Deep infrared observations of the puzzling central X-ray source in RCW103

Abstract

1E 161348-5055 (1E 1613) is a point-like, soft X-ray source originally identified as a radio-quiet, isolated neutron star, shining at the center of the 2000 yr old supernova remnant RCW103. 1E 1613 features a puzzling 6.67 hour periodicity as well as a dramatic variability over a time scale of few years. Such a temporal behavior, coupled to the young age and to the lack of an obvious optical counterpart, makes 1E 1613 a unique source among all compact objects associated to SNRs. It could either be the first low-mass X-ray binary system discovered inside a SNR, or a peculiar isolated magnetar with an extremely slow spin period. Analysis of archival IR observations, performed in 2001 with the VLT/ISAAC instrument, and in 2002 with the NICMOS camera onboard HST unveils a very crowded field. A few sources are positionally consistent with the refined X-ray error region that we derived from the analysis of 13 Chandra observations. To shed light on the nature of 1E 1613, we have performed deep IR observations of the field with the NACO instrument at the ESO/VLT, searching for variability. We find no compelling reasons to associate any of the candidates to 1E 1613. On one side, within the frame of the binary system model for the X-ray source, it is very unlikely that one of the candidates be a low-mass companion star to 1E 1613. On the other side, if the X-ray source is an isolated magnetar surrounded by a fallback disc, we cannot exclude that the IR counterpart be hidden among the candidates. If none of the potential counterparts is linked to the X-ray source, 1E 1613 would remain undetected in the IR down to Ks>22.1. Such an upper limit is consistent only with an extremely low-mass star (an M6-M8 dwarf) at the position of 1E 1613, and makes rather problematic the interpretation of 1E 1613 as an accreting binary system.

26 pages, 5 figures. Accepted for publication in ApJ

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• 1E161348-5055 in the Supernova Remnant RCW 103: A Magnetar in a Young Low Mass Binary System?
• VLT observations of the Central Compact Object in the Vela Jr. supernova remnant
• VLT observations of Compact Central Objects

Cited by in corpus (22)

• Grand Unification in Neutron Stars
• Systematic study of magnetar outbursts
• Central Compact Objects in Supernova Remnants
• Magnetar-like activity from the central compact object in the SNR RCW103
• Comparing Neutron Star Kicks to Supernova Remnant Asymmetries
• Optical, ultraviolet, and infrared observations of isolated neutron stars
• Evidence for the magnetar nature of 1E 161348-5055 in RCW 103
• Evidence for an abundant old population of Galactic ultra long period magnetars and implications for fast radio bursts
• Stellar Binaries That Survive Supernovae
• Ejector and propeller spin-down: How might a superluminous supernova millisecond magnetar become the 6.67 hr pulsar in RCW103
• X-ray emission from isolated neutron stars
• Chandra Observations of SNR RCW 103
• Swift monitoring of the central X-ray source in RCW 103
• Near Infrared Counterpart of 2E 1613.5-5053, the Central Source in Supernova Remnant RCW 103
• HST and VLT observations of the neutron star 1E 1207.4-5209
• Young pre-Low-Mass X-ray Binaries in propeller phase : Nature of the 6.7-hour periodic X-ray source 1E 161348-5055 in RCW 103
• XMM-Newton X-ray Detection of the High Magnetic Field Radio Pulsar PSR B1916+14
• Gazing at the ultra-slow magnetar in RCW 103 with NuSTAR and Swift
• On the fallback disk around the slowest isolated pulsar, 1E 161348$-$5055
• Central compact objects in Kes 79 and RCW 103 as "hidden" magnetars with crustal activity
• Long X-ray flares from the central source in RCW 103
• The nature of the infrared counterpart and of the optical nebula associated with the Central Compact Object in Vela Jr.\