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Abstract We present coordinated observations of GRB 170202A carried out by the Zadko and the Virgin Island Robotic Telescopes. The observations started 59 s after the event trigger, and provided nearly continuous coverage for two days, due to the unique locations of these telescopes. We clearly detected an early rise in optical emission, followed by late optical flares. By complementing these data with archival observations, we show that GRB 170202A is well described by the standard fireball model if multiple reverse shocks are taken into account. Its fireball is evidenced as expanding within a constant-density interstellar medium, with most burst parameters being consistent with the usual ranges found in the literature. The electron and magnetic energy parameters ( ϵ e , ϵ B ) are orders of magnitude smaller than the commonly assumed values. We argue that the global fit of the fireball model achieved by our study should be possible for any burst, pending the availability of a sufficiently comprehensive data set. This conclusion emphasizes the crucial importance of coordinated observation campaigns of gamma-ray bursts, such as the one central to this work, to answer outstanding questions about the underlying physics driving these phenomena. 

ABSTRACT We present multiwavelength spectral and temporal variability analysis of PKS 0027-426 using optical griz observations from Dark Energy Survey between 2013 and 2018 and VEILS Optical Light curves of Extragalactic TransienT Events (VOILETTE) between 2018 and 2019 and near-infrared (NIR) JKs observations from Visible and Infrared Survey Telescope for Astronomy Extragalactic Infrared Legacy Survey (VEILS) between 2017 and 2019. Multiple methods of cross-correlation of each combination of light curve provides measurements of possible lags between optical–optical, optical–NIR, and NIR–NIR emission, for each observation season and for the entire observational period. Inter-band time lag measurements consistently suggest either simultaneous emission or delays between emission regions on time-scales smaller than the cadences of observations. The colour–magnitude relation between each combination of filters was also studied to determine the spectral behaviour of PKS 0027-426. Our results demonstrate complex colour behaviour that changes between bluer when brighter, stable when brighter, and redder when brighter trends over different time-scales and using different combinations of optical filters. Additional analysis of the optical spectra is performed to provide further understanding of this complex spectral behaviour. 

Chatbots have proven to be effective tools in the fields of marketing, sales, customer relationship management and many other applications. This research explores the opportunities for chatbots to contribute to the promotion of scientific research and initiatives. The Etelman Observatory Research Center of the University of the Virgin Islands (UVI) houses the Virgin Islands Robotic Telescope (VIRT), a fully-automated, robotically controlled, and queue-driven 0.5 meter research grade telescope. The Etelman Observatory's mission is to be a world-class research and education center that engages with the local community through various outreach activities in all its initiatives. Given the challenges of physical presence during the COVID-19 crisis, Observatory personnel decided to adopt chatbot technology to engage interested parties over the Internet in its key scientific instrument for astrophysics -- VIRT. VIRTBot is a chatbot designed to provide VIRT with a voice that interested community members can engage with directly. The team implemented VIRTBot with Amazon Web Services (AWS) technologies in the cloud and deployed the solution online. Volunteers were surveyed about their knowledge of the Observatory's activities after reviewing either an FAQ or engaging with VIRTBot. The study demonstrated that the FAQ outperformed VIRTBot in terms of knowledge dissemination, but VIRTBot outperformed the FAQ in measures of interest and engagement. Our research suggests that, under the right conditions, chatbots improve engagement over traditional web resources in promoting STEM educational initiatives to the public. Keywords: Chatbot, Amazon Web Services 

Kepler data for three SRS: stars, V616 Lyrae, V607 Lyrae, and V621 Lyrae, were analyzed to study their period structure. Two of the stars had confirmed SRS light curve characteristics. V616 Lyr shows two strong periods at 16.91 days and 8.18 days. V607 Lyr shows one strong period at 13.55 days. V616 Lyr and V607 Lyr also display amplitude changes common to the SR stars. Variability was not detected for V621 Lyr. Evidence for solar-like oscillations in V616 Lyr is presented. 

ABSTRACT GRANDMA (Global Rapid Advanced Network Devoted to the Multi-messenger Addicts) is a network of 25 telescopes of different sizes, including both photometric and spectroscopic facilities. The network aims to coordinate follow-up observations of gravitational-wave (GW) candidate alerts, especially those with large localization uncertainties, to reduce the delay between the initial detection and the optical confirmation. In this paper, we detail GRANDMA’s observational performance during Advanced LIGO/Advanced Virgo Observing Run 3 (O3), focusing on the second part of O3; this includes summary statistics pertaining to coverage and possible astrophysical origin of the candidates. To do so, we quantify our observation efficiency in terms of delay between GW candidate trigger time, observations, and the total coverage. Using an optimized and robust coordination system, GRANDMA followed-up about 90 per cent of the GW candidate alerts, that is 49 out of 56 candidates. This led to coverage of over 9000 deg2 during O3. The delay between the GW candidate trigger and the first observation was below 1.5 h for 50 per cent of the alerts. We did not detect any electromagnetic counterparts to the GW candidates during O3, likely due to the very large localization areas (on average thousands of degrees squares) and relatively large distance of the candidates (above 200 Mpc for 60 per cent of binary neutron star, BNS candidates). We derive constraints on potential kilonova properties for two potential BNS coalescences (GW190425 and S200213t), assuming that the events’ locations were imaged.