A soft-spectrum PULX candidate is reported in Cen A but XMM-SAS randomisation during data reduction renders the marginal 1.27 Hz pulsation detection unreliable across repeated reductions.
A 78 Day X-ray Period Detected from NGC 5907 ULX1 by Swift
2 Pith papers cite this work. Polarity classification is still indexing.
2
Pith papers citing it
abstract
We report the detection of a $78.1\pm0.5$ day period in the X-ray lightcurve of the extreme ultraluminous X-ray source NGC 5907 ULX1 ($L_{\rm{X,peak}}\sim5\times10^{40}$ erg s$^{-1}$), discovered during an extensive monitoring program with Swift. These periodic variations are strong, with the observed flux changing by a factor of $\sim$3-4 between the peaks and the troughs of the cycle; our simulations suggest that the observed periodicity is detected comfortably in excess of 3$\sigma$ significance. We discuss possible origins for this X-ray period, but conclude that at the current time we cannot robustly distinguish between orbital and super-orbital variations.
fields
astro-ph.HE 2years
2026 2representative citing papers
A modified ellipsoidal modulation model with precessing disk irradiation effects revises the SMC X-1 pulsar mass to approximately 1.35 solar masses.
citing papers explorer
-
Significant or Not? The Impact of Randomisation During Data Reduction on Confirming a New Pulsating Ultraluminous X-ray Source Candidate in Centaurus A
A soft-spectrum PULX candidate is reported in Cen A but XMM-SAS randomisation during data reduction renders the marginal 1.27 Hz pulsation detection unreliable across repeated reductions.
-
Optical Super-orbital Modulation of SMC X-1: Disk Precession and a Revised Pulsar Mass
A modified ellipsoidal modulation model with precessing disk irradiation effects revises the SMC X-1 pulsar mass to approximately 1.35 solar masses.