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arXiv · astro-ph/0504647

High-resolution observations of SN 2001gd in NGC 5033

Miguel A. Perez-Torres·A. Alberdi·J. M. Marcaide·M. A. Guerrero·P. Lundqvist·I. I. Shapiro·E. Ros·L. Lara·J. C. Guirado·K. W. Weiler·C. J. Stockdale
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Abstract

We report on 8.4 GHz VLBI observations of SN2001gd in the spiral galaxy NGC5033 made on 26 June 2002 and 8 April 2003. Our data nominally suggests a relatively strong deceleration for the expansion of SN2001gd, but we cannot dismiss the possibility of a free supernova expansion. From our VLBI observations on 8 April 2003, we inferred a minimum total energy in relativistic particles and magnetic fields in the supernova shell of E_min =(0.3-14) 10^{47} ergs, and a corresponding equipartition average magnetic field of B_min = (50--350) mG. We also present multiwavelength VLA measurements of SN2001gd, which are well fit by an optically thin, synchrotron spectrum, partially absorbed by thermal plasma. We obtain a supernova flux density of (1.02 +/- 0.05) mJy at the observing frequency of 8.4 GHz for the second epoch, which results in an isotropic radio luminosity of (6.0 +/- 0.3) * 10^{36} ergs between 1.4 and 43.3 GHz, at an adopted distance of 13.1 Mpc. Finally, we report on an XMM-Newton X-ray detection of SN2001gd on 18 December 2002. The supernova X-ray spectrum is consistent with optically thin emission from a soft component (associated with emission from the reverse shock) at a temperature around 1 keV. The observed flux corresponds to an isotropic X-ray luminosity of L_X = 1.4 +/- 0.4 * 10^{39} ergs/s in the (0.3-5) keV band. We suggest that both radio and X-ray observations of SN2001gd indicate that a circumstellar interaction similar to that displayed by SN1993J in M81 is taking place.

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Miguel A. Perez-Torres, A. Alberdi, J. M. Marcaide, M. A. Guerrero, P. Lundqvist, I. I. Shapiro, E. Ros, L. Lara, J. C. Guirado, K. W. Weiler, C. J. Stockdale. 2005-04-28. High-resolution observations of SN 2001gd in NGC 5033. https://doi.org/10.1111/j.1365-2966.2005.09102.x

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