Search

Full list of authors: Aivazyan, V; Almualla, M.; Antier, S.; Baransky, A.; Barynova, K.; Basa, S.; Bayard, F.; Beradze, S.; Berezin, D.; Blazek, M.; Boutigny, D.; Boust, D.; Broens, E.; Burkhonov, O.; Cailleau, A.; Christensen, N.; Cejudo, D.; Coleiro, A.; Coughlin, M. W.; Datashvili, D.; Dietrich, T.; Dolon, F.; Ducoin, J-G; Duverne, P-A; Marchal-Duval, G.; Galdies, C.; Granier, L.; Godunova, V; Gokuldass, P.; Eggenstein, H. B.; Freeberg, M.; Hello, P.; Inasaridze, R.; Ishida, E. E. O.; Jaquiery, P.; Kann, D. A.; Kapanadze, G.; Karpov, S.; Kiendrebeogo, R. W.; Klotz, A.; Kneip, R.; Kochiashvili, N.; Kou, W.; Kugel, F.; Lachaud, C.; Leonini, S.; Leroy, A.; Leroy, N.; Su, A. Le Van; Marchais, D.; Midavaine, T.; Moeller, A.; Morris, D.; Natsvlishvili, R.; Navarete, F.; Noysena, K.; Nissanke, S.; Noonan, K.; Orange, N. B.; Peloton, J.; Popowicz, A.; Pradier, T.; Prouza, M.; Raaijmakers, G.; Rajabov, Y.; Richmond, M.; Romanyuk, Ya; Rousselot, L.; Sadibekova, T.; Serrau, M.; Sokoliuk, O.; Song, X.; Simon, A.; Stachie, C.; Taylor, A.; Tillayev, Y.; Turpin, D.; Vardosanidze, M.; Vlieghe, J.; Tosta e Melo, I; Wang, X. F.; Zhu, J., We present our follow-up observations with GRANDMA of transient sources revealed by the Zwicky Transient Facility (ZTF). Over a period of six months, all ZTF alerts were examined in real time by a dedicated science module implemented in the Fink broker, which will be used in filtering of transients discovered by the Vera C. Rubin Observatory. In this article, we present three selection methods to identify kilonova candidates. Out of more than 35 million alerts, a hundred sources have passed our selection criteria. Six were then followed-up by GRANDMA (by both professional and amateur astronomers). The majority were finally classified either as asteroids or as supernovae events. We mobilized 37 telescopes, bringing together a large sample of images, taken under various conditions and quality. To complement the orphan kilonova candidates, we included three additional supernovae alerts to conduct further observations during summer 2021. We demonstrate the importance of the amateur astronomer community that contributed images for scientific analyses of new sources discovered in a magnitude range r′ = 17 − 19 mag. We based our rapid kilonova classification on the decay rate of the optical source that should exceed 0.3 mag d−1. GRANDMA’s follow-up determined the fading rate within 1.5 ± 1.2 d post-discovery, without waiting for further observations from ZTF. No confirmed kilonovae were discovered during our observing campaign. This work will be continued in the coming months in the view of preparing for kilonova searches in the next gravitational-wave observing run O4. © 2022 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society., SA and CL acknowledge the financial support of the Programme National Hautes Energies (PNHE). SA acknowledges the financial support of CNES. SA is grateful for financial support from the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) through the VIDI (PI: Nissanke). SA dedicates her contribution to Rayan Ouram, who is a source of inspiration for bravity and humanity for GRANDMA. DT acknowledges the financial support of CNES post-doctoral program. UBAI acknowledges support from the Ministry of Innovative Development through projects FA-Atech-2018-392 and VA-FA-F-2-010. RI acknowledges Shota Rustaveli National Science Foundation (SRNSF) grant No - RF/18-1193. TAROT. has been built with the support of the Institut National des Sciences de l’Univers, CNRS, France. MP, SK, and MM are supported by European Structural and Investment Fund and the Czech Ministry of Education, Youth and Sports (Projects CZ.02.1.01/0.0/0.0/16_013/0001403, CZ.02.1.01/0.0/0.0/18_046/0016007 and CZ.02.1.01/0.0/0.0/15_003/0000437). The FRAM telescope is also supported by the Czech Ministry of Education, Youth and Sports (projects LM2015046, LM2018105, LTT17006). NBO and DM acknowledge financial support from NASA MUREP MIRO award 80NSSC21M0001, NASA EPSCoR award 80NSSC19M0060, and NSF EiR award 1901296. PG acknowledges financial support from NSF EiR award 1901296. DAK acknowledges support from Spanish National Research Project RTI2018-098104-J-I00 (GRBPhot) XW is supported by the National Science Foundation of China (NSFC grants 12033003 and 11633002), the Scholar Program of Beijing Academy of Science and Technology (DZ:BS202002), and the Tencent Xplorer Prize. The work of FN is supported by NOIRLab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. The GRANDMA consortium thank the amateur participants to the kilonova-catcher program. The kilonova-catcher program is supported by the IdEx Université de Paris, ANR-18-IDEX-0001. This research made use of the cross-match service provided by CDS, Strasbourg. MC acknowledges support from the National Science Foundation with grant numbers PHY-2010970 and OAC-2117997. GR acknowledges financial support from the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) through the Projectruimte and VIDI grants (PI: Nissanke). Thanks to the National Astronomical Research Institute of Thailand (Public Organization), based on observations made with the Thai Robotic Telescope under program ID TRTC08D_005 and TRTC09A_002. S., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

Context. EE Cep is one of few eclipsing binary systems with a dark, dusty disk around an invisible object similar to {\epsilon} Aur. The system is characterized by grey and asymmetric eclipses every 5.6 yr, with a significant variation in their photometric depth, ranging from ~ 0 m .5 to ~ 2 m .0. Aims. The main aim of the observational campaign of the EE Cep eclipse in 2014 was to test the model of disk precession (Galan et al. 2012). We expected that this eclipse would be one of the deepest with a depth of ~ 2 m .0. Methods. We collected multicolor observations from almost 30 instruments located in Europe and North America. This photometric data covers 243 nights during and around the eclipse. We also analyse the low- and high-resolution spectra from several instruments. Results. The eclipse was shallow with a depth of 0 m .71 in V-band. The multicolor photometry illustrates small color changes during the eclipse with a total amplitude of order ~ +0 m . 15 in B-I color index. The linear ephemeris for this system is updated by including new times of minima, measured from the three most recent eclipses at epochs E = 9, 10 and 11. New spectroscopic observations were acquired, covering orbital phases around the eclipse, which were not observed in the past and increased the data sample, filling some gaps and giving a better insight into the evolution of the H {\alpha} and NaI spectral line profiles during the primary eclipse. Conclusions. The eclipse of EE Cep in 2014 was shallower than expected 0 m .71 instead of ~ 2 m . 0. This means that our model of disk precession needs revision., Comment: 10 pages, 13 figures, 29 tables in appendix, submited to Astronomy & Astrophysics

The polarization anisotropy of Lyman-α fluorescence in the photodissociation of the doubly excited states of H2 has been measured in the 27–38 eV energy range. It has been calculated taking into account the dissociation probabilities of the various molecular states involved in the process and the depolarization due to collisional effects. The agreement between experiment and theory is very good; it shows the importance of interferences and gives confidence in the analysis of the process. The fluorescence polarization anisotropy has been calculated classically in the case of a dissociation leading to H(2pπ) + H(2pσ) excited fragments.

The de-excitation cross sections of H atoms colliding with molecular hydrogen were determined in the velocity range of 2-. At a mean velocity of the de-excitation cross sections are , and . The velocity dependence of the de-excitation cross sections observed in the experiment agrees with the quadrupole-H dipole interaction and with the quantum character of the molecular rotation.

Die Sensitivitat der Hirnperfusionsszintigraphie liegt am niedrigsten. Hohe Sensitivitat zeigen die Doppler-Sonographie der orbitalen Gefase in der Findung hochgradiger, die Dynamometrie in der Erkennung hoch- und mittelgradiger Stenosen, wenn die verdachtigen ODM-Befunde mit einbezogen werden. Als sinnvolle Verfahrensweise in der Diagnostik stenosierender Carotisprozesse sehen wir die Kombination Dynamometrie/Doppler-Sonographie an, da sie erlaubt, mittel- und hochgradige Verschlusprozesse der A. carotis mit hoher Zuverlassigkeit aufzudecken.