263 citations · 1.3k across the 100 of their papers we have counts for
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Detection of 6 K gas in Ophiuchus D
J. Harju, M. Juvela, S. Schlemmer +3
Cold cores in interstellar molecular clouds represent the very first phase in star formation. The physical conditions of these objects are studied in order to understand how molecu…
RXTE and INTEGRAL observations of IGR J19140+0951
Lionel Prat, Jerome Rodriguez, Diana C. Hannikainen
We have used the RXTE and INTEGRAL satellites simultaneously to observe the High Mass X-ray binary IGR J19140+0951. The spectra obtained in the 3-80 keV range have allowed us to pe…
The nature of the infrared counterpart of IGR J19140+0951
D. C. Hannikainen, M. G. Rawlings, P. Muhli +3
The INTEGRAL observatory has been (re-)discovering new X-ray sources since the beginning of nominal operations in early 2003. These sources include X-ray binaries, Active Galactic…
Simulations of polarized dust emission
V. -M. Pelkonen, M. Juvela, P. Padoan
Our aim is to study the polarization of thermal dust emission to see if the alignment of grain by radiative torques could explain the observed relation between the degree of polari…
XMM-Newton and Chandra observations of the ultra-compact binary RX J1914+24
Gavin Ramsay, Mark Cropper, Pasi Hakala
The nature of the X-ray source RX J1914+24 has been the subject of much debate. It shows a prominent period of 569 sec in X-rays and the optical/infra-red: in most models this has…
XMM-Newton observations of AM CVn binaries
Gavin Ramsay, Pasi Hakala, Tom Marsh +3
We present the results of XMM-Newton observations of four AM CVn systems -- AM CVn, CR Boo, HP Lib and GP Com. Their light curves show very different characteristics. The X-ray lig…
RApid Temporal Survey - RATS I: Overview and first results
Gavin Ramsay, Pasi Hakala
We present the aim and first results of the RApid Temporal Survey (RATS) made using the Wide Field Camera on the Isaac Newton Telescope. Our initial survey covers 3 square degrees,…
The X-ray source population of the globular cluster M15: Chandra high resolution imaging
D. C. Hannikainen, P. A. Charles, L. van Zyl +5
The globular cluster M15 was observed on three occasions with the High Resolution Camera on board Chandra in 2001 in order to investigate the X-ray source population in the cluster…
Discovery of a new INTEGRAL source: IGR J19140+0951
D. C. Hannikainen, J. Rodriguez, C. Cabanac +5
IGR J19140+0951 (formerly known as IGR J19140+098) was discovered with the INTEGRAL satellite in March 2003. We report the details of the discovery, using an improved position for…
IGR J19140+098, a new INTEGRAL transient
Juho Schultz, Diana C. Hannikainen, Osmi Vilhu +5
IGR J19140+098 (SIMBAD corrected name IGR J19140+0951) is a new X-ray transient, discovered by INTEGRAL during an observation of GRS 1915+015. The source presents strong variations…
Accretion stream mapping with genetically modified "fire-flies"
C. M. Bridge, Pasi Hakala, Mark Cropper +1
We apply an eclipse mapping technique using `genetically modified fire-flies' to the eclipse light curves of HU Aqr and EP Dra. The technique makes as few assumptions as possible a…
Multi-wavelength INTEGRAL NEtwork (MINE) observations of the microquasar GRS 1915+105
Yael Fuchs, J. Rodriguez, S. E. Shaw +9
We present the international collaboration MINE (Multi-lambda Integral NEtwork) aimed at conducting multi-wavelength observations of X-ray binaries and microquasars simultaneously…
INTEGRAL observations of the transient source IGR J19140+098
C. Cabanac, J. Rodriguez, P. O Petrucci +3
IGR J19140+098 was discovered during the early INTEGRAL observations of GRS1915+105 in March 2003. The following observations by INTEGRAL and RXTE show significant variability on v…
Morphology and kinematics of Lynds 1642
D. Russeil, M. Juvela, K. Lehtinen +2
The high latitude translucent molecular cloud L1642 has been mapped in the J=1-0 and J=2-1 transitions of 12CO, 13CO and C18O using the SEST radio telescope. We have analysed the m…
Stream eclipse mapping with 'fire-flies'
C. M. Bridge, Pasi Hakala, Mark Cropper +1
We apply a new method of eclipse mapping to the light curves of eclipsing polars. The technique aims to locate the bright emission associated with the accretion stream, using a tec…
Pair Annihilation and Radio Emission from Nova Muscae
D. C. Hannikainen, C. R. Kaiser
In the hard X-ray spectra of some X-ray binaries line features around 500 keV are detected. We interpret these as arising from pair annihilation in relativistic outflows leading to…
Molecular line study of evolution in protostellar cloud cores
S. Kontinen, J. Harju, A. Heikkila +1
Two dense dark cloud cores representing different stages of dynamical evolution were observed in a number of molecular spectral lines. One of the cores, Cha- MMS1 in the Chamaeleon…