A Search for Technosignatures Around 11,680 Stars with the Green Bank Telescope at 1.15-1.73 GHz

We conducted a search for narrowband radio signals over four observing sessions in 2020-2023 with the L-band receiver (1.15-1.73 GHz) of the 100 m diameter Green Bank Telescope. We pointed the telescope in the directions of 62 TESS Objects of Interest, capturing radio emissions from a total of ~11,680 stars and planetary systems in the ~9 arcminute beam of the telescope. All detections were either automatically rejected or visually inspected and confirmed to be of anthropogenic nature. In this work, we also quantified the end-to-end efficiency of radio SETI pipelines with a signal injection and recovery analysis. The UCLA SETI pipeline recovers 94.0% of the injected signals over the usable frequency range of the receiver and 98.7% of the injections when regions of dense RFI are excluded. In another pipeline that uses incoherent sums of 51 consecutive spectra, the recovery rate is ~15 times smaller at ~6%. The pipeline efficiency affects calculations of transmitter prevalence and SETI search volume. Accordingly, we developed an improved Drake Figure of Merit and a formalism to place upper limits on transmitter prevalence that take the pipeline efficiency and transmitter duty cycle into account. Based on our observations, we can state at the 95% confidence level that fewer than 6.6% of stars within 100 pc host a transmitter that is detectable in our search (EIRP > 1e13 W). For stars within 20,000 ly, the fraction of stars with detectable transmitters (EIRP > 5e16 W) is at most 3e-4. Finally, we showed that the UCLA SETI pipeline natively detects the signals detected with AI techniques by Ma et al. (2023).Comment: 22 pages, 9 figures, submitted to AJ, revise

On guilt and the depoliticization of downsizing practices

The purpose of this paper is to provide a theoretical conceptualisation of guilt and the depoliticization of downsizing practices. We begin with a critical review of the relevant management literature aiming to establish the discursive normalization and individualization of (un)employment. We then use secondary sources to reflect on the downsizing process. A process that, as we argue, is distinguished into three separate but interconnected phases: corporate memos (phase 1), termination scripts (phase 2), and the role of outplacement services (phase 3). By examining this process our aim is to point to the mechanisms through which downsizing practices are neutralized and depoliticized. This is a conceptual work that provides a systematic overview of the existing management literature on downsizing and guilt. Use of other secondary sources (corporate memos and termination scripts) are also employed to draw links between the discursive normalisation of downsizing as identified in the relevant literature and the specific organisational processes and practices implemented by corporations during downsizing. We identify common ideas and themes that cut across the relevant literature and the secondary sources and aim to offer a theoretical conceptualisation of guilt and the depoliticization of downsizing practices. This paper argues that downsizing discourses and practices contribute to feelings of personal responsibility and self-blame, reinforcing an individualistic understanding of work and unemployment that excludes more structural ones, and that it helps in reproducing the existing structures of power. Our study recognises that employees’ reactions are not only unpredictable but also constantly evolving, depending on personal and social circumstances. We also recognise that our work is based on secondary sources much of which talk about practices in US companies, and thus we are and should be cautious of generalisations. We hope however that we will encourage further empirical research, particularly among organization studies and critical management scholars, on downsizing practices and guilt. For our part, we have tried to offer a critical reflection on how guilt is produced through corporate discourses and practices, and we believe that further empirical investigation on the three phases of the downsizing process (as identified in our work) and the lived experience of (un)employment is needed. As corporate downsizing discourses and practices frame (un)employment in strictly individualist and behavioural terms, we wish to emphasize the need for further theoretical investigation and political contestation. We therefore hope that our work will contribute to the relevant literature on downsizing practices and open up the discussions around layoff policies and the structural conditions of (un)employment. The paper shows that downsizing practices and feelings of guilt are strongly linked to and exemplify the ‘individualization’ of social and political issues such as work and unemployment. We suggest that individualization signifies, in some sense, a retreat from organized collective resistance and mobilization based upon class and that the prevalence of the ideology of individualism (and its correlative, meritocracy), over alternative explanations and solutions to such public issues, helps in reproducing existing structures of power and inequity

On the costs of being small: Case evidence from Kenyan family farms

We analyse allocative efficiency of major input factors for farmers in Kenya

A Search for Technosignatures Around 11,680 Stars with the Green Bank Telescope at 1.15–1.73 GHz

Abstract: We conducted a search for narrowband radio signals over four observing sessions in 2020–2023 with the L-band receiver (1.15–1.73 GHz) of the 100 m diameter Green Bank Telescope. We pointed the telescope in the directions of 62 TESS Objects of Interest, capturing radio emissions from a total of ∼11,680 stars and planetary systems in the ∼9′ beam of the telescope. All detections were either automatically rejected or visually inspected and confirmed to be of anthropogenic nature. We also quantified the end-to-end efficiency of radio SETI pipelines with a signal injection and recovery analysis. The UCLA SETI pipeline recovers 94.0% of the injected signals over the usable frequency range of the receiver and 98.7% of the injections when regions of dense radio frequency interference are excluded. In another pipeline that uses incoherent sums of 51 consecutive spectra, the recovery rate is ∼15 times smaller at ∼6%. The pipeline efficiency affects calculations of transmitter prevalence and SETI search volume. Accordingly, we developed an improved Drake figure of merit and a formalism to place upper limits on transmitter prevalence that take the pipeline efficiency and transmitter duty cycle into account. Based on our observations, we can state at the 95% confidence level that fewer than 6.6% of stars within 100 pc host a transmitter that is continuously transmitting a narrowband signal with an equivalent isotropic radiated power (EIRP) > 1013 W. For stars within 20,000 ly, the fraction of stars with detectable transmitters (EIRP > 5 × 1016 W) is at most 3 × 10−4. Finally, we showed that the UCLA SETI pipeline natively detects the signals detected with AI techniques by Ma et al