Repository of University of Nova Gorica

Show document
A+ | A- | Help | SLO | ENG

Title:Space weather research with the Pierre Auger Observatory
Authors:ID Stanič, Samo (Mentor) More about this mentor... New window
ID Živec, Miha (Author)
ID Vorobiov, Serguei (Member of the commission for defense)
Files:.pdf Miha_Zivec.pdf (5,21 MB)
MD5: 3139BD5107A6E51DA220EF45026FDEA2
 
Language:English
Work type:Master's thesis/paper
Typology:2.09 - Master's Thesis
Organization:FN - School of Science
Abstract:Space weather refers to environmental conditions in the interplanetary space and Earth’s magnetosphere, ionosphere and exosphere and can influence the performance and reliability of electronics based technological systems. The major role in space weather changes plays the solar wind, a stream of charged particles (mostly electrons and protons) with energies of approximately 1 keV, that can cause geomagnetic storms and auroras. During their entry into the atmosphere, high energy cosmic rays collide with atomic nuclei of atmospheric gasses. When scattering occurs extensive air showers are created. Those cascades of secondary particles create flashes of light due to the Cherenkov effect as well as excite molecules of nitrogen gas in atmosphere, which then glow in fluorescent light. In order to observe the light created by air showers, it has to be collected with telescopes. The particles from the cascades that reach ground can be detected with surface detectors. The Pierre Auger Observatory is the largest observatory for cosmic ray measurements. It is located in Argentinian pampas covering an area of 3000 km2. It consists of 1660 surface detectors and 27 fluorescence telescopes. For cosmic rays with energies above few 1017 eV, a precise reconstruction of energy and direction of primary particle is achievable. Observatory also allows measurement of flux of incoming particles down to primary energies in ca. 10 GeV - 10 TeV interval, with a median energy ca. 80-90 GeV. This measurement capability is called "scaler" mode, since the corresponding data consist of scaler counted cascade particles with deposited energy between 15 and 100 MeV, at the average rate of 2 kHz per individual surface detector. For the purpose of this master thesis I compared the data from scaler mode measurements with measurements of neutron monitors, which are commonly used for space weather observations. With the correlation received from the comparison, I showed that scaler mode operation of Pierre Auger observatory can be used to monitor space weather events such as solar cycle and the decreases in the observed galactic cosmic ray intensity due to solar wind (Forbush decrease).
Keywords:Pierre Auger Observatory, cosmic rays, space weather, Forbush decrease
Place of publishing:Nova Gorica
Year of publishing:2019
PID:20.500.12556/RUNG-4739-b15a2218-a753-0a59-945a-38d439820fce New window
COBISS.SI-ID:5451515 New window
NUK URN:URN:SI:UNG:REP:ISZ1KGBP
Publication date in RUNG:17.09.2019
Views:6065
Downloads:196
Metadata:XML DC-XML DC-RDF
:
Copy citation
  
Average score:(0 votes)
Your score:Voting is allowed only for logged in users.
Share:Bookmark and Share


Hover the mouse pointer over a document title to show the abstract or click on the title to get all document metadata.

Secondary language

Language:Slovenian
Title:Raziskave vesoljskega vremena z observatorijem Pierre Auger
Abstract:Izraz vesoljsko vreme se uporablja za spremenljive pogoje v medplanetarnem prostoru v bližini Zemlje, ki vplivajo na Zemeljsko magnetosfero, ionosfero in eksosfero. Eden izmed glavnih vzrokov za vesoljsko vreme je sončev veter, tok nabitih delcev (elektronov in protonov) z energijami okoli 1 keV, ki lahko povzroca geomagnetne nevihte (perturbacije v Zemeljski magnetosferi) in polarni sij. Vpliva tudi na druge kozmicne delce z višjimi energijami, ki vpadajo v Zemeljsko atmosfero. Pri sipanju visokoenergijskih kozmicnih delcev na atomskih jedrih atmosferskih plinov pride do nastanka plazov sekundarnih delcev, ki jih je mogoce zaznati preko detekcije fluorescence ali pojava Cerenkova v atmosferi, bodisi z meritvami nabitih delcev, ki dosežejo površje. Najvecji observatorij na svetu za meritve lastnosti kozmicnih žarkov je observatorij Pierre Auger v Argentini, ki pokriva površino 3000 km2. Kot talne detektorje za meritve sekundarnih delcev, ki dosežejo površje, observatorij uporablja mrežo 1660 vodnih detektorjev cerenkova, hkrati pa uporablja tudi 27 fluorescencnih teleskopov za meritve lastnosti plazov v atmosferi. Smeri in energije kozmicnih delcev z energijami nad 1017 eV je mogoce rekonstruirati iz koincidence signalov iz vec talnih detektorjev. Observatorij omogoca tudi meritev fluksa primarnih kozmicnih delcev z nižjimi energijami (med 10 GeV in 10 TeV) v t. i. “scaler” nacinu, kjer neodvisno merimo število vpadlih kozmicnih delcev v vsakem posameznem talnem detektorju. Pri scaler nacinu so prešteti vsi iz kaskad, katerih energijska sled v detektorju, ni nižja od 15MeV in ne presega 100 MeV. Povprecna frekvenca sledi na detektor je približno 2 kHz. Podatke, pridobljene v scaler nacinu meritev sem primerjal s podatki, pridobljenimi z nevtronskimi opazovalnicami, ki se jih uporablja za opazovanje vesoljskega vremena. S korelacijo, dobljeno pri primerjavi, sem pokazal, da je z nizkoenergijskim nacinom delovanja observatorija Pierre Auger ravno tako mogoce spremljati dolgorocne spremembe vesoljskega vremena, kot je soncev cikel in zmanjšanje števila visokoenergijskih delcev, ki dosežejo Zemljo zaradi soncnih vetrov (Forbushev pojav).
Keywords:observatorij Pierre Auger, kozmicni delci, vesoljsko vreme, Forbush decrease


Back