All-sky search for gravitational-wave bursts in the second joint LIGO-Virgo run

We present results from a search for gravitational-wave bursts in the data collected by the LIGO and Virgo detectors between July 7, 2009 and October 20, 2010: data are analyzed when at least two of the three LIGO-Virgo detectors are in coincident operation, with a total observation time of 207 days. The analysis searches for transients of duration < 1 s over the frequency band 64-5000 Hz, without other assumptions on the signal waveform, polarization, direction or occurrence time. All identified events are consistent with the expected accidental background. We set frequentist upper limits on the rate of gravitational-wave bursts by combining this search with the previous LIGO-Virgo search on the data collected between November 2005 and October 2007. The upper limit on the rate of strong gravitational-wave bursts at the Earth is 1.3 events per year at 90% confidence. We also present upper limits on source rate density per year and Mpc^3 for sample populations of standard-candle sources. As in the previous joint run, typical sensitivities of the search in terms of the root-sum-squared strain amplitude for these waveforms lie in the range 5 10^-22 Hz^-1/2 to 1 10^-20 Hz^-1/2. The combination of the two joint runs entails the most sensitive all-sky search for generic gravitational-wave bursts and synthesizes the results achieved by the initial generation of interferometric detectors.Comment: 15 pages, 7 figures: data for plots and archived public version at https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=70814&version=19, see also the public announcement at http://www.ligo.org/science/Publication-S6BurstAllSky

Bringing up baby : representations of lone motherhood in modern popular culture

This thesis explores media representations of single mothers, and considers how one segment of the audience interprets the messages and ideologies embedded within texts, in relation to their own experiences and perceptions. It combines textual analysis of selected texts from popular television and film with empirical data collected during seminars conducted with groups of teenage, female college students and young single mothers. The texts studied were chosen from television soap opera and situation comedy (both of which deal mainly with family relationships and family situations) and popular, modem Hollywood films; three areas I considered to be central in helping me to gain an understanding of how the media construct meanings and messages for audiences in a form and style designed for repetition and unambiguity, to create easy understanding for audiences, even when they are actually complex and contradictory. The research groups were made up of young women aged between 16 and 20, from a variety of social and ethnic backgrounds. The fieldwork was conducted over a period of several weeks over the five year research period, and used with the case-study texts from contemporary popular culture. The data collected suggests that, beneath the increasingly diverse representations of single mothers in popular culture, media texts tend to define and represent single mothers generally as incomplete, lacking and/or deviant in comparison to ‘normal’ motherhood. However, the young audience members with whom I worked, used the parameters of their own experience and knowledge to simultaneously engage with and distance themselves from the seemingly entrenched ideologies embedded within the texts. As a result it seems that despite the essentially negative representations that continue to dominate media stereotypes of single mothers, young female viewers remain generally aware of and distanced from the messages being transmitted.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Optical observations of the BepiColombo spacecraft as a proxy for a potential threatening asteroid

We present the results of our ground-based astrometric observation campaign of BepiColombo during its Earth fly-by on 2020 April 10. The observational circumstances induced by the fly-by geometry made this event an excellent proxy for a close fly-by or an imminent impact of a natural body with a diameter of a few meters, with the added benefit of having a ground-truth orbit (from radio tracking) to compare with our purely optical orbit determination.The work of TSR was carried out through grant APOSTD/2019/046 by Generalitat Valenciana (Spain). This work was supported by the MINECO (Spanish Ministry of Economy) through grant RTI2018-095076-B-C21 (MINECO/FEDER, UE)

Shape and spin determination of Barbarian asteroids

Context. The so-called Barbarian asteroids share peculiar, but common polarimetric properties, probably related to both their shape and composition. They are named after (234) Barbara, the first on which such properties were identified. As has been suggested, large scale topographic features could play a role in the polarimetric response, if the shapes of Barbarians are particularly irregular and present a variety of scattering/incidence angles. This idea is supported by the shape of (234) Barbara, that appears to be deeply excavated by wide concave areas revealed by photometry and stellar occultations. Aims. With these motivations, we started an observation campaign to characterise the shape and rotation properties of Small Main-Belt Asteroid Spectroscopic Survey (SMASS) type L and Ld asteroids. As many of them show long rotation periods, we activated a worldwide network of observers to obtain a dense temporal coverage. Methods. We used light-curve inversion technique in order to determine the sidereal rotation periods of 15 asteroids and the convergence to a stable shape and pole coordinates for 8 of them. By using available data from occultations, we are able to scale some shapes to an absolute size. We also study the rotation periods of our sample looking for confirmation of the suspected abundance of asteroids with long rotation periods. Results. Our results show that the shape models of our sample do not seem to have peculiar properties with respect to asteroids with similar size, while an excess of slow rotators is most probably confirmed.© 2017 ESO.N.P. acknowledges funding from the Portuguese FCT - Foundation for Science and Technology. CI-TEUC is funded by National Funds through FCT - Foundation for Science and Technology (project: UID/ Multi/00611/2013) and FEDER - European Regional Development Fund through COMPETE 2020 - Operational Programme Competitiveness and Internationalisation (project: POCI-01-0145-FEDER-006922). SARA observations were obtained under the Chilean Telescope Allocation Committee program CNTAC 2015B-4. P.H. acknowledges financial support from the Natural Sciences and Engineering Research Council of Canada, and thanks the staff of Cerro Tololo Inter-American Observatory for technical support. The work of A.M. was supported by grant no. 2014/13/D/ST9/01818 from the National Science Centre, Poland. The research of V.K. is supported by the APVV-15-0458 grant and the VVGS-2016-72608 internal grant of the Faculty of Science, P.J. Safarik University in Kosice. M.K. and O.E. acknowledge TUBITAK National Observatory for a partial support in using T100 telescope with project number 14BT100-648.Peer Reviewe