Multi-Wavelength Observations of Short-Duration Gamma-Ray Bursts: Recent Results

The number of detections as well as significantly deep non-detections of optical/NIR afterglows of Type I (short-duration population) Gamma-Ray Bursts (GRBs) has become large enough that statistically meaningful samples can now be constructed. I present within some recent results on the luminosity distribution of Type I GRB afterglows in comparison to those of Type II GRBs (collapsar population), the issue of the existence of jet breaks in Type I GRB afterglows, and the discovery of dark Type I GRBs.Comment: 10 pages, 3 figures, based on an invited talk, to appear in the proceedings of the Gamma-Ray Burst Symposium 2012- IAA-CSIC - Marbella, editors: Castro-Tirado, A. J., Gorosabel, J. and Park, I. H; v2: accepted, slightly expanded, minor changes after referee repor

Digital Scholarship: Applying Digital Tools to Undergraduate Student Research Papers, A Proposal for a Freshman Seminar. Part I: Definition of Student Research Methodology

There are many digital tools that can be used for research and presentation in nearly every college discipline, including the social sciences and humanities. These tools hold the promise to radically change both the process and products of research. But in their application these tools have failed miserably to live up to their promise. This paper is based on the hypothesis that one reason these tools do reach their potential is that there is no systemic way to include them in research process, resulting in the tools being seen as ways to improve the final research product. This results in the tools becoming just an added on kludge, and leading researchers to the conclude that they are hard to use, full of bugs and other problems, and that they do not bring a lot of value to the research. This paper is an attempt to address this problem of including digital tools in a research process. It is part of a series of papers proposing a systematic methodology for including digital tools in a research process. This paper is the first, and outlines a methodology for the research process that allows the application of digital tools to a small area, undergraduate student research papers. It will outline a development process that will systematize the steps in the research process. These steps will then be used to classify the digital tools, and show how they can be applied to the research process. The final product of this paper will be a process methodology for creating student research papers to be used in a class to be run as a freshman seminar. The students will be taught this research methodology, and be led through the development of a research paper using the steps defined in this methodology. The steps in the process being enhanced using appropriate digital tools applicable to each step in the methodology. The ability of the students to do research using the research methodology and digital tools will be measured by the degree of success the students have in completing a humanities/social science research product as part of the class. The students will be followed in a longitudinal study by asking them to complete a short survey at the end of each year of their undergraduate education

Implementing a One Address CPU in Logisim

Most computer users have an incorrect, but useful, cognitive metaphor for computers in which the user says (or types or clicks) something and a mystical, almost intelligent or magical, behavior happens. It is not a stretch to describe computer users as believing computers follow the laws of magic, where some magic incantation is entered, and the computer responds with an expected, but magical, behavior. This magic computer does not actually exist. In reality computer are machines, and every action a computer performs reduces to a set of mechanical operations. In fact the first complete definition of a working computer was a mechanical machine designed by Charles Babbage in 1834, and would have run on steam power. Probably the biggest success of Computer Science (CS) in the 20th century was the development of abstractions that hide the mechanical nature of computers. The fact that average people use computers without ever considering that they are mechanistic is a triumph of CS designers. This purpose of this monograph is to break the abstract understanding of a computer, and to explain a computer’s behavior in completely in mechanistic terms. It will deal specifically with the Central Processing Unit (CPU) of the computer, as this is where the magic happens. All other parts of a computer can be seen as just providing information for the CPU to operate on. This monograph will deal with a specific type of CPU, a one-address CPU, and will explain this CPU using only standard gates, specifically AND, OR, NOT, NAND and XOR gates, and 4 basic Integrated Circuits (ICs), the Decoder, Multiplexer, Adder, and Flip Flop. All of these gates and components can be described as mechanical transformations of input data to output data, and the overall CPU can then be seen as a mechanical device.https://cupola.gettysburg.edu/oer/1002/thumbnail.jp

Visualizing Fantasy Fiction: Design of a Class in Digital Scholarship and Visualization, including Research, Organization and Digital Visualization, that Does Not Require Programming or IT support

This paper outlines a course to integrate digital visualizations into undergraduate research. These visualizations will include mapping and timelines of events, and the ability to hyperlink the events, characters, and story lines in a fantasy fiction story such as Lord of the Rings or A Game of Thrones. The digital scholarship will involve the methodology for collecting, organizing, and representing the data for the visualizations. The topic for the visualizations in this paper is fantasy fiction; however the methods to develop these visualizations will be applicable to many academic disciplines, including the humanities and social sciences. The paper outlines the justification for this class, the appropriate audience for this class, and the tools needed. Types of projects and homework assignments to implement the visualizations are suggested. It concludes with a syllabus outlining a typical schedule for this class

Programming Safety Tips: Why You Should Use Immutable Objects or How to create programs with bugs that can never be found or fixed.

Program safety deals with how to make programs as error free as possible. The hardest errors in a program for a programmer to find are often errors in using memory. There are two reasons for this. The first is that errors in accessing memory almost never show problems in the proximate area of the program where the error is made. The error has no apparent impact when it is made, but often causes catastrophic results to occur much later in the program, in areas of the program unrelated to memory error that caused it. The second reason memory errors are so difficult to find is that the working of memory is often poorly understood by most novice, and many professional, programmers. This makes it difficult for many programmers to even understand why an action causes the error. This article will show an example of a program error that can easily occur when memory access is poorly understood. This leads to program errors that are very easy to fix when they are found, but extremely difficult to find. The article will then explain how many memory errors can be easily avoided by following the very simple rule, “Make all object immutable unless there is a good reason to make them mutable”, and why immutable objects are an essential tool in good, safe programming practice

Airplanes in Horizontal Curvilinear Flight

War airplanes require not only high speed and the ability to climb rapidly, but also the ability to transverse sharp curves quickly. Here, an attempt is made to give a simple method of calculating horizontal curvilinear flight. A method for determining the area of the aileron and rubber surfaces are also indicated. The discussion given here applies primarily to single and two-seater airplanes, although it can be extended to larger airplanes

The Afterglows of Swift-era Gamma-ray Bursts. I. Comparing pre-Swift and Swift-era Long/Soft (Type II) GRB Optical Afterglows

We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to 2009 September, for a total of 76 GRBs, and present an additional three pre-Swift GRBs not included in an earlier sample. Furthermore, we publish 840 additional new photometry data points on a total of 42 GRB afterglows, including large data sets for GRBs 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A, and 080810. We analyzed the light curves of all GRBs in the sample and derived spectral energy distributions for the sample with the best data quality, allowing us to estimate the host-galaxy extinction. We transformed the afterglow light curves into an extinction-corrected z = 1 system and compared their luminosities with a sample of pre-Swift afterglows. The results of a former study, which showed that GRB afterglows clustered and exhibited a bimodal distribution in luminosity space, are weakened by the larger sample. We found that the luminosity distribution of the two afterglow samples (Swift-era and pre-Swift) is very similar, and that a subsample for which we were not able to estimate the extinction, which is fainter than the main sample, can be explained by assuming a moderate amount of line-of-sight host extinction. We derived bolometric isotropic energies for all GRBs in our sample, and found only a tentative correlation between the prompt energy release and the optical afterglow luminosity at 1 day after the GRB in the z = 1 system. A comparative study of the optical luminosities of GRB afterglows with echelle spectra (which show a high number of foreground absorbing systems) and those without, reveals no indication that the former are statistically significantly more luminous. Furthermore, we propose the existence of an upper ceiling on afterglow luminosities and study the luminosity distribution at early times, which was not accessible before the advent of the Swift satellite. Most GRBs feature afterglows that are dominated by the forward shock from early times on. Finally, we present the first indications of a class of long GRBs, which form a bridge between the typical high-luminosity, high-redshift events and nearby low-luminosity events (which are also associated with spectroscopic supernovae) in terms of energetics and observed redshift distribution, indicating a continuous distribution overal