37 research outputs found
Sub-arcsecond radio and optical observations of the likely counterpart to the gamma-ray source 2FGL J2056.7+4939
We have searched and reviewed all multi- wavelength data available for the
region towards the gamma-ray source 2FGL J2056.7+4939 in order to con- strain
its possible counterpart at lower energies. As a result, only a point-like
optical/infrared source with flat-spectrum radio emission is found to be
consistent with all X-ray and gamma-ray error circles. Its struc- ture is
marginally resolved at radio wavelengths at the sub-arcsecond level. An
extragalactic scenario appears to be the most likely interpretation for this
object.Comment: 5 pages, 3 figures, 1 tabl
A well-monitored, X-ray selected, tidal disruption event
We report on a candidate tidal disruption event detected in the XMM-Newton slew survey from the nucleus of SDSS J120136.02+300305.5 (z = 0.146; hereafter SDSS J1201+30). The source, monitored by Swift and XMM-Newton, was highly variable on timescales of a week, reaching a peak X-ray luminosity of 3 × 1044 ergs/s. The light curve is reminiscent of the variations seen in SWIFT J1644+57, although in this case the absence of radio flux rules out a jet mechanism for the emission. The X-ray spectrum is steep, (spectral index = 3–5) and softens with diminishing flux. It is inconsistent with a single or multi-temperature black-body model but may be fit with Bremsstrahlung or comptonised thermal emission
Tidal disruption events from the first XMM-Newton slew survey
Observations over the past decade have revealed that supermassive black holes (SMBHs) likely reside at the centres of most or all bulge galaxies. Confirmation of their dormant presence in non-active galaxies is difficult to obtain. An unavoidable consequence of the existence of remnant SMBHs is the detection of a tidal disruption event. This is discovered as flaring radiation produced when a star is tidally disrupted and subsequently accreted by the black hole. Two of these exceptional events have been discovered by XMM-Newton in the first slew catalogue, NGC 3599 and SDSS J132341.97+482701.3. Here we show their evolution up to four years after the peak of the outburst including a detailed analysis of NGC 3599, for which novel follow-up observations are presented here
A well-monitored, X-ray selected, tidal disruption event
We report on a candidate tidal disruption event detected in the XMM-Newton slew survey from the nucleus of SDSS J120136.02+300305.5 (z = 0.146; hereafter SDSS J1201+30). The source, monitored by Swift and XMM-Newton, was highly variable on timescales of a week, reaching a peak X-ray luminosity of 3 × 1044 ergs/s. The light curve is reminiscent of the variations seen in SWIFT J1644+57, although in this case the absence of radio flux rules out a jet mechanism for the emission. The X-ray spectrum is steep, (spectral index = 3–5) and softens with diminishing flux. It is inconsistent with a single or multi-temperature black-body model but may be fit with Bremsstrahlung or comptonised thermal emission
Host galaxy line diagnostics for the candidate tidal disruption events XMMSL1Â J111527.3+180638 and PTF09axc
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Tidal disruption events from the first XMM-Newton slew survey
Observations over the past decade have revealed that supermassive black holes (SMBHs) likely reside at the centres of most or all bulge galaxies. Confirmation of their dormant presence in non-active galaxies is difficult to obtain. An unavoidable consequence of the existence of remnant SMBHs is the detection of a tidal disruption event. This is discovered as flaring radiation produced when a star is tidally disrupted and subsequently accreted by the black hole. Two of these exceptional events have been discovered by XMM-Newton in the first slew catalogue, NGC 3599 and SDSS J132341.97+482701.3. Here we show their evolution up to four years after the peak of the outburst including a detailed analysis of NGC 3599, for which novel follow-up observations are presented here