RX J0852.0−4622

RX J0852.0−4622 (also known as G266.2−1.2) is a

It was found in 1998 with an analysis of data from the ROSAT x-ray telescope.^[4] Published simultaneously with its discovery was a claimed detection by the Compton Gamma Ray Observatory of a gamma ray spectral line of ⁴⁴Ti which has a half-life of 60 years and therefore seemed to indicate a young provenance for the supernova, perhaps the youngest one yet discovered.^[5] Later independent groups could not reproduce the detection, and so the consensus is that the identification of this line was likely spurious.^[6] Since the age and distance are correlated, a young, nearby supernova like this has inspired some detective work to identify evidence that such a supernova may have been observed and recorded by groups of people,^[7] and geochronologists have looked for evidence of a young supernova in tree ring^[8] and ice core data,^[9] but identification of claimed correlate signals have not been conclusively made.^[2] The latest analyses of the remnant indicate an age of at least 2400 years (and possibly much older), a distance of no less than 500 parsecs, and a radial size of at least 8 parsecs.^[2]

The central compact object (CCO) was discovered in 2001.^[10] In the initial Chandra X-ray image and deeper images thereafter, no pulsations were detected from the compact remnant, which is believed to be the neutron star CXOU J085201.4-461753. A different pulsar was suggested as the remnant,^[11] but its kinematics do not conform as well to the observed kinematics of the remnant shell.^[2]

References