Newly Determined Explosion Center of Tycho's Supernova and the Implications for Proposed Ex-Companion Stars of the Progenitor

Abstract

`Star G', near the center of the supernova remnant of Tycho's SN1572, has been claimed to be the ex-companion star of the exploding white dwarf, thus pointing to the progenitor being like a recurrent nova. This claim has been controversial, but there have been no confident proofs or disproofs. Previously, no has seriously addressed the question as to the exact explosion site in 1572. We now provide accurate measures of the supernova position by two radically different methods. Our first method is to use the 42 measured angular distances between the supernova in 1572 and bright nearby stars, with individual measures being as good as 84 arc-seconds, and all resulting in a position with a 1-$\sigma$ error radius of 39 arc-seconds (including systematic uncertainties). Our second method is to use a detailed and realistic expansion model for 19 positions around the edge of the remnant, where the swept-up material has measured densities, and we determine the center of expansion with a chi-square fit to the 19 measured radii and velocities. This method has a 1-$\sigma$ error radius of 7.5 arc-seconds. Both measures are substantially offset from the geometric center, and both agree closely, proving that neither has any significant systematic errors. Our final combined position for the site of the 1572 explosion is J2000 $\alpha$=0h 25m 15.36s, $\delta =64^{\circ }{8}^{\prime }40.2"$, with a 7.3 arc-second 1-sigma uncertainty. Star G is rejected at the 8.2-$\sigma$ confidence level. Our new position lies mostly outside the region previously searched for ex-companion stars.

to be published in ApJ

References in corpus (6)

• Tycho Brahe's 1572 supernova as a standard type Ia explosion revealed from its light echo spectrum
• Scattered-Light Echoes from the Historical Galactic Supernovae Cassiopeia A and Tycho (SN 1572)
• A Precise Proper Motion for the Crab Pulsar, and the Difficulty of Testing Spin-Kick Alignment for Young Neutron Stars
• No surviving evolved companions to the progenitor of supernova SN 1006
• Investigation of the Progenitors of the Type Ia Supernovae Associated With the LMC Supernova Remnants 0505-67.9 and 0509-68.7
• The Diffuse Source at the Center of LMC SNR 0509-67.5 is a Background Galaxy at z = 0.031

Cited by in corpus (14)

• Expanding molecular bubble surrounding Tycho's supernova remnant (SN 1572) observed with IRAM 30 m telescope: evidence for a single-degenerate progenitor
• A common-envelope wind model for Type Ia supernovae (I): binary evolution and birth rate
• Imprints of the ejecta-companion interaction in Type Ia supernovae: main sequence, subgiant, and red giant companions
• An X-ray and Radio Study of the Varying Expansion Velocities in Tycho's Supernova Remnant
• Surviving companions of Type Ia supernovae: theory and observations
• The Three-Dimensional Expansion of the Ejecta from Tycho's Supernova Remnant
• Binary companions of nearby supernova remnants found with Gaia
• Subdwarf B stars as possible surviving companions in Type Ia supernova remnants
• Search for Surviving Companions of Progenitors of Young LMC Type Ia Supernova Remnants
• Rapid Deceleration of Blast Waves Witnessed in Tycho's Supernova Remnant
• Tycho's supernova: the view from {\it Gaia}
• An Expanding Shell of Neutral Hydrogen Associated with SN 1006: Hints for the Single-Degenerate Origin and Faint Hadronic Gamma-Rays
• An explanation of the formation of the peculiar periphery of Tycho's supernova remnant
• Estimating Global Ejecta Mass Ratios in Tycho's SNR