Interchanging Interactive 3-d Graphics for Astronomy

We demonstrate how interactive, three-dimensional (3-d) scientific visualizations can be efficiently interchanged between a variety of mediums. Through the use of an appropriate interchange format, and a unified interaction interface, we minimize the effort to produce visualizations appropriate for undertaking knowledge discovery at the astronomer's desktop, as part of conference presentations, in digital publications or as Web content. We use examples from cosmological visualization to address some of the issues of interchange, and to describe our approach to adapting S2PLOT desktop visualizations to the Web. Supporting demonstrations are available at http://astronomy.swin.edu.au/s2plot/interchange/Comment: 10 pages, 7 figures, submitted to Publications of the Astronomical Society of Australia. v2. Revised title, revised figure 1, fixed typos, minor additions to future work sectio

WHAM Observations of H-alpha from High-Velocity Clouds: Are They Galactic or Extragalactic?

It has been suggested that high velocity clouds may be distributed throughout the Local Group and are therefore not in general associated with the Milky Way galaxy. With the aim of testing this hypothesis, we have made observations in the H-alpha line of high velocity clouds selected as the most likely candidates for being at larger than average distances. We have found H-alpha emission from 4 out of 5 of the observed clouds, suggesting that the clouds under study are being illuminated by a Lyman continuum flux greater than that of the metagalactic ionizing radiation. Therefore, it appears likely that these clouds are in the Galactic halo and not distributed throughout the Local Group.Comment: 12 pages, 5 eps figures, accepted for publication in ApJ Letter

Perspectives On The Sources And Eventual Outcome Of The 2008 Economic And Financial Crisis: A Panel Discussion

In October 2008 the Southern Utah University School of Business held a panel discussion on the current economic crisis. This discussion was part of the School’s Business Convocation series and was open to the public. The panel was designed with two components in mind. First, a pair of academics with expertise in financial institutions and business cycles offered historical and theoretical perspectives on the crisis. Second, a pair of professionals – a local banking official and a fund manager – offered perspectives on the current financial situation and practical experience based on the policy responses to past crises. As moderator, Joe Baker asked each panelist to make a short presentation on a question of general interest that was related to their area of expertise; this was followed by an open question and answer session. The participating panelists and opening questions follow. 1. Stephen Evans, Professor of Finance: Dr. Evans teaches courses on financial institutions and was asked to provide background of how the crisis occurred and what the proposed government bailout plan is expected to accomplish. 2. David Tufte, Associate Professor of Economics: Dr. Tufte is a macroeconomist and was asked to discuss the macroeconomic implications of the crisis in such areas as inflation, interest rates, economic growth and unemployment. 3. Mr. Robb Kerry, Chief Credit Officer of ADB Bank: Mr. Kerry has an extensive background in banking as a bank regulator and banker. Mr. Kerry was asked to discuss the implications of the crisis on banking credit and lending. Mr. Steve Harrop, Finance Professional in Residence: Mr. Harrop was a mutual fund manager for several decades before joining the School of Business faculty where he teaches investments and manages (pro bono) an investment fund. Mr. Harrop will discuss the implications of the crisis on the stock and bond markets

Galactic contamination in the QMAP experiment

We quantify the level of foreground contamination in the QMAP Cosmic Microwave Background (CMB) data with two objectives: (a) measuring the level to which the QMAP power spectrum measurements need to be corrected for foregrounds and (b) using this data set to further refine current foreground models. We cross-correlate the QMAP data with a variety of foreground templates. The 30 GHz Ka-band data is found to be significantly correlated with the Haslam 408 MHz and Reich and Reich 1420 MHz synchrotron maps, but not with the Diffuse Infrared Background Experiment (DIRBE) 240, 140 and 100 micron maps or the Wisconsin H-Alpha Mapper (WHAM) survey. The 40 GHz Q-band has no significant template correlations. We discuss the constraints that this places on synchrotron, free-free and dust emission. We also reanalyze the foreground-cleaned Ka-band data and find that the two band power measurements are lowered by 2.3% and 1.3%, respectively.Comment: 4 ApJL pages, including 4 figs. Color figures and data at http://www.hep.upenn.edu/~angelica/foreground.html#qmap or from [email protected]

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 WHAM H-alpha 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 ft telescope by Finkbeiner et al. failed to find the corresponding 8 sigma 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 micron only on large angular scales. In support of this grain segregation model, we find the best spinning dust template to involve higher frequency maps in the range 12-60 micron, where emission from transiently heated small grains is important. Upcoming CMB experiments such as ground-based interferometers, MAP and Planck LFI with high resolution at low frequencies should allow a definitive test of this model.Comment: Minor revisions to match accepted ApJ version. 6 pages, 4 figs. Color figures and more foreground information at http://www.hep.upenn.edu/~angelica/foreground.html#spin or from [email protected]

Westerbork HI observations of high-velocity clouds near M31 and M33

We have undertaken high-resolution follow-up of a sample of high velocity HI clouds apparently associated with M31. Our sample was chosen from the population of high-velocity clouds (HVCs) detected out to 50 kpc projected radius of the Andromeda Galaxy by Thilker et al. (2004) with the Green Bank Telescope. Nine pointings were observed with the Westerbork Synthesis Radio Telescope to determine the physical parameters of these objects and to find clues to their origin. One additional pointing was directed at a similar object near M33. At 2' resolution we detect 16 individual HVCs around M31 and 1 HVC near M33 with typical HI masses of a few times 10^5 solar masses and sizes of the order of 1 kpc. Estimates of the dynamical and virial masses of some of the HVCs indicate that they are likely gravitationally dominated by additional mass components such as dark matter or ionised gas. Twelve of the clouds are concentrated in an area of only 1 by 1 degree at a projected separation of less than 15 kpc from the disk of M31. This HVC complex has a rather complicated morphological and kinematical structure and partly overlaps with the giant stellar stream of M31, suggesting a tidal origin. Another detected feature is in close proximity, in both position and velocity, with NGC 205, perhaps also indicative of tidal processes. Other HVCs in our survey are isolated and might represent primordial, dark-matter dominated clouds.Comment: 18 pages, 16 figures, accepted for publication in Astronomy & Astrophysic

The extragalactic background and its fluctuations in the far-infrared wavelengths

A Cosmic Far-InfraRed Background (CFIRB) has long been predicted that would traces the intial phases of galaxy formation. It has been first detected by Puget et al.(1996) using COBE data and has been later confirmed by several recent studies (Fixsen et al. 1998, Hauser et al. 1998, Lagache et al. 1999). We will present a new determination of the CFIRB that uses for the first time, in addition to COBE data, two independent gas tracers: the HI survey of Leiden/Dwingeloo (hartmann, 1998) and the WHAM H$_{\alpha}$ survey (Reynolds et al 1998). We will see that the CFIRB above 100 micron is now very well constrained. The next step is to see if we can detect its fluctuations. To search for the CFIRB fluctuations, we have used the FIRBACK observations. FIRBACK is a deep cosmological survey conducted at 170 micron with ISOPHOT (Dole et al., 2000). We show that the emission of unresolved extra-galactic sources clearly dominates, at arcminute scales, the background fluctuations in the lowest galactic emission regions. This is the first detection of the CFIRB fluctuations.Comment: To appear in "ISO Surveys of a Dusty Universe", Workshop at Ringberg Castle, November 8 - 12, 199

Minard revisited: exploring augmented reality in information design

This study intends to test and confirm the interest and viability of incorporating augmented reality (AR) technologies in cultural mediation driven by information design, focusing on narrative representation. It is specifically intended to explore semantic relations between reality and virtuality in augmented narratives, ie. expanded narratives through the multimodality enhanced by the use of interactive processes based in augmented reality systems. Departing from Charles Minard’s Figurative Map (1869), three experiments were conducted, in order to reinterpret the program embodied in that artefact, testing several hypotheses in which, through augmented reality, the combination of different modes and media configures different semantic relations between real and virtual. The action-reflection approach undertaken with Figurative Map experiments enabled us to observe and openly systematize different augmented reality functions regarding the physical instance, which can potentially expand traditional forms of information design. Although they are not entirely extrapolatable, the proposal of virtual functions regarding reality were repurposed and adapted from the illustration field, specifically from the semantic relation between text and image. It is acknowledged that this is an open model to be reconsidered and reformulated through several action-reflection iterations and fostered through the narrative study.publishe

Measurement of a Magnetic Field in a Leading Arm High Velocity Cloud

Using a recent catalogue of extragalactic Faraday rotation derived from the NRAO VLA Sky Survey we have found an agreement between Faraday rotation structure and the HI emission structure of a High Velocity Cloud (HVC) associated with the Leading Arm of the Magellanic System. We suggest that this morphological agreement is indicative of Faraday rotation through the HVC. Under this assumption we have used 48 rotation measures through the HVC, together with estimates of the electron column density from H-\alpha\ measurements and QSO absorption lines to estimate a strength for the line-of-sight component of the coherent magnetic field in the HVC of > 6 {\rm \mu G}$. A coherent magnetic field of this strength is more than sufficient to dynamically stabilize the cloud against ram pressure stripping by the Milky Way halo and may also provide thermal insulation for the cold cloud. We estimate an upper limit to the ratio of random to coherent magnetic field of$B_{r}/B_{||} < 0.8$, which suggests that the random field does not dominate over the coherent field as it does in the Magellanic Clouds from which this HVC likely originates.Comment: 17 pages, 3 figure

Some considerations for the communication of results of air pollution health effects tracking

Communicating effectively and efficiently on air quality and its health impacts is an important but difficult and complex task. It requires careful consideration of the audience one wants to reach, the messages one is trying to present, the venue through which the message will be delivered. The audience, context, technique, and content factors may affect how well it is heard and how appropriately it is interpreted. In this short paper, I describe many of these concerns and provide some suggestions for how best to address them. However, since every audience differs in goals, characteristics, and nature, what is most important is implementing an effective communications program. This program should include frequent two-way communication, repeated and on-going evaluation of how well the audience understands the messages, and consideration of how to improve the delivery