Distance and total column density to the periodic radio star LSI + 61 deg 303

Frail, D. A.; Hjellming, R. M.

doi:10.1086/115833

Cited by 87 publications

(78 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the cases of the microquasars LS 5039 and LS I +61 303 the luminosity intervals correspond to intrinsic variability of the sources at the corresponding distances, while in the case of AX J1639.0−4642 they reflect the range of assumed possible distances. Frail & Hjellming (1991); m computed assuming α = −1.…”

Section: Microquasars As Possible Counterparts Of Unidentified Egret mentioning

confidence: 99%

The dust-enshrouded microquasar candidate AX J1639.0-4642 = IGR J16393-4643

Combi

Ribó

Mirabel

et al. 2004

A&A

View full text Add to dashboard Cite

Abstract. We present a multiwavelength study of the field containing the unidentified X-ray source AX J1639.0−4642, discovered with the ASCA observatory and recently detected with the IBIS telescope, onboard the INTEGRAL satellite, dubbed IGR J16393−4643. The huge hydrogen column density towards the source, the hard spectral index in the 0.7-10 keV band and its flux variability suggest that the source is a High Mass X-ray Binary (HMXB) enshrouded by dust. Our search reveals the presence of a non-thermal radio counterpart within the X-ray error box. After a study of the broadband emission from X-rays to the radio domain, we propose that AX J1639.0−4642 is a dust-enshrouded Microquasar (MQ) candidate. In addition, the X-ray source is well within the 95% location contour of the unidentified γ-ray source 3EG J1639−4702. The main properties of AX J1639.0−4642/3EG J1639−4702 are consistent with those of two other MQs previously proposed to display high-energy γ-ray emission.

show abstract

Section: Microquasars As Possible Counterparts Of Unidentified Egret mentioning

confidence: 99%

The dust-enshrouded microquasar candidate AX J1639.0-4642 = IGR J16393-4643

Combi

Ribó

Mirabel

et al. 2004

A&A

View full text Add to dashboard Cite

show abstract

“…The stellar luminosity is L = 10 38 erg s −1 (Hutchings & Crampton 1981), and the distance ∼2 kpc (Frail & Hjellming 1991). Massi et al (2001Massi et al ( , 2004 detected mildly relativistic radio jets in LS I +61 303 with a velocity V jet ∼ 10 10 cm s −1 , pointing to its microquasar nature.…”

Section: Introductionmentioning

confidence: 97%

The radio to TeV orbital variability of the microquasar LS I +61 303

Bosch‐Ramon¹,

Paredes²,

Romero³

et al. 2006

A&A

View full text Add to dashboard Cite

Context. The microquasar LS I +61 303 has recently been detected at TeV energies by the Cherenkov telescope MAGIC, presenting variability on timescales similar to its orbital period. This system has been intensively observed at different wavelengths during the last three decades, showing a very complex behavior along the orbit. Aims. We aim to explain, using a leptonic model in the accretion scenario, the observed orbital variability and spectrum from radio to TeV energies of LS I +61 303. Methods. We apply a leptonic model based on accretion of matter from the slow inhomogeneous equatorial wind of the primary star, assuming particle injection proportional to the accretion rate. The relativistic electron energy distribution within the binary system is computed taking into account convective/adiabatic and radiative losses. The spectral energy distribution (SED) has been calculated accounting for synchrotron and (Thomson/Klein Nishina -KN-) inverse Compton (IC) processes and the photon-photon absorption in the ambient photon fields. The angle dependence of the photon-photon and IC cross sections has been considered in the calculations. Results. We reproduce the main features of the observed light curves from LS I +61 303 at radio, X-rays, high-energy (HE), and very high-energy (VHE) gamma-rays, and the whole spectral energy distribution. Conclusions. Our model is able to explain the radio to TeV orbital variability taking into account that radiation along the orbit is strongly affected by the variable accretion rate, the magnetic field strength, and by the ambient photon field via dominant IC losses and photon-photon absorption at periastron.

show abstract

“…In 1993, a VLBI observation of LS I +61 • 303 showed that the radio emission had a structure of milliarcsecond (mas) size corresponding to a few AU at the distance of 2.0 kpc (Massi et al 1993;Frail & Hjellming 1991). The complex morphology in successive VLBI observations Paredes et al 1998;Taylor et al 2000;Massi et al 2001Massi et al , 2004 highlighted the unlikelihood of an interpretation in terms of a microquasar with a constant position angle.…”

Section: Introductionmentioning

confidence: 99%

VLBA images of the precessing jet of LS I +61°303

Massi

Ros

Zimmermann

2012

A&A

View full text Add to dashboard Cite

Context. In 2004, changes in the radio morphology of the Be/X-ray binary system LS I +61 • 303 suggested that it is a precessing microquasar. In 2006, a set of VLBA observations performed throughout the entire orbit of the system were not used to study its precession because the changes in radio morphology could tentatively be explained by the alternative pulsar model. However, a recent radio spectral index data analysis has confirmed the predictions of the two-peak microquasar model, which therefore does apply in LS I +61 • 303. Aims. We revisit the set of VLBA observations performed throughout the orbit to determine the precession period and improve our understanding of the physical mechanism behind the precession. Methods. By reanalyzing the VLBA data set, we improve the dynamic range of images by a factor of four, using self-calibration. Different fitting techniques are used and compared to determine the peak positions in phase-referenced maps. Results. The improved dynamic range shows that in addition to the images with a one-sided structure, there are several images with a double-sided structure. The astrometry indicates that the peak in consecutive images for the whole set of observations describes a well-defined ellipse, 6−7 times larger than the orbit, with a period of about 28 d. Conclusions. A double-sided structure is not expected to be formed from the expanding shocked wind predicted in the pulsar scenario. In contrast, a precessing microquasar model can explain the double-and one-sided structures in terms of variable Doppler boosting. The ellipse defined by the astrometry could be the cross-section of the precession cone, at the distance of the 8.4 GHz-core of the steady jet, and 28 d the precession period.

show abstract

Distance and total column density to the periodic radio star LSI + 61 deg 303

Cited by 87 publications

References 0 publications

The dust-enshrouded microquasar candidate AX J1639.0-4642 = IGR J16393-4643

The dust-enshrouded microquasar candidate AX J1639.0-4642 = IGR J16393-4643

The radio to TeV orbital variability of the microquasar LS I +61 303

VLBA images of the precessing jet of LS I +61°303

Contact Info

Product

Resources

About