Exploring ‘events’ as an information systems research methodology

This paper builds upon existing research and commentary from a variety of disciplinary sources including Information Systems, Organisational and Management Studies, and the Social Sciences that focus upon the meaning, significance and impact of ‘events’ in both an organisational and a social sense. The aim of this paper is to define how the examination of the event is an appropriate, viable and useful Information Systems methodology. Our argument is that focusing on the ‘event’ enables the researcher to more clearly observe and capture the complexity, multiplicity and mundaneity of everyday lived experience. The use and notion of ‘event’ has the potential to reduce the methodological dilemmas associated with the micromanagement of the research process – an inherent danger of traditional and ‘virtual' ethnographic approaches. Similarly, this paper addresses the over-emphasis upon managerialist, structured and time-fixated praxis that is currently symptomatic of Information Systems research. All of these concerns are pivotal points of critique found within eventoriented literature. An examination of event-related theory within interpretative disciplines directs the focus of this paper towards the more specific realm of the ‘event scene’. The notion of the ‘event scene’ originated in the action based (and anti-academy) imperatives of the Situationists and emerged in an academic sense as critical situational analysis. Event scenes are a focus for contemporary critical theory where they are utilised as a means of representing theoried inquiry in order to loosen the restrictions that historical and temporally bound analysis imposes upon most interpretative approaches. The use of event scenes as the framework for critiquing established conceptual assumptions is exemplified by their use in CTheory. In this journal's version and articulation of the event scene poetry, commentary, multi-vocal narrative and other techniques are legitimated as academic forms. These various forms of multi-dimensional expression are drawn upon to enrich the understandings of the ‘event’, to extricate its meaning and to provide a sense of the moment from which the point of analysis stems. The objective of this paper is to advocate how Information Systems research can (or should) utilize an event scene oriented methodology

Pulse Profiles, Accretion Column Dips and a Flare in GX 1+4 During a Faint State

The Rossi X-ray Timing Explorer (RXTE) spacecraft observed the X-ray pulsar GX 1+4 for a period of 34 hours on July 19/20 1996. The source faded from an intensity of ~20 mCrab to a minimum of <~0.7 mCrab and then partially recovered towards the end of the observation. This extended minimum lasted ~40,000 seconds. Phase folded light curves at a barycentric rotation period of 124.36568 +/- 0.00020 seconds show that near the center of the extended minimum the source stopped pulsing in the traditional sense but retained a weak dip feature at the rotation period. Away from the extended minimum the dips are progressively narrower at higher energies and may be interpreted as obscurations or eclipses of the hot spot by the accretion column. The pulse profile changed from leading-edge bright before the extended minimum to trailing-edge bright after it. Data from the Burst and Transient Source Experiment (BATSE) show that a torque reversal occurred <10 days after our observation. Our data indicate that the observed rotation departs from a constant period with a Pdot/P value of ~-1.5% per year at a 4.5 sigma significance. We infer that we may have serendipitously obtained data, with high sensitivity and temporal resolution about the time of an accretion disk spin reversal. We also observed a rapid flare which had some precursor activity, close to the center of the extended minimum.Comment: 19 pages, 6 figures, accepted for publication in Astrophysical Journal (tentatively scheduled for vol. 529 #1, 20 Jan 2000

The optical counterpart of SAX J1808.4-3658, the transient bursting millisecond X-ray pulsar

A set of CCD images have been obtained during the decline of the X-ray transient SAX J1808.4-3658 during April-June 1998. The optical counterpart has been confirmed by several pieces of evidence. The optical flux shows a modulation on several nights which is consistent with the established X-ray binary orbit period of 2 hours. This optical variability is roughly in antiphase with the weak X-ray modulation. The source mean magnitude of V=16.7 on April 18 declined rapidly after April 22. From May 2 onwards the magnitude was more constant at around V=18.45 but by June 27 was below our sensitivity limit. The optical decline precedes the rapid second phase of the X-ray decrease by 3 +/- 1 days. The source has been identified on a 1974 UK Schmidt plate at an estimated magnitude of ~20. The nature of the optical companion is discussed.Comment: 5 pages, 3 figures; published in MNRAS, March 15th 199

Accretion column eclipses in the X-ray pulsars GX 1+4 and RX J0812.4-3114

Sharp dips observed in the pulse profiles of three X-ray pulsars (GX 1+4, RX J0812.4-3114 and A 0535+26) have previously been suggested to arise from partial eclipses of the emission region by the accretion column occurring once each rotation period. We present pulse-phase spectroscopy from Rossi X-ray Timing Explorer satellite observations of GX 1+4 and RX J0812.4-3114 which for the first time confirms this interpretation. The dip phase corresponds to the closest approach of the column axis to the line of sight, and the additional optical depth for photons escaping from the column in this direction gives rise to both the decrease in flux and increase in the fitted optical depth measured at this phase. Analysis of the arrival time of individual dips in GX~1+4 provides the first measurement of azimuthal wandering of a neutron star accretion column. The column longitude varies stochastically with standard deviation 2-6 degrees depending on the source luminosity. Measurements of the phase width of the dip both from mean pulse profiles and individual eclipses demonstrates that the dip width is proportional to the flux. The variation is consistent with that expected if the azimuthal extent of the accretion column depends only upon the Keplerian velocity at the inner disc radius, which varies as a consequence of the accretion rate Mdot.Comment: 7 pages, 5 figures, accepted by MNRAS. Included reference

From Prosumer to “Prodesigner”: Participatory News Consumption

New democratic participation forms and collaborative productions of diverse audiences have emerged as a result of digital innovations in the online access to and consumption of news. The aim of this paper is to propose a conceptual framework based on the possibilities of Web 2.0. Outlining the construction of a “social logic”, which combines computer and communicative logics, the conceptual framework is theoretically built to explore the evolution of news consumption from a pure circulation of designed products towards a global conversation of proactive news designers. Then, the framework was tested using an empirical database built by the Pew Research Centre, which investigates the future of the news industry, through a large-scale survey with adults. Results show significant differences (by age, gender and educational level) in the forms of participation, access and consumption of news. However, whilst immersed in the culture of Web 2.0 there is a low-level of user participation in news production; far from being proactive news designers, findings suggest that citizens still located in the lower participatory levels of our conceptual framework. Conclusions suggest there is a need for media education providers to carry out training initiatives according to the social logic possibilities through proposed guidelines

A 4% Geometric Distance to the Galaxy NGC4258 from Orbital Motions in a Nuclear Gas Disk

The water maser in the mildly active nucleus in the nearby galaxy NGC4258 traces a thin, nearly edge-on, subparsec-scale Keplerian disk. Using the technique of very long baseline interferometry, we have detected the proper motions of these masers as they sweep in front of the central black hole at an orbital velocity of about 1100 km/s. The average maser proper motion of 31.5 microarcseconds per year is used in conjunction with the observed acceleration of the masers to derive a purely geometric distance to the galaxy of 7.2 +- 0.3 Mpc. This is the most precise extragalactic distance measured to date, and, being independent of all other distance indicators, is likely to play an important role in calibrating the extragalactic distance scale.Comment: 11 pages, 3 figures. Accepted for publication in Natur

Detection of a Hard Tail in the X-ray Spectrum of the Z Source GX 349+2

We present the results of a BeppoSAX observation of the Z source GX 349+2 covering the energy range 0.1-200 keV. The presence of flares in the light curve indicates that the source was in the flaring branch during the BeppoSAX observation. We accumulated energy spectra separately for the non-flaring intervals and the flares. In both cases the continuum is well described by a soft blackbody ($k T_{BB} \sim 0.5$ keV) and a Comptonized spectrum corresponding to an electron temperature of $k T_e \sim 2.7$ keV, optical depth $\tau \sim 10$ (for a spherical geometry), and seed photon temperature of $k T_W \sim 1$ keV. All temperatures tend to increase during the flares. In the non-flaring emission a hard tail dominates the spectrum above 30 keV. This can be fit by a power law with photon index $\sim 2$, contributing $\sim 2$ of the total source luminosity over the BeppoSAX energy range. A comparison with hard tails detected in some soft states of black hole binaries suggests that a similar mechanism could originate these components in black hole and neutron star systems.Comment: 15 pages, including 8 figures, to appear in Ap

A deep Chandra, VLA and Spitzer IRAC study of the very low luminosity nucleus of the elliptical NGC821

The relatively nearby (distance=24.1 Mpc) elliptical galaxy NGC821 hosts an extreme example of a quiescent central massive black hole, for which deep Chandra observations revealed a nuclear source for the first time (with L(2-10 keV)/L_Edd ~ 3.6X10^{-8}). We present here a multiwavelength study of this nucleus, including VLA observations that detect a radio counterpart to the Chandra nuclear source at 1.4 GHz, with a flux density of 127 $\mu$m and possibly a flat spectral shape; we also consider new Spitzer IRAC observations and archival HST images. With these data we discuss possible scenarios for the accretion modalities of the sole material that is available for fuelling, i.e., the stellar mass losses steadily replenishing the circumnuclear region. The final stages of accretion could be radiatively inefficient and coupled to a compact nuclear jet/outfow. The stellar mass losses could instead end up in a standard disc only if a Compton-thick AGN is present. Two extended sources detected by Chandra close to the nucleus could be due to several unresolved knots in a jet. If a jet is present, though, its kinetic energy would be only a very small fraction of the energy associated with the rest mass of the material being accreted. Starformation close to the nucleus is not shown by the available data. Deeper NICMOS, radio and far-IR observations should further constrain the accretion process.Comment: 32 pages, 4 figures; minor changes; accepted for publication in ApJ. This is the companion paper of astro-ph/070163