Repository of University of Nova Gorica

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

Title:Simulations of Tidal Disruption Events Observations with the LSST
Authors:ID Bricman, Katja (Copyright holder)
ID Bricman, Katja, University of Nova Gorica (Author)
ID Gomboc, Andreja (Mentor) More about this mentor... New window
Files: This document has no files that are freely available to the public. This document may have a physical copy in the library of the organization, check the status via COBISS. Link is opened in a new window
Language:English
Work type:Not categorized
Typology:2.09 - Master's Thesis
Organization:UNG - University of Nova Gorica
Abstract:The Large Synoptic Survey Telescope (LSST) will produce a multi-colour survey of 25000 square deg of the Southern sky during its 10 years of operations. It will observe over 20 billion galaxies and a similar number of stars, map the Solar System and the Milky Way, and probe dark matter and dark energy. In addition, it will discover thousands of transients every night, including new classes of objects, which have not yet been observed. Due to its large coverage of the sky it will be a perfect tool for the search of rare Tidal Disruption Events (TDEs), which occur when a star passes close by a supermassive black hole and gets disrupted by its tidal force. Afterwards the stellar debris fall back to the black hole, initially at a rate exceeding the Eddington rate, producing an outflow, which releases a flare of energy. When the fallback rate subsides below the Eddington rate, the gas accretes onto the black hole via accretion disk. The LSST simulation framework enables us to simulate observations of different types of objects with the LSST. In this work, we include TDEs in the LSST simulation framework, estimate the number of detected TDEs, and simulate their light curves using a theoretical model, which predicts a t^(-2.6) light curve decline with time in the outflow phase and a t^{-0.4} decline in the disk phase. We also take a closer look at the distribution of the detected TDEs over cosmological redshift and black hole mass.
Keywords:Astronomical observations, Large Synoptic Survey Telescope, Tidal Disruption Events, Black Holes, simulations
Publication status:Published
Place of publishing:Ljubljana
Publisher:Fakulteta za Matematiko in Fiziko, Univerza v Ljubljani
Year of publishing:2017
Number of pages:86
PID:20.500.12556/RUNG-3319-cc434547-0f92-f222-69bc-3722ce697184 New window
COBISS.SI-ID:3124836 New window
NUK URN:URN:SI:UNG:REP:KVV2K1FM
Publication date in RUNG:17.10.2017
Views:5013
Downloads:0
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:Simulacije opazovanj plimskega raztrganja zvezd z Velikim sinoptičnim pregledovalnim teleskopom
Abstract:Veliki sinoptični pregledovalni teleskop (LSST) bo predvidoma 10 let opazoval 25000 kvadratnih ločnih stopinj veliko območje južnega neba in s tem ustvaril večbarvni pregled neba. V času delovanja bo opazoval 20 milijard galaksij in podobno število zvezd, kartiral Sončev sistem in Galaksijo, ter raziskoval temno snov in temno energijo. Poleg tega bo vsako noč odkril na tisoče tranzientnih dogodkov, med njimi pa bo odkrival tudi takšne objekte, ki do zdaj še niso bili opaženi in so nam še neznani. Ker bo LSST s svojimi opazovanji pokril zelo velik del neba, bo teleskop odlično orodje za iskanje redkih pojavov plimskega raztrganja zvezd. Do plimskega raztrganja zvezde pride, ko se zvezda znajde dovolj blizu supermasivni črni luknji, da lahko njena plimska sila raztrga zvezdo. Po raztrganju ostanki zvezde padajo proti črni luknji. V začetni fazi je količina padanja snovi večja od Eddingtonove limite, zaradi česar snov odpihne iz sistema, nastali veter pa odda blišč svetlobe. Ko količina materiala, ki se vrača proti črni luknji, pade pod Eddingtonovo limito, zvezdni plin pada v črno luknjo prek akrecijskega diska. Simulacijsko orodje teleskopa LSST omogoča simulacije opazovanj različnih vrst objektov s tem teleskopom. V delu smo v simulacijsko orodje teleskopa LSST vključili dogodke plimskih raztrganj zvezd, ocenili število odkritih dogodkov in simulirali njihove svetlobne krivulje. Pri tem smo uporabili teoretični model svetlobne krivulje, ki napoveduje časovno odvisnost svetlobne krivulje plimskih raztrganj zvezd t^(−2.6) v fazi vetra in t^(-0.4) v fazi akrecijskega diska. Podrobneje smo predstavili tudi porazdelitev opazovanih plimskih raztrganj po oddaljenosti oziroma kozmološkem rdečem premiku in masi supermasivne črne luknje.
Keywords:Astronomska opazovanja, Veliki sinoptični pregledovalni teleskop, plimsko raztrganje zvezd, črne luknje, simulacije


Back