Visokoenergijsko gama-zračenje pulsara i maglica pulsarovog vjetra opažanih teleskopima MAGIC

A pulsar wind nebula (PWN) is a system with a central rotating object, a pulsar, which powers a surrounding nebula. This complex system is observed to emit radiation throughout the electromagnetic spectrum, from radio to gamma rays. In this thesis I explored the gamma-ray emission from pulsars, their respective nebulae and one PWN candidate at very high energies (VHE, E > 100 GeV) using the Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) telescopes. At the beginning of this research, only one pulsar, the Crab pulsar, was known to emit at VHE, challenging the theoretical models. The observed electromagnetic radiation from the pulsar-nebula system implies the presence of a mechanism that accelerates charged particles to ultra-relativistic energies. However, this mechanism is poorly understood, thus VHE pulsar observations are relevant not only as information for emission modelling but also as a contribution for better characterization of fundamental properties of these complex astrophysical systems. The MAGIC telescopes, with its novel trigger especially developed for pulsar obser- vation, is the most suitable instrument to search for new VHE pulsars. In this thesis, I present the observations and analysis of two galactic sources: Crab (PSR J0534+2200) and Dragonfly (PSR J2021+3651) pulsars. For the well-known and previously detected Crab pulsar, the anal- ysis shows the expected results and is used as a performance check of the method. The same method is then used to search for VHE emission from the Dragonfly pulsar, proposed as a very likely VHE pulsar candidate due to its similar characteristics to the Crab pulsar. I found no significant pulsed emission from Dragonfly pulsar in low Eγ-range (50 GeV 200 GeV), only upper limits were derived. However, with the same set of data, the Dragonfly nebula surrounding the pulsar was detected. I also present the study of the unidentified TeV source, HESS J1858+020, that was put forward as a relic PWN candidate using the archival data collected from the MAGIC telescopes where this source was relatively far from the centre of the camera implying a decrease in detection sensitivity. Nevertheless, the source was detected, source extension estimated and the spectrum between 300 GeV and 10 TeV was constrained, but morphological or other details were not discerned. Neither the PWN scenario could be refuted nor confirmed. Overall, detailed studies of the VHE gamma-ray emission from pulsars and nebulae seem more challenging than expected, and longer observations are needed for pulsed detection or for morphological characterization of nebulae. The next-generation Cherenkov telescope array (CTA) with an order of magnitude better sensitivity and with 1 arcminute resolution, will certainly allow detailed morphological and spectral studies of this kind of source. Furthermore, I also studied a faint component of the Galactic diffuse synchrotron emission at low-radio frequencies by using multiple polarimetric observations with the LOw Frequency ARray (LOFAR). Before stacking them, these observations first needed to be corrected for the Faraday rotation in the Earth’s ionosphere, otherwise, the observed polarized emission may be either partially or in exceptional cases fully depolarized. I used the observed polarized diffuse synchrotron emission to characterize and additionally correct for the ionospheric Faraday rotation. After stacking twenty observations, the noise was reduced by ∼ √20, as expected. A higher signal-to-noise ratio achieved with this method enables a study of the faint component of the Galactic diffuse emission, which was not visible in a single reference observation. Moreover, the applied technique can also be used for studies of faint polarized sources, including pulsars.Glavna tema ovog rada je proučavanje visokoenergijskog gama-zračenja iz pulsara i maglica pulsarovog vjetra opažanih teleskopima MAGIC (engl. Major Atmospheric Gamma Imaging Cherenkov). Gama-astronomija proučava procese u svemiru koji se odvijaju u uvjetima ekstremno velikih energija i gustoća. Podrijetlo kozmičkog gama-zračenja vrlo visokih energija (100 GeV < E < 100 TeV) su netermički procesi koji nose informaciju o galaktičkim i izvangalaktičkim izvorima. Galaktički izvori su ostaci supernova (engl. supernova remnants), pulsari, maglice pulsarovog vjetra (engl. pulsar wind nebulae), dvojni gama-sustavi (engl. binary systems) te magnetari, dok su izvangalaktički izvori npr. aktivne galaktičke jezgre, provale gama-zračenja (engl. gamma ray burst, GRB) i tamna tvar - koja je potencijalno i galaktički izvor. U prošlom desetljeću, opažanjima opservatorija na energijama u području TeV (MAGIC, VERITAS, HESS, Milagro) otkriven je velik broj izvora u galaktičkoj ravnini, među kojima su maglice pulsarovog vjetra dominantna populacij

The school pedagogue and the function of pedagogical school management

Predmet istraživanja je uloga školskog pedagoga u odnosu na funkciju pedagoškog vođenja škole i kompetencije pedagoga potrebne za pedagoško vođenje. U istraživanju je sudjelovalo 211-ero ispitanika, a ispitivani su: pozitivni uvjeti rada, motivacija, kvaliteta rada, poticanje na timski rad, poticanje profesionalnog razvitka, zadovoljstvo odnosima u radnoj okolini, suradnja s roditeljima i širom zajednicom te rad pedagoga kao pedagoškog voditelja i kompetencije pedagoga potrebne za pedagoško vođenje. Rezultati upućuju na zaključak da još treba raditi na motivaciji, kvalitetnim promjenama, poticanju profesionalnog razvitka i poticanju na timski rad u školama. Kompetencijski profil pedagoga istaknut je dobivenim kompetencijama školskog pedagoga potrebnim za pedagoško vođenje: odgovornost, komunikacijske vještine i savjetodavni rad, dosljednost u radu, poznavanje potreba učenika i nastavnika, poznavanje didaktičkih i metodičkih načela, analiza odgojno-obrazovnog rada, suradnja s nastavnicima i umijeće demokratskog pedagoškog vođenja.The subject of this research is the role of the school pedagogue in terms of pedagogical school management, and the competences that a pedagogue needs in order to carry out pedagogical management. The survey comprised 211 respondents, and the following was studied: positive working conditions, motivation, performance, encouragement of team work, encouragement of professional development, satisfaction with relations in the working environment, cooperation with parents and the wider community, the pedagogue’s work as a pedagogical manager, and the competences that a pedagogue needs for pedagogical management. The results lead to the conclusion that more work has to be done on motivation, quality changes, encouraging professional development and encouraging team work in schools. The competence profile of a pedagogue is defined through the obtained school pedagogue’s pedagogical management competences: responsibility, communication skills and counselling work, consistency, knowledge of the students’ and teachers’ needs, knowledge of didactical and methodological principles, analysis of educational work, cooperation with teachers, and the skill of democratic pedagogical management

Kompetencije stručnog suradnika pedagoga u suvremenoj pedagoškoj praksi

Suvremena pedagoška djelatnost pred stručne suradnike pedagoge postavlja velike izazove. Kompetencijski pristup sve se češće koristi u teoriji i praksi upravljanja ljudskim resursima. Stručni suradnik pedagog mora razviti specifične kompetencije kako bi kvalitetno obavljao profesionalne zadaće neposrednog odgojno-obrazovnog rada. Ključne kompetencije pedagogu su potrebne, između ostalog, zbog prepoznavanja potreba subjekata u odgoju i obrazovanju te unapređivanja odgojno-obrazovnog rada u cjelini. U ovom su radu prikazani rezultati ispitivanja poželjnih kompetencija stručnih suradnika pedagoga osnovnih i srednjih škola u neposrednom radu sa subjektima. Ispitivanje je provedeno na državnom stručnom skupu za stručne suradnike pedagoge osnovnih i srednjih škola, održanom 2010. godine u Primoštenu

Hibridna nastava i kvaliteta odgojno-obrazovnog rada u obrazovanju medicinskih sestara i tehničara

Zatvaranje odgojno-obrazovnih ustanova uzrokovano pandemijom bolesti COVID-19 postavilo je mnoge izazove u odgojno-obrazovnom radu. Pred nastavnike i stručne suradnike postavljeni su zahtjevi prilagodbe planiranja i provedbe odgojno-obrazovnog procesa, od uvođenja nastave na daljinu do upotrebe različitih digitalnih alata i platformi, a u cilju osiguravanja kontinuiteta i kvalitete odgojno-obrazovnog rada. Izraženije poteškoće javile su se u strukovnom dijelu kurikuluma, što se posebno odrazilo na obrazovanje medicinskih sestara i tehničara i provedbu nastavnih vježbi. No prednosti digitalizacije nastavnog procesa dovele su do intenzivnije primjene e-učenja, time i mogućnosti primjene hibridnog modela nastave. U ovom su radu prikazani rezultati pilot-istraživanja u kojem su ispitivani stavovi nastavnika i stručnih suradnika (koji rade u obrazovanju medicinskih sestara i tehničara) o mogućnostima i učinkovitosti primjene hibridnog modela nastave, utjecaju na kvalitetu cjelokupnog odgojno-obrazovnog rada kao i u provedbi vježbi u predmetima struke

Phase-resolved Crab pulsar measurements from 25 to 400 GeV with the MAGIC telescopes

We report on observations of the Crab pulsar with the MAGIC telescopes. Our data were taken in both monoscopic (> 25GeV) and stereoscopic (> 50GeV) observation modes. Two peaks were detected with both modes and phase-resolved energy spectra were calculated. By comparing with Fermi- LAT measurements, we find that the energy spectrum of the Crab pulsar does not follow a power law with an exponential cutoff, but has an additional hard component, extending up to at least 400 GeV. This suggests that the emission above 25 GeV is not dominated by curvature radiation, as suggested in the standard scenarios of the OG and SG models.Comment: 4 pages, 2 figures, Proc. TAUP 2011, submitted for publication in JCP