activity
20102023
most citedRevealing the X-ray Variability of AGN with Principal Component Analysis

56 citations · 129 across the 7 of their papers we have counts for

collaborators

9 papers

astro-ph.HE2024

Galaxy-group-associated distances to Very High Energy gamma-ray emitting BL Lacs KUV 00311-1938 and S2 0109+22

Karri I. I. Koljonen, Elina Lindfors, Kari Nilsson +2

Blazars constitute the most numerous source class in the known extragalactic population of very high energy (VHE) gamma-ray sources. However, determining their redshifts is often c…

astro-ph.HE2024

The invisible black widow PSR J1720-0534: implications for the electron density towards the North Polar Spur

Karri I. I. Koljonen, Sindre S. Lindseth, Manuel Linares +2

Radio emission from pulsars can be used to map out their distances through dispersion measure (DM), which quantifies the amount of radio pulse dispersion. However, this method reli…

astro-ph.HE2023

A Gaia view of the optical and X-ray luminosities of compact binary millisecond pulsars

Karri I. I. Koljonen, Manuel Linares

In this paper, we study compact binary millisecond pulsars with low- and very low-mass companion stars (spiders) in the Galactic field, using data from the latest Gaia data release…

astro-ph.HE20231 cited

Secrets behind the RXTE/ASM light curve of Cyg X-3

Osmi Vilhu, Karri Koljonen, Diana Hannikainen

In wind-fed X-ray binaries, the radiatively driven wind of the primary star can be suppressed by the EUV irradiation of the compact secondary star, leading to an increased accretio…

astro-ph.HE202319 cited

The origin of optical emission lines in the soft state of X-ray binary outbursts: the case of MAXI J1820+070

K. I. I. Koljonen, K. S. Long, J. H. Matthews +1

The optical emission line spectra of X-ray binaries (XRBs) are thought to be produced in an irradiated atmosphere, possibly the base of a wind, located above the outer accretion di…

astro-ph.HE201942 cited

Bright mini-outburst ends the 12-year long activity of the black hole candidate Swift J1753.5-0127

Guobao Zhang, F. Bernardini, D. M. Russell +16

We present optical, UV and X-ray monitoring of the short orbital period black hole X-ray binary candidate Swift J1753.5-0127, focusing on the final stages of its 12year long out…