cosmic microwave background

ABSTRACT We study the effect of extragalactic point sources on satellite observations of the cosmic mi-crowavebackground(CMB). In order to separate the contributionsdue to differentforegroundcomponents, a maximum-entropy method is applied to simulated observations by the PlanckSurveyor satellite. In addition to point sources, the simulations include emission from theCMB and the kinetic and thermal Sunyaev-Zel’dovich (SZ) effects from galaxy clusters, aswell as Galactic dust, free-free and synchrotron emission.We find that the main input com-ponents are faithfully recovered and, in particular, that the quality of the CMB reconstructionis only slightly reduced by the presence of point sources. In addition, we find that it is pos-sible to recover accurate point source catalogues at each of the Planck Surveyor observingfrequencies.Key words: methods: data analysis – techniques: image processing – cos mic microwavebackground. 1 INTRODUCTIONA new generation of cosmic microwave background (CMB) satel-lite missions are currently in the final stages of design. The NASAMAP satellite is expected to be launched by 2000, followed by theESA Planck Surveyor in 2007 (Bersanelli et al. 1996). Both mis-sions will provide detailed all-sky maps of the CMB anisotropies,leading to definitive measurements of the CMB power spectrum .This should allow tight constraints to be placed on fundamentalcosmological parameters and distinguish between competing the-ories of structure formation in the early Universe such as inflationand topological defects.The maps produced by these satellites will, however, containcontributions from various foreground components, most notablyGalactic dust, free-free and synchrotron emission as well as thekinetic and thermal SZ effects from galaxy clusters. In addition,significant contamination from extragalactic point source s is alsoexpected. It is therefore clear that in order to obtain maps of theCMB anisotropies alone, it is necessary to separate the emissiondue to these various components.In a previous paper, Hobson et al. (1998) (hereafter Paper I)use a non-linear maximum-entropy method (MEM) to separate theemission due to the different foreground components from simu-lated Planck Surveyor observations of a 10 ×10 deg

Bleomycin lung damage: the pathology and nature of the lesion.

The pathology of two cases of pulmonary damage due to bleomycin is described. The drug damages the alveolar walls. A sequence of pathological changes could be traced commencing with oedema, intra-alveolar fibrin and haemorrhage, followed by type II pneumocyte hyperplasia associated with bronchial epithelial squamous metaplasia. This led to intra-alveolar and alveolar wall collagen formation producing diffuse interstitial fibrosis with microcyst formation associated with cuboidalization of the epithelium. These changes are similar to those seen in experimental bleomycin damage in mice, where it has been shown that the changes are the result of vascular damage and type I pneumocyte necrosis. It is inferred that human diffuse alveolar damage develops in the same way.

APOCRINE CYSTADENOMA A REPORT OF TWO CASES OCCURRING ON THE PREPUCE

SUMMARY.— Two apocrine cystadenomas occurring on the prepuce are described. The relationship of this tumour to hidradenoma papilliferum in the female is discussed.

The Tenerife Cosmic Microwave Background Maps: Observations and First Analysis

The results of the Tenerife cosmic microwave background (CMB) experiments are presented. These observations cover 5000 and 6500 deg2 on the sky at 10 and 15 GHz, respectively, centered on decl. ~ +35°. The experiments are sensitive to multipoles l = 10-30 that correspond to the Sachs-Wolfe plateau of the CMB power spectra. The sensitivity values of the data are ~31 and ~12 μK at 10 and 15 GHz, respectively, in a beam-size region (5° × 5°). The data at 15 GHz show clear detection of structure at high Galactic latitude; the results at 10 GHz are compatible with these, but at lower significance. A likelihood analysis of the 10 and 15 GHz data at high Galactic latitude, assuming a flat CMB band power spectrum, gives a signal ΔTl = 30 μK (68% C.L.). Including the possible contaminating effect due to the diffuse Galactic component, the CMB signal is ΔTl = 30 μK. These values are stable against the Galactic cut chosen. Assuming a Harrison-Zeldovich spectrum for the primordial fluctuations, the above values imply an expected quadrupole Qrms-ps = 20 μK, which agrees with previous results from these experiments, and which are compatible with the COBE DMR data in the case of the standard inflationary cold dark matter models.

Primary tracheobronchial amyloidosis with tracheobronchopathia osteoplastica.

Abstract Primary tracheobronchial amyloidosis associated with extensive tracheobronchopathia osteoplastica, found at necropsy in a 76-year-old woman, is described.

Alveolar cell carcinoma occurring in idiopathic interstitial pulmonary fibrosis

Summary The clinical and pathological findings are presented in the case of a patient with idiopathic diffuse interstitial pulmonary fibrosis complicated by the development of a diffuse or pneumonic type of alveolar cell carcinoma with hilar gland metastases. The relationship between atypical epithelial hyperplasia and alveolar cell carcinoma is discussed. A brief summary of reports of malignant lung neoplasms in diffuse interstitial fibrosis is presented.

New Cosmological Structures on Medium Angular Scales Detected with the Tenerife Experiments

We present observations at 10 and 15 GHz taken with the Tenerife experiments in a band of the sky at declination +35°. These experiments are sensitive to multipoles in the range l = 10-30. The sensitivities per beam are 56 and 20 μK for the 10 and 15 GHz data, respectively. After subtraction of the prediction of known radio sources, the analysis of the data at 15 GHz at high Galactic latitude shows the presence of a signal with amplitude ΔTrms ~ 32 μK. In the case of a Harrison-Zeldovich spectrum for the primordial fluctuations, a likelihood analysis shows that this signal corresponds to a quadrupole amplitude Qrms-PS = 20.1+ 7.1−5.4 μK, in agreement with our previous results at declination +40° and with the results of the COBE DMR. There is clear evidence for the presence of individual features in the right ascension range 190°-250° with a peak-to-peak amplitude of ~110 μK. A preliminary comparison between our results and COBE DMR predictions for the Tenerife experiments clearly indicates the presence of individual features common to both. The constancy in amplitude over such a large range in frequency (10-90 GHz) is strongly indicative of an intrinsic cosmological origin for these structures.