M. Nissinen
A5030968659- Gamma-ray bursts and supernovae
- SAS software applications and methods
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- Astrophysical Phenomena and Observations
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Pulsars and Gravitational Waves Research
- Planetary Science and Exploration
- Astrophysics and Cosmic Phenomena
- Atmospheric Ozone and Climate
- Space Exploration and Technology
- Space Satellite Systems and Control
- Isotope Analysis in Ecology
- History and Developments in Astronomy
- Magnetic confinement fusion research
- Law, logistics, and international trade
- Spectroscopy and Laser Applications
- Particle Accelerators and Free-Electron Lasers
- Radio Astronomy Observations and Technology
- Space exploration and regulation
- Radiopharmaceutical Chemistry and Applications
- Island Studies and Pacific Affairs
- Relativity and Gravitational Theory
- Historical Astronomy and Related Studies
Ursa Astronomical Association
2021-2023
Taurus Hill Observatory
2008-2022
VTT Technical Research Centre of Finland
2007
Finnish Meteorological Institute
2006
(Abridged) OJ287 is a BL Lac object that has shown double-peaked bursts at regular intervals of ~12 yr during the last ~40 yr. We analyse optical photopolarimetric monitoring data from 2005-2009, which latest outburst occurred. The aim this study twofold: firstly, we to variability patterns and statistical properties polarization light-curve. find strong preferred position angle in polarization. can be explained by separating jet emission into two components: an core chaotic emission. stable...
We present photometry and spectroscopy of the type IIP supernova 2009bw in UGC 2890 from few days after outburst to 241 days. The light curve SN during photospheric phase is similar that normal SNe but with brighter peak plateau (Mmax R = -17.82 mag, Mplateau -17.37 mag). luminosity drop nebular one fastest ever observed, ~2.2 mag about 13 radioactive tail bolometric indicates amount ejected 56 Ni \approx 0.022 M\odot. spectra reveal high velocity lines H{\alpha} H{\beta} until 105 shock...
We present ultraviolet, optical, near-infrared photometry and spectroscopy of SN 2009N in NGC 4487. This object is a type II-P supernova with spectra resembling those subluminous supernovae, while its bolometric luminosity similar to that the intermediate 2008in. created SYNOW models plateau phase for line identification measure expansion velocity. In we find signs indicating possible weak interaction between ejecta pre-existing circumstellar material. These are also previously unpublished...
The blazar OJ 287 has produced two major optical outburst events during the years 2005–2008. These are latest in a series of outbursts that have occurred repeatedly at 12 year intervals since early 1900s. It been possible to explain historical light curve fairly well by using binary black hole model where secondary impacts accretion disk primary twice orbital cycle. We will ask here how does light-curve fit with this model. use 10 million particle hole. rate transfer particles through...
We present a comprehensive analysis of bright, long duration (T90 ~ 257 s) GRB 110205A at redshift z= 2.22. The optical prompt emission was detected by Swift/UVOT, ROTSE-IIIb and BOOTES telescopes when the still radiating in gamma-ray band. Nearly 200 s observations were obtained simultaneously from optical, X-ray to gamma-ray, which makes it one exceptional cases study broadband spectral energy distribution across 6 orders magnitude during phase. By fitting time resolved spectra, we clearly...
The long ${\it Swift}$ gamma-ray burst GRB 120326A at redshift $z=1.798$ exhibited a multi-band light curve with striking feature: late-time, long-lasting achromatic rebrightening, rarely seen in such events. Peaking optical and X-ray bands $\sim 35$ ks ($\sim 12.5$ the rest frame) after 70-s prompt burst, feature brightens nearly two orders of magnitude above underlying power-law decay. Modelling multiwavelength curves, we investigate possible causes rebrightening context standard fireball...
The massive outburst of the comet 17P/Holmes in October 2007 is largest known by a thus far. We present new comprehensive model describing evolution dust trail produced this phenomenon. comprises multiparticle Monte Carlo approach including solar radiation pressure effects, gravitational disturbance caused Venus, Earth and Moon, Mars, Jupiter Saturn, interaction particles with parent itself. Good accuracy computations achieved its implementation Orekit, which executes Dormad-Prince numerical...
Abstract We obtained well-sampled optical photometry of GRB 110213A, including Swift/UVOT and XRT. Combining our data from those other ground-based telescopes, we present 15 multicolor light curves showing similar shapes with two peaks. In contrast, in the X-ray band, only a single peak is observed between Temporal spectral analysis 110213A shows that X-rays differ for Phases I–III (before second band at ∼5.6 ks). Moreover, they have same behavior late times (Phases IV–VI). These indicate...