Testing the Hubble Law with the IRAS 1.2 Jy Redshift Survey

We test and reject the claim of Segal et al. (1993) that the correlation of redshifts and flux densities in a complete sample of IRAS galaxies favors a quadratic redshift-distance relation over the linear Hubble law. This is done, in effect, by treating the entire galaxy luminosity function as derived from the 60 micron 1.2 Jy IRAS redshift survey of Fisher et al. (1995) as a distance indicator; equivalently, we compare the flux density distribution of galaxies as a function of redshift with predictions under different redshift-distance cosmologies, under the assumption of a universal luminosity function. This method does not assume a uniform distribution of galaxies in space. We find that this test has rather weak discriminatory power, as argued by Petrosian (1993), and the differences between models are not as stark as one might expect a priori. Even so, we find that the Hubble law is indeed more strongly supported by the analysis than is the quadratic redshift-distance relation. We identify a bias in the the Segal et al. determination of the luminosity function, which could lead one to mistakenly favor the quadratic redshift-distance law. We also present several complementary analyses of the density field of the sample; the galaxy density field is found to be close to homogeneous on large scales if the Hubble law is assumed, while this is not the case with the quadratic redshift-distance relation.Comment: 27 pages Latex (w/figures), ApJ, in press. Uses AAS macros, postscript also available at http://www.astro.princeton.edu/~library/preprints/pop682.ps.g

Adsorption and diffusion of selenite on Boda Claystone Formation

This study provides adsorption and diffusion data of selenite on Boda Claystone Formation (BCF) which is a potential host rock of a deep geological disposal of high-level radioactive waste. The experiments were performed on two diverse core samples: one albitic claystone sample characteristic for the entire BCF and one pyrite containing sample sparsely occurring in BCF. The experiments were carried out under atmospheric conditions. Batch experiments were carried out to study the kinetics of adsorption at a high initial concentration (1.2 × 10−3 M), the adsorption isotherms and reversibility were investigated in the 10−10–10−3 M concentration range. Adsorption onto petrographic thin sections was done to study the elemental distribution on the microscale and the oxidation state of selenium. The maximum of the distribution coefficient was found as Kd ≈ 200 L/kg and a decrease was experienced around 10−6–10−7 M equilibrium concentration, which showed similarities to other argillaceous rocks. Isotopic exchange experiments revealed reversibility of selenite adsorption. Diffusion was studied with through-diffusion and in-diffusion experiments. Using X-ray fluorescence, despite a low initial concentration of 2.3 × 10−5 M in the in-diffusion experiment, a meaningful diffusion profile of selenium could be obtained, from which the selenite apparent diffusion coefficient Dappselenite = (1.5–4.3) × 10−14 m2/s and the selenite rock capacity factor αselenite = 1.4–2.2 were determined. As selenium species are redox sensitive the oxidation state of adsorbed species was studied with X-ray absorption near edge structure spectroscopy on Se–K edge. Adsorbed selenium remained in +IV oxidation state, however reduction was experienced on the pyritic sample

Surveying the Dynamic Radio Sky with the Long Wavelength Demonstrator Array

This paper presents a search for radio transients at a frequency of 73.8 MHz (4 m wavelength) using the all-sky imaging capabilities of the Long Wavelength Demonstrator Array (LWDA). The LWDA was a 16-dipole phased array telescope, located on the site of the Very Large Array in New Mexico. The field of view of the individual dipoles was essentially the entire sky, and the number of dipoles was sufficiently small that a simple software correlator could be used to make all-sky images. From 2006 October to 2007 February, we conducted an all-sky transient search program, acquiring a total of 106 hr of data; the time sampling varied, being 5 minutes at the start of the program and improving to 2 minutes by the end of the program. We were able to detect solar flares, and in a special-purpose mode, radio reflections from ionized meteor trails during the 2006 Leonid meteor shower. We detected no transients originating outside of the solar system above a flux density limit of 500 Jy, equivalent to a limit of no more than about 10^{-2} events/yr/deg^2, having a pulse energy density >~ 1.5 x 10^{-20} J/m^2/Hz at 73.8 MHz for pulse widths of about 300 s. This event rate is comparable to that determined from previous all-sky transient searches, but at a lower frequency than most previous all-sky searches. We believe that the LWDA illustrates how an all-sky imaging mode could be a useful operational model for low-frequency instruments such as the Low Frequency Array, the Long Wavelength Array station, the low-frequency component of the Square Kilometre Array, and potentially the Lunar Radio Array.Comment: 20 pages; accepted for publication in A

The Dynamical Status of the Cluster of Galaxies 1E0657-56

We present the results of a new spectroscopic and photometric survey of the hot X-ray cluster 1E0657-56, at z=0.296. We determine the presence of a low velocity dispersion subcluster, which is offset from the main cluster position by 0.7 Mpc and about 600 km/s. We determine the virial masses and total luminosities of the cluster and its subcluster, and solve for the two-body dynamical model. With additional constraints from the results of the analysis of the cluster X-ray emission by Markevitch et al. (2001), we find that the subcluster passed through the cluster centre about 0.15 Gyr ago. Taken at face value the mass of the subcluster is typical of a loose group. It is however difficult to establish the pre-merger mass of the colliding system. We provide tentative evidence that the subcluster is in fact the remnant core of a moderately massive cluster, stripped by the collision with 1E0657-56. The main cluster dynamics does not seem to have suffered from this collision. On the contrary, the cluster X-ray properties seem to have been significantly affected. We also discuss the effect of the subcluster collision in relation to starburst events and the cluster radio halo.Comment: Accepted for publication on A&

An XMM-Newton observation of the galaxy group MKW 4

We present an X-ray study of the galaxy group or poor cluster MKW 4. Working with XMM data we examine the distribution and properties of the hot gas which makes up the group halo. The inner halo shows some signs of structure, with circular or elliptical beta models providing a poor fit to the surface brightness profile. This may be evidence of large scale motion in the inner halo, but we do not find evidence of sharp fronts or edges in the emission. The temperature of the halo declines in the core, with deprojected spectral fits showing a central temperature of ~1.3 keV compared to ~3 keV at 100 kpc. In the central ~30 kpc of the group multi-temperature spectral models are required to fit the data, but they indicate a lack of gas at low temperatures. Steady state cooling flow models provide poor fits to the inner regions of the group and the estimated cooling time of the gas is long except within the central dominant galaxy, NGC 4073. Abundance profiles show a sharp increase in the core of the group, with mean abundance rising by a factor of two in the centre of NGC 4073. Fitting individual elements shows the same trend, with high values of Fe, Si and S in the core. We estimate that ~50% of the Fe in the central 40 kpc was injected by SNIa, in agreement with previous ASCA studies. Using our best fitting surface brightness and temperature models, we calculate the mass, gas fraction, entropy and mass-to-light ratio of the group. At 100 kpc (~0.1 virial radii) the total mass and gas entropy of the system (~2x10^13 Msol and ~300 keV cm^2) are quite comparable to those of other systems of similar temperature, but the gas fraction is rather low (~1%). We conclude that MKW 4 is a fairly relaxed group, which has developed a strong central temperature gradient but not a large-scale cooling flow.Comment: 17 pages, 9 postscript figures, accepted for publication in MNRA

The VIRMOS deep imaging survey II: CFH12K BVRI optical data for the 0226-04 deep field

(abridged) In this paper we describe in detail the reduction, preparation and reliability of the photometric catalogues which comprise the 1.2 deg^2 CFH12K-VIRMOS deep field. The survey reaches a limiting magnitude of BAB~26.5, VAB~26.2, RAB~25.9 IAB~25.0 and contains 90,729 extended sources in the magnitude range 18.0<IAB<24.0. We demonstrate our catalogues are free from systematic biases and are complete and reliable down these limits. We estimate that the upper limit on bin-to-bin systematic photometric errors for the I- limited sample is ~10% in this magnitude range. We estimate that 68% of the catalogues sources have absolute per co-ordinate astrometric uncertainties less than ~0.38" and ~0.32" (alpha,delta). Our internal (filter-to-filter) per co-ordinate astrometric uncertainties are 0.08" and 0.08" (alpha,delta). We quantify the completeness of our survey in the joint space defined by object total magnitude and peak surface brightness. Finally, we present numerous comparisons between our catalogues and published literature data: galaxy and star counts, galaxy and stellar colours, and the clustering of both point-like and extended populations. In all cases our measurements are in excellent agreement with literature data to IAB<24.0. This combination of depth and areal coverage makes this multi-colour catalogue a solid foundation to select galaxies for follow-up spectroscopy with VIMOS on the ESO-VLT and a unique database to study the formation and evolution of the faint galaxy population to z~1 and beyond.Comment: 18 pages, 23 figures, accepted for publication in A&

Das Basler Interview für Psychosen (BIP): Struktur, Reliabilität und Validität

Hintergrund: Obwohl in den letzten Jahren zahlreiche Instrumente entwickelt worden sind, um Psychoserisikopersonen und Psychoseersterkrankte zu identifizieren, gab es bisher keine geeigneten Instrumente, um solche Personen ausführlicher über ihren Krankheitsverlauf sowie die Risikofaktoren und frühen Indikatoren der Erkrankung zu befragen. Wir haben deshalb das Basler Interview für Psychosen (BIP) entwickelt. Ziel der vorliegenden Arbeit ist es, die Entwicklung und den Aufbau des BIP zu beschreiben sowie über seine psychometrischen Eigenschaften zu berichten. Methoden: Das BIP ist ein halbstrukturiertes klinisches Anamneseinterview, das im Rahmen des Basler Projekts zur Früherkennung von Psychosen (FePsy) auf der Basis der wichtigsten in der Literatur beschriebenen Risikofaktoren und Indikatoren für Psychosen und unter Berücksichtigung schon existierender Fragebögen entwickelt wurde. Es gliedert sich in sechs Bereiche: 1. Soziale und körperliche Entwicklung/Familie, 2. Anzeichen und Symptome, 3. Vulnerabilität, 4. Hilfesucheverhalten, 5. Krankheitseinsicht, 6. Interviewereinschätzung. Um die Interrater-Reliabilität der Items der Abschnitte 2 und 3 zu bestimmen, wurden 20 Patienten von insgesamt 8 unterschiedlichen Ratern beurteilt. Die faktorielle Struktur des Abschnitts 2.3 „Prodromi und Symptome“ wurde in einer Stichprobe von 120 Psychoserisikopersonen und 77 Erstpsychosepatienten untersucht. Auf der Basis der gefundenen Faktorstruktur wurden neue Skalen gebildet und auf ihre Reliabilität und Validität untersucht. Ergebnisse: Von 153 untersuchten Items der Abschnitte 2 und 3 wurden 150 (98 %) mit ausreichend hoher Übereinstimmung (Interrater-Reliabilität > 0,4) eingeschätzt. Die Items des Abschnitts 2.3 „Prodromi und Symptome“ konnten zu 5 Subskalen gruppiert werden. Die Subskalen wiesen überwiegend gute bis sehr gute interne Konsistenzen, Homogenitäten und diskriminante und konvergente Validitäten auf. Für die Subskalen „Positive psychotische Symptome“ und „Störungen des Denkens“ sowie den Gesamtscore konnte zudem eine prädiktive Validität nachgewiesen werden. Diskussion: Mit dem BIP haben wir erstmals ein halbstrukturiertes klinisches Anamneseinterview konstruiert und validiert, das geeignet ist, Psychoserisikopatienten und Psychoseersterkrankte detailliert über Psychoserisikofaktoren und -indikatoren sowie den psychopathologischen Verlauf seit der Kindheit zu befragen. Wir konnten zeigen, dass das BIP hervorragende psychometrische Eigenschaften aufweist. BACKGROUND: Although several instruments have been developed to identify patients with an at-risk mental state (ARMS) for psychosis and first episode of psychosis (FEP), up to now there were no instruments for a detailed assessment of risk factors and indicators of emerging psychosis and the temporal development of psychiatric symptoms over the whole life span in these patients. We therefore developed the Basle Interview for Psychosis (BIP). The aim of this study is to describe the development of the BIP and to report about its psychometric properties. METHODS: The BIP is a comprehensive semi-structured interview that was developed for the Basel early detection of psychoses (FePsy) study. Its items were derived from the most important risk factors and indicators of psychosis described in the literature and from several existing instruments. It contains the following six sections: 1) social and physical development and family, 2) signs and symptoms, 3) vulnerability, 4) help-seeking behavior, 5) illness insight, 6) evaluation of the interview. To estimate the inter-rater reliabilities of the items of sections 2 and 3, 20 interviews were conducted and rated by 8 well-trained raters. The factorial structure of the BIP section "signs and symptoms" was explored in a sample of 120 ARMS and 77 FEP patients. On the basis of the discovered factorial structure, we created new subscales and assessed their reliabilities and validities. RESULTS: Of the 153 studied items of sections 2 and 3, 150 (98 %) were rated with sufficiently high agreement (inter-rater reliability &gt; 0.4). The items of section "signs and symptoms" could be grouped into 5 subscales with predominantly good to very good internal consistencies, homogeneities, and discriminant and convergent validities. Predictive validities could be demonstrated for the subscales "Positive Psychotic Symptoms", "Disturbance of Thinking" and the total score. DISCUSSION: The BIP is the first interview for comprehensively assessing risk factors and indicators of emerging psychosis and the temporal development of psychiatric symptoms over the whole life span, which has been validated in ARMS and FEP patients. We could show that the BIP has excellent psychometric properties

Multimorbidity in bipolar disorder and under-treatment of cardiovascular disease: a cross sectional study

Background: Individuals with serious mental disorders experience poor physical health, especially increased rates of cardiometabolic morbidity and premature morbidity. Recent evidence suggests that individuals with schizophrenia have numerous comorbid physical conditions which may be under-recorded and under-treated but to date very few studies have explored this issue for bipolar disorder. Methods:We conducted a cross-sectional analysis of a dataset of 1,751,841 registered patients within 314 primary-care practices in Scotland, U.K. Bipolar disorder was identified using Read Codes recorded within electronic medical records. Data on 32 common chronic physical conditions were also assessed. Potential prescribing inequalities were evaluated by analyzing prescribing data for coronary heart disease (CHD) and hypertension. Results: Compared to controls, individuals with bipolar disorder were significantly less likely to have no recorded physical conditions (OR 0.59, 95% CI 0.54-0.63) and significantly more likely to have one physical condition (OR 1.27, 95% CI 1.16-1.39), two physical conditions (OR 1.45, 95% CI 1.30-1.62) and three or more physical conditions (OR 1.44, 95% CI 1.30-1.64). People with bipolar disorder also had higher rates of thyroid disorders, chronic kidney disease, chronic pain, chronic obstructive airways disease and diabetes but, surprisingly, lower recorded rates of hypertension and atrial fibrillation. People with bipolar disorder and comorbid CHD or hypertension were significantly more likely to be prescribed no antihypertensive or cholesterol-lowering medications compared to controls, and bipolar individuals with CHD or hypertension were significantly less likely to be on 2 or more antihypertensive agents. Conclusions: Individuals with bipolar disorder are similar to individuals with schizophrenia in having a wide range of comorbid and multiple physical health conditions. They are also less likely than controls to have a primary-care record of cardiovascular conditions such as hypertension and atrial fibrillation. Those with a recorded diagnosis of CHD or hypertension were less likely to be treated with cardiovascular medications and were treated less intensively. This study highlights the high physical healthcare needs of people with bipolar disorder, and provides evidence for a systematic under-recognition and under-treatment of cardiovascular disease in this group

SPT-CL J0546-5345: A Massive z > 1 Galaxy Cluster Selected Via the Sunyaev-Zel'dovich Effect with the South Pole Telescope

We report the spectroscopic confirmation of SPT-CL J0546-5345 at = 1.067. To date this is the most distant cluster to be spectroscopically confirmed from the 2008 South Pole Telescope (SPT) catalog, and indeed the first z > 1 cluster discovered by the Sunyaev-Zel'dovich Effect (SZE). We identify 21 secure spectroscopic members within 0.9 Mpc of the SPT cluster position, 18 of which are quiescent, early-type galaxies. From these quiescent galaxies we obtain a velocity dispersion of 1179^{+232}_{-167} km/s, ranking SPT-CL J0546-5345 as the most dynamically massive cluster yet discovered at z > 1. Assuming that SPT-CL J0546-5345 is virialized, this implies a dynamical mass of M_200 = 1.0^{+0.6}_{-0.4} x 10^{15} Msun, in agreement with the X-ray and SZE mass measurements. Combining masses from several independent measures leads to a best-estimate mass of M_200 = (7.95 +/- 0.92) x 10^{14} Msun. The spectroscopic confirmation of SPT-CL J0546-5345, discovered in the wide-angle, mass-selected SPT cluster survey, marks the onset of the high redshift SZE-selected galaxy cluster era.Comment: ApJ, in pres