* Astronomy

Title: The ordinary life of the gamma-ray emitting Narrow-Line Seyfert 1 galaxy PKS 1502+036
Authors: F. D'Ammando (Dep. of Physics, Univ. of Perugia, INAF-IRA Bologna), M. Orienti (INAF-IRA Bologna, Bologna University), A. Doi (ISAS, JAXA), M. Giroletti (INAF-IRA Bologna), D. Dallacasa (Bologna University, INAF-IRA Bologna), T. Hovatta (Cahill Center for Astronomy and Astrophysics), A. J. Drake (California Institute of Technology), W. Max-Moerbeck (Cahill Center for Astronomy and Astrophysics), A. C. S. Readhead (Cahill Center for Astronomy and Astrophysics), J. L. Richards (Dep. of Physics, Purdue University)

We report on multifrequency observations of the gamma-ray emitting Narrow-Line Seyfert 1 galaxy PKS 1502+036 performed from radio to gamma rays during 2008 August-2012 November by Fermi-LAT, Swift (XRT and UVOT), OVRO, VLBA, and VLA. No significant variability has been observed in gamma rays, with 0.1-100 GeV flux that ranged between (3-7)x10^-8 ph/cm²/s using 3-month time bins. The photon index of the LAT spectrum (Gamma=2.60±0.06) and the apparent isotropic gamma-ray luminosity, L(0.1-100 GeV)= 7.8x10^45 erg/s, over 51 months are typical of a flat spectrum radio quasar. The radio spectral variability and the one-sided structure, in addition to the observed gamma-ray luminosity, suggest a relativistic jet with a high Doppler factor. In contrast to SBS 0846+513, the VLBA at 15 GHz did not observe superluminal motion for PKS 1502+036. Despite having the optical characteristics typical of a Narrow-Line Seyfert 1 galaxy, radio and gamma-ray properties of PKS 1502+036 are found to be similar to those of a blazar at the low end of the black hole mass distribution for blazars. This is in agreement with what has been found in the case of the other gamma-ray emitting Narrow-Line Seyfert 1 SBS 0846+513.

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