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Historical, Neo-, and Contemporary Avant-Gardes in East Central Europe: Transversal Artistic Strategies Beyond the Anthropocene
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Oxidative potential of atmospheric particles in Europe and exposure scenarios
No full textAtmospheric particulate matter (PM), a public health concern worldwide, is at present regulated according to its mass concentration. However, it is increasingly thought that mass concentration may not fully capture the physicochemical properties of PM linked to its health impact. Consequently, it has been suggested to further investigate the adequacy of this metric as an unequivocal indicator of PM health effects. The new European regulation on air quality introduced oxidative potential (OP) as a recommended parameter to be monitored at supersites, to explore further deciphering information about PM reactivity and health impacts. Here we use a database of almost 11500 OP measurements from 43 locations across parts of Europe that were analysed with the two most commonly used OP assays, OPAA and OPDTT, with a standardized protocol. We find high spatial variability of OP across Europe, strongly influenced by site type, such as urban or rural. Accounting for OP alongside PM mass suggests that further improvements in urban air quality may require consideration, particularly near roads, where volumetric OP of PM10 exceeds background levels by a factor of 2.4 to 3.1, depending on the assay used. Analysis of mitigation strategies shows that traffic is a key source to target for effectively reducing OP in cities, whereas comprehensive reductions in PM from both traffic and biomass burning are required to also meet World Health Organization mass guidelines. Although the epidemiological evidence for OP health impacts is still evolving, our findings may help inform the interpretation of future work
Proučevanje vesolja z gravitacijskim lečenjem v novi dobi teleskopskih pregledov neba
No full textGalaxy clusters can magnify supernovae through strong gravitational lensing, thereby creating multiple images of the same supernova. This phenomenon enables measurements of cosmological parameters, primarily the Hubble constant. Gravitationally lensed supernovae are intrinsically rare events, with fewer than ten discovered to date. In this thesis, we study the prospects for detecting strongly lensed supernovae behind galaxy clusters, with a focus on two upcoming observatories: the Vera C. Rubin Observatory (Rubin) and the Nancy Grace Roman Space Telescope (Roman).
We employed two approaches: one focusing on known multiply-imaged galaxies behind cluster fields, along with supernova rates specific to those galaxies, and another based on the expected number of multiply-imaged supernovae in a given volume behind a galaxy cluster. We collected all galaxy clusters in literature with multiply-imaged galaxies that have high-quality spectroscopic and photometric data for the first estimate approach, or a well constrained lens model for the second. We provide lensed supernova yield predictions for 46 clusters visible to Rubin, as well as for 9 observable by Roman’s High Latitude Time Domain Survey. In addition, we created a publicly available index of gravitational lensing models and publications on galaxy clusters. The index represents a comprehensive database of lensing models, including those not used in our work.
We predict that the number of multiply-imaged supernovae discovered by Rubin in its first three years of operation is 3.95±0.89 from the first approach, or 4.94±1.02 from the second. Based on recent proposed observing strategies for Roman’s High Latitude Time Domain Survey, the expected number of multiply-imaged supernovae ranges from 0.38±0.15 to 5.2±2.2, depending on the specific cluster observed. As the exact fields to be targeted by the survey remain a matter of discussion, we provide a recommendation for the field selection, that either the cluster MACS J0553.4-3342 or Abell 1758a should be observed by the survey to maximize the number of potential multiply-imaged supernova discoveries. We furthermore conclude that Rubin offers great prospects for detecting multiply-imaged supernovae, and that if adequate follow-up campaigns are conducted, these capabilities will enable precise measurements of cosmological parameters that are independent of conventional probes.Jate galaksij lahko zaradi močnega gravitacijskega lečenja ustvarijo več lečenih slik iste supernove, ki je posledično videti svetlejša. Ta pojav omogoča merjenje kozmoloških parametrov, predvsem Hubblove konstante. Gravitacijsko lečene supernove so redek pojav in so jih doslej odkrili manj kot deset. V tej disertaciji proučujemo obete za odkritje močno lečenih supernov za jatami galaksij s poudarkom na
dveh prihajajočih observatorijih: Observatoriju Vera C. Rubin (Rubin) in Vesoljskem Teleskopu Nancy Grace Roman (Roman).
Uporabili smo dva pristopa: prvi se je osredotočil na znane večkratno lečene galaksije za polji jat, skupaj s številom supernov, značilnim za te galaksije, drugi pa je temeljil na pričakovanem številu večkratno lečenih supernov v danem prostoru za jato galaksij. Za prvi pristop smo zbrali vse v literaturi navedene jate galaksij z večkratno lečenimi galaksijami, ki imajo kakovostne spektroskopske in fotometrične podatke, za drugi pristop pa dobro omejen model leč. Podajamo napovedi možnega števila lečenih supernov za 46 jat, ki so vidne z observatorija Rubin, in za 9 jat, ki jih bo opazoval pregled neba High Latitude Time Domain Survey na teleskopu Roman. Poleg tega smo ustvarili javno dostopen seznam modelov gravitacijskih leč in objav o jatah galaksij. Ta seznam predstavlja celovito zbirko podatkov o modelih leč, vključno s tistimi, ki niso bili uporabljeni v našem delu.
Pričakovano število večkratno lečenih supernov, ki jih bo observatorij Rubin odkril v prvih treh letih delovanja, je v prvem pristopu 3,95 ± 0,89 in v drugem 4,94 ± 1,02. Na podlagi nedavno predlaganih opazovalnih strategij pregleda neba High Latitude Time Domain Survey na teleskopu Roman je pričakovano število večkratno lečenih supernov od 0,38 ± 0,15 do 5,2 ± 2,2, odvisno od posamezne opazovane jate. Ker trenutno še potekajo razprave o točnih delih neba, na katere naj bi se ta pregled osredotočil, podajamo priporočilo, da naj vključuje opazovanje bodisi jate MACS J0553.4-3342 bodisi jate Abell 1758a, da bo odkril največje število večkratno lečenih supernov. Zaključujemo, da prinaša Rubin velike obete za odkrivanje večkratno lečenih supernov in da bodo ta odkritja, ob podpori ustreznih sledilnih opazovanj, omogočila natančne meritve kozmoloških parametrov, ki bodo neodvisne od običajnih metod
