A well-monitored, X-ray selected, tidal disruption event

¹ XMM SOC, ESAC, Apartado 78, 28691 Villanueva de la Cañada, Madrid, Spain
² Dept. of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK
³ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
⁴ Centro de Astrobiología (CSIC-INTA), 28850 Torrejón de Ardoz, Madrid, Spain

^a e-mail: richard.saxton@sciops.esa.int

Abstract

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.