Doppler factors, Lorentz factors and viewing angles for quasars, BL Lacertae objects and radio galaxies

We have calculated variability Doppler boosting factors, Lorentz factors, and viewing angles for a large sample of sources by using total flux density observations at 22 and 37 GHz and VLBI data. We decomposed the flux curves into exponential flares and determined the variability brightness temperatures of the fastest flares. By assuming the same intrinsic brightness temperature for each source, we calculated the Doppler boosting factors for 87 sources. In addition we used new apparent jet speed data to calculate the Lorentz factors and viewing angles for 67 sources. We find that all quasars in our sample are Doppler-boosted and that the Doppler boosting factors of BL Lacertae objects are lower than of quasars. The new Lorentz factors are about twice as high as in earlier studies, which is mainly due to higher apparent speeds in our analyses. The jets of BL Lacertae objects are slower than of quasars. There are some extreme sources with very high derived Lorentz factors of the order of a hundred. These high Lorentz factors could be real. It is also possible that the sources exhibit such rapid flares that the fast variations have remained undetected in monitoring programmes, or else the sources have a complicated jet structure that is not amenable to our simple analysis. Almost all the sources are seen in a small viewing angle of less than 20 degrees. Our results follow the predictions of basic unification schemes for AGN.Comment: 12 pages, 14 figures, Accepted for publication in A&

The role of perceived employer obligations in the interpretation of and reaction to expatriate compensation practices

Best Paper Award of EIASM's 3rd Reward Management Conference 2011 (RMC 2011)International audienceIn this paper I examine the relationship between expatriates' perceptions of their compensation package and their affective commitment. The results of this cross-sectional study amongst 263 Finnish expatriates suggest the mediating role of the employee's perceptions of fulfillment of their employer obligations. This leads to the consideration that employees systematically assess their total reward package, interpret and give meaning to these compensation signals in terms of fulfillment of perceived employer obligations and simultaneously re-adapt or adjust their attitudes at any moment thorough their exchange relationship. In addition, this study gives empirical support for some of Rousseau and Ho's (2000) theoretical arguments regarding psychological contract (PC) issues in compensation. Furthermore it provides evidence that three of the PC feature measures for employer obligations developed by Janssens, Sels and Van den Brande (2003) can be replicated. Finally the implications of these findings for future research are discussed

INTERNATIONALISM ANCHOR: CONSTRUCT OPERATIONALIZATION AND SCALE VALIDATION

The internationalism anchor describes individuals who are primarily excited by working in international task environment, who prefer developing their professional competencies in international settings, and search for new experiences by getting to know unfamiliar countries and different cultures (Suutari & Taka, 2004). This anchor is thought to lead the career choices of an increasing number of individuals nowadays. This in-progress research paper presents an operationalization of this construct and examines its validity and correlates.Career Anchor; Internationalism; Expatriates; Self-Initiated Expatriates;

Locating the gamma-ray emission site in Fermi/LAT blazars from correlation analysis between 37 GHz radio and gamma-ray light curves

We address the highly debated issue of constraining the gamma-ray emission region in blazars from cross-correlation analysis using discrete correlation function between radio and gamma-ray light curves. The significance of the correlations is evaluated using two different approaches: simulating light curves and mixed source correlations. The cross-correlation analysis yielded 26 sources with significant correlations. In most of the sources, the gamma-ray peaks lead the radio with time lags in the range +20 and +690 days, whereas in sources 1633+382 and 3C 345 we find the radio emission to lead the gamma rays by -15 and -40 days, respectively. Apart from the individual source study, we stacked the correlations of all sources and also those based on sub-samples. The time lag from the stacked correlation is +80 days for the whole sample and the distance travelled by the emission region corresponds to 7 pc. We also compared the start times of activity in radio and gamma rays of the correlated flares using Bayesian block representation. This shows that most of the flares at both wavebands start at almost the same time, implying a co-spatial origin of the activity. The correlated sources show more flares and are brighter in both bands than the uncorrelated ones.Comment: 15 pages, 8 figures and 4 tables. Published in MNRAS. Online-only Figure 6 is available as ancillary file with this submissio

Data Congruence in What They Say, Do and Feel: The Role of Researcher's Sensory Processing Sensitivity Trait

This is the author accepted manuscript. The final version is available from Emerald via the DOI in this recordThis chapter focusses on how qualitative research can capture the lived experiences of entrepreneurial individuals by exploring their subjective experiences. Traditional methods of data collection involve listening to what entrepreneurial individuals say and observing their actions, although particular attention to their feelings is often absent. To achieve data congruence and to gain a deeper understanding of their lived experiences, it is crucial to also take into consideration how they feel. This chapter will recount a confessional tale recorded during a recent field study in entrepreneurship that will shed light on the pivotal role that a researcher’s sensory processing sensitivity (SPS) trait can play during qualitative data collection in helping researchers becoming mindful of the feelings of entrepreneurial individuals, even when those feelings are not directly expressed by them. The introduction of the researcher’s SPS trait in promoting data congruence during qualitative data collection will be this chapter’s principal contribution

Perceived uncertainty and behavioral logic: Temporality and unanticipated consequences in the new venture creation process

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.In this study, drawing on effectuation theory, we combine analytical strategies for process data to examine inductively and theorize how founder teams' perceptions of uncertainty and behavioral logics develop during new venture creation processes. The results reveal four phases and suggest a possible evolution from a causal conditional relationship between perceived uncertainty and behavioral logics to an integrative relationship. We bring to light the notion of temporality and unanticipated consequences, discuss their central roles in perceived uncertainty, effectuation, and causation, and offer revelatory insights into why and when effectuation is used in relation to uncertainty and entrepreneurial action

Statistical analyses of long-term variability of AGN at high radio frequencies

We present a study of variability time scales in a large sample of Active Galactic Nuclei at several frequencies between 4.8 and 230 GHz. We investigate the differences of various AGN types and frequencies and correlate the measured time scales with physical parameters such as the luminosity and the Lorentz factor. Our sample consists of both high and low polarization quasars, BL Lacertae objects and radio galaxies. The basis of this work is the 22 GHz, 37 GHz and 87 GHz monitoring data from the Metsahovi Radio Observatory spanning over 25 years. In addition,we used higher 90 GHz and 230 GHz frequency data obtained with the SEST-telescope between 1987 and 2003. Further lower frequency data at 4.8 GHz, 8 GHz and 14.5 GHz from the University of Michigan monitoring programme have been used. We have applied three different statistical methods to study the time scales: The structure function, the discrete correlation function and the Lomb-Scargle periodogram. We discuss also the differences and relative merits of these three methods. Our study reveals that smaller flux density variations occur in these sources on short time scales of 1-2 years, but larger outbursts happen quite rarely, on the average only once in every 6 years. We do not find any significant differences in the time scales between the source classes. The time scales are also only weakly related to the luminosity suggesting that the shock formation is caused by jet instabilities rather than the central black hole.Comment: 19 pages, 12 figures, Accepted for publication in A&